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Gender Based Differences In Kinematic Response To The Catapult

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					Gender-Based Differences In Kinematic Response To
         The Catapult Phase Of Ejection

         B.S. Shender, G.R. Paskoff,
               V.C. Chancey,
               A.L. Schmidt,
       A.E. Austermann, K.B. Vasquez

               Naval Air Systems Command
               Human Systems Department
                Patuxent River, MD USA

         US Army Aeromedical Research Laboratory
              Injury Biomechanics Branch,
                  Ft. Rucker, AL USA

                barry.shender@navy.mil
                     (301) 342-8881

                                                    1
                                Biodynamics Data Resource

• NBDL was established in New Orleans, LA in 1971
• Impact acceleration program
   • Horizontal accelerator
   • Vertical accelerator
• 25 years of data collected until decommission in 1996
• Experimental data – accelerometer data, high speed video,
  physiology
• Other data – medical records, X-rays, anthropometry
• NBDL researchers systematically investigated human response
  to impact acceleration
   • Independent directions
   • Combined direction
   • Gender
   • Additional head supported mass
• In 2007, a joint project was instituted with USAARL
• Materials were transferred to USAARL from NAMRL and
  BDR was established to restore, preserve, and digitize database


                                                                    2
                             Objective


Development of neck injury mitigation technologies requires
understanding the kinematics of head motion during aircraft ejection



Resulting head kinematics may depend on anthropometric variations
as well as gender



  Using data previously collected from human volunteers exposed to
  impact acceleration at NBDL, determine if there are gender-based
                     differences in head motion




                                                                       3
                                         Methods

Two studies; common factors:
• +Gz acceleration impulse exposures on the Vertical
  Accelerator – simulate ejection catapult phase
• Volunteers were seated and restrained with custom
  restraints to minimize torso movement during the vertical
  acceleration exposures 
• Sensors attached to mounts at the volunteer's mouth (bite
  bar) and at the volunteer's base of neck (T1) provided
  linear and rotational head and neck responses
• Accelerometers attached to the vertical carriage measured
  the vertical input acceleration 
• High speed video from multiple sites (500 fps)
• Data corrected for sensor and camera calibrations,
  transformed to head and T1 anatomical coordinate systems



                                                              4
                                       Methods

Male study investigated the effects of added head weight
   • 16 Navy enlisted males (21 ± 3 yrs; 77 ± 11 kg; 177 ± 8 cm)
   • G levels increased from 3 G to 10 G in 1 G increments              T1 package w/
   • Data used for the present study only includes un-helmeted trials      plate and
                                                                        retention straps


                                                                              Mouth package
                                                                               w/ bite block
                                                                              and head strap




Female study:
   • G level increased from 3 G to 9 G in 1 G increments with
     repeated exposures at 5 G and 7 G: 3, 4, 5, 5, 6, 7, 7, 8, 9
   • 8 Navy enlisted females (21 ± 2 yrs; 63 ± 3 kg; 134 ± 23 cm)
   • Total of 57 runs – not all volunteers completed the series
   • Data also included ECG and MRIs before and after series


                                                                                               5
                                   Analysis


Sled acceleration:
   • Sled start time, onset rate, peak Gz, time to peak Gz
Head angular velocity and displacement:
   • Time from sled onset to initial reaction (defined as 10% peak velocity)
   • Peak velocity in flexion and extension
   • Time to peak flexion and extension
   • Align curves to peak flexion for comparison for velocity
   • Normalize displacement curves to 0 for comparison
Compare female response to male for similar G profiles:
   • Match subjects based on anthropometry – limited due to availability of data
   • General linear ANOVA with Bonferroni and Tukey-Kramer Multiple-
     Comparison post hoc tests (p<0.05)



                                                                                   6
                                                                   Analysis


                                                                                                   9G Head Angular Velocity
First sled motion is time
  projected to 0 from least                                  15                                    TFp             TXp
  squares line fit to rising
  portion between 20 to 50% of                               10

  peak acceleration *                                                                                                           Tp
                                                              5
                                                                                                           Fp
                                                     rad/s
Peak Flexion (Fp)
                                                              0
Peak Extension (Xp)
                                                                                                      Xp
Total magnitude head                                          -5
 excursion (Tp = Fp + Xp)
                                                                                     Sled onset
Time to Fp (TFp)                                             -10
                                                                       0.05
                                                                              0.09


                                                                                            0.19
                                                                                                   0.23
                                                                                                          0.28
                                                                                                                 0.33
                                                                                                                        0.37
                                                                                                                               0.42
                                                                                                                                      0.47
                                                                                                                                             0.51
                                                                                                                                                    0.56


                                                                                                                                                                 0.65


                                                                                                                                                                              0.74
                                                                                                                                                                                     0.79
                                                                   0




                                                                                     0.14




                                                                                                                                                           0.6


                                                                                                                                                                        0.7
Time to Xp (TXp)
                                                                                                                        Time (s)




          * Becker E. Stereoradiographic Measurements for Anatomically Mounted
          Instruments. 21st Stapp Conference, paper 770926. SAE International. 1977: 477-505.

                                                                                                                                                                                            7
                                                                                                                        G




                                                                                                          -4
                                                                                                               -2
                                                                                                                    0
                                                                                                                        2
                                                                                                                            4
                                                                                                                                6
                                                                                                                                    8
                                                                                                   0.00
                                                                                                   0.05
                                                                                                   0.09
                                                                                                   0.14
                                                                                                   0.18
                                                                                                   0.23
                                                                                                   0.27
                                                                                                   0.32
                                                                                                   0.36




                                                               AVG Male
                                                                                                   0.41




                                                                                        Time (s)
                                                                                                   0.45
                                                                                                                                        4G sled acceleration




                                                                                                   0.50
                                                                                                   0.54

                                                               AVG Fem
                                                                                                   0.59
                                                                                                   0.63
                                                                                                   0.68
                                                                                                   0.72
                                               G                                                   0.77




                                 -4
                                      -2
                                           0
                                               2
                                                   4
                                                       6
                                                           8




                          0.00
                          0.05
                          0.09
                          0.14
                          0.18
                          0.23
                          0.27
                          0.32
                                                                                                                                                               Acceleration Pulse Comparison




                          0.36
    AVG Male




                          0.41
               Time (s)




                          0.45
                                                                 6G sled acceleration




                          0.50
                          0.54
    AVG Fem




                          0.59
                          0.63
                          0.68
                          0.72
                          0.77
8
                                                Analysis
                                                                                      G exposures
                                             Head     Neck    Sitting    Neck
                              Wt     Ht     circum   circum   Height    breadth
  SS   Age Gender Wt (lb)    (kg)   (cm)     (cm)     (cm)     (cm)      (cm)     3    4    5   6   7   8   9
H00284 20    F    107.8      48.9   150.8     53.4     30.0    80.4       12.1         x   xx
H00295 23    F    110.0      49.9   157.5      *        *        *         *      x    x   xx   x xx
H00294 19    F    115.0      52.2   152.4      *        *        *         *      x    x   xx   x xx    x   x
H00292 19    F    130.8      59.3   155.4     54.6     33.3    84.7       11.0    x    x   xx   x xx    x   x
H00281 21    F    133.5      60.6   160.4     57.0     33.2    82.5       12.9    x    x   xx   x xx    x
H00289 21    F    147.5      66.9   164.1     56.5     33.0    86.3       11.7    x    x   xx   x  x
H00290 19    F    158.0      71.7   167.2     55.8     33.2    86.4       11.5    x    x   xx   x xxx   x   x
H00286 26    F    170.3      77.2   167.4     56.5     35.1    84.7       12.9    x    x   xx   x

H00236   27   M      136.0   61.7   167.3    55.7     34.9     88.5      11.5          x    x               x
H00237   21   M      149.0   67.6   174.9    57.8     37.6     87.7      13.4              xx   x
H00248   18   M      154.0   69.9   177.8    57.9     36.8     92.6      12.9               x
H00227   19   M      160.0   72.6   180.4    56.2     36.0     96.2      12.1     x                         x
H00235   19   M      165.0   74.8   171.5    55.9     40.2     88.4      14.1     x
H00242   22   M      169.0   76.7   173.8    57.0     38.5     94.2      12.7          x
H00249   20   M      173.0   78.5   190.3    55.7     37.7     93.8      12.7          x        x


Insufficient overlap to match for neck circumference or breadth or sitting height



         *: anthropometry data missing
                                                                                                                9
                                 Results: Female Response

                                                                                         G exposures
                                                Head     Neck    Sitting    Neck
                                 Wt     Ht     circum   circum   Height    breadth
      SS   Age Gender Wt (lb)   (kg)   (cm)     (cm)     (cm)     (cm)      (cm)     3    4    5   6   7   8   9
    H00284 20    F    107.8     48.9   150.8     53.4     30.0    80.4       12.1         x   xx
  S H00295 23    F    110.0     49.9   157.5      *        *        *         *      x    x   xx   x xx
    H00294 19    F    115.0     52.2   152.4      *        *        *         *      x    x   xx   x xx    x   x
    H00292 19    F    130.8     59.3   155.4     54.6     33.3    84.7       11.0    x    x   xx   x xx    x   x
Med H00281 21    F    133.5     60.6   160.4     57.0     33.2    82.5       12.9    x    x   xx   x xx    x
    H00289 21    F    147.5     66.9   164.1     56.5     33.0    86.3       11.7    x    x   xx   x  x
    H00290 19    F    158.0     71.7   167.2     55.8     33.2    86.4       11.5    x    x   xx   x xxx   x   x
  L H00286 26    F    170.3     77.2   167.4     56.5     35.1    84.7       12.9    x    x   xx   x

     H00236   27   M    136.0   61.7   167.3    55.7     34.9     88.5      11.5          x    x               x
     H00237   21   M    149.0   67.6   174.9    57.8     37.6     87.7      13.4              xx   x
     H00248   18   M    154.0   69.9   177.8    57.9     36.8     92.6      12.9               x
     H00227   19   M    160.0   72.6   180.4    56.2     36.0     96.2      12.1     x                         x
     H00235   19   M    165.0   74.8   171.5    55.9     40.2     88.4      14.1     x
     H00242   22   M    169.0   76.7   173.8    57.0     38.5     94.2      12.7          x
     H00249   20   M    173.0   78.5   190.3    55.7     37.7     93.8      12.7          x        x



                   Compare responses using G and body weight as factors
                   3 weight groups: 49-52kg (S), 59-67kg (Med), 72-77kg (L)



                                                                                                                   10
                                                                                                      Results: Female Response

                                  5G Mean Head Angular Velocity - Female                                                                                                                   7G Mean Head Angular Velocity - Female

        8                                                                                                                                                        8
        6
                                                                                                                                            Velocity:            6
        4                                                                                                                                                        4
        2                                                                                                                                Fp Med>S, L             2
                                                                                                                                         Xp na
rad/s




                                                                                                                                                         rad/s
        0                                                                                                                                                        0
        -2
        -4
                                                                                                                                         Tp Med>S, L             -2
                                                                                                                                                                 -4
        -6                                                                                                                               TFp Med>S               -6
        -8
                                                                                                                                         TXp S>Med, L            -8
                           0.10


                                         0.19




                                                              0.33


                                                                             0.43


                                                                                           0.52


                                                                                                         0.62
                                                                                                                0.67


                                                                                                                              0.76
             0.00
                    0.05


                                  0.14


                                                0.24
                                                       0.29


                                                                     0.38


                                                                                    0.48


                                                                                                  0.57




                                                                                                                       0.71




                                                                                                                                                                             0.05
                                                                                                                                                                                    0.10
                                                                                                                                                                                           0.14
                                                                                                                                                                                                  0.19
                                                                                                                                                                                                         0.24
                                                                                                                                                                                                                0.29


                                                                                                                                                                                                                              0.38
                                                                                                                                                                                                                                     0.43
                                                                                                                                                                                                                                            0.48
                                                                                                                                                                                                                                                   0.52
                                                                                                                                                                                                                                                          0.57
                                                                                                                                                                                                                                                                 0.62


                                                                                                                                                                                                                                                                               0.71
                                                                                                                                                                                                                                                                                      0.76
                                                                                                                                                                      0.00




                                                                                                                                                                                                                       0.33




                                                                                                                                                                                                                                                                        0.67
                                                                     Time (s)                                                                                                                                                 Time (s)

                                                    Sm Avg               Med Avg               Lg Avg                                                                                                        Sm Avg               Med Avg              Lg Avg


                               5G Mean Head Angular Displacement - Female                                                                                                               7G Mean Head Angular Displacement - Female

        0.8                                                                                                                                                      0.8

        0.6                                                                                                                              Displacement:           0.6

        0.4                                                                                                                              Fp S, Med>L             0.4

                                                                                                                                         TFp Med>L

                                                                                                                                                         rad
rad




        0.2                                                                                                                                                      0.2

             0                                                                                                                                                        0

        -0.2                                                                                                                                                     -0.2

        -0.4                                                                                                                                                     -0.4

                                                                                                                                                                                 0.05




                                                                                                                                                                                                                                  0.39


                                                                                                                                                                                                                                                0.49
                                                                                                                                                                                                                                                       0.54
                                                                                                                                                                                                                                                              0.59
                                                                                                                                                                                                                                                                     0.64
                                                                                                                                                                                                                                                                            0.69
                                                                                                                                                                                                                                                                                   0.74
                 0.00
                        0.05
                               0.10
                                      0.15
                                             0.19
                                                    0.24
                                                           0.29
                                                                  0.34
                                                                          0.39
                                                                                 0.44
                                                                                        0.49
                                                                                               0.53
                                                                                                      0.58
                                                                                                             0.63
                                                                                                                    0.68
                                                                                                                           0.73
                                                                                                                                  0.78




                                                                                                                                                                          0.00


                                                                                                                                                                                        0.10
                                                                                                                                                                                               0.15
                                                                                                                                                                                                      0.20
                                                                                                                                                                                                             0.25
                                                                                                                                                                                                                    0.29
                                                                                                                                                                                                                           0.34


                                                                                                                                                                                                                                         0.44




                                                                                                                                                                                                                                                                                          0.78
                                                                         Time (s)                                                                                                                                             Time (s)

                                                    Sm Avg                Med Avg                 Lg Avg                                                                                                     Sm Avg               Med Avg                 Lg Avg


                                                                                                                                                                                                                                                                                          11
                       Results: Without Matched Groups

                                                                                     G exposures
                                            Head     Neck    Sitting    Neck
                             Wt     Ht     circum   circum   Height    breadth
  SS   Age Gender Wt (lb)   (kg)   (cm)     (cm)     (cm)     (cm)      (cm)     3    4   5    6   7   8   9
H00284 20    F    107.8     48.9   150.8     53.4     30.0    80.4       12.1         x   xx
H00295 23    F    110.0     49.9   157.5      *        *        *         *      x    x   xx   x xx
H00294 19    F    115.0     52.2   152.4      *        *        *         *      x    x   xx   x xx    x   x
H00292 19    F    130.8     59.3   155.4     54.6     33.3    84.7       11.0    x    x   xx   x xx    x   x
H00281 21    F    133.5     60.6   160.4     57.0     33.2    82.5       12.9    x    x   xx   x xx    x
H00289 21    F    147.5     66.9   164.1     56.5     33.0    86.3       11.7    x    x   xx   x x
H00290 19    F    158.0     71.7   167.2     55.8     33.2    86.4       11.5    x    x   xx   x xxx   x   x
H00286 26    F    170.3     77.2   167.4     56.5     35.1    84.7       12.9    x    x   xx   x

H00236   27   M    136.0    61.7   167.3    55.7     34.9     88.5      11.5          x   x                x
H00237   21   M    149.0    67.6   174.9    57.8     37.6     87.7      13.4              xx   x
H00248   18   M    154.0    69.9   177.8    57.9     36.8     92.6      12.9              x
H00227   19   M    160.0    72.6   180.4    56.2     36.0     96.2      12.1     x                         x
H00235   19   M    165.0    74.8   171.5    55.9     40.2     88.4      14.1     x
H00242   22   M    169.0    76.7   173.8    57.0     38.5     94.2      12.7          x
H00249   20   M    173.0    78.5   190.3    55.7     37.7     93.8      12.7          x        x



    Compare responses using G and Gender as Factors: G (3, 4, 5, 6), Gender (8F, 7M)



                                                                                                               12
                                                                                                                                   Results: No Matching

                                             Head Angular Velocity at 4G                                                                                                                                                           Head Angular Velocity at 6G

        8                                                                                                                                                                                8
        6                                                                                                                                                                                6
        4
                                                                                                                                                                   Velocity:             4
        2                                                                                                                                                       Fp M>F                   2




                                                                                                                                                                                rad/s
rad/s




        0                                                                                                                                                                                0
        -2
                                                                                                                                                                Xp na                   -2
        -4                                                                                                                                                      Tp na                   -4
        -6
                                                                                                                                                                TFp M<F                 -6
                                                                                                                                                                                        -8
        -8
                                                                                                                                                                TXp na




                                                                                                                                                                                                      0.05
                                                                                                                                                                                                               0.10
                                                                                                                                                                                                                        0.14
                                                                                                                                                                                                                                 0.19
                                                                                                                                                                                                                                          0.24
                                                                                                                                                                                                                                                   0.29


                                                                                                                                                                                                                                                                     0.38
                                                                                                                                                                                                                                                                              0.43
                                                                                                                                                                                                                                                                                       0.48
                                                                                                                                                                                                                                                                                                0.52
                                                                                                                                                                                                                                                                                                         0.57
                                                                                                                                                                                                                                                                                                                  0.62


                                                                                                                                                                                                                                                                                                                                    0.71
                                                                                                                                                                                                                                                                                                                                             0.76
                                                                                                                                                                                             0.00




                                                                                                                                                                                                                                                            0.33




                                                                                                                                                                                                                                                                                                                           0.67
                    0.05
                           0.10
                                  0.14
                                           0.19
                                                    0.24
                                                             0.29


                                                                               0.38
                                                                                        0.43
                                                                                                 0.48
                                                                                                          0.52
                                                                                                                   0.57
                                                                                                                            0.62


                                                                                                                                              0.71
                                                                                                                                                       0.76
             0.00




                                                                      0.33




                                                                             Time (s)                                                0.67                                                                                                                          Time (s)

              F 49-52kg                  F 59-67kg                     M 62kg                     F 72-77kg                        M 77-79kg                                                             F 49-52kg                        F 59-67kg                     M 68kg                     F 72-77kg                        M 79kg

                                         Head Angular Displacement at 4G                                                                                                                                                       Head Angular Displacement at 6G

         0.8                                                                                                                                                                             0.8
         0.7                                                                                                                                                                             0.7
         0.6                                                                                                                                                                             0.6
         0.5                                                                                                                                                    Displacement:            0.5
         0.4                                                                                                                                                                             0.4
         0.3                                                                                                                                                    Fp na                    0.3
rad




                                                                                                                                                                                rad
         0.2                                                                                                                                                                             0.2
         0.1                                                                                                                                                    TFp M<F                  0.1
           0                                                                                                                                                                               0
        -0.1                                                                                                                                                                            -0.1
        -0.2                                                                                                                                                                            -0.2
        -0.3                                                                                                                                                                            -0.3
               0.00
                      0.05
                             0.10
                                    0.15
                                             0.19
                                                      0.24
                                                               0.29
                                                                        0.34
                                                                                 0.39
                                                                                          0.44
                                                                                                   0.49
                                                                                                            0.53
                                                                                                                     0.58
                                                                                                                              0.63
                                                                                                                                       0.68
                                                                                                                                                0.73
                                                                                                                                                         0.78




                                                                                                                                                                                               0.00
                                                                                                                                                                                                        0.05
                                                                                                                                                                                                                 0.10
                                                                                                                                                                                                                          0.15
                                                                                                                                                                                                                                   0.19
                                                                                                                                                                                                                                            0.24
                                                                                                                                                                                                                                                     0.29
                                                                                                                                                                                                                                                              0.34
                                                                                                                                                                                                                                                                       0.39
                                                                                                                                                                                                                                                                                0.44
                                                                                                                                                                                                                                                                                         0.49
                                                                                                                                                                                                                                                                                                  0.53
                                                                                                                                                                                                                                                                                                           0.58
                                                                                                                                                                                                                                                                                                                    0.63
                                                                                                                                                                                                                                                                                                                             0.68
                                                                                                                                                                                                                                                                                                                                      0.73
                                                                                                                                                                                                                                                                                                                                               0.78
                                                                               Time (s)                                                                                                                                                                              Time (s)

              F 49-52kg                  F 59-67kg                     M 62kg                     F 72-77kg                        M 77-79kg                                                    F 49-52kg                        F 59-67kg                     M 68kg                     F 72-77kg                        M 79kg




                                                                                                                                                                                                                                                                                                                                                13
                              Results: Match Body Weight

                                                                                      G exposures
                                             Head     Neck    Sitting    Neck
                              Wt     Ht     circum   circum   Height    breadth
  SS   Age Gender Wt (lb)    (kg)   (cm)     (cm)     (cm)     (cm)      (cm)     3    4    5   6   7   8   9
H00284 20    F    107.8      48.9   150.8     53.4     30.0    80.4       12.1         x   xx
H00295 23    F    110.0      49.9   157.5      *        *        *         *      x    x   xx   x xx
H00294 19    F    115.0      52.2   152.4      *        *        *         *      x    x   xx   x xx    x   x
H00292 19    F    130.8      59.3   155.4     54.6     33.3    84.7       11.0    x    x   xx   x xx    x   x
H00281 21    F    133.5      60.6   160.4     57.0     33.2    82.5       12.9    x    x   xx   x xx    x
H00289 21    F    147.5      66.9   164.1     56.5     33.0    86.3       11.7    x    x   xx   x  x
H00290 19    F    158.0      71.7   167.2     55.8     33.2    86.4       11.5    x    x   xx   x xxx   x   x
H00286 26    F    170.3      77.2   167.4     56.5     35.1    84.7       12.9    x    x   xx   x

H00236   27   M      136.0   61.7   167.3    55.7     34.9     88.5      11.5          x    x               x
H00237   21   M      149.0   67.6   174.9    57.8     37.6     87.7      13.4              xx   x
H00248   18   M      154.0   69.9   177.8    57.9     36.8     92.6      12.9               x
H00227   19   M      160.0   72.6   180.4    56.2     36.0     96.2      12.1     x                         x
H00235   19   M      165.0   74.8   171.5    55.9     40.2     88.4      14.1     x
H00242   22   M      169.0   76.7   173.8    57.0     38.5     94.2      12.7          x
H00249   20   M      173.0   78.5   190.3    55.7     37.7     93.8      12.7          x        x


                  Match body weight and compare G and Gender as Factors
                  1 (59-68 kg): G (4, 5, 6), Gender (3F, 2M)
                  2 (70-79 kg): G (3, 4, 5, 6), Gender (2F, 5M)

                                                                                                                14
                                                                                         Results: Match Body Weight (59-68kg)

                                                 4G Head Angular Velocity                                                                                                                                           6G Head Angular Velocity

        6                                                                                                                                                                       6

        4                                                                                                                                                  Velocity:            4

        2                                                                                                                                               Fp na                   2




                                                                                                                                                                        rad/s
rad/s




        0
                                                                                                                                                        Xp na                   0

        -2                                                                                                                                                                      -2
                                                                                                                                                        Tp na
        -4                                                                                                                                                                      -4
                                                                                                                                                        TFp M<F
        -6                                                                                                                                                                      -6
                                                                                                                                                        TXp na




                                                                                                                                                                                     0
                                                                                                                                                                                         0.05
                                                                                                                                                                                                0.1


                                                                                                                                                                                                             0.19


                                                                                                                                                                                                                            0.29
                                                                                                                                                                                                                                   0.33
                                                                                                                                                                                                                                          0.38
                                                                                                                                                                                                                                                 0.43
                                                                                                                                                                                                                                                        0.48
                                                                                                                                                                                                                                                               0.52
                                                                                                                                                                                                                                                                      0.57
                                                                                                                                                                                                                                                                             0.62
                                                                                                                                                                                                                                                                                    0.67
                                                                                                                                                                                                                                                                                           0.71
                                                                                                                                                                                                                                                                                                  0.76
                                                                                                                                                                                                      0.14


                                                                                                                                                                                                                     0.24
             0


                            0.1
                 0.05


                                   0.14
                                          0.19
                                                  0.24
                                                         0.29
                                                                0.33
                                                                       0.38
                                                                                  0.43
                                                                                         0.48
                                                                                                  0.52
                                                                                                           0.57
                                                                                                                    0.62
                                                                                                                             0.67
                                                                                                                                      0.71
                                                                                                                                               0.76
                                                                       Time (s)                                                                                                                                                           Time (s)

                                                                   M               AVG F                                                                                                                                              M              AVG F

                                  4G Normalized Head Angular Displacement                                                                                                                             6G Normalized Head Angular Displacement

        0.8                                                                                                                                                                     0.8

        0.6                                                                                                                                                                     0.6

        0.4
                                                                                                                                                        Displacement:           0.4
                                                                                                                                                        Fp na
rad




                                                                                                                                                                        rad
        0.2                                                                                                                                                                     0.2

             0                                                                                                                                          TFp M<F                      0

        -0.2                                                                                                                                                                    -0.2

        -0.4                                                                                                                                                                    -0.4

                                                                                                                                                                                         0


                                                                                                                                                                                                    0.1
                                                                                                                                                                                                          0.15
                                                                                                                                                                                                                 0.2


                                                                                                                                                                                                                               0.29
                                                                                                                                                                                                                                      0.34
                                                                                                                                                                                                                                              0.39


                                                                                                                                                                                                                                                            0.49
                                                                                                                                                                                                                                                                   0.54


                                                                                                                                                                                                                                                                                 0.64
                                                                                                                                                                                                                                                                                        0.69
                                                                                                                                                                                                                                                                                               0.74
                 0
                     0.05
                              0.1


                                            0.2
                                                    0.25


                                                                  0.34
                                                                           0.39


                                                                                           0.49
                                                                                                    0.54


                                                                                                                      0.64
                                                                                                                               0.69
                                                                                                                                        0.74
                                                                                                                                                 0.78




                                                                                                                                                                                             0.05




                                                                                                                                                                                                                        0.25




                                                                                                                                                                                                                                                     0.44




                                                                                                                                                                                                                                                                          0.59




                                                                                                                                                                                                                                                                                                      0.78
                                     0.15




                                                           0.29




                                                                                    0.44




                                                                                                             0.59




                                                                       Time (s)                                                                                                                                                           Time (s)

                                                                       M            AVG F                                                                                                                                                 M          AVG F




                                                                                                                                                                                                                                                                                                         15
                                                                                             Results: Match Body Weight (70-79kg)

                                                    4G Head Angular Velocity                                                                                                                                          6G Head Angular Velocity

        6                                                                                                                                                               6

        4                                                                                                                                                               4
                                                                                                                                                   Velocity:
        2                                                                                                                                                               2
                                                                                                                                                Fp M>F
rad/s




                                                                                                                                                                rad/s
        0                                                                                                                                                               0

        -2
                                                                                                                                                Xp na                   -2

        -4
                                                                                                                                                Tp M>F                  -4

        -6                                                                                                                                      TFp M<F                 -6
             0.00
                    0.05
                           0.10
                                    0.14
                                             0.19
                                                      0.24
                                                              0.29
                                                                      0.33
                                                                              0.38
                                                                                      0.43
                                                                                              0.48
                                                                                                      0.52
                                                                                                             0.57
                                                                                                                    0.62
                                                                                                                           0.67
                                                                                                                                  0.71
                                                                                                                                         0.76




                                                                                                                                                                                                                                                                                        0.62
                                                                                                                                                                             0.00
                                                                                                                                                                                    0.05
                                                                                                                                                                                             0.10
                                                                                                                                                                                                      0.14
                                                                                                                                                                                                               0.19
                                                                                                                                                                                                                        0.24
                                                                                                                                                                                                                                 0.29
                                                                                                                                                                                                                                         0.33
                                                                                                                                                                                                                                                 0.38
                                                                                                                                                                                                                                                         0.43
                                                                                                                                                                                                                                                                 0.48
                                                                                                                                                                                                                                                                         0.52
                                                                                                                                                                                                                                                                                 0.57


                                                                                                                                                                                                                                                                                               0.67
                                                                                                                                                                                                                                                                                                      0.71
                                                                                                                                                                                                                                                                                                             0.76
                                                                                                                                                TXp na
                                                                             Time (s)                                                                                                                                                           Time (s)

                                                                         M             AVG F                                                                                                                                                M              AVG F

                                  4G Normalized Head Angular Displacement                                                                                                                           6G Normalized Head Angular Displacement

         0.7                                                                                                                                                             0.7
         0.6                                                                                                                                                             0.6
         0.5                                                                                                                                                             0.5
         0.4                                                                                                                                    Displacement:            0.4
         0.3                                                                                                                                                             0.3
                                                                                                                                                Fp M>F
rad




                                                                                                                                                                rad
         0.2                                                                                                                                                             0.2
         0.1                                                                                                                                    TFp M<F                  0.1
           0                                                                                                                                                               0
        -0.1                                                                                                                                                            -0.1
        -0.2                                                                                                                                                            -0.2
               0.00
                      0.05
                             0.10
                                      0.14
                                               0.19
                                                       0.24
                                                               0.29
                                                                       0.33
                                                                               0.38
                                                                                       0.43
                                                                                               0.48
                                                                                                      0.52
                                                                                                             0.57
                                                                                                                    0.62
                                                                                                                           0.67
                                                                                                                                  0.71
                                                                                                                                         0.76




                                                                                                                                                                               0.00
                                                                                                                                                                                      0.05
                                                                                                                                                                                               0.10
                                                                                                                                                                                                        0.14
                                                                                                                                                                                                                 0.19
                                                                                                                                                                                                                          0.24
                                                                                                                                                                                                                                  0.29
                                                                                                                                                                                                                                          0.33
                                                                                                                                                                                                                                                  0.38
                                                                                                                                                                                                                                                          0.43
                                                                                                                                                                                                                                                                  0.48
                                                                                                                                                                                                                                                                          0.52
                                                                                                                                                                                                                                                                                 0.57
                                                                                                                                                                                                                                                                                        0.62
                                                                                                                                                                                                                                                                                               0.67
                                                                                                                                                                                                                                                                                                      0.71
                                                                                                                                                                                                                                                                                                             0.76
                                                                              Time (s)                                                                                                                                                           Time (s)

                                                                             M           AVG F                                                                                                                                                  M           AVG F




                                                                                                                                                                                                                                                                                                                16
                        Results: Match Head Circumference

                                                                                     G exposures
                                            Head     Neck    Sitting    Neck
                             Wt     Ht     circum   circum   Height    breadth
  SS   Age Gender Wt (lb)   (kg)   (cm)     (cm)     (cm)     (cm)      (cm)     3    4   5    6   7   8   9
H00284 20    F    107.8     48.9   150.8     53.4     30.0    80.4       12.1         x   xx
H00295 23    F    110.0     49.9   157.5      *        *        *         *      x    x   xx   x xx
H00294 19    F    115.0     52.2   152.4      *        *        *         *      x    x   xx   x xx    x   x
H00292 19    F    130.8     59.3   155.4     54.6     33.3    84.7       11.0    x    x   xx   x xx    x   x
H00281 21    F    133.5     60.6   160.4     57.0     33.2    82.5       12.9    x    x   xx   x xx    x
H00289 21    F    147.5     66.9   164.1     56.5     33.0    86.3       11.7    x    x   xx   x x
H00290 19    F    158.0     71.7   167.2     55.8     33.2    86.4       11.5    x    x   xx   x xxx   x   x
H00286 26    F    170.3     77.2   167.4     56.5     35.1    84.7       12.9    x    x   xx   x

H00236   27   M    136.0    61.7   167.3    55.7     34.9     88.5      11.5          x   x                x
H00249   20   M    173.0    78.5   190.3    55.7     37.7     93.8      12.7          x        x
H00235   19   M    165.0    74.8   171.5    55.9     40.2     88.4      14.1     x
H00227   19   M    160.0    72.6   180.4    56.2     36.0     96.2      12.1     x                         x
H00243   20   M    180.0    81.6   180.0    56.3     36.5     92.1      12.1                       x
H00242   22   M    169.0    76.7   173.8    57.0     38.5     94.2      12.7          x
H00237   21   M    149.0    67.6   174.9    57.8     37.6     87.7      13.4              xx   x
H00248   18   M    154.0    69.9   177.8    57.9     36.8     92.6      12.9              x


     Match head circumference (55.7-56.5cm) and compare G and Gender as Factors
     G (3, 4, 5, 6, 7, 9), Gender (3F, 5M)


                                                                                                               17
                                                                                    Results: Match Head Circumference

                                            4G Mean Head Angular Velocity                                                                                                                              9G Mean Head Angular Velocity

        15                                                                                                                                                        15

        10
                                                                                                                                             Velocity:            10

          5                                                                                                                               Fp M>F                   5




                                                                                                                                                          rad/s
rad/s




          0                                                                                                                               Xp na                    0

         -5                                                                                                                               Tp M>F                   -5

        -10                                                                                                                               TFp M<F                 -10
                                     0.15




                                                                  0.34




                                                                                                0.53
              0.00
                      0.05
                              0.10


                                             0.19
                                                    0.24
                                                           0.29


                                                                          0.39
                                                                                 0.44
                                                                                        0.49


                                                                                                       0.58
                                                                                                              0.63
                                                                                                                     0.68
                                                                                                                            0.73
                                                                                                                                   0.78




                                                                                                                                                                        0.00


                                                                                                                                                                                            0.10
                                                                                                                                                                                                    0.15
                                                                                                                                                                                                             0.20
                                                                                                                                                                                                                      0.25
                                                                                                                                                                                                                               0.29
                                                                                                                                                                                                                                        0.34
                                                                                                                                                                                                                                                0.39
                                                                                                                                                                                                                                                        0.44
                                                                                                                                                                                                                                                                 0.49
                                                                                                                                                                                                                                                                          0.54
                                                                                                                                                                                                                                                                                  0.59
                                                                                                                                                                                                                                                                                          0.64
                                                                                                                                                                                                                                                                                                   0.69
                                                                                                                                                                                                                                                                                                           0.74
                                                                                                                                                                                                                                                                                                                   0.78
                                                                                                                                                                                   0.05
                                                                                                                                          TXp na
                                                                         Time (s)                                                                                                                                                          Time (s)

                                                                  AVG M                 AVG F                                                                                                                                            AVG M                     F

                             4G Mean Normalized Head Angular Displacement                                                                                                             9G Mean Normalized Head Angular Displacement

          1                                                                                                                                                             1
        0.8                                                                                                                                                        0.8
        0.6
                                                                                                                                          Displacement:            0.6
        0.4                                                                                                                                                        0.4
                                                                                                                                          Fp M>F
rad




                                                                                                                                                           rad
        0.2                                                                                                                                                        0.2
          0                                                                                                                               TFp na                        0
        -0.2                                                                                                                                                      -0.2
        -0.4                                                                                                                                                      -0.4
               0.00
                      0.05


                                     0.15
                                             0.20
                                                    0.25
                                                           0.29
                                                                   0.34
                                                                          0.39
                                                                                 0.44
                                                                                         0.49
                                                                                                0.54
                                                                                                       0.59
                                                                                                              0.64
                                                                                                                     0.69
                                                                                                                            0.74
                                                                                                                                   0.78
                              0.10




                                                                                                                                                                            0.00
                                                                                                                                                                                     0.05
                                                                                                                                                                                             0.10
                                                                                                                                                                                                      0.15
                                                                                                                                                                                                               0.20
                                                                                                                                                                                                                        0.25
                                                                                                                                                                                                                                 0.29
                                                                                                                                                                                                                                         0.34
                                                                                                                                                                                                                                                 0.39
                                                                                                                                                                                                                                                          0.44
                                                                                                                                                                                                                                                                   0.49
                                                                                                                                                                                                                                                                           0.54
                                                                                                                                                                                                                                                                                   0.59
                                                                                                                                                                                                                                                                                            0.64
                                                                                                                                                                                                                                                                                                    0.69
                                                                                                                                                                                                                                                                                                            0.74
                                                                                                                                                                                                                                                                                                                     0.78
                                                                         Time (s)                                                                                                                                                              Time (s)

                                                                  AVG M                 AVG F                                                                                                                                         AVG M                    AVG F




                                                                                                                                                                                                                                                                                                                     18
                                     Discussion
Limitations:
• Few male datasets available with same acceleration pulse profile – previous studies used
  higher onset (see Paskoff presentation at 2:00 PM this afternoon)
• Sufficient subjects to match for anthropometrics
     • Missing female anthropometrics
• Starting head position not uniform

Summary:
• Kinematic response varies with Gz
• Individual subject variation; however, similar pattern in head motion
• Body size a factor in female head response
     • Medium weight class: greater peak motion but slower rise time
• Without matching, at 3 to 6 Gz, male head flexion greater (velocity) and faster (velocity &
  displacement) than female
• Match for body weight:
     • Lighter group demonstrated difference in time to peak flexion (4 to 6 Gz)
    • Heavier group: male head motion greater and faster (vel & displ) (3 to 6 Gz) than female
• Match for head circumference (3, 4, 5, 6, 7, 9 Gz)
     • Male head motion greater (vel & displ) and faster TFp than female
                                                                                                 19
                                    Next


• Characterize linear displacement
• Continue to mine BDR for additional datasets for comparable G onset male
  response data
• Compare horizontal to vertical sled +Gz kinematic responses



                           Acknowledgments

• NBDL volunteers
• NAMRL
   • Carl Cole, Dottie Dubuisson, Dan Thomas, Angus Rupert, David Street
• NAVAIR
   • James Sheehy, PhD



                                                                             20

				
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