The Ankle Joint Definition of Ankle Motions Definition of Ankle

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The Ankle Joint Definition of Ankle Motions Definition of Ankle Powered By Docstoc
					                                          2006 NATA Annual Meeting
                                          Atlanta, GA

                                                                             The “Ankle” Joint
                                                                             Widely viewed as a single joint

            Evaluation and Management                                        Actually a series of joints that
                                                                             are highly integrated
            of Subtalar Joint Dysfunction                                      Inferior Tibio-Fibular Syndemosis
                    Gary Wilkerson, EdD, ATC                                   Talocrural Joint
                                                                               Subtalar Joint
                                                                               Transverse Tarsal Joint
                                                                               Tarsometatarsal Joints
                                                                               Metatarsophalangeal Joints


Definition of Ankle Motions                                                  Definition of Ankle Motions
1) In relation to orthogonal cardinal planes
       Axis of motion assumed ⊥ to plane of motion                            Sagittal Plane
           Where do planes/axes intersect?                                       Plantar Flexion – Dorsiflexion

       One segment assumed to be stationary
           Are planes/axes fixed in relation to position of stationary        Frontal Plane
           segment? Horizontal and vertical?                                     Abduction – Adduction?
                                                                                 Inversion – Eversion
                                                                                 Supination – Pronation

                                                                              Transverse Plane
                                                                                 Internal Rotation – External Rotation
                                                                                 Adduction – Adduction?
                                                                                    Foot moving on fixed leg?
                                                                                    Leg moving on fixed foot?

                                                                         3                                               4

Definition of Ankle Motions                                          Definition of Ankle Motions
2)    Motion of moving (usually distal) segment in relation to
      stationary adjacent (usually proximal) segment                   Simultaneous motion of both segments?
        Foot motion in relation to fixed leg?                             Motion defined in relation to adjacent segment?
           Open-Chain (Foot Inv-Evr OR Sup-Pro?)                          Motion defined in relation to vertical or horizontal
        Leg motion in relation to fixed foot?                             reference lines?
           Closed-Chain (Leg Inv-Evr OR Abd-Add?)                            Leg Angle + Foot Angle = Pronation Angle

             MEDIAL                                 LATERAL

                                                                 5                                                               6

     Functional Axis of Subtalar Joint                               Definition of Ankle Motions
                                                                     3) In relation to direction of movement around a
                                                                        functional axis
     Functions like “mitred hinge”                                         Definition not dependent on position of adjacent
        Rotation of segments in opposite directions                        segment or vertical/horizontal reference planes
        Simultaneous motion in all 3 cardinal planes

                                                                 7                                                               8

Definition of Ankle Motions                              Definition of Ankle Motions
 Inversion – Eversion                                     Supination – Pronation
  1) Commonly use to describe “open-chain”                1) Commonly used to define foot alignment
     motion of foot in relation to leg.                      under weightbearing “closed-chain” condition.
  2) Almost exclusively used to describe acute            2) Commonly used to describe foot position
     ankle injury mechanism.                                 during different phases of gait cycle.

                                                    9                                                        10

Definition of Ankle Motions                              Talocrural Joint
Triplanar Displacement
                                                          “Upper Ankle Joint”
  Combined Sagittal + Transverse + Frontal
  motions associated with subtalar joint function
    Podiatry Definition
       Supination = PF + Adduction + Inversion
       Pronation = DF + Abduction + Eversion

    Orthopedic Definition
       Inversion = PF + Adduction + Supination
       Eversion = DF + Abduction + Pronation

                                                    11                                                       12

Inferior Tibio-Fibular Syndesmosis        Talus
                                          Key structure between leg & foot
                                          Function similar to of ball bearing
                                            No muscle attachments
                                            Almost completely covered with articular cartilage

                                     13                                                          14

Talocrural Articular Surfaces             Functional Axis of Talocrural Joint

                                     15                                                          16

Functional Axis of Talocrural Joint                   Ankle Ligaments - ATFL

                                                 17                            18

Subtalar Joint                                        Subtalar Joint:
 “Lower Ankle Joint” – Talo-Calcaneal Joint           Calcaneus + Talus
   Part of Talo-Calcaneo-Navicular (TCN) Joint

                                                 19                            20

Functional Axis of Subtalar Joint                    Subtalar Tri-planar Motion
                                                                  Frontal Plane Component
                                                                    Supination or Inversion

                                                21                                            22

Functional Axis of Subtalar Joint                    Integrated TC + ST Function
Functions like “mitred hinge”
  Rotation of segments in opposite directions                            Composite
                                                                         TC/ST Axis
  Frontal Plane + Transverse Plane

                                                23                                            24

Transverse Tarsal Joint                           Transverse Tarsal Joint
     Transitional link
        Rearfoot – Forefoot                      1) Oblique axis (OTT)
        S-shaped joint line                           Motion in same direction as that of ST joint
                                                 2) Longitudinal axis (LTT)
                                                      Motion in direction opposite to that of ST joint



                                            25                                                           26

Transverse Tarsal Joint                           Mid-Foot Ligaments
                                                      Bifurcated Ligament


        Tarsal Joint

                                            27                                                           28

                                                    Tarsometatarsal Joints
Mid-Foot Ligaments
                                                       Collective function similar to that of
                                                       Transverse Tarsal Joint

                                                                                    Axis of
                                                                                                 Axis of
                                                                                    1st Ray      5th Ray

                                                   Axis of
                                                   1st Ray

                                                                          Axis of     Subtalar
                                            29                            5th Ray       Axis               30

Metatarsophalangeal Joints                       Integrated Function of Foot/Ankle Joints
 Integrated function of the 5 MTP joints           Weight-bearing heel elevation produces
 represented by composite functional axis          hindfoot inversion
     greater extension of medial joints
     greater extension of lateral joints

                                            31                                                             32

   Integrated Function of Foot/Ankle Joints                Heel Elevation – Hindfoot Inversion
      Composite hindfoot axis
          parallel to MTP axis

                                                      33                                                    34

   Muscle Actions: Eversion/Inversion                      Ankle/Foot Biomechanics
                                                            Forefoot, Rearfoot, & Leg mechanically linked

Lateral to ST Axis:

                                 Medial to ST Axis:

                                                      35                                                    36

                                                            Conventional View of Pronation
Pronation-Related Conditions
                                                             Focus on rearfoot
   Plantar Faciitis
   Medial Tibial Stress Syndrome                               Orientation of calcaneus in relation to leg
                                                                 valgus position
   Posterior Tibialis Tendinitis
   Achilles Tendinitis                                         Status of longitudinal arch
   Metatarsal Stress Fracture                                    navicular height

   Patello-Femoral Syndrome
                                                               Position of talus relative to calcaneus
   ACL Rupture                                                   “subtalar neutral”

                                                       37                                                    38

                                                            Frontal Plane Component of
   Pronation: Integrated Joint Motions                      Subtalar Tri-planar Motion
1) Calcaneal Eversion (Valgus)

2) Internal Rotation + Lateral Deviation Of Leg

3) Plantar Flexion + Internal Rotation Of Talar Head

4) Compensatory Forefoot Supination (Varus)
     Rearfoot Pronation (Subtalar Joint)
     Forefoot Supination (Transverse Tarsal Joint)


Pronation assessment tends to
be focused on position of foot in                             Pes Planus:
relation to horizontal support                                Plantar Flexion + Internal Rotation
                                                              of Head of Talus on Calcaneus

            Foot Angle
            Leg Angle

Leg segment does not remain
stationary in a vertical orientation                                    Associated with “Navicular Drop”
during functional activities!!!

    Gait Cycle                                                   Abnormal Pronation
    Heelstrike → Mid-Stance → Toe-Off
                                                                  Max pronation occurring beyond 25% of
    Heelstrike to Mid-Stance
                                                                  stance phase (walking)
       Supination to Pronation
           joint mobility
                                                                    Diminished propulsive capability
           shock absorption
                                                                    Prolonged & excessive loads on tissues
    Mid-Stance to Toe-Off                                           Improper timing of pronation may be more
       Pronation to Supination                                      problematic than magnitude of pronation
           joint surfaces locked
           foot becomes rigid lever                                 May be due to deficiency in invertor
                                                                    strength/endurance (posterior tibialis)
           force transfer from Achilles tendon to toes
                                                         43                                                    44

                                            Posterior Tibialis Tendon
                                          Primary insertion on navicular tuberosity
                                          Dynamic stabilizer of medial longitudinal arch
                                            Subjected to great mechanical stress
                                               Eccentric action: Heel strike to mid-stance
                                                   Deceleration of pronation
                                               Concentric action: Mid-stance to push-off
                                                   Supination of foot (increased rigidity)

                                            Longitudinal tears
                                            Complete rupture

    Posterior Tibialis Role in             Posterior Tibialis Test
                                           Diminished capability to elevate heel, combined
    Transfer of Force from
                                           with lack of hindfoot supination
    Rearfoot to Forefoot



                                                 NORMAL                                      48

  Excessive Pronation                                         Forefoot-Hindfoot Twist
1) Tibia + talus internally rotated                           Forefoot relation to horizontal support surface: Neutral
                                                              Forefoot relation to hindfoot: Supinated (varus position)
2) Navicular + forefoot externally rotated
      Forefoot abduction in relation to rearfoot

                                                                           Forefoot -
                                                                           Hindfoot                    Hindfoot
                                                                            Neutral                    Pronation

                                                         Tendency for
                                                        Lateral Lift-Off

                                                   49                                                                     50

                                                           Fabrication of Thermoplastic Orthotics


Fabrication of Thermoplastic Orthotics        Fabrication of Thermoplastic Orthotics

                                         53                                                                   54

Fabrication of Thermoplastic Orthotics        Chronic Ankle Dysfunction
                                                10% to 50% of all lateral ankle sprains
                                                  Repetitive reinjury

                                                                    Isakov et al, Int J Sport Biomech, 1986
                                                                    Karlsson & Lansinger, Clin Orthop, 1992
                                                                    Konradsen et al, Foot Ankle, 1991
                                                                    Peters et al, Foot Ankle, 1991
                                                                    Smith & Reischl, AJSM, 1986
                                         55                                                                   56

                                                     MRI Studies:
Chronic Ankle Dysfunction                            Ankle Pathology
                                                 Clinicians often underestimate
1) Undiagnosed subtalar pathology?               severity of ankle ligament damage
                                                      Frey: FAI, 1996
                                                         Initial diagnosis vs. MRI results

2) Inadequate compensation for rotary
   instability?                                  Subtalar ligaments are often
                                                 damaged by inversion injury
                                                      Togichi et al: FAI, 1998
                                                         > 50% of lateral ankle sprain cases

                                        57                                                                       58

 Subtalar Pathology                                  Subtalar Joint:
   Lateral Talocalcaneal Ligament
                                                     Lateral Pain/Instability
   Interosseus Talocalcaneal Ligament
                                                              Sinus Tarsi Syndrome
                                                                  Abnormality of one or more structures within
   Cervical Ligament                                              sinus tarsi or tarsal canal
                                                                  Feeling of hindfoot instability
                                                                  Responsive to injection of local anesthetic
                                             Sinus                    Trauma: 70% of cases
                                             Tarsi                    Insidious inflammation: 30% of cases
                                                                           Ankylosing spondylitis
                                                                           Rheumatoid arthritis
                                                                           Ganglion cyst
                                                                           Foot deformity

                                        59                                                                       60

     Sinus Tarsi                                                                                      Subtalar Pathology
          Separates anterior & posterior articulations
          of subtalar joint                                                                            Lateral Talocalcaneal Ligament
                                                                                                       Inferior Peroneal Retinaculum
          Contents:                          Sinus
                                             Tarsi                                                     Inferior Extensor Retinaculum - Lateral Root
               Fat, nerves, arteries
               Joint capsules (anterior & posterior)
               ITFL & CL
               Inferior Extensor Retinaculum “Roots”

                                                                                                                        Inf. Per. Ret.
                                                                                                 61    LTCL                              Inf. Ext. Ret.   62

                         Subtalar Joint Ligaments                                                              Lateral Ankle Sprain
                                                   Ant.Band                 Ligament
                                                  Post Band

                                                                                       Inf Ext Ret

                                                               Plantar                 ITCL
                    Ant.Band                                  Calcaneo-             Ant. Band
        Post Band                                             Navicular
                                   Ant.Band                   Ligament        Capsule of
                                      Post Band                           Post ST Articulation

Post Band = Capsule of
 Post ST Articulation

                                                                                                 63                                                       64

                              Talocrural PF:
VGRF Medial to ST Axis
                              ST Axis Orientation

                         65                              66

                              Typical Mechanism of LAS



                         67                              68

Forefoot – Rearfoot Torque Transfer        Subtalar Inversion +
                                           External Leg Rotation

                                      69                                                                  70

                                             Frontal Plane Lateral Talar Tilt
 Locked Joints = Rigid Lever                Excessive talar tilt associated with ATFL damage

                                              Widely viewed as a component of the ATFL injury mechanism

                                              Support systems designed to restrict frontal plane motion

                                      71                                                                  72

                                                                        Simplistic View of Ankle Sprain
Talar Tilt vs. Rotary Subluxation                                           Mechanism of Injury
 ATFL critical role: restraint of
 transverse plane rotation

   Cass & Settles: FA, 1994
   Colville et al: AJSM,1990
   Hintermann: MSSE, 1999
   Johnson & Markolf: JBJS(A), 1983
   McCullough & Burge: JBJS(B), 1980
   Parlasca et al: Clin Orthop, 1979
   Rasmussen & Tovborg: Acta Orthop Scand, 1981
   Renstrom et al: FA, 1988
   Stormont et al: AJSM, 1985
                                                               73                                                 74

Ankle Taping
                                                                    Lateral Subtalar Sling
 Stirrup strips & heel locks
                                                                    High-strength semi-elastic tape
   Encasing hindfoot probably resists lateral distraction of          1 or 2 strips oriented at 45º in sagittal
   joint surfaces within the frontal plane                            plane & wrapped around leg

                                                                      spans all joints between forefoot & leg

                                                                         4th & 5th Tarsometatarsal Joints
                                                                         Transverse Tarsal Joint
                                                                         Subtalar Joint
                                                                         Talocrural Joint

                                                               75                                                 76

Lateral Subtalar Sling                                                                   Lateral Subtalar Sling
                                                                                              ER of leg generates tension within
 Tension generated within longitudinal fibers of tape                                         longitudinal fibers of tape
   Vertical component resists frontal plane motion of foot                                       restrains INV of lateral border of foot
   A-P component resists anterior translation of talus (anterior drawer)                         restrains IR of talus in relation to leg ER

                                                                                    77                                                                78

   Subtalar Joint Ligaments
                              Intermediate       Cervical                                  Lateral Subtalar Sling
                                  Root -         Ligament
                              Inf. Ext. Ret.                Ext.Dig.
           Ant. Articular Surface                            Brevis                          Wilkerson: AJSM, 1991
             Medial Root -
             Inf. Ext. Ret
                                                                                               Standard: Gibney/Heel-Locks
                                                                   Lateral Root -              Modified: Gibney/Heel-Locks + Lateral Subtalar Sling
                                                                   Inf. Ext. Ret.
                                                                                                  2 - 3 hours of football practice

          Interosseus                          Posterior
         Talo-Calcaneal                        Articular
           Ligament                             Surface

                                                                 Capsule of
                                                                   ST Axis

 Wilkerson: AJSM, 1991
                                                                                  Ankle Capsule: Normal vs. Distended
    Post-ex INV restraint increased 94%
       Untaped INV: 40º
       Tape residual restriction: 8.5º vs 16.5º

                     8.5º        16.5º

                                              Sagittal: 9.56 Nm (7 ft lbs)
                                              Frontal: 6.67 Nm (5 ft lbs)

                                                                             81                                          82

ATFL-Capsule Compaction                                                           Antero-Lateral Impingement
                                                                                  Edema proteins absorbed by synovium
                                                                                  Chronic inflammatory response
                                                                                    Synovial hypertrophy
                                                                                    Development of extensive adhesions
                                                                                    Fibrous scarring of synovium
                                                                                    Hyalinization of lesion
                                                                                    Chondromalacia of talus

                                                                             83                                          84

Ankle Impingement Syndrome                                             Medial Subtalar Sling
                                                                        Support of medial longitudinal arch
                                                                        Restraint of subtalar eversion
                                                                                Decreased Antero-Lateral Impingement
                                                                                Decreased load on Posterior Tibialis
                                                                                Protection of Deltoid Ligament
                                                                                Protection of Tibio-Fibular Syndesmosis

                                                                 85                                                                     86

  Subtalar Sling: Mechanical Effect                                   Antero-Posterior Displacement (mm)
  Wilkerson G, Kovaleski J, Meyer M, Stawitz C
                    6 degree of freedom arthrometer                    125 N (28 lb) anterior-posterior force
                       23 physically active subjects                   Significant Trial X Method interaction (p <.001)
                           12 males & 11 females
                           No history of ankle dysfunction
                       Standard taping vs. modified taping
                           Modified: medial + lateral ST sling                                       16


                                                                          Estimated Marginal Means


                                                                                                     8                              2
                                                                                                       1          2           3
                                                                                                     Untaped   Taped      Untaped
                                                                                                       TRIAL   Post-Ex    Post-Ex
                                                                 87                                                                     88

                                                                    Measurement of
Advantages of Taping                                                Inversion Velocity &
 Improved Joint Position Sense                                      Leg External Rotation

 Peroneal Facilitation

 Inversion Deceleration
                                                                                            3X greater restraint
                                                                                            of Max ER
 Restriction of Max Subtalar Motion
                                                                                            2X greater reduction
 Control of Anterior Drawer                                                                 of Avg Inv Velocity

                                                                                            2X greater reduction
 Restraint of Anterolateral Rotary Instability?                                             of Peak Inv Velocity

                                                               89                                                  90

Advantages of Bracing                                                   Effect?

                              Ease of Application

                              Improved Joint Position Sense

                              Inversion Deceleration

                              Restriction of Max Inversion

                              Restriction of Leg Rotation???          45°


Ankle Brace Designs                                    Measurement of Leg External Rotation

Articulated Stirrup

Lace-Up Ankle Gauntlet
(with or without straps)


                                                                     No Brace: 11.7 ±3.9
                                                  93                                          94

Measurement of Leg Rotation                            Summary


                                                       Downloadable PDF file of slides:
     10.7 ±4.2         11.5 ±4.6
                                              → “Program News”

 9.9 ±3.1         11.4 ±3.8            8.5 ±3.1

                 No Brace: 11.7 ±3.9
                                                  95                                          96