Evaluation and Management of Foot and Ankle Disorders Present

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					                                            Journal of Orthopaedic & Sports Physical Therapy
                                            Official Publication of the Orthopaedic and Sports Physical Therapy Sections of the American Physical Therapy Association

 Evaluation and Management of Foot and Ankle
 Disorders: Present problems and Future
Thomas G. McPoil, PhD, PT, ATC        '
Gary C. Hunt, MA, PT, OCS *

                                                        Recent research has raised serious concerns regarding the reliability and validity of the
                                                evaluation and treatment scheme proposed by Root et al. Although the Root et a1 theory is widely
                                                referenced in the physical therapy literature and commonly taught in continuing education courses,
                                                current issues of concern include: I ) measurement technique reliability, 2) the criteria proposed for
                                                normal foot alignment, and 3) the position of the subtalar joint behveen midstance and heel-off
                                                during walking. The intent of this paper is to review these three problem areas which have been
                                                identified with the Root et a1 theory as well as to propose the use of a "tissue stress model" which
                                                the authors have found to be an effective alternative for evaluating and treating foot disorders.
Thomas G. McPoil       Gary C. Hunt             Key Words: foot, orthopaedics, management
                                                 Associate Professor; Co-Director, Gait Research Laboratory; Department of Physical Therapy, Northem
               he theory proposed by                                                           AZ
                                                Arizona University, P.O. Box 15 105, Flagstaff, 860 1 1
               Root et al for the evalua-        Clinical Faculty, Southwest Baptist University, Bolivar, MO; Senior Therapist, Springfield Physical Therapy
               tion and treatment of            and Hand Rehabilitation Center, Springfield, M O
               foot and ankle disorders
               has gained increased
popularity among physical therapists            titioners, the medical community                           termed these abnormal variations
over the past 15 years. This degree of          tended to look at the foot as a static,                    from normal foot alignment as "in-
popularity can be illustrated by the            nonmoving structure. The primary                           trinsic foot deformities" and classified
fact that of the 21 clinical and re-            focus of treatment consisted of evalu-                     them as a forefoot varus, forefoot
search manuscripts regarding foot               ating the height of the medial longi-                      valps, and rearfoot varus (13,14).
biomechanics or the utilization of              tudinal arch and using a navicular                         Root et al noted that these intrinsic
foot orthoses published in Physical             pad to maintain the arch in a "nor-                        deformities would cause abnormal or
 Therapy or ThP Journal o Orthopaedic
                           f                    mal" position, while the patient was                       excessive foot motion, which could
a n d Sports Physical Therapy between           standing in a static posture. Root et                      lead to foot and lower extremity dis-
1988 and 1993. 70% directly refer-              al emphasized the importance of                            orders (13).
enced the writings of Root et al. Fur-          looking at the foot as a dynamic,                               The protocol proposed by Root
thermore, the Root et al approach               moving structure and designed a new                        et al for treating these intrinsic foot
has been the basis for numerous                 paradigm for the management of                             deformities included the following
physical therapy continuing educa-              foot disorders with that philosophy in                     steps: 1)determine if an "intrinsic
tion courses, focusing on the man-              mind.                                                      deformity" is present, 2) measure the
agement of foot and ankle disorders.                 The basis for the Root et al a p                      amount of the deformity using a go-
      The philosophy and theory advo-           proach was the classification of a b                       niometer, 3) cast the patient's foot to
cated by Root et al for evaluating and          normal foot types. In order to classify                    capture the degree of deformity in a
treating foot disorders was a dramatic          abnormal foot types, Root et al de-                        plaster model, and 4) construct a
change from the previous manage-                fined what they termed the ideal or                        "functional" foot orthoses. The func-
ment approaches utilized by the med-            "normal" foot alignment, as well as                        tional foot orthoses, as described by
ical community. Up until the time               several variations from this normal                        Root et al, was fabricated with wedges
that Root et al presented their man-            foot alignment which could cause                           or posts, which were positioned in
agement theories to health care prac-           abnormal foot function ( 1 3,14). They                     either the forefoot or rearfoot de-

JOSFT Volume 21 Number 6 June 1995
FOOT/ANKLE            THERAPY        &        RESEARCH

pending on the classification of foot          neutral position between midstance        to propose the use of a "tissue stress"
deformity. The functional foot ortho-          and heel-off during walking.              model for consideration by the
ses would act to prevent abnormal or                One can easily see the paradox       reader as a basis for developing an
excessive foot motion.                         that can face the clinician when us-      evaluation and management para-
     The cornerstone of Root et al's           ing the Root et al approach. If the       digm for treating individuals with
management paradigm was their defi-            clinician suspects that their patient     foot disorders.
nition of the typical or "normal" foot         has a foot disorder caused by exces-
alignment, since deviations from this          sive foot pronation, in order to treat    DISCUSSION OF PROBLEM AREAS
alignment were classified as abnor-            the patient using the model pro-
mal. The foot was defined as being in          posed by Root et al, the clinician        Reliability of the Measurement
normal alignment when: I ) the bisec-          must find an intrinsic deformity in       Procedures
tor of the calcaneus was in line or            their examination in order to p r o p
parallel with the bisector of the lower        erly post the foot orthoses. What if           Several studies have been con-
one-third of the leg, and 2) the plane         the patient had no intrinsic defor-       ducted by physical therapists which
of all five metatarsal heads were per-         mity, but has a combined femoral          have examined the reliability of the
pendicular to the calcaneal bisector           torsion and tibia1 valgum deformity       procedures described by Root et al to
                                               which is causing the excessive foot       measure both subtalar joint range of
                                               pronation? Under the Root et al clas-     motion as well as the magnitude of
                                               sification scheme, the therapist could    foot deformity. Elveru et al studied
      The validity of the                      not wedge or post a foot orthoses for     the issue of interrater and intrarater
                                               these common lower extremity defor-       reliability of measurements of the
     theory proposed by                        mities. Moreover, as with any exami-      subtalar joint neutral position, as well
    Root et a1 was based                       nation procedure, treatment, or mo-
                                               dality used by health practitioners,
                                                                                         as subtalar joint passive range of mo-
                                                                                         tion (3). In their study, the involved
     on their belief that                      the theory as well as the techniques      feet of 43 patients with neurologic
                                               necessary to implement the theory         and orthopaedic disorders were eval-
   normal foot alignment                       should be both valid and reliable. If     uated by 14 different therapists with
     occurred when the                         intrinsic deformities were thought to
                                               be present during the examination,
                                                                                         a range of clinical experience. The
                                                                                         therapists were asked to measure the
   subtalar joint and the                      could the measurement techniques          subtalar joint position and passive
                                               described by Root et al be used by        range of motion measurements. The
    foot were in neutral                       the clinician to provide a reliable as-   findings of their investigation indi-
      position between                         sessment of the deformity so that a
                                               proper classification could consis-
                                                                                         cated that intratester reliability was
                                                                                         fairly high, but that intertester mea-
   midstance and heel-off                      tently be made? Finally and most im-      surement reliability among the 14
                                               portantly, is the basis for the foot      therapists was extremely poor. They
       during walking.                         classification scheme proposed by         concluded that with the exception of
                                               Root et al valid?                         ankle plantar flexion, measurements
                                                    Recently, the results of several     of subtalar joint neutral position and
(14). Root et al specifically noted            research studies have raised concerns     passive range of motion could not be
that this normal foot alignment oc-            regarding the evaluation and treat-       considered reliable among therapists.
curred only when the subtalar joint            ment scheme proposed by Root et al.            Lattanza et a1 (7) evaluated non-
was positioned in neutral and the              These issues have been focused on:        weight-bearing and weight-bearing
midtarsal joint fully locked (13).             1) the reliability of the measurement     measurements of subtalar eversion
Thus, normal foot alignment, which             techniques described by Root et al to     position. In their study, a single eval-
was stated to occur between mid-               measure both normal and abnormal          uator performed all meawrements
stance and heel-off during walking,            foot alignment; 2) the criteria for       on the right lower extremity of 17
was the criteria for determining fore-         normal foot alignment; and 3) the         healthy subjects, and neutral position
foot or rearfoot deformities in Root           proposed fact that the subtalar joint     of the subtalar joint was determined
et al's scheme for evaluating and              and the foot are in neutral position      through the palpation method. The
treating the foot (13). The validity of        between midstance and heel-off dur-       results of this investigation indicated
the theory proposed by Root et al              ing walking.                              that subtalar joint eversion range of
was based on their belief that normal     '
                                                    The intent of this paper is to re-   motion was significantly greater in
foot alignment occurred when the               view these three areas of concern         the weight-bearing position as com-
subtalar joint and the foot were in            with the Root et al method, as well as    pared with the nonweight-bearing

                                                                                              Volume 21 Number 6 June 1995 JOSPT
                                                                         FOOT/ANKLE            THERAPY         &   RESEARCH

 position. They further concluded that        position and movement should be              ple of the general population using
 the practitioner needs to evaluate the       taken in a weight-bearing position           the criteria for normal foot structure
 patient in a weight-bearing position,        and not in a nonweight-bearing posi-         proposed by Root et al, a normal or
since this is the functional position in      tion. A major problem with weight-           Gaussian distribution would be ex-
which activities of daily living are car-     bearing measurements of forefoot             pected. In other words, the middle
 ried out.                                    deformities was noted by McPoil et al        portion of the standard normal distri-
      Smith-Oricchio and Harris (15)           (11 ) when evaluating three different       bution, which is in the shape of a
 evaluated the interrater reliability of      methods of casting the foot in subta-        bellshaped curve, would be com-
 positioning the subtalar joint in neu-       lar neutral position. They reported          posed of individuals who have a nor-
 tral position as well as measuring cal-      that forefoot varus and valgus defor-        mal foot alignment and stand with
caneal inversion and eversion range           mities could not be replicated when          their subtalar joints in a neutral posi-
of motion. Three physical therapists          the plaster cast of the foot was ob-         tion. As previously noted, Root et al
with several years of clinical experi-        tained in a weight-bearing position in       described that the normal foot align-
ence performed the measurements               comparison with a nonweight-bearing          ment occurred when the bisector of
and determined the position of s u b          position.                                    the lower leg was in line or parallel
 talar neutral on the involved ankles               Based on these studies, it would       with the calcaneal bisector and that
of 20 patients. Subtalar neutral posi-        appear that physical therapists would        the plane of the metatarsal heads was
tion was determined by using both             not be able to agree among them-             perpendicular to the calcaneal bisec-
the mathematical method and palpa-            selves on measurements of subtalar           tor (14). They further noted that
tion in the prone position. Calcaneal        joint neutral position as well as pas-        normal foot alignment could only
inversion and eversion were mea-              sive range of motion of the subtalar         occur when the subtalar joint was
sured both weight bearing and non-           joint. Diamond et a1 (2) did report a         positioned in neutral and when the
weight bearing. The results of their          relatively high degree of interrater         midtarsal joint was locked by converg-
study indicated that nonweight-bear-          reliability between two therapists           ing the axes of the midtarsal joint.
ing measurements of calcaneal inver-          measuring subtalar joint range of mo-        Based on these criteria, the clinician
sion and eversion and subtalar joint          tion in a group of diabetic patients.        should expect that 68% of the popu-
neutral position had low to moderate          However, they noted that to obtain                     1
                                                                                           lation (t SD) should fall within the
interrater reliability. However, weight-      this high interrater reliability, lengthy    middle portion of the distribution
bearing measurements of calcaneal             training sessions were required over         and, thus, have a normal foot align-
position were found to have a higher          an 18month period with constant              ment. In evaluating the feei of 20 s u b
interrater reliability. Their results also    discussion between the two therapists       jects, Smith-Oricchio and Hams (15)
indicated that while the palpation            "defining and agreeing on common             found that only 3 or 15% of the s u b
method of determining subtalar neu-           techniques of measurement." While           jects actually stood with their feet in
tral position had a higher reliability        Diamond et al were able to demon-            the subtalar neutral position. They
value than the mathematical method,          strate that a relatively high level of        also discussed the need for further
neither method achieved a high level          interrater reliability could be o h          research to determine if the normal
of interrater reliability for use with a      tained between two therapists who            population stands with their subtalar
patient population. The authors also         were in constant communication, as           joints positioned in neutral. McPoil
made an interesting clinical observa-        well as willing to work together in           et al (10) conducted a study in which
tion by noting that although the neu-        order to come to an agreement in              they determined the degree of fore-
tral position of the subtalar joint is       regard to their measurement tech-             foot and rearfoot deformity in 58
thought to be the desired position of        niques, this may not be practical in          healthy, young females. Of the 1 16
the foot, only three of their subjects       the typical practice setting for most         feet included in the survey, 8.6% had
stood with the subtalar joint in neu-        physical therapists.                          a forefoot varus deformity, 44.8%
tral position.                                                                             had a forefoot valps deformity, and
      The results of these studies indi-     Criteria for Normal Foot Alignment            14.7% had a plantar flexed first ray.
cate that the physical therapist can                                                       Subtalar varus was present in 83.6%
expect a low level of interrater reli-              The second issue is whether the        of the sample, while tibiofibular va-
ability when performing measure-              normal foot alignment proposed by            rum was present in 98.3% of the p o p
ments of subtalar joint neutral posi-         Root et al is applicable to the general      ulation studied. Only 17% of the 116
tion and calcaneal or subtalar range          population. In other words, does the         feet that were evaluated had a "nor-
of motion. This is despite acceptable         Root et al theory have external valid-       mal" foot alignment. All of the s u b
intrarater reliability. Furthermore, it       ity. If an examination of foot align-       jects included in the McPoil et al
would appear, based on these studies,         ment, as described by Root et al, was        study had no previous history of or-
that measurements of subtalar joint          'performed on a representative sam-           thopaedic or neurological impair

JOSPT Volume 21 Number 6 June 1995
 -    T/ NKL
                              E --
F O O-.-- A ----..-*-E -- T-H... R A P Y
                                             -.    -
                                                  R E S E A R-,-. H ---.-..----------...-.--
                                                    -.- .--   P

 ment of either lower extremity. An-                  (14). They further noted that neutral     from the definition of "neutral subta-
 other interesting finding of their                  position of the subtalar joint occurs      lar joint position" proposed by Root
 study was that 18 or 31% of the sub-                at approximately 50 and 65% of the         et al. Wright et a1 (16). however, are
jects in the study were found to have                stance phase (14). Root et al (13)         the only objective data referenced by
 a different forefoot and/or rearfoot                defined subtalar joint neutral posi-       Root et al to substantiate their theory
 classification bilaterally. It would a p            tion as when the subtalar joint was        of normal rearfoot motion.
 pear, based on the results of these                 neither pronated or supinated.                  McPoil and Cornwall (9), in an
 studies, that the incidence of a nor-                    As previously noted, a major is-      attempt to determine whether neu-
 mal foot alignment is extremely                     sue of discussion is whether the sub-      tral position of the subtalar joint did
 small. This leads one to question                   talar joint is in a neutral position       occur between midstance and heel-
whether the criteria for normal foot                 during the period of midstance. The        off in the walking cycle, evaluated the
 alignment defined by Root et al is                  theoretical normal foot alignment,         rearfoot motion pattern in both feet
 too stringent to apply to the general               which serves as the criteria for deter-    of 50 healthy, asymptomatic subjects.
 population.                                         mining whether a patient has a nor-        Each subject was filmed using two-
      Finally, Root et a1 (14) noted in              mal or abnormal foot alignment, is         dimensional videography while they
 their text on evaluation that the dis-              based on the concept that neutral          walked over a 12-m walkway three
 tal one-third of the lower leg should               position of the subtalar joint occurs      times for each extremity. After the
 be perpendicular to the floor. McPoil               at or just after midstance during          walking trials were completed, each
 et al (12), in evaluating the degree of             walking. In order for the clinician to     subject was filmed while they stood in
 tibiofibular varum in 58 subjects us-               even consider evaluating and treating      their resting calcaneal stance position
 ing both clinical and radiographic                  intrinsic foot deformities, the issue of   (standing in a relaxed posture) as
 measurements, found that all subjects               whether the neutral position of the        well as in their neutral calcaneal
 had between 4.6 to 8.7" of tibiofibu-               subtalar joint occurs between mid-         stance position (standing with the
lar varum. These findings would also                 stance and heel-off during walking in      subtalar joints in neutral position).
suggest that the criteria for normal                 the general population should be           Rearfoot motion and static positions
foot alignment proposed by Root et                   substantiated.                             were then digitized and calculated
al is too restrictive when applied to                     Root et al (14) based their de-       for both the left and right feet. Each
                                                     scription of normal foot motion on a       foot was considered as an individual
 the general population.
                                                     study conducted by Wright et al (16)       structure, so 100 feet were evaluated.
                                                     in 1964. Wright et al used potentiom-      Based on the results of their study,
Position of Subtalar Joint During                    eters aligned to the subtalar and tale     McPoil and Cornwall (9) described
Walking                                              crural joint axes to determine the         the typical pattern of rearfoot motion
                                                    joint motion pattern in only two sub-       as follows:
      The last and most important is-               jects. Their results indicated that the        1. The rearfoot was slightly inverted
 sue relates to validity of the theory               two subjects tested reached a "neu-              prior to heel strike.
 proposed by Root et al, notably, does               tral" position at approximately 65 to         2. From heel strike to foot flat, the
 the subtalar joint attain a neutral p e             70% of the stance phase. While this              rearfoot undergoes the motion of
 sition between midstance and heel-off               is in agreement with Root et al, a               eversion, with the average per-
 during the walking cycle. Root et al                critical point is the criteria that              cent time to maximum rearfoot
 (13) proposed a motion pattern for                  Wright et al used to defined subtalar            eversion being approximately
 the foot in which they described                   joint neutral position in their study.            40% of stance phase for the 100
 movement of the subtalar joint                      Wright et al defined "neutral" posi-             feet.
 throughout stance. They noted that                  tion of the subtalar joint as when            3. The motion of rearfoot inversion
 prior to heel strike, the subtalar joint            their subjects were: 1 ) standing re-            was initiated after 50% of stance
 was inverted secondary to contraction               laxed with knees fully extended,                 phase and continued until toe-
 of the pretibial group. From heel                   2) arms at their sides, 3) feet 6 inches         off.
 strike to foot flat, the subtalar joint             apart, and 4) a comfortable amount            4. The "neutral position" for the
 underwent the motion of pronation                   of toeing out. This placement of the             typical rearfoot motion pattern
 and remained in a pronated position.                subject would be more comparable                 was resting calcaneal stance posi-
 From the end of foot flat to toe-off,              with what Root et al (14) described               tion and not neutral calcaneal
 the subtalar joint undergoes the mo-                as relaxed calcaneal stance position             stance position.
 tion of supination. A critical point is             rather than neutral calcaneal stance            The results of the McPoil and
 that Root et al specifically stated that            position. Thus, the definition of neu-     Cornwall study are in agreement with
 slightly before heel-off, the subtalar              tral subtalar joint position described     the values reported by Wright et al.
joint would be in a neutral position                 by Wright et al is completely different    Unfortunately, these findings severely

                                                                                                     Volume 21 Number 6 June 1995 JOSPT
challenge the validity of the theory       TISSUE S R S MODEL AS A BASIS
                                                   TES                               ment as the foot is loaded and un-
proposed by Root et al.                    F R EVALUATION
                                            O                                        loaded. As long as the individual
     These inherent problems with                                                    maintains the level of tissue stress
the Root et al approach may be one              In the consideration of the prob-    within the elastic region, tissue inita-
of the reasons why two recent re-          lems noted with the evaluation and        tion and inflammation will most
search papers in Physical Therapy,         treatment scheme proposed by Root         likely be maintained at a tolerable
which used the Root et al approach         et al, the authors have chosen to use     level, with overuse injury avoided. If,
for both evaluating their subjects and     a tissue stress model as the basis for    however, the individual's level of ac-
fabricating foot orthoses, consistently    developing an examination and the         tivity or the magnitude of the load
"undercorrected" the actual amount         management paradigm for treating          applied to the tissues of the foot are
of forefoot deformity that they mea-       individuals with foot disorders. While    increased, tissues could be deformed
sured on their subjects (4,6). On a        the tissue stress model is by no          beyond the microfailure zone and
more important note, why would the         means a novel idea, it has permitted      into the plastic range resulting in an
clinician even bother to perform the       the authors to develop an examina-        overuse injury. It is important to rec-
evaluation protocol described by           tion and management protocol which        ognize that individuals will have their
Root et al if it has no validity? The      is based on the same logic used for       own level of tolerance for the
most obvious answer would be to ex-        other body articulations and to not       amount of tissue stress that can be
amine the patient's foot structure         focus on the use of unreliable mea-       withstood during walking as well as
and classify the alignment as normal                                                 other activities of daily living.
or abnormal. Unfortunately, the pre-                                                      The examination and manage-
vious discussion has indicated that        - --                                      ment scheme using the tissue stress
severe problems exist in the reliabil-
ity and validity of the measurement            Individuals will have                 model would include:
                                                                                        Step 1: Identifying the tissues being
procedures required to classify the
patient's foot structure. Another im-
                                                 their own level of                              excessively stressed based on
                                                                                                 the history, symptoms, and
portant reason for performing the                 tolerance for the                              other subjective information
measurement procedures could be to
predict whether the patient has an            amount of tissue stress                            provide by the patient;
                                                                                        Step 2: The application of con-
excessive foot pronation or supina-
tion pattern of movement during
                                              that can be withstood                              trolled stresses to tissues
                                                                                                 identified in Step 1 through
walking. Investigations, however, by          during walking as well                             the application of weight-
both Hamill et al (5) and McPoil and
Cornwall (8) have demonstrated the             as other activities of                            bearing and nonweight-
                                                                                                 bearing tests, as well as pal-
inability to predict dynamic motion                  daily living.                               pation, range of motion,
of the rearfoot during walking when
using the static foot evaluation proce-
                                           .-         -- --                                      a n d muscle f u n c t i o n /
dures as described by Root et al.                                                                strength assessment;
     The authors strongly believe that,    surement techniques. Furthermore,            Step 3: Based on the evaluative find-
given the present state of health care     the tissue stress model provides the                  ings, determine if the etiol-
reform and the need to substantiate        physical therapist with a rationale for               ogy of the patient's com-
the efticacy of treatment, the physical    the use of nonphysical therapy inter-                 p l a i n t is secondary t o
therapist is challenged to develop         ventions, such as footwear and foot                   excessive mechanical load-
sound and cost-effective management        orthoses, in their management pro-                    ing; and
techniques for the treatment of foot       gram.                                        Step 4: Institute a management pro-
disorders. If the reliability and valid-        The tissue stress model can be                   tocol which emphasizes: A)
ity of the Root et al approach is ques-    illustrated using the loaddeformation                 reducing tissue stress to a
tionable and researchers have deter-       curve (1). The loaddeformation                        tolerable level through rest,
mined that static measurements of          curve consists of two regions or                      footwear, and foot orthoses;
the foot and ankle have no value in        zones: an elastic region and a plastic                B) healing the involved tis-
predicting dynamic foot motion, then       region (Figure 1). The area separat-                  sues using modalities and
the physical therapist must begin to       ing the elastic and plastic regions is                soft tissue mobility tech-
question whether they should con-          considered the microfailure zone.                     niques; and C) the restora-
tinue to utilize the evaluation and        The elastic region represents the nor-                tion of flexibility and muscle
treatment scheme proposed by Root          mal "give-and-take" of soft tissues                   strength to permit the re-
et al.                                     which prevents excessive joint move-                  sumption of daily activities.

JOSPT Volume 21 Number 6 June 1995
                Elastic Region                       ,          Plastic Region                                        and does not start again until after 3
                                                                                                                      to 4 hours of constant walking or
                                                                                                                      standing. She further reported that if
                                                                                                                      she sat down to rest, when she stood
                                                                                                                      again, she had the same type of heel
                                                                                                                      pain that occurred first thing in the
                                                                                                                      morning upon rising. When asked to
                   Microfailure                                                                                       point to the region of the heel that
                                                                                                                      hurts, she did not point directly to
                                                                                                                      the bottom of the heel but to an area
                                                                                                                      anterior and medial to the bottom of
                                                                                                                      the heel. She stated that she had no
                                                                                                                      other problems or symptoms. She was
                                                                                                                      prescribed an oral anti-inflammatory
                                                                                                                      medication by her physician. She
                                                                                                                      stated that this was the first time that

point on the curve.
                          Deformation (mm)                                     -
FIGURE 1. The loaddefonnation curve. It should be noted that the divisions illustrated in the graph represent a
generalization. The microfailure zone is shown to begin at the end of the elastic region, but can occur before this
                                                                                                                      she ever had pain in her feet. When
                                                                                                                      the footwear that she used for work
                                                                                                                      was inspected, they were found to be
                                                                                                                      extremely worn as well as poor fit-
                                                                                                                           Comment A key point in the his-
                                                                                                                      tory for this patient was the increase
                                                                                                                      in activity associated with the onset of
                                                                                                                      symptoms as well as the reporting of
                                                                                                                      pain upon weight bearing after a pe-
     The "tissue stresswmodel allows                        CASE STUDY ILLUSTRATING THE                               riod of nonweight bearing. Based on
the clinician the flexibility to adapt                      APPLICATION OF THE TISSUE                                 the history provided, it would appear
their evaluation and treatment proce-                                                                                 that the patient has overstressed her
                                                            STRESS MODEL
dures based on the identification of                                                                                  plantar fascia, resulting in tissue in-
those tissues which are inflamed or                                                                                   flammation.
                                                            Step 1. History and Identification of
injured secondary to excessive me-                          Stressed Tissues
chanical loading. Palpation, special                                                                                  Step 2. Application of Controlled
tests to stress soft tissues, the assess-                        The patient was a 29-year-old fe-                    Stresses to Involved Tissues
ment of range of motion, and the                            male college student, referred to
determination of muscle strength                            physical therapy by her family physi-                          The patient was first asked to
would be included in a comprehen-                           cian, who stated that she had pain in                     stand so that her lower extremity and
sive evaluation scheme to determine                         her left heel region for the past 2                       foot alignment could be inspected. A
the level and magnitude of tissue in-                       months. The results of the radie                          moderate genu valgum was noted
flammation and the resulting limita-                        graphic examination were negative.                        bilaterally, and the patient was
tion in movement. Furthermore, in                           She stated that the symptoms began                        slightly overweight. The combination
the proposed tissue stress model,                           approximately 1 week after she                            of the lower leg alignment and the
footwear and foot orthoses would be                         started working as a waitress, which                      increased body weight caused exces-
used as a means to rest overstressed                        required standing on her feet for 10                      sive foot pronation. The patient was
tissues. Thus, foot orthoses would be                       to 12 hours per day, 5 days a week.                       then asked to walk approximately 15
a small part of the entire treatment                        Prior to starting her job as a waitress,                  feet independently. She demon-
plan rather than the entire emphasis                        she stated that she primarily sat at a                    strated a slightly antalgic gait with a
of treatment. To illustrate the clinical                    computer terminal entering data.                          minimal decrease in weight bearing
                                                            The patient stated that the pain had                      on the left foot. The patient was then
application of the tissue stress model,
                                                            become increasingly worse over the                        asked to long sit on a plinth with the
the following case study of a patient
                                                            past 4 weeks and that she has severe                      feet over the edge. Passive range of
diagnosed with overuse induced plan-
                                                            heel pain upon standing first thing in                    motion of the subtalar joint and mid-
tar fasciitis will be described.
                                                            the morning. After 20-30 minutes of                       tarsal articulations were within nor-
                                                            activity, the pain begins to resolve                      mal limits and pain free with over-

                                                                                                                           Volume 21 Number 6 June 1995 JOSFT
                                                                       FOOT/ANKLE           THERAPY &          RESEARCH

 pressure toward eversion. First            tar fascia during the tissue healing        recurrence of the plantar fasciitis.
 metatarsophalangeal joint extension,       stage, the need for prolonged utiliza-      This would include exercises to main-
 measured with the talocrural joint in      tion of foot orthoses may not be nec-       tain soft tissue mobility to prevent
 neutral, was within normal limits and      essary.                                     contracture of the plantar fascia and,
 pain free with over-pressure. The pa-                                                  thus, restricted extension range of
 tient reported marked discomfort           Step 4. Management Program                  motion of the first metatarsophalan-
 when the anterior-medial aspect of                                                     geal joint. In addition, strengthening
 the plantar surface of the left calca-          A. To reduce the level of stress in    exercises of the intrinsic and extrin-
 neus was palpated with slight to mod-      the plantar fascia to a tolerable level,    sic muscles of the involved lower leg
 erate pressure. The patient was then       the patient would be asked to: 1) pos-      and foot must be implemented to
 asked to stand and the first metatar-      sibly modify her existing work sched-       provide dynamic stabilization of the
 sophalangeal joint was passively ex-       ule to decrease the number of con-         joints of the foot. Since the patient
 tended to observe the windlass effect      secutive hours worked so that she can      was somewhat overweight, a recom-
 of the plantar fascia. The patient re-     reduce the amount of stress applied         mendation could be made for her to
 ported only slight discomfort after        to the involved tissues; 2) purchase        see a dietitian regarding a weight-
 approximately 45" of extension.            footwear with cushioned midsoles,           control program.
      Comment The intent of the             leather uppers with at least 5 to 6              While the intent of this hypothet-
 above evaluation was to stress those       eyelets, and a firm heel counter to         ical case presentation is to illustrate
 tissues identified in Step 1. In this      assist in controlling excessive foot        the use of the tissue stress model as
 case, the patient's complaints of dis-     pronation; and 3) be fitted with tem-       the basis for planning the evaluation
 comfort were all associated with in-       porary over-the-counter foot orthoses       and management of foot disorders, it
 creased stress applied to the plantar      or have her foot strapped with adhe-        by no means represents a complete
 fascia in both weight-bearing and          sive tape to control the amount of          management program. The use of
 nonweight-bearing positions. Range         foot pronation.                             this model would require constant
 of motion of first metatarsophalan-             Comment The use of the foot            modification based on each patient's
 geal joint extension was within nor-       orthoses or adhesive strapping in the       complaints and symptoms. It does,
                                            treatment program for this patient          however, provide an example of how
 mal limits, indicating that plantar
                                            should begin immediately, before the        the physical therapist can treat foot
 fascia mobility was not restricted. Re-
                                            start of any other treatment, to re-        and ankle disorders without having
 stricted first metatarsophalangeal
                                            duce the level of stress to the plantar     to struggle to classify an individual's
joint extension is often observed in
                                            fascia. Hopefully, as the tissue inflam-   foot structure using measurements
 cases of intractable plantar fasciitis.
                                            mation and associated pain are re-         which are unreliable, quite possibly
                                            duced, the foot onhoses can be re-          invalid, and are of no use in predict-
Step 3. Assessment of Patient's             moved. As previously mentioned, it is       ing functional foot movement.
Complaint                                   important to issue the patient tempo-
                                            rary foot orthoses to control foot mo-     SUMMARY
     Based on the evaluative findings,      tion immediately before the start of
the etiology of the patient's plantar       any other treatment. It makes no                It is not the authors' intent to
fasciitis is excessive mechanical load-     sense to give the patient a series of      suggest that the "tissue stress" model
ing leading to an inordinate amount         modalities or other treatments to aid      described is the only method that
of tissue stress to the plantar aponeu-     in healing inflamed tissues without        should be used to examine and man-
rosis. The primary cause of the exces-      limiting the excessive foot motion         age foot and ankle disorders. That
sive mechanical stress to the plantar       which is contributing to the in-           would be whimsical at best. It is, how-
aponeurosis is the change in the level      creased stress of the plantar fascia.      ever, the authors' hope that this
of activity associated with the patient's        B. Once the amount of tissue          model will provide the start of a con-
new job with a secondary cause being        stress is controlled through the use of    tinual dialogue among physical thera-
excessive foot pronation.                   either temporary foot orthoses or          pists to determine the optimal meth-
     Comment It is important to re-         adhesive strapping, then various treat-    ods for managing patients referred
member that the patient has always          ments intended to provide symptom-         with foot disorders. Until we as a pro-
had the excessive foot pronation, but       atic relief, including modalities, soft    fession are willing to recognize the
no history of foot problems until           tissue mobilization, and massage,          problems associated with the current
changing jobs. Thus, while the use of       would be initiated.                        treatment theories utilized in our
foot orthoses to control her excessive           C. Once symptoms are resolved,        clinics, we will not be able to leave
foot pronation is required immedi-          the next stage of the management           these unfounded treatment a p
ately to reduce the stress to the plan-     program would be started to prevent        proaches behind us and begin the

JOSPT Volume 21 Number 6 June 1995
FOOT/ANKLE               THERAPY            &     RESEARCH

process of developing sound and s u b                  patellofemoral pain syndrome. Phys                between the ages of 18 to 30 years. J
stantiated protocols for the manage-                   Ther 73:62- 68, 1993                              Orthop Sports Phys Ther 9:406-409,
                                                    5. Hamill 1, Bates BT, Knutzen KM, Kirk-              1988
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                                                       patrick GM: Relationship between se-        11.   McPoil TG, Schuit D, Knecht HG: A
can we expect to receive the respect                   lected static and dynamic lower ex-               comparison of thr& neutral foot im-
and recognition as legitimate provid-                  tremity measures. Clin Biomech 4:2 17-            pression procedures in women 19 to 30
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only other health care providers, but               6. Johanson MA, Donatelli R, Wooden            12.   McPoil TG, Schuit 0, Knecht HG: A
also from the health care insurers of                  MJ, Andrew PD, Cummings G: Effects                comparison of three positions used to
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                                                    7. Lattanza L, Gray GW, Kanmer RM:                   and Abnormal Function of the Foot
                                                       C l o d versus open kinematic chain               (Volume 2), Los Angeles, CA: Clinical
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                                                                                                          Volume 21 Number 6 June 1995 JOSPT