DOUGLAS S. CREIGHTON, PT, BS,t VARICK L. OLSON, PT, PhD*

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1 /87/ $02.00/0 THE JOURNAL OF ORTHOPAEDIC AN0 SPORTS PHYSICAL THERAPY Copyright by The Orthopaedic and Sports Physical Therapy Sections of the American Physical Therapy Association Evaluation of Range of Motion of the First Metatarsophalangeal Joint in Runners with Plantar Faciitis* DOUGLAS S. CREIGHTON, PT, BS,t VARICK L. OLSON, PT, PhD* Accurate assessment of range of motion of the first metatarsophalangeal joint may assist the physical therapist when dealing with plantar fasciitis. The purpose of this study was to determine whether there is any difference in the amount of flexion and/ or extension at the first metatarsophalangeal joint in runners with plantar fasciitis. Bilateral active and passive range of motion values at the first metatarsophalangeal joint were measured with a goniometer on six subjects with plantar fasciitis and six subjects without the pathology while their leg was stabilized at the ankle and forefoot in an adapted orthosis. The results indicate a statistically significant decrease in active extension, passive extension, and passive flexion in runners with plantar fasciitis. Due to the loss of stability in the medial longitudinal arch which accompanies decreased extension range of motion at the first rnetatarsophalangeal joint, specific evaluation of this joint is needed when the physical therapist is treating a patient with plantar fasciitis. Accurate assessment of joint range of motion allows the physical therapist to estimate the efficacy of treatment, evaluate progress, determine an end point for therapy, or evaluate the degree of residual disability at the discontinuation of treatment. One joint for which motion is not often measured is that of the first metatarsophalangeal joint (MTP). Assessment of range of motion of the first MTP joint may assist the therapist when dealing with persons suffering from foot pain. Hicks' researched the mechanism whereby there is elevation of the medial longitudinal arch of the foot with passive extension of the first MTP joint by virtue of the attachment of the plantar aponeurosis to the proximal phalanx and the calcaneum. Mann and Hagy4 support this finding, and state, as the toes progressively dorsiflex throughout the stance phase of gait there is elevation and subsequent stabilization of the medial longitudinal arch without the function of muscles, but rather a tethering action of the plantar apo- 'This work was completed at Oakland University as part of Mr. Creighton's requirements for the B.S. in Physical Therapy degree in Subjects t Douglas Creighton, PT, BS, Kendallwood Drive, Farmington Hills. MI S Director of Physical Therapy. Oakland University, Rochester, MI neurosis. Mann and Hagy4 further state that the plantar aponeurosis is most functional at the great toe and becomes progressively less functional at the lesser toes. They also indicate that at the time of toe-off, 70-90' of extension is achieved at the metatarsophalangeal joints. Restricted motion of the first MTP joint may alter the mechanical ability of the plantar aponeurosis to. tighten, elevate, and stabilize the medial longitudinal arch of the foot. This loss of stability in the medial longitudinal arch may predispose the foot to injury and pain. The loss of medial arch stability may be related to a number of biomechanical factors such as excessive pronation during the stance phase of gait, extreme foot types such as the cavus or planus foot, and continual repetitive forces which have been associated with plantar fa~ciitis.~ The purpose of this study was to evaluate the amount of active and passive range of motion (ROM) of flexion and extension of the first MTP joint in subjects (runners) with and without plantar fasciitis. Nine men and three women with a mean height of & 10.3 cm, weight of kg,

2 358 CREIGHTON AND OLSON JOSPT Vol. 8, No. 7 Fig. 1. Placement of the subject's lower extremity.in the adapted orthosis. Fig. 2. Placement of the moveable toe plate at the sutjlect's first metatarsophalangeal joint line. and age of years volunteered as subjects. The study consisted of two groups. Group one was comprised of six subjects (runners) who ran a mean distance of 25 miles per week and were not experiencing any foot pain. Group two was comprised of six subjects (runners) who ran a mean distance of 23.6 miles per week. Criteria for inclusion into this group included a diagnosis of plantar fasciitis which was currently limiting their training. Procedure + The equipment used for this study was a standard international goniometer, and an adapted ankle-foot orthosis. This adapted orthosis was set at 90 and attached to it were three velcro closure straps which stabilized the subject's leg, ankle, and forefoot (Fig. 1). The toe plate was movable at %-inch intervals along the plantar surface of the foot. The %-inch intervals provided direct stabilization at the first MTP joint line for each subject (Fig. 2). This study was conducted during the months of January through April. The time of year is stressed as it was somewhat difficult to find acute cases of plantar fasciitis during the winter months and therefore chronic cases were used. Prior to data collection, each subject filled out a questionnaire in which they listed their height, weight, age, distance run per week, and whether or not they were diagnosed with plantar fasciitis. Each subject was instructed to lie supine on a treatment table. The left and right first MTP joint lines were identified using a Kaltenborn2 anteroposterior mobilization technique. Each joint line was marked with a pen. The movable toe plate was positioned at the first MTP joint line, and the

3 JOSPT January 1987 RUNNERS WITH PLANTAR FASCllTlS 359 Fig. 3. Goniometric measurement of active metatarsophalangeal extension Fig. 4. Goniometric measurement of passive metatarsophalangeal extension. left leg, ankle and forefoot were strapped into the adapted orthosis. The 0-90' scale on a standard international goniometer was used to measure the range of motion at the first MTP joint. The goniometer was placed on the medial aspect of the foot with its axis aligned with the MTP joint axis. The stationary arm was parallel to the floor, and the moving arm was parallel to the proximal phalanx of the great toe (Fig. 3). The subjects were instructed to perform three trials of maximal active MTP flexion and three trials of maximal active MTP extension. Each trial was measured, recorded, and the mean of the three trials was used for data analysis. This was followed by three trials of passive MTP flexion and extension. The passive force was applied to the proximal and distal phalanx of the subject's great toe through the examiner's second finger while at the same time the aforementioned placement of the goniometer was maintained (Fig. 4). Again, each trial was measured, recorded, and the mean of the three trials was used for data analysis. Each subject was repositioned and the

4 same procedure was carried out for the right first MTP joint. To test the reliability of the investigator to obtain the ROM measurements a test-retest method was used. Range of motion measures were obtained on three subjects who were not affected with plantar fasciitis or included in either group 1 or group 2. Range of motion measures were obtained again 2 weeks later. Analysis The range of motion measurements were analyzed, and the means, standard deviations, and t- tests at the 0.05 level of significance were calculated for active flexion, active extension, passive flexion, and passive extension. The test-retest measurements were compared by determining the difference between the two measurements and calculating the mean of the difference. RESULTS The reliability values showed consistency of the measurer's goniometric accuracy, as the mean differences were: active flexion = 3.3', passive flexion = 1.5O, active extension = 2.4', passive extension = 4.0. The means and standard deviations for each measurement taken on the left and right first MTP joint in subjects without plantar fasciitis are presented in Table 1. Table 2 lists the means and standard deviations for both the involved and uninvolved first MTP joint in subjects with plantar fasciitis. TABLE 1 Means and standard deviations for the ROM (degree) at the first MTP joint in subjects without plantar fasciitis (N = 6) Left Right X SD X SD Active flexion Active extension Passive flexion Passive extension TABLE 2 Means and standard deviations for the ROM (degree) at the first MTP joint in subjects with plantar fasciitis (N = 6) Involved Uninvolved - X SD - X SD Active flexion Active extension Passive flexion Passive extension AND OLSON JOSPT Vol. 8, No. 7 TABLE 3 Results of t-test comparing the combined ROM (degree) at the first MTP joint in subjects without plantar fasciitis (N = 12) and the involved MTP joint of subjects with plantar fasciitis (N = 6) - X (N = 12) X (N = 6) S pooled t stat.' Active flexion Active extension Passive flexion Passive extension 't = 0.05: df16 = Group 1 and group 2 range of motion measures were compared using a t-test. Inasmuch as the right and left ROM measures (Table 1) for the group without plantar fasciitis were very close, the right and left measures were combined for an N of 12. This in turn provided an increased number of degrees of freedom for the t-test. The results of the t-test indicate significant difference of passive flexion and extension and active extension (Table 3) with the runners with plantar fasciitis having reduced range of motion. DISCUSSION Rothstein et al5 and Low3 speak of the importance of proper stabilization, consistent placement of the goniometer axis, and greater accuracy when only one individual is pefforming all of the goniometric measurements. All of these criteria have been met, and the results of the reliability test-retest study showed good consistency of measurement. The results of this study indicate a significant decrease in active and passive extension as well as passive flexion of the first MTP joint in runners with plantar fasciitis. Our findings indicate a decrease of 16.3O of active extension, and a decrease of 22.3' of passive extension in those subjects with plantar fasciitis. The question arises, did the runners have a decreased ROM of the first MTP prior to suffering plantar fasciitis? If they did have a predisposing decreased ROM, would ROM exercise or mobilization treatment of the first MTP have prevented disabling plantar fasciitis? Further research with a larger sample size appears warranted. CONCLUSION Based on the findings of this research as well as the work of Hicks,' physical therapists should direct their attention to evaluation of the first MTP joint when dealing with individuals suffering from

5 JOSPT January 1987 RUNNERS WITH PLANTAR FASCllTlS 361 plantar fasciitis. In addition, evaluation of the first MTP joint ROM should become standard procedure when performing a prerunner's evaluation. If reduced ROM in extension, which appears to be associated with the occurrence of plantar fasciitis, does indeed affect the stability of the medial longitudinal arch, perhaps various therapeutic measures aimed at restoring this limited range may positively influence the course of this pathology or prevent it. REFERENCES 1. Hicks JH: The plantar aponeurosis and the arch. J Anat 88:25-31, Kaltenborn FM: Mobilization of the Extremity Joints, Ed 3. Oslo: Olaf Norlis Bokmandel Low JL: The reliability of joint measurement. Physiotherapy 62: Mann RA, Hagy JL: The function of the toes in walking, jogging, and running. Clin Orthopaed~cs 142: Rothste~n JM, Miller PJ, Roettger RF: Goniometric reliability in a clinical setting. Phys Ther 63: , Roy S: How I manage plantar fasciitis. Phys Sportsmed 11: , 1983