Participants performed strengthening exercises progressively longer each time for up to 3 sets of 30 repetitions twice daily by the third visit. Exercises included bilateral heel raises, foot adduction/rear foot inversion with thera-tubing, and unilateral heel raises. Participants increased resistance by using thera-bands with higher levels of resistance over the 12 week period. The amount of resistance was progressed according to patient tolerance at each visit. Strengthening exercises were preceded by the control stretching exercises which constituted a "warm up."

Subjects were provided with written descriptions and pictures demonstrating 2 range-of-motion exercises which included a wall calf stretch, and a supine ankle active range-of-motion exercise. Subjects were instructed to perform 3 sets of the stretching exercises, 2 times a day, similar to the intervention group. Each stretching exercise was performed twice and held for 30 seconds.

A force transducer (Model SML-200, Interface, Scottsdale, AZ) was connected in series with a resistance plate and oscilloscope (TDS 410A, Tektronix, Beaverton, OR) to display force readings. Participants were seated with their leg in an an air stirrup brace (Aircast, Inc.) mounted on uprights. The air stirrup brace was adjusted so the heel was approximately 10 cm above the resistance plate, resulting in 30 to 45 degrees of ankle plantar flexion depending on foot length. The resistance plate was mounted on ball bearing tracks in the medial/lateral direction and moleskin was used to fit to the general shape of the medial forefoot. The result was that participants could exert maximum effort against the resistance plate (medial direction) with little discomfort. This testing position essentially replicates the manual muscle test position for the posterior tibialis muscle. Force in Newtons was then divided by body mass in kilograms to calculate normalized strength (N/Kg).

Total of all reporting groups

A 3 dimensional foot kinematic model including the tibia, calcaneus (hindfoot), 1st metatarsal, 2-4th metatarsals and hallux was used to measure foot movement. Six infrared cameras (Optotrak Motion Analysis System, Northern Digital Inc, CAN), synchronized with force plate data (Model 9286, Kistler, Switzerland), were used to collect kinematics (60 Hz) and force (1000 Hz) data with the Motion Monitor software Version 7.24 (Motion Monitor, Innsport Training Inc, USA). Anatomically based coordinate systems were established for each segment using digitized boney landmarks consistent with a previous study. Kinematic data were smoothed using a 4th order, zero phase lag, Butterworth filter with a cut off frequency of 6 Hz. To calculate relative joint angles a Cardan angle Z-X-Y sequence of rotations was used as suggested by Cole et al. The range of possible values varies for each individual and each joint.

The Short Musculoskeletal Function Assessment Questionnaire (SMFA) is a 46 item self-report questionnaire consisting of the Dysfunction Index, which has thirty-four items, and the Bother index which has 12 items. The Dysfunction index is used for assessment of patient perceptions of functional performance while the Bother index is used to assess patients' perceptions of the degree patients are bothered in broad areas such as recreation and leisure. The responsiveness to change of the SMFA is 10 points out a range of 100 for each scale (Dysfunction, Mobility, and Bother indexes). The SMFA is also particularly suitable for the current investigation due to the presence of a sub-category of questions from the Dysfunction Index that pertains specifically to mobility (i.e. Mobility Index). Lower scores (lowest = 0) indicate better function, mobility, and that patients are less bothered while higher scores (highest = 100) indicate worse function, mobility and that patients are bothered.

A force transducer (Model SML-200, Interface, Scottsdale, AZ) was connected in series with a resistance plate and oscilloscope (TDS 410A, Tektronix, Beaverton, OR) to display force readings. Participants were seated with their leg in an an air stirrup brace (Aircast, Inc.) mounted on uprights. The air stirrup brace was adjusted so the heel was approximately 10 cm above the resistance plate, resulting in 30 to 45 degrees of ankle plantar flexion depending on foot length. The resistance plate was mounted on ball bearing tracks in the medial/lateral direction and moleskin was used to fit to the general shape of the medial forefoot. The result was that participants could exert maximum effort against the resistance plate (medial direction) with little discomfort. This testing position essentially replicates the manual muscle test position for the posterior tibialis muscle. Force in Newtons was then divided by body mass in kilograms to calculate normalized strength (N/Kg).

Participants in Group B will undergo bracing and perform stretching and strengthening exercises.