• Foot function index [ Time Frame: Measured at Weeks 1, 6, and 12 ] [ Designated as safety issue: No ]
  

• Foot kinematics and posterior tibial muscle length (estimated from foot kinematics) [ Time Frame: Measured at baseline and Weeks 6 and 12 ] [ Designated as safety issue: No ]
  

Posterior tibial tendon dysfunction (PTTD) involves inflammation, overstretching, or both of the posterial tibial tendon, which connects the tibialis posterior muscle to the bones in the foot. PTTD can cause pain in the inner ankle and development of a flat foot. Without treatment, correction of PTTD may require surgery. Standard interventions that may prevent the need for surgery include orthotic devices, bracing, and physical therapy, among other possibilities. Within physical therapy, foot exercises can be either active—as in the case of strengthening exercises—or passive—as in the case of stretching exercises. Evidence from clinical treatment of similar conditions suggests that active exercises are more effective than passive exercises in leading to recovery. This study will determine whether adding strengthening exercises to a normal intervention of bracing and stretching is more effective in improving a range of symptoms in stage II PTTD patients than using only bracing and stretching exercises.

Participants with Stage II PTTD will be recruited and placed in one of two groups for the duration of the 12-week study. The first group will undergo regular bracing and perform stretching exercises. The second group will undergo regular bracing and perform stretching and strengthening exercises.

Braces, worn during weight-bearing tasks throughout the study, will include ankle stirrup support and medial longitudinal arch support. Strengthening exercises, which will be preceded by a warm-up of the posterior tibialis muscle, will include bilateral heel raises, foot adduction and rear foot inversion with thera-tubing, and unilateral heel raises. Frequency of exercise and number of repetitions will increase over the course of the study until participants are performing 3 sets of 30 repetitions 2 times per day. Assessments, which will occur at study entry, after 6 weeks, and after 12 weeks, will include foot range of motion, length of the posterior tibial muscle, and self-assessments of function.