Preliminary gait analysis results after posterior tibial tendon reconstruction: a prospective study.

The purpose of this study was to investigate the effect on gait in patients who underwent reconstruction for stage II posterior tibial tendon (PTT) dysfunction. Twelve patients with stage II PTT dysfunction underwent surgical reconstruction consisting of debridement of the posterior tibial tendon, flexor digitorum longus tendon transfer to the navicular tuberosity, medial displacement calcaneal osteotomy, and spring ligament reconstruction. Midfoot arthrodesis was performed in six patients and gastrocnemius recession in three. Gait analysis was performed 2 weeks prior to surgery and 1 year postoperatively. Preoperative and postoperative data were compared to determine differences in temporal-spatial parameters, lower limb kinematics, and ankle push-off power. Step length for the operated side increased from 52.6 +/- 9.6 cm before the surgery to 57.5 +/- 7.1 cm after the surgery (p =.048). Cadence improved from 100.2 +/- 10.7 steps/min to 109.1 +/- 8.5 steps/min (p =.05), thus increasing velocity from 87.6 +/- 22.6 cm/s to 103.4 +/- 15.9 cm/s (p =.042). Single support percentage was unchanged. Maximum sagittal ankle joint power at push-off increased from 0.79 +/- 0.35 W before surgery to 1.2 +/- 0.5 W after surgery (p =.042). There were statistically significant improvements in all radiographic parameters studied. This is the first prospective study to evaluate the in vivo effects on gait in patients undergoing this common surgical procedure. Analysis demonstrated statistically significant improvement in kinetic and kinematic parameters of gait function.