Posterior tibial tendon transfer: results of fixation to the dorsiflexors proximal to the ankle joint

BACKGROUND: Most techniques for posterior tibial tendon transfer attach the posterior tibial tendon somewhere at the dorsum of the foot. Inadequate tendon length and difficulties in securing the tendon to bone or tendon can complicate these procedures. Performing the tenodesis proximal to the ankle joint can prevent these problems. The present study is the first to describe the results of posterior tibial tendon transfer through the interosseous membrane attaching only the posterior tibial tendon to the extensor tendons proximal to the ankle joint. METHODS: We examined 13 feet in 12 patients with a foot-drop, equinovarus deformity, or both. The median (range) followup was 3.7 years (9 to 81 months) and the median age at surgery as 30 (13 to 59) years. Evaluation included recording patient satisfaction, use of ankle-foot orthoses (AFO), video-assisted gait analysis, physical examination, the Stanmore system, modified Ninkovi? method, and complications. RESULTS: At followup, patient satisfaction was excellent to good in nine feet. Ten of the 11 feet that needed an AFO preoperatively did not need one after surgery. Gait analysis demonstrated a good to fair gait in 10 patients. Median dorsiflexion was 0 (-25 to 12) degrees, with dorsiflexion to a neutral position or beyond in nine feet. The Stanmore system and modified Ninkovi? method showed excellent to good results in 10 feet. Three complications were recorded including one failed tendon transfer. CONCLUSIONS: Attachment of a split posterior tibial tendon to the extensor tendons proximal to the ankle joint provides results equivalent to other procedures and can be considered a viable operative alternative because it is less difficult and more straightforward than other techniques.