Correction of Drop-Foot in Common Peroneal Nerve Palsy

Abstract

Drop-foot is a consequence of a common peroneal nerve palsy, which is a disabling condition characterized by a steppage gait. For the cases in which the primary nerve repair does not produce muscle reinnervation or the nerve reconstruction is not indicated, a dynamic tendon transposition may be a plausible surgical option for the restoration of functional dorsiflexion. In an effort to find a solution to the major disadvantage of the numerous techniques, which were developed from the original procedure presented by Codivilla and Putti, we use the anterior tibialis tendon (ATT) rerouting technique. We reroute the ATT on the dorsum of the tarsus by drilling a transosseous tunnel from the first to the third cuneiform. With this approach, we create a new tendon origin at the level of the third cuneiform. The ATT is then passed under the extensor retinaculum, reaching the distal third of the leg. The posterior tibialis tendon (PTT) and the flexor digitorum longus (FDL) tendon are transferred through the anterior aspect of the interosseous membrane. A tendon-to-tendon suture is performed between the ATT and PTT using the Pulvertaft technique, and similarly, the FDL tendon is sutured end-to-side to the extensor digitorum longus and extensor hallucis longus tendons. Originating a new tendon at the tarsus and the positioning of the recipient ATT in closer proximity to the donor PTT are novel aspects of this technique. These modifications produce a sufficient tendon length, which would permit an easy tendon-to-tendon suture at the distal third of the leg. This, in turn, eliminates the PTT length-related problems associated with other techniques. The transfer of the FDL tendon, which is associated with a straight line of pull, improves the power of foot dorsiflexion not only avoiding the drop of toes but also allowing the voluntary dorsiflexion of digits.