Clinical results of transferring a motor branch of the tibial nerve to the deep peroneal nerve for treatment of foot drop.

BACKGROUND: Foot drop is a very debilitating condition affecting patients' daily activities, and its treatment has been a challenge for neurosurgeons. Grafting the peroneal or sciatic nerve usually results in poor outcomes. Our previous anatomic study demonstrated the feasibility of transferring a motor branch of the tibial nerve to the deep peroneal nerve at the level of the popliteal fossa.

OBJECTIVE: To demonstrate the outcomes obtained after the transfer of a branch of the tibial nerve to the peroneal nerve for recovery of foot drop.

METHODS: A retrospective review of 13 patients with foot drop caused by injuries to a lumbar root or the sciatic or peroneal nerve, who underwent a transfer of the nerve of the soleus muscle to the deep peroneal nerve. The results were evaluated using the British Medical Research Council grading system.

RESULTS: Three patients were lost to follow-up. Of the remaining 10 patients, the outcomes were considered good (Medical Research Council grade M3 or M4) in 2 patients (20%) concerning ankle dorsiflexion and in 2 patients concerning toe extension (20%). One patient reported a reduced calf circumference.

CONCLUSION: The transfer of the nerve of the soleus muscle to the deep peroneal nerve demonstrated poor results in most of the patients, although favorable outcomes were observed in a few subjects. Due to the inconsistency of the results, we do not favor the routine use of this technique for the treatment of foot drop.