The tarsal tunnel syndrome: evaluation of surgical results using multivariate analysis.

Thirty-four patients with the tarsal tunnel syndrome were treated by decompression of the posterior tibial nerve. The condition was bilateral in 3 cases. There were 9 men and 25 women with an average age at operation of 41 years. The average follow up was for 3.8 years. Multivariate analysis showed that the outcome is influenced, in order of importance, by fibrosis around the nerve, the preoperative severity of the condition, a history of sprained ankle, worker's compensation, a long history, and heavy work. The results were favourable when there was a short history, the presence of a ganglion, no sprains, and light work. Measurement of the terminal latency of the medial plantar nerve was valuable in assessing recovery. The precise cause of the syndrome and its effect on treatment should be considered before operation.