Clinical results after tarsal tunnel decompression.

We reviewed the clinical results for thirty patients (thirty-two feet) who had had exploration and decompression of the posterior tibial nerve for the treatment of tarsal tunnel syndrome between 1982 and 1990. The average duration of follow-up was thirty-one months (range, twenty-four to 118 months). Most of the patients were female, and the average age was forty-seven years (range, thirteen to seventy-two years). Over-all, only fourteen (44 percent) of the thirty-two feet benefited markedly from the operative procedure (a good or excellent result). Of the five patients (five feet) who were completely satisfied, three had another lesion (a ganglion cyst, an accessory navicular bone, or a medial talocalcaneal coalition) in or near the tarsal tunnel that had been treated at the same time. Eleven patients (twelve feet 38 percent) were clearly dissatisfied with the result and had no long-term relief of the pain (a poor result). The pain was decreased in six feet (19 percent), but the patients still had some pain and disability (a fair result). There were four complications (13 percent): three wound infections and one delay in wound-healing. Twenty-two feet had had preoperative electrodiagnostic studies; the results of eighteen studies were considered abnormal and supportive of a diagnosis of tarsal tunnel syndrome. However, there was no correlation between the clinical outcome at the latest follow-up visit and the results of these studies. Over-all, the patients in the current series had less improvement than those who have been reported on previously.2