Outcome of surgical treatment of tarsal tunnel syndrome.

One hundred and eight ankles in 72 patients were evaluated from July 1986 to July 1997 with clinical findings and positive electrodiagnostic studies of tarsal tunnel syndrome. Clinical data included physical findings, subjective complaints, duration of symptoms, trauma history, steroid injections, nonsteroidal use and workman's compensation involvement. Associated medical conditions included diabetes, back pain and arthritis. Sixty-two patients underwent tarsal tunnel release, with 13 of them bilateral. There were 44 females and 18 males, 35 right feet and 40 left feet. The average age was 49 years. Preoperative symptom duration was 31 months. Average length of follow-up was 58 months. Average time for return to usual activity was nine months. All patients had at least a 12-month follow-up, and compared with both (Maryland Foot Score) MFS and AOFAS postoperative scores. Preoperative MFS scores obtained prior to 1994, were 61/100 (average), and postoperative MFS scores were 80/100 (average). Postoperative AOFAS scores were 80/100 (average). Patients with symptoms less than one year had postoperative MFS/AOFAS scores significantly higher than those with symptoms greater than one year. The most common surgical findings included arterial vascular leashes indenting the nerve and scarring about the nerve. Varicosities and space occupying lesions were present also. The outcome of surgery was not affected by the presence or absence of trauma. Patients with tarsal tunnel syndrome warrant surgery when significant symptoms do not respond to conservative management. Meticulous surgical technique must be followed. Improvement in foot scores is predictable even when a discrete space-occupying lesion is not present and when symptoms have been present for periods of greater than one year.