DOES POSTOPERATIVE EPIDURAL ANALGESIA INCREASE THE RISK OF PERONEAL NERVE PALSY AFTER TOTAL KNEE ARTHROPLASTY

Peroneal nerve palsy is a rare complication of total knee arthroplasty (TKA). Previous studies have investigated surgical variables contribu ting to the development of peroneal nerve palsy after TKA, but have ig nored potential medical and anesthetic risk factors. The charts of all patients undergoing TKA over a 1-yr period were retrospectively studi ed to identify medical, surgical, and anesthetic risk factors contribu ting to the development of peroneal nerve palsy after TKA; 361 TKAs we re performed on 292 patients. There were eight peroneal nerve palsies in seven patients representing an overall incidence of 2.2%. A preoper ative valgus deformity greater than or equal to 10 degrees, total tour niquet time >120 min, the diagnosis of a preexisting neuropathy, and p ostoperative bleeding complications were identified as significant ris k factors. Postoperative epidural analgesia was used in 108 cases and was not a significant risk factor for the development of peroneal pals y. However, all cases of peroneal nerve palsy with motor deficits and partial neurologic recovery occurred in patients receiving postoperati ve epidural analgesia and were diagnosed after discontinuation of the epidural infusion. Since diagnosis of peroneal nerve palsy may be dela yed in patients with postoperative epidural analgesia, these patients must be monitored closely. A dilute local anesthetic or an opioid infu sion is recommended for patients at increased risk, such as those with preexisting neuropathies.