Surgical decompression improves symptoms of late peroneal nerve dysfunction after TKA.

Acute peroneal nerve palsy is a well-known complication of total knee arthroplasty (TKA) that causes a neurological deficit typically seen within hours or days postoperatively. Peroneal nerve dysfunction presents more subtlely than peroneal nerve palsy, with decreased knee range of motion, lateral knee pain, or both following TKA. The diagnosis of peroneal nerve dysfunction may not be suspected for weeks, months, or even years after TKA. Electromyography and nerve conduction studies can support the diagnosis. Historically, peroneal nerve palsy following TKA has been treated nonoperatively but has had an unsatisfactory rate of complete recovery. Recently, a few reports have demonstrated that patients with either peroneal nerve palsy or dysfunction after TKA have had excellent results with surgical decompression of the peroneal nerve.The authors describe a 63-year-old woman who reported transient episodes of lateral knee and leg pain for years after undergoing TKA. She eventually underwent electromyography and nerve conduction studies that indicated a diagnosis of peroneal nerve dysfunction. Approximately 10 years after the TKA, she underwent surgical decompression of the peroneal nerve and has done well since, with significant pain relief and an increased activity level.This case supports the recent literature describing peroneal nerve dysfunction as an uncommon but surgically treatable cause of lateral knee pain following TKA. Increased awareness of the condition and its facile treatment via surgical decompression may result in improved outcomes years after TKA.