Acute Common Peroneal Nerve Decompression After Total Knee Arthroplasty

Common peroneal nerve palsy (CPNP) after total knee arthroplasty has a reported incidence of 0.3% to 4% and can lead to foot drop, equinovarus deformity, and marked disability if not resolved. Patients typically present in the early postoperative period with weakness or inability to dorsiflex the ankle and decreased sensation of the dorsum of the foot. The authors report their experience, technique, and outcomes of acute peroneal decompression within the first 90 days postoperatively for 5 patients with this unique complication. Preoperatively, all patients had valgus deformity with intact dorsiflexion and sensation of the foot. The diagnosis of CPNP was made on postoperative day 0 or 1 in all cases. After diagnosis, patients were offered acute peroneal decompression and returned to the operating room electively. The surgical technique for dissection, release, and decompression of the nerve is described. At an average follow-up of 12 weeks (range, 6-16 weeks), all patients showed return of motor and sensory function, as tested by ankle dorsiflexion and dorsal foot sensation, with average motor strength of 4.6 of 5.3. Acute decompression of acute CPNP after total knee arthroplasty is a prudent treatment option that provides good functional results and rapid recovery.