Surgical treatment of chronic phantom limb sensation and limb pain after lower limb amputation.

Abstract

Therapy for phantom sensation and phantom limb pain following amputation is still difficult, because pathophysiologic mechanisms have not been clarified. This report illustrates a simple and useful surgical intervention. The authors propose that changes at the peripheral nerve site can influence the central feeling of phantom sensation and pain. Fifteen patients (mean age, 56 years) with lower limb amputation were included in the study. In all patients, the sciatic nerve was split at a point approximately 3 cm proximal to the popliteal fossa, and the two parts were reconnected in a sling fashion using an epiperineurial technique under microscopic vision. The nerves were covered with a fibrin patch and anesthetics were applied by means of a local pain catheter. Frequency, duration, intensity, and quality of phantom pain were compared preoperatively and 1 week, 3 months, 6 months, and 1 year postoperatively. Fourteen of 15 patients defined the procedure as very helpful. Average, maximum, and minimum pain intensity were significantly reduced 1 week, 3 months, 6 months, and 1 year postoperatively (p < 0.001). Pain intensity scores decreased significantly over the long term after surgical intervention (median visual analogue scale score: preoperatively, 7; 1 year postoperatively, 4) (p < 0.001). The duration of pain attack shortened from approximately 120 minutes to 5 to 10 minutes. This study shows that accurate treatment of the peripheral nerve can help to successfully reduce phantom limb pain. The authors feel encouraged to perform future investigations to test their operative method in a prospective, randomized, matched control study including electrophysiologic tests for more objective pain assessment.