Piriformis syndrome: a simple technique for US-guided infiltration of the perisciatic nerve. Preliminary results.

The piriformis syndrome is an uncommon cause of sciatica, buttock or thigh pain. Because of the deep location of the muscle and sciatic nerve, infiltration has traditionally been guided by electromyography, fluoroscopy, computed tomography or magnetic resonance imaging. The aim of the present study is to describe a simple technique for ultrasound (US)-guided perisciatic infiltration of corticosteroids and anaesthetic using the inferior gluteal artery as a landmark. This technique was used satisfactorily in ten patients. Although the series in the study is limited, the procedure for US-guided infiltration of the perisciatic nerve is a quick, simple, economical and effective technique and can be considered an alternative in the percutaneous treatment of the piriformis syndrome.