Peripheral Nerve Stimulation of Brachial Plexus Nerve Roots and Supra-Scapular Nerve for Chronic Refractory Neuropathic Pain of the Upper Limb

Abstract

We report the outcome of a consecutive series of 26 patients suffering from chronic medically-refractory neuropathic pain of the upper limb (including 16 patients with complex regional pain syndrome), topographically limited, treated by brachial plexus (BP) nerve roots or supra-scapular nerve (SSN) peripheral nerve stimulation (PNS). The technique consisted in ultrasound-guided percutaneous implantation of a cylindrical lead (Pisces-Quad, Medtronic) close to the SSN or the cervical nerve roots within the BP, depending on the pain topography. All the patients underwent a positive trial stimulation before lead connection to a subcutaneous stimulator. Chronic bipolar stimulation mean parameters were: frequency 55.5 Hertz, voltage 1.17 Volts. The voltage was set below the threshold inducing muscle contractions or paresthesias. Two patients were lost immediately after surgery. At last follow-up (mean 27.5 months), the 20 patients still using the stimulation experienced a mean pain relief of 67.1%. Seventeen patients were improved ≥50%, including 12 improved ≥70%. In 11 patients with a follow-up >2 years, the mean pain relief was 68%. At last follow-up, respectively, six out of the nine (67%) patients treated by SSN stimulation and 10 out of 17 patients (59%) treated by BP stimulation were improved ≥50%. At last follow-up, 12 out of 20 patients still using the stimulation were very satisfied, six were satisfied, and two were poorly satisfied. Complications were: stimulation intolerance due to shock-like sensations (three cases), superficial infection (1), lead fractures (2), and migration (1). In this pilot study, SSN or BP roots PNS provided a relatively safe, durable and effective option to control upper limb neuropathic pain.