This case series demonstrates the safety and efficacy of a fully implantable axillary PNS system for chronic HSP. Participants experienced reduction in pain, reduction in pain interference, and improved pain-free external rotation ROM. There were no serious adverse events associated with the system or the procedure.

This case report describes the first participant treated with a fully-implantable, single-lead peripheral nerve stimulation (PNS) system for refractory hemiplegic shoulder pain (HSP). During the 6-wk trial-stage, a temporary lead was placed percutaneously near the terminal branches of the axillary nerve to the deltoid. The primary outcome measure was the Brief Pain Inventory-Short Form Question 3 (BPI-3), a 0–10 pain numeric rating scale. The participant experienced 75% pain reduction and proceeded to the implant-stage where he received a single-lead, implantable pulse generator. After 3-wks, the participant became pain-free. However, 7-wks after implantation, the system was turned off due to an unrelated acute medical illness. HSP reemerged with BPI-3 of 9. After 11-wks of recovery, PNS was reinitiated and the participant became pain-free through the 9-months follow-up. At 12-months, BPI-3 was a 1. This case report demonstrates the feasibility of a single-lead, fully-implantable PNS system for refractory HSP.