The purpose of this study is to see how much pain intensity is affected by high frequency spinal cord stimulation therapy in individuals with serious brachial plexus injury.

This single-site prospective observational cohort study will include all adults (> 18 years old) with brachial plexus avulsion injury who are candidates for high frequency (HF10) spinal cord stimulation (SCS). We plan to prospectively observe patients who undergo implantation of HF10 SCS for the indication of chronic neuropathic pain of the upper limb following brachial plexus avulsion injury.

Inclusion Criteria:

• Age > 18 years old
• Neuropathic pain of the upper limb ≥ 3 months following brachial plexus avulsion injury.
• Patients must be planned to undergo implantation of high-frequency spinal cord stimulation for the treatment of chronic neuropathic pain due to brachial plexus avulsion injury.

Exclusion Criteria:

• Pain that is non-neuropathic as defined by DN4 score <4.
• Pregnant at the time of consideration for implant or planning to become pregnant during the study duration.
• Active substance use disorder of any kind.
• Active tobacco use.
• Use of moderate or high dose opioid medication (oral morphine equivalents >100 mg daily).
• Active, untreated major psychiatric disorder that might interfere with subject's ability to participate.
• Involvement in active litigation related to injury.
• Patient has not undergone conservative medical management for at least 3 months (including physical and/or occupational therapy and at least one trial of neuropathic pain medication).

Adult patients with history of brachial plexus avulsion injury referred to the Pain Clinic for consideration of neuromodulation using high frequency neurostimulation will be considered.