Nerve Protection Evaluation: Revision Cubital Tunnel Syndrome Decompression

Inclusion Criteria: 1. Be ≥ 18 years of age; 2. Have symptoms of ulnar nerve neuropathy near the elbow present at 180 days or greater following a primary cubital tunnel decompression procedure. 3. Be eligible for surgical intervention; 4. Have a preoperative diagnostic such as a nerve conduction study, electromyography, or ultrasound evaluation documenting ulnar neuropathy at the elbow; 5. Have a baseline pain visual analogue scale (VAS) score due to ulnar nerve neuropathy of no less than 40/100 mm for the affected elbow; 6. Have at least one of the following: * Paresthesia or numbness in the ulnar nerve distribution; * Weakness or wasting of the small muscles of the hand (full hand muscle wasting is excluded); * A positive elbow flexion provocation test. 7. Undergo a first revision cubital tunnel decompression surgery with placement of Axoguard HA+ Nerve Protector circumferentially around the section of ulnar nerve affected by neuropathy; 8. Be willing and able to comply with all aspects of the treatment and evaluation schedule over 18 months; and 9. Sign and date an Institutional Review Board (IRB)/Independent Ethics Committee (IEC)-approved written informed consent prior to initiation of any study procedures. Exclusion Criteria: 1. Have had a previous revision cubital tunnel decompression procedure; 2. Have documented evidence of concomitant neuropathic conditions affecting the subject arm or any proximal condition affecting the subject arm including, but not limited to: * Previously treated carpal tunnel syndrome with unresolved symptoms or current carpal tunnel syndrome that will not be treated concurrently with the revision cubital tunnel; * Cervical or brachial plexus abnormalities or injuries; * Cervical spine or shoulder disease; * Thoracic outlet syndrome; * Complex regional pain syndrome; * Polyneuropathy, systemic neuropathy or Lyme disease related neuropathy; * Previous or current surgery of the ulnar nerve at the wrist (Guyon's canal release) * Ulnar nerve compression at the wrist/Guyon's canal; 3. Have current trauma or past trauma with ongoing pathology that interferes with evaluation or treatment of the ulnar nerve to either side shoulder or upper extremity; 4. Have previous radiofrequency ablation, presence of nerve stimulator or received nerve implant(s) in the subject arm or be receiving an implant(s) other than Axoguard HA+ Nerve Protector during the study surgical procedure, that will impact the ulnar nerve or planned study evaluations; 5. Have a condition(s) that could confound assessments or health-related quality of life including, but not limited to: * Rheumatoid arthritis * Fibromyalgia * Connective tissue disorder * Wrist tenosynovitis 6. Be a smoker or tobacco user; 7. Currently have or have a history of alcohol or drug abuse; 8. Have uncontrolled Diabetes Mellitus at the discretion of the treating surgeon or have diabetic neuropathy in the upper extremities; 9. Have documented poorly controlled hyperthyroidism or hypothyroidism; 10. Have a known sensitivity to porcine derived materials or those containing hyaluronate or alginate or their components; 11. Be currently taking or likely to need medication(s) that may cause or contribute to peripheral neuropathy or peripheral nerve dysfunction at the discretion of the treating surgeon; 12. Be taking prescribed medication(s) including, but not limited to, narcotics 2 or more times per week for the treatment of chronic pain or chronic nerve related symptoms NOT associated with the subject ulnar nerve neuropathy; or 13. Be deemed unsuitable for inclusion in the study at the discretion of the investigator.