Painful medial branch neuroma treated with minimally invasive medial branch neurectomy.

Study Design: Case report.

Objective: To report an unusual complication following lumbar facet radiofrequency denervation and describe a successful, minimally invasive treatment of a presumed medial branch neuroma.

Summary Of Background Data: Radiofrequency medial branch neurotomy is a common procedure for the treatment of mechanical back pain. Deafferentation injury and neuroma formation is well known and reported following chemical, surgical, and cryoablation neurolysis; however, it is thought to be rare with radiofrequency ablation. When this problem is encountered, treatment options appear to be limited. Further radiofrequency ablations may be ineffective and indeed may cause further injury.

Methods: A 17-year-old male who sustained a traumatic fracture of the right L3-4 facet joint presented with increasing back pain after multiple radiofrequency ablations of the medial branches of the L2 and L3 dorsal rami. The description of the back pain, initially nociceptive in nature, had become progressively neuropathic with clear focal areas of allodynia and hyperesthesia. Further medial branch radiofrequency denervation was found to be ineffective.

Results: Diagnostic block of the right medial branch of the L2 dorsal ramus provided the patient with total relief of pain. This was followed by a minimally invasive open surgical ablation of the L2 medial branch neuroma using three-dimensional, fluoroscopy-based image guidance. At 7 months of follow-up, the patient reported complete resolution of pain, discontinuation of all pain medications, and return to all previous physical activities.

Conclusion: Deafferentation injury is a rare but recognized complication of chemical, surgical, and thermal neuroablation. This case report presents a rare instance of presumed neuroma formation following multiple radiofrequency ablations for the treatment of facet-generated mechanical back pain. Open and minimally invasive medial branch neurectomy resulted in complete resolution of pain and return to baseline function.