A Rare Case of Spinal Cord Injury Following Thoracic Radiofrequency Ablation.

Medial branch radiofrequency ablation (RFA) has become a common treatment for facet-related back pain. While this procedure is often performed in the lumbar and cervical spinal segments, it can also be applied to the thoracic spine. Complications of spinal RFA at any level are scarce in the literature and are often mild. The patient is a 37-year-old male with a family history of multiple sclerosis in his siblings who underwent thoracic RFA at the T2-T5 nerve root levels. Within one week of the procedure, the patient experienced paresthesias below the nipple line and progressive lower-extremity weakness. He was also found to exhibit urinary retention on presentation to our facility one month later. MRI showed focal cord short T1 inversion recovery (STIR) signal abnormality at the T3-T4 level, favored to represent myelomalacia. An extensive laboratory and imaging workup was otherwise unrevealing. The patient was treated with neuromodulators and a short course of inpatient rehabilitation. One year later, he used knee-ankle-foot orthoses for ambulating short distances and a manual wheelchair for longer distances, and he no longer required intermittent catheterization for bladder management. This case presents a rare and unusual timeline of symptom evolution, laboratory findings, and imaging results that do not unveil a clear pathophysiological mechanism, which led to the patient's spinal cord injury. The clinical level of injury based on the patient's symptoms and location of myelomalacia on MRI, however, strongly support a causative contribution by the thoracic RFA procedure.