Abnormal Paresthesias Associated With Radiofrequency Ablation of Lumbar Medial Branch Nerves: A Case Report.

Radiofrequency ablation (RFA) is an effective treatment that has occasionally been associated with transient paresthesias. This case report details an unusual presentation of paresthesias after lumbar medial branch RFA. A 48-year-old female patient reported pain, numbness, and swelling on the left buttock and posterolateral thigh. A physical exam revealed allodynia over the left posterolateral thigh without neurologic deficits two weeks after RFA of the left-sided lumbar medial branch nerves innervating the L4-L5 and L5-S1 facet joints. Shortly after the RFA of the contralateral targets, the patient complained of numbness of the right-sided lower back extending laterally from the right hip to the right knee. Imaging confirmed the appropriate placement of all needles in both procedures. Both instances of paresthesias resolved over time. This case report aims to demonstrate that RFA can be associated with unusual paresthesias and that these adverse effects do not warrant excessive workup.