Background and Objectives Pain due to superior cluneal nerve entrapment is an infrequent cause of unilateral low back pain. Here we present a case of acute unilateral low back pain treated by superior cluneal nerve (SCN) block.

Case Report A 55-year-old woman presented to the outpatient clinic suffering from unilateral low back pain localized to right iliac crest and radiating to the right buttock. Her history was taken, physical examination was performed, and a thorough radiologic evaluation was performed to minimize radiculopathy and facet syndromes as causative. After transient pain relief with a diagnostic trigger point injection, entrapment of SCN was diagnosed and therapeutic nerve block with local anesthetic and steroid combination was performed.

Conclusion SCN is prone to entrapment where it passes through the fascia near the posterior iliac crest. Unilateral low back pain and deep tenderness radiating to the ipsilateral buttock are the clinical findings accompanying SCN entrapment. The case presented emphasizes the relief of possible SCN after limiting other etiologic causes of low back pain.