[Non-Specific Back Pain due to Superior Cluneal Nerve Entrapment Neuropathy Treated with Neurolysis: A Case Report].

A 43-year-old man with a 10-year history of low back pain (LBP) had been conservatively treated elsewhere with medications for non-specific back pain. He presented to our institute with LBP and difficulty in standing up, sitting down, and sitting for prolonged periods. His Numerical Rating Scale score, due to LBP, was 8 out of 10. He had numbness on the lateral aspect of his left thigh. A lumbar radiography and magnetic resonance imaging studies revealed mild degenerative changes and mild canal stenosis in the lumbar spine. Palpation over the left posterior superior iliac crest, 8 cm from the midline over the iliac crest, revealed severe tenderness. A superior cluneal nerve(SCN)block performed at the trigger point in both the buttocks resulted in complete pain abatement and disappearance of the radiating pain. Therefore, we diagnosed SCN entrapment neuropathy(SCNE). However, the pain reappeared a few days later and subsequent treatments failed to relieve it; therefore, we decided to perform surgery. The SCN penetrates the thoracolumbar fascia through an orifice just before crossing over the iliac crest. We opened the orifice with microscissors in a distal to rostral direction along the SCN and released the entrapped nerve. After surgery, the symptoms were relieved and the patient experienced no recurrence in the last 4 years after the treatment. SCNE should be considered as a causative factor of LBP, and its treatment using minimally invasive surgery yields excellent clinical outcome.