Superior Cluneal Nerve Entrapment: A Retrospective Study of This Rare and Underdiagnosed Cause of Chronic Low Back and Leg Pain

Introduction:Superior cluneal nerve entrapment (SCNE) is a rare, peripherally mediated cause of chronic radicular low back and leg pain that is underdiagnosed, leading most patients to be evaluated as having nonspecific low back pain. Method:The files of 18 patients diagnosed with SCNE and treated with a superior cluneal nerve (SCN) block were examined. Records pertaining to interventional procedures performed on these patients, pain levels before the procedure (Numeric Rating Scale [NRS]-1) and Douleur Neuropathique 4 [DN4]-1), two weeks after the procedure (NRS-2 and DN4-2), and three months after the procedure (NRS-3 and DN4-3), as well as neuropathic pain symptoms, were used for this study. Results:Evaluation of NRS values showed a significant difference between NRS-1 and NRS-2 (p=0.000162) and between NRS-1 and NRS-3 (p=0.000186). The mean NRS score was 8.94 before interventional treatment and decreased to 2 three months afterward. Evaluation of DN4 values showed a significant difference between DN4-1 and DN4-2 (p=0.000399) and between DN4-1 and DN4-3 (p=0.001). The mean DN4 score was 2.77 before interventional treatment and decreased to 0.5 following the SCN block. Conclusion:Clinically, SCNE presents similarly to other causes of low back and leg pain.If not considered in the differential diagnosis, it may lead to unnecessary surgeries in patients with coexisting pathologies such as lumbar disc herniation.Pain may be reduced with a single block in some patients, while repeated blocks may be necessary in others. We believe that prospective, large-scale studies are needed to prevent unnecessary surgeries, increase awareness of the condition, and better define risk factors.