The Frequency of Superior Cluneal Nerve Entrapment Diagnosed With Ultrasound Guided Nerve Block

Cluneal nerves are a group of pure sensory nerves that provide direct cutaneous innervation to the buttocks. Superior cluneal nerve(SCN) originates from the T11-L5 nerve roots and has at least 3 branches from medial to lateral; these are the medial, intermediate, and lateral branches. Anatomy studies have shown that the medial branch passes 6-7 cm lateral to the midline on the posterior iliac crest. Nerve branches pass through the osteofibrous tunnel formed by the thoracolumbar fascia and the superior edge of the iliac crest, where they can be trapped. Controversial data exist regarding the osteofibrous tunnel. It may not be present in all cases, and in some cases more than one nerve has been shown to pass through the osteofibrous tunnel. As a result, there are discussions about superior cluneal nerve anatomy and there is not enough information. In patients with superior cluneal nerve entrapment syndrome, low back pain radiates to the upper part of the hip and may cause leg pain that mimics radiculopathy. The diagnosis is clinical. Diagnostic criteria for superior cluneal nerve (SCN) entrapment; Low back pain involving the iliac crest and buttocks, symptoms aggravated by lumbar movement or posture, trigger point over the posterior iliac crest corresponding to the nerve compression zone, patients report numbness and radiating pain in the SCN area (Tinel sign) when the trigger point is compressed, symptom relief by SCN block at the trigger point. Prevalence studies of superior cluneal nerve entrapment syndrome are very few. Maigne et al reported superior cluneal nerve entrapment in 1.6% of 1,800 patients with low back pain. Kuniya et al showed that 14% of 834 patients with low back pain met the criteria for superior cluneal nerve entrapment. Superior cluneal nerve entrapment is not as rare as it is thought to be among the causes of low back pain. In Turkey, there is no study showing the prevalence of the superior cluneal nerve or its importance in patients with low