Entrapment Neuropathy of the Medial Superior Cluneal Nerve

Abstract
In this study, the authors analyzed the results of the release of the medial superior cluneal nerve in a prospective series of 19 patients with suspected entrapment. To ascertain, in selected patients with low back pain, medial superior cluneal nerve entrapment compromise at the posterior iliac crest crossing site, and to evaluate the results of nerve release. A cadaveric study had shown that the medial superior cluneal nerve may be compressed at its transit site through an osseofibrous orifice at the posterior iliac crest. Nineteen patients suffering from unilateral low back pain projecting in the territory of the medial superior cluneal nerve, with a trigger point at the posterior iliac crest and with a positive block test at this level, underwent surgery. Results were excellent in 13 cases (7 of which had suffered from severe compression), and unsatisfactory in 6 cases (including 4 cases in whom no compression could be demonstrated). Entrapment neuropathy of the medial superior cluneal nerve is a rare and easily treatable cause of unilateral low back pain.