Prospective study of superior cluneal nerve disorder as a potential cause of low back pain and leg symptoms

Abstract

BackgroundEntrapment of the superior cluneal nerve (SCN) in an osteofibrous tunnel has been reported as a cause of low back pain (LBP). However, there are few reports on the prevalence of SCN disorder and there are several reports only on favorable outcomes of treatment of SCN disorder on LBP. The purposes of this prospective study were to investigate the prevalence of SCN disorder and to characterize clinical manifestations of this clinical entity.MethodsA total of 834 patients suffering from LBP and/or leg symptoms were enrolled in this study. Diagnostic criteria for suspected SCN disorder were that the maximally tender point was on the posterior iliac crest 70 mm from the midline and that palpation of the tender point reproduced the chief complaint. When patients met both criteria, a nerve block injection was performed. At the initial evaluation, LBP and leg symptoms were assessed by visual analog scale (VAS) score. At 15 min and 1 week after the injection, VAS pain levels were recorded. If insufficient pain decrease or recurrence of pain was observed, injections were repeated weekly up to three times. Surgery was done under microscopy. Operative findings of the SCN and outcomes were recorded.ResultsOf the 834 patients, 113 (14%) met the criteria and were given nerve block injections. Of these, 54 (49%) had leg symptoms. Before injection, the mean VAS score was 68.6 ± 19.2 mm. At 1 week after injection, the mean VAS score significantly decreased to 45.2 ± 28.8 mm (p < 0.05). Ninety-six of the 113 patients (85%) experienced more than a 20 mm decrease of the VAS score following three injections and 77 patients (68%) experienced more than a 50% decrease in the VAS score. Surgery was performed in 19 patients who had intractable symptoms. Complete and almost complete relief of leg symptoms were obtained in five of these surgical patients.ConclusionsSCN disorder is not a rare clinical entity and should be considered as a cause of chronic LBP or leg pain. Approximately 50% of SCN disorder patients had leg symptoms.Electronic supplementary materialThe online version of this article (doi:10.1186/s13018-014-0139-7) contains supplementary material, which is available to authorized users.

Diagnosis and Characters of Non-Specific Low Back Pain in Japan: The Yamaguchi Low Back Pain Study

“…Previous work reported that entrapment of the SCN should be considered as a cause of chronic LBP or leg pain [25]. Some of the patients classified as “others” in this study may therefore have had SCN disorder.…”

Anatomical study of middle cluneal nerve entrapment

“…Trescot10 and Kuniya et al11 stated that cluneal neuralgia is not a rare clinical entity and may be underdiagnosed and should be considered as a differential diagnosis for chronic LBP or leg pain.…”

Low back pain due to superior cluneal nerve entrapment: A clinicopathologic study

“…The etiology of low back pain (LBP) is heterogeneous and unknown in some patients with chronic pain . Superior cluneal nerve entrapment (SCN‐E) has been proposed as a causative factor; its reported incidence ranges from 1.6%–14% . The SCN derives from the cutaneous branches of the dorsal rami at T11‐L4 and innervates the skin of the upper part of the buttocks .…”

“…1 Superior cluneal nerve entrapment (SCN-E) has been proposed as a causative factor [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] ; its reported incidence ranges from 1.6%-14%. 10,11 The SCN derives from the cutaneous branches of the dorsal rami at T11-L4 and innervates the skin of the upper part of the buttocks. [18][19][20] The nerves pass over the iliac crest through a tunnel formed by the thoracolumbar fascia and the superior rim of the iliac crest; the SCN may be compressed in this area.…”

“…[18][19][20] The nerves pass over the iliac crest through a tunnel formed by the thoracolumbar fascia and the superior rim of the iliac crest; the SCN may be compressed in this area. Patients whose chronic LBP was successfully relieved by local decompression via SCN neurectomy or neurolysis at the orifice of the thoracolumbar fascia have been reported, 4,10,13,14 suggesting that SCN-E in an orifice of the thoracolumbar fascia may be implicated in LBP. 20 However, the pathologic background of SCN neuropathy is not well understood.…”