Superior Cluneal Nerve Entrapment Neuropathy and Gluteus Medius Muscle Pain: Their Effect on Very Old Patients with Low Back Pain

Objective

In the very elderly, their general condition and poor compliance with drug regimens can render the treatment of low back pain (LBP) difficult. We report the effectiveness of a less-invasive treatment for intractable LBP from superior cluneal nerve entrapment neuropathy (SCN-EN) and gluteus medius muscle (GMeM) pain.

Patients and Methods

Between April 2013 and March 2015, we treated 17 consecutive elders with LBP, buttock pain, and leg pain. They were 4 men and 13 women ranging in age from 85 to 91 years (mean 86.6 years). We carefully ascertained that their symptoms were attributable to SCN-EN and GMeM pain. The median follow-up period was 21.5 ± 12.2 months (range 2–35 months).

Results

SCN-EN was diagnosed in 15 patients (28 sites) and GMeM pain in 14 (27 sites). In 5 patients, we obtained symptom control by local block (Numerical Rating Scale for LBP: declined from 7.8 to 0.8 [P < 0.05], Roland-Morris Disability Questionnaire score: declined from 16.5 to 5.2). The other 12 were operated under local anesthesia (SCN neurolysis, GMeM decompression). As 3 patients reported the persistence of leg pain postoperatively, they subsequently underwent peroneal nerve neurolysis and surgery for tarsal tunnel syndrome. These treatments resulted in significantly symptom abatement (Numerical Rating Scale: from 8.2 to 1.7, Roland-Morris Disability Questionnaire score: from 12.8 to 8.6; P < 0.05).

Conclusions

Even very old patients with intractable LBP, buttock pain, and leg pain due to SCN-EN or GMeM pain can be treated successfully by peripheral block and less-invasive surgery under local anesthesia.

Introduction

Low back pain (LBP), a global complaint,¹ is reported by many Japanese patients.² Among 1000 Japanese LBP sufferers, 39.8%, 182 men and 216 women, were between 70 and 79 years of age; 44.0%, 209 men and 231 women, were 80 years or older.³ The life expectancy in Japan is 80 years for men and 86 years for women⁴; in 2010, 3% of the total population was 85 years or older.⁵ Because the number of LBP complainants can be expected to increase, effective, minimally invasive treatment options are needed.

In some patients, LBP is not controlled adequately by conservative treatment, and drugs for pain control may be poorly tolerated.6, 7, 8, 9 In elderly patients, multiple factors may be involved, for instance, age-related spinal column deformation, dementia, noncompliance with drug regimens, coexisting medical diseases, and social background; they render the treatment of LBP in that population difficult.

Superior cluneal nerve entrapment neuropathy (SCN-EN), whose clinical features and etiology are understood poorly, is a causative factor in LBP, and its incidence tends to increase with aging.10, 11, 12, 13, 14, 15 It involves the iliac crest and buttocks and tends to be misdiagnosed as lumbar disorder. SCN-EN can be treated by less invasive procedures such as local block and surgery under local anesthesia.10, 11, 12, 14, 16, 17, 18, 19, 20, 21 Gluteus medius muscle (GMeM) pain can elicit buttock pain (BuP), and, like LBP, it affects the sufferer's quality of life. It can be treated by local block and decompression of the GMeM under local anesthesia.⁸ We treated very elderly patients with intractable pain by addressing their SCN-EN or GMeM and report herein the effect of our pain treatments.