肩甲上神経の神経伝導測定による
障害部位診断

伊　藤　順　子*
　　　　　　　　　　　　　　　　　　　　　　
Nerve Conduction Studies of Suprascapular Nerve for Site-of-Lesion Diagnosis

Junko ITO, MD, PhD*

Shoulder pain is a common symptom, resulting not only from bone and shoulder joint diseases, but also from neurogenic lesions. Entrapment neuropathy of the suprascapular nerve also causes shoulder symptoms. Conduction of the suprascapular nerve was studied in 12 healthy control subjects and 25 patients suffering from shoulder pain and/or dysfunction. Surface stimulation was performed at Erb's point, and compound muscle action potentials(M waves) were recorded from the supraspinatus and the infraspinatus muscles with concentric needle electrodes. To determine the optimal site for recording M waves from the infraspinatus muscle, simultaneous multi-channel recordings of M waves using pairs of surface electrodes were obtained from different sites over the infraspinatus muscle.
In two patients, latency of the M waves to the infraspinatus muscle was prolonged, whereas that to the supraspinatus muscle was normal. These findings indicate entrapment neuropathy at the spinoglenoid notch. In three patients, the latency to the infraspinatus and supraspinatus muscles was prolonged. These findings are compatible with entrapment neuropathy at the suprascapular notch. The latency to the supraspinatus and infraspinatus muscles was prolonged in patients with brachial plexus injury and in those with suprascapular nerve injury. In patients with myopathy, those with neuralgic amyotrophy and those with cervical radiculopathy, the latency was normal.
Thus, conduction studies of the suprascapular nerve using multiple-channel recordings are useful, especially for the diagnosis of entrapment neuropathy of the suprascapular nerve.
[Rinsho Byori 50 : 600〜604, 2002]

*Department of Laboratory Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507

【Key Words】nerve conduction studies(神経伝導測定検査)，suprascapular nerve(肩甲上神経)，entrap-ment neuropathy(絞扼性末梢神経障害)，multiple-channel recording(多チャンネル記録)

受付2001年9月28日・受理2002年2月8日
*京都大学大学院医学研究科臨床生体統御医学・臨床病態検査学講座(〒606-8507 京都市左京区聖護院川原町54)

E-mail :jito@kuhp.kyoto-u.ac.jp