棘下筋単独麻痺症例の臨床的検討

抄録

We report 6 patients with entrapment of the infraspinatus branch of the suprascapular nerve and discuss the diagnosis, pathology, treatment, and outcome over a mean follow-up period of 5 years. Each patient presented shoulder pain and weakness. EMG disclosed denervation and motor unit loss restricted to the infraspinatus muscle, with the supraspinatus muscle remaining normal. 2 patients were seen to have spaceoccupying lesions at the spinoglenoid notch by MRI, and ganglia were confirmed and removed surgically in 3 patients. Good results were seen in 3, but 1 required reoperation because of recurrence. We performed neurolysis and shaving of the spinoglenoid notch on a patient without ganglia. The other 2 patients without ganglia were treated conservatively. Our patients required 1 to 2 years to recover from paralysis of the infraspinatus muscle. Suprascapular neuropathy at the spinoglenoid notch should be included in the differential diagnosis of patients presenting shoulder pain and weakness.