Injury of the suprascapular nerve at the spinoglenoid notch. The natural history of infraspinatus atrophy in volleyball players.

From 1985 to 1996, we observed 38 cases of isolated atrophy of the infraspinatus muscle in athletes; all were involved in volleyball at a competitive level. There were 20 men and 18 women with a mean age of 26 years (range, 15 to 27). At the time of the first examination, 35 of these athletes had no pain and were treated with exercises to strengthen the external rotators. The remaining three patients underwent surgery because of pain at the posterior aspect of the shoulder. Sixteen of the 35 players treated nonoperatively were reviewed at a mean follow-up of 5.5 years (range, 3 to 10). Thirteen were still involved in volleyball and three had retired symptom-free at the end of their careers. On physical examination, atrophy of the infraspinatus muscle was unchanged in all cases. The patients treated surgically were reviewed at a mean follow-up of 2 years. All of them were able to play volleyball at their preinjury levels, but one had pain at the anterior aspect of the shoulder after strenuous activity. Physical examination showed a notable reduction of the atrophy in one patient. Entrapment of the suprascapular nerve at the spinoglenoid notch is a usually painless syndrome that is frequently observed in volleyball players. Surgical treatment is indicated in the rare cases of painful neuropathies after careful patient selection.