SUPRASCAPULAR NERVE ENTRAPMENT CAUSED BY SUPRAGLENOID CYST COMPRESSION

Twenty-two cases of suprascapular nerve entrapment caused by supraglen oid cyst compression were reviewed. Pain and weakness were the present ing symptoms in 14 shoulders and pain alone in 8. Twenty of the cysts were diagnosed by magnetic resonance imaging, and two were confirmed a t surgical exploration. Electromyography of 20 shoulders was positive For neurologic involvement for both the infraspinatus and supraspinatu s in 4 cases, for the infraspinatus only in 12, and negative in 4. Six teen shoulders were treated by open excision, arthroscopy, or both. Su perior labral lesions were diagnosed in 11 of 12 patients who underwen t arthroscopy. At follow-up 10 of the patients who underwent surgery h ad complete resolution of symptoms, 5 had occasional pain or weakness, and 1 recurrence required a second surgery. OF six patients treated w ithout surgery, two improved and Four had no change. Supraglenoid gang lion cysts are common and can easily be diagnosed by magnetic resonanc e imaging. For patients with symptoms arthroscopy with repair of the s uperior labral lesion and either arthroscopic debridement or direct op en decompression and excision of the cyst is recommended.