Painful shoulder in hemiplegic patients: a study of the suprascapular nerve.

The etiology of painful shoulder in hemiplegic patients has not been fully explained. Since it has been shown that a suprascapular nerve lesion can be associated with "frozen shoulder," we have investigated the possibility that a similar lesion may exist in the painful contracted shoulder of hemiplegic patients. Thirty hemiplegic men with shoulder pain were examined and latencies determined for the suprascapular nerve from the supraclavicular fossa to the supra- and infraspinatus muscles on both sides. Routine EMG was also done for the same muscles. Patients' ages ranged from 45 to 85 (means 67 years) and the duration of hemiplegia from 1 month to 13 years (means 30.9 months). Mean latencies of the noninvolved side were 3.2 +/- 0.5 (SD) and 4.2 +/- 0.7 ms to the supraspinatus and the infraspinatus muscles, respectively. Three patients had latencies greater by two SD on the hemiplegic side than on the noninvolved side. Suprascapular nerve block did not relieve the shoulder pain completely in these patients. Excluding these three, mean latencies on the hemiplegic side were 3.1 +/- 0.4 ms to the supraspinatus muscle and 4.1 +/- 0.6 ms to the infraspinatus muscle. It is concluded that a lesion of the suprascapular nerve is not responsible for the painful contracted shoulder of the hemiplegic patient although such a lesion may exist incidentally.