Results of posteroinferior capsular shift in patients with posterior shoulder instability

Purpose: The purpose of this study was the evaluation of our results after posteroinferior capsular shift in patients with a posterior shoulder instability. Materials and methods: In a prospective study we evaluated 12 patients (14 shoulder joints) with recurrent posterior shoulder dislocations who were stabilized by a postero-inferior capsular shift procedure. For the clinical documentation the Rowe-Score, the ASES-Score and the SF-36 were used. Furthermore the patients were submitted to standardized EMG-, isokinetic and proprioceptive tests. Results: After an average follow-up of 22.2 months there were two recurrences which occurred during the first postoperative year. The Rowe-Score improved from 46.25 to 76.34 points. The ASES-Score showed an average of 42.43 points preoperatively and at the time of follow-up an average of 78.86 points. Most parameters of the ASES-Score as well as the score in total had a constant positive tendency. Only the subjective rating of stability showed a slight decrease after the first six months due to the two redislocations. But even the stable shoulder joints demonstrated limitations when throwing a ball. The SF-36 showed a definite gain in the overall quality of living as well. The EMG-tests at follow-up showed a deficit for the patients compared with a control group; even more for the female than for the male patients. Similar tendencies were found with the isokinetic strength. The proprioception did not show any differences between the patients and the control group. Conclusion: With adequate patient selection and after failure of all possible conservative treatments the posteroinferior capsular shift is a therapeutical option in recurrent posterior shoulder instability.