Relation between adhesive capsulitis and acromial morphology.

Abstract

The purpose of this study was to determine whether a relationship existed between primary adhesive capsulitis and acromial morphology. Case control series. Between January 1999 and June 2002, a total of 100 patients (104 shoulders) were diagnosed with adhesive capsulitis. A retrospective chart review was performed of all of these patients. A total of 67 patients (69 shoulders) met the inclusion criteria of primary adhesive capsulitis. The patients' range of motion and signs of impingement were documented. The supraspinatus outlet radiographs were assessed, and each patient's acromial morphology was graded as type I, II, or III. A case control group of 53 patients (58 shoulders) was assessed to determine the validity of our results. This group consisted of a series of new patients that were referred to the clinic during February 2003 for assessment of their shoulders. The average age of the patients in the adhesive capsulitis group was 52.5 +/- 7.6 years, with 34 women (50.7%) and 33 men (49.3%). The control group had an average age of 51.1 +/- 16.9 years in a series of 19 (35.8%) women and 34 (64.2%) men. The average range of motion was 98.0 degrees +/- 23.5 degrees of forward elevation, and 91.9 degrees +/- 24.3 degrees of abduction. The forward elevation was 165.5 degrees +/- 15.3 degrees and the abduction was 162.4 degrees +/- 18.4 degrees. The predominant acromial morphology in both groups in this study was a type II acromion (75.4% in the adhesive capsulitis group and 74.1% in the control group). The chi-square analysis within the specific groups showed statistically significant differences in the number of type II compared with type I acromions, and type II compared with type III acromions in both series. However, statistical analysis showed no significant difference between the various acromial types when comparing the adhesive capsulitis group with the control group. Our results show a significant number of patients with both adhesive capsulitis and, in the control group, type II acromions. We found no statistical difference between these 2 groups. Based on our results, the intrinsic trauma that occurs from subacromial space narrowing caused by the anterior acromial shape, cannot be implicated as the cause of primary adhesive capsulitis. Level III, case control study.