一次性変形性肩関節症における肩甲骨関節窩の形態調査

抄録

Background: There was no morphologic study, which investigated in the primary glenohumeral osteoarthritis (GHOA) in Japanese. The purpose of this study is to investigate whether there are any characteristic changes of the primary GHOA with CT scans.
Methods: CT scans were obtained of 57 shoulders with primary osteoarthritis of the glenohumeral joint. The measurement was performed at the middle level of the glenoid. Glenoid morphology was assessed qualitatively by measurement of the glenoid retroversion using the technique reported by Friedman et al (1). Morphologic changes of the glenoid were evaluated by Walch's classification (2) as follows; Type A was characterized by a well-centered humeral head and a balanced distribution of strengths against the surface of the glenoid. The erosion may be minor-type A1 or major-type A2. In Type B, the posterior subluxation of the humeral head was responsible for the asymmetric load against the glenoid, particularly the exaggerated posterior wear pattern: B1 showed narrowing of the posterior joint space, subchondral sclerosis, and osteophytes, and type B2 demonstrated a posterior cupula that gave an unusual biconcave aspect of the glenoid. Type C was defined by a glenoid retroversion of more than 25 degree.
Results: Mean Glenoid retroversion was 5.7°. Morphology was classified as follows; 61% classified in type A, of them A1 in 49% and A2 in 12%. 37% in type B, of them B1 in 23% and B2 in 14%. 2% in type C.
Conclusion: There are some difference between Japanese and Westerns in morphologic change of the primary glenohumeral osteoarthritis.