抄録
Measurements on arthrograms were compared between the presence and the absence of laxity of theglenohumeral joint for the purpose of assessing factors for glenohumeral instability.93 shoulders under 40 years old (average 20.7) were selected as subjects. Arthrography was conducted under imaging to obtain the anterior-posterior view in internal rotation by 60 degrees in the supine position as well as the axial view in abduction by 90 degrees in the sitting position, and these views were recorded. Then, the sizes of the anterior pouch and the inferior pouch and those of the anterior ballooning and posterior ballooning were measured respectively in the anterior-posterior view and in the axial view. The subjects were divided into two groups by the presence or absence of loosenig or slipping or anterior shift, and statistical tests to determine the significant differences were conducted. The patients, whose humeral head was moved anteriorly by not less than 20% when it was pushed from backwards in the same position as in the axial view, were determined as positive for anterior shift. There was no significant difference in the presence or absence of loosening. The patients who were determined to be positive in slipping had significantly larger anterior pouches (p<0.01). The patients who were determined to be positive for anterior shift had significantly larger anterior ballooning (p<0.05). Based on these results, we have reached the conclusion that expansion of the anterior pouch and that of anterior ballooning are respectively attributed to slipping and anterior shift.
