[Shoulder movements during abduction and adduction of quadriplegic patients (author's transl)]

The relationship between glenohumeral and scapular movements during abduction and adduction of the limb in the scapular plane were studied in twenty normal subjects and nine quadriplegic patients by analysis of roentgenograms and enveloped electromyograms with electrogoniometer. In normal subjects the ratio of glenohumeral to scapulothoracic movement was 4.2 : 1 for the range 0-30 degrees and 1.7 : 1 for the range 30-150 degrees for abduction, and 1.9 : 1 for the range 150-30 degrees and 1.7 : 1 for the range 30-0 degrees for adduction. In comparing quadriplegic patients with normal subjects, outstanding medial shift of the scapula was observed in early phase of abduction, elevation, and upward rotation of the scapula which were limited through whole abduction. Distances of the shift of the scapula in quadriplegic patients were the same as those in normal subjects in the final phase of adduction. In enveloped electromyograms of normal subjects, each activity of the six sampled muscles, increased or decreased gradually during abduction and adduction in similar relationships. The upper fiber of the trapezius demonstrated the highest activity through abduction and adduction. During abduction and adduction the supraspinatus showed undulated wave patterns and had the plateau at 80-140 degrees. The activity of the supraspinatus was higher than that of the deltoideus statistically for the range 0-40 degrees for abduction. In each quadriplegic patient the patterns of muscle activities during abduction and adduction were characteristically peculiar and did not indicate any constant relationship findings in normal subjects, irrespective of the functional level.