Extaarticular manifestations of septic arthritis of the glenohumeral joint.

Five patients with septic arthritis involving the glenohumeral joint are described. Although initial plain films were normal in all six involved joints, abnormalities were frequent on subsequent examinations, including demineralization (five joints), joint space narrowing (three joints), superior subluxation of the humeral head (three joints), osseous erosion (two joints), and inferior subluxation of the humeral head (one joint). Arthrography was helpful in documenting intraarticular placement of the needle for aspiration, synovial abnormalities, and extraarticular extension of disease. Particularly noteworthy was the occurrence of rotator cuff tears in four of six shoulders, suggesting a possible relationship between joint infection and disruption of the rotator cuff.