Axillar ultrasound of the glenohumeral joint.

A new ultrasonographic method for detection of intraarticular effusion in the glenohumeral joint was developed. The distance between the humerus and the joint capsule is measured at the axilla with the humerus in 90 degrees abduction. Effusion was detected by ultrasonography in 10 of 11 joints in which effusion was confirmed by intraarticular puncture. Intraarticular injection of physiological NaC1 solution could be seen as a change in the scan. The mean ultrasonographic distance between the head of humerus and the joint capsule was 2.4 mm (SD 0.5 mm) in 80 shoulder joints of 40 healthy adults. Thus, intrasynovial effusion can be suspected if the distance is 3.5 mm (mean + 2 SD) or more, or the difference between both sides is 1 mm or more.