DYNAMIC ARTHRO-CT IN THE DIAGNOSIS OF RECURRENT SUBLUXATION OF THE SHOULDER

''Dynamic'' double contrast arthro-CT in inernal and external rotation was performed on 42 patients with recurrent subluxation of the shoulder. The differential distribution of contrast and air caused by the rotation resulted in optimal demonstration of the capsulo-labral components responsible for joint stability. In 22 patients there appeared to be an indication for arthroscopy; this confirmed the previous findings. In all cases the anterior part of the capsule and the middle and lower labrum were seen best during internal rotation. In this way all the 15 anterior capsule lesions could be seen, as well as 16 out of 17 Bankart lesions; it also showed one lesion of the middle labrum which had been masked by a haemarthrosis during external rotation. The study also defined lesions of the upper labrum caused by a different pathological mechanism which was present in 7 patients (6 Andrews and 1 S.L.A.P. lesion). These and 2 posterior labrum tears could be diagnosed during external rotation. Sensitivity for lesions of the anterior labrum was 95 %.