Computed arthrotomography of the glenohumeral joint to evaluate anterior instability: correlation with arthroscopic...

A retrospective review of 30 patients on whom a double-contrast computed arthrotomogram of the shoulder was performed was evaluated to correlate radiographic findings with subsequent arthroscopic and surgical findings. Analysis of the data demonstrated a wide variation in abnormal computed tomography (CT) labral configurations, and experience was necessary to interpret the studies adequately. The lesions ranged from complete detachment to complete absence. The study was reliable in identifying large labral lesions suitable for arthroscopic stapling with large detachments anteriorly and anterior inferiorly. Isolated low anterior labral detachments associated clinically with instability under anesthesia were missed. The amount of tissue available for arthroscopic stapling correlated well with CT findings, making it a useful screening test to help select candidates for arthroscopic stapling. One false-positive study and two false-negative studies were noted, for an error rate of 10%. We recommend continued use of the CT arthrotomogram of the shoulder as a screening test for shoulder derangement and as a predictive adjunct for surgical planning. Modifications in our technique include tangential low anterior imaging to detect low anterior short labral detachments.