Is the Position and Union of the Tuberosities Assessable by Means of the Simple Radiograph After Reverse Shoulder Arthroplasty for Complex Proximal Humerus Fractures?

Background: The assessment of tuberosity position and union in reverse shoulder arthroplasty (RSA) for complex proximal humerus fractures (PHF) has been carried out by means of routine simple radiographs. To evaluate the interobserver agreement and intraobserver reproducibility of the simple radiograph in comparison to the CT scan.

Methods: The position and consolidation of the tuberosities in 2 radiographic projections and in a CT scan of 32 consecutive patients operated on a RSA for PHF was assessed by 5 observers. Interobserver agreement and intraobserver reproducibility in both imaging tests were also assessed.

Results: The interobserver agreement for the greater tuberosity position was 0.52 in the simple radiograph and 0.45 in the CT scan. For the greater tuberosity union, agreement was moderate in the simple radiograph (0.52), but fair in the CT scan (0.35). For the lesser tuberosity position and union, the agreement was fair in the radiograph and poor in the CT scan.

Conclusion: Only moderate agreement was observed in the assessment of the position and union of the tuberosities in the RSA for PHF in the simple radiograph and no improvement in it was seen for the 2D CT scan.