The question
In a reverse shoulder arthroplasty, the humeral component is set at a particular rotation, described as retroversion. One common way of judging that rotation during surgery is to reference the forearm using a guide. This study asked whether that method actually achieves the rotation the surgeon intends.
What was found
The findings suggest that extramedullary forearm referencing may not yield precise results, with the discrepancy more pronounced in women. Component alignment has a bearing on how a replacement functions and loads over time, which is why a method that introduces variability is worth identifying.
The paper argues for further development of more advanced referencing systems. Individual results vary, and the full figures are in the published paper.
First author
The first author is Dr Mohammad Nedal Jomaa, MD, a clinical fellow at the Brisbane Shoulder Fellowship, who has since returned to Lebanon as the first subspecialty shoulder surgeon there.
Authors and affiliations
Mohammad Nedal Jomaa, Ashish Gupta, Marco Branni, Helen Ingoe, Roberto Pareyon, Kristine Italia, Marine Launay, Asma Salhi (PhD), Luke Gilliland, James Nielsen and Jashint Maharaj.
Affiliations: QUASR, the ARC Training Centre for Joint Biomechanics, QUT, St Andrew's War Memorial Hospital and The University of Queensland.
Read it
The paper is available on PubMed.
Related information
See our reverse total shoulder replacement page, and our posts on mixed reality for glenoid guidewire placement and robotic assistance.