Innovations in Reverse Shoulder Design Expand Indications and Improve Outcomes

[mtomaino]

On Monday November 15th (2010) I spent the day at Tamp General Hospital with Dr Mark Frankle, the designer of the DJO RSP "Reverse Shoulder Prosthesis". Besides being credited for his innovative design, Mark has published more on this procedure than anyone in the world, and his clinical experience is second to none. Like the majority of surgeons who perform reverse shoulder arthroplasty, I have repsected many of the original tenets advanced by Dr Grammont--the originator of the original design. These include a MEDIAL CENTER OF ROTATION, to keep the glenoid loads lower, and a more valgus neck shaft angle on the humerus (155 degrees). In addition the the Ball being on the socket, and the socket being on the ball, these design features are, in large part, why this prosthesis is considered "Nonanatomic".

Dr Frankle dared to question these original tenets, and has, through numerous scientific articles, shared his research with those who are open-minded enough to listen. In particular, he has shown that a LATERAL CENTER OF ROTATION is more anatomic, and in combination with a more varus neck shaft angle (135 degrees), better motion may result, including abduction and external rotation, because of less impingement by the humerus. Further, he has shown most recently that his baseplate design, which includes screw fixation, withstands the increased forces on the glenoid.

Over the past 2 years I have been, and continue to be extremely satisfied with the Reverse prosthesis I hve been using (Tornier). So why visit Dr Frankle??

The first reason is obvious to me----he is a leader and innovator. My own endless development requires an active dialogue with other "though-leaders", who by their own experience and vision, challenge the status quo. Second, Dr Frankle's design allows reconstruction of the most challenging cases---deficient glenoid bone stock and instability--because of the baseplate design and screw fixation feature, and lateral center of rotation and varus neck shaft angle, respectively.

Providing the best outcomes for patients in Rochester and Upstate New York is better enabled by understanding the role of different Reverse Shoulder designs. In that light, I am indebted to Dr Frankle for sharing his experience and insight with me earlier this week.