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.

[Maryann]

Since authoring my post above, I have had the opportunity to use the DJO Reverse prosthesis in 4 revision cases--- each performed in paients with severe pain due to worn glenoid cartilage in the aftermath of humeral replacement (hemiarthroplasty).

Because the humeral cut for this design is more varus than the cut for "Grammont design" reverse prostheses ( 130 compared to 150ish), there are 2 effects. The first is that there is less risk of scapular impingement with the arm at the side. Although it is true that the observation of "scapular notching" has not been linked to poorer functional outcomes, there is little question that a "more anatomic-- varus-- cut" also minimizes impingement at the extremes of rotation; thus, functional range of motion may indeed improve with this design.


In most cases where Reverse arthroplasty is performed, the indication is "cuff arthropathy" or an irreparable rotator cuff without arthritis. As more and more patients with failed hemiarthroplasties with in tact cuff present, the DJO design has an additional value proposition. The steeper (more anatomic) humeral cut allows preservation of the infraspinatus insertion--and this may improve functional external rotation. And, patients may have improved internal rotation (behind the back motion) as well.

I will continue to provide updates; but after 4 revisions this month alone, I am enthusiastic about improved outcomes for patients who require Reverse arthroplasty.


MERGED RELEVANT POST

As I have just had my second reverse revision shoulder replacement I invite anyone who
is contemplating this type of surgery to contact me. I have 2 very unique prosthesis, and what i consider to be the best of both worlds. My second replacement was in January
and I am now in active PT for the next 2 months. Yes, a major operation with a major
committment- but the best decision I could have made. Pain relief is so much better, and with time and plenty of effort the range of motion improves. Dr. Tomaino is the best!!!
Thanks to him I will have many years of shoulder relief. Maryann M.

[mtomaino]

Yesterday I saw a patient who has had severe Right shoulder pain for nearly 2 years since he underwent a shoulder hemiarthroplasty after a comminuted proximal humerus fracture.
Unfortunately his component is loose, and he has no function because his tuberosity fragments did not heal and resorbed.

I have attached his current xrays. This patient is an excellent candidate for revision to a Reverse design. In addition, he may benefit from th use of Humeral allograft. For more information on managing proximal humeral bone loss, visit this link:

http://www.rearmyourself.com/article...al%20Bone-Loss

[Barnman]

I have a couple questions about Reverse Shoulder Replacements.

1. If you have a reverse shoulder replacement and it goes its life span, whatever number of years it might be, Can you have another reverse shoulder replacement done?

2. Is there a report that you can direct me to that compares the life expectancy of JCO/Encore vs. other models?

[mtomaino]

Thanks for your questions:

1. If you have a reverse shoulder replacement and it goes its life span, whatever number of years it might be, Can you have another reverse shoulder replacement done?

Yes---so long as there is no active infection or severe loss of bone stock. Your question really gets to the question of "Do you burn a bridge in having a Reverse now, as opposed to putting it off and living with pain?"

In my experience with primary Reverses as well as Revisions to a Reverse because of failed Hemiarthroplasty, pain relief is nearly complete; and a secondary benefit is the ability to raise the arm in the plane of the scapula to at least 90 degrees, and more commonly to 120-135 degrees. This greatly improves function. Now, if there is a complication such as instability or loosening, these can be addressed by reoperation. However, as techniques improve----these complications have been diminishing.

I say to my patients that our goal is a 10-15 year period of pain relief and improved function. Though it appears that function may begin to decrease after around 7.5 years (this is based on an outcome study by Dr Giles Walch, who uses a Grammont design). patients are still doing better thn before the operation.

2. Is there a report that you can direct me to that compares the life expectancy of JCO/Encore vs. other models?

No. But I have attached an article published in the J Shoulder and Elbow Surg in jan 2011 which addresses such things as glenoid loosening and scapular notching.

Visit this link:
http://www.rearmyourself.com/article...20Arthroplasty

The survival rates of an anatomic type of total shoulder design at 10 years is 92%; a hemiarthroplasty is more like 72%. I expect that with current techniques the Primary Reverse will have a 10 year survival in the 90's--------but that function may decline over time. The humerus should be no different with the Reverse; the glenoid baseplate, by contrast, might loosen with time----in that regard, the lower rate of scapular notching with the DJO design as compared to the Grammont design may bode well for the former regarding survivability.

[mtomaino]

Visit this link for a recent video patient attestation following revision, and see my comments dated March 5,2011 :

http://www.rearmyourself.com/article...miarthroplasty