Hi, good day. My name is Peter Millett. I'm here to talk to you about treating glenohumeral osteoarthritis in young patients. We'll talk about arthroscopic treatment and interposition arthroplasty. My disclosures can be found on the Academy website. As you know, glenohumeral osteoarthritis is certainly challenging to treat in younger patients. Total shoulder arthroplasty is associated with inferior results because of issues about component loosening, risks of revision, and long-term component survival. So what's the best choice? Well, we did a Markov decision analysis looking at patients who have glenohumeral osteoarthritis. And what we found is that patients who are less than age 47, arthroscopic treatment is preferred. Above age 66, arthroplasty is preferred. And in the middle, both are reasonable. So you need to take into account the patient's desires, their goals, their occupational demands, recreational demands, as well as pathoanatomic features to choose the best treatment option. Arthroscopic treatment has been used for many years. We've kind of built on this with a procedure we call a CAM procedure for comprehensive arthroscopic management. In addition to the standard arthroscopic techniques of debridement, it additionally includes removing the goat's beard deformity with an inferior humeral osteoplasty, releasing the inferior capsule and then indirectly and directly decompressing the axillary nerve. The indications for the CAM procedure are patients with advanced symptomatic osteoarthritis who are young or very active and they desire joint preservation as opposed to arthroplasty and they've always failed non-surgical treatment. The contraindications if they have severe osteoarthritis, obviously total shoulder arthroplasty is better. Relative contraindications which we've learned over the years include less than two millimeters of joint space, severely limited passive range of motion due to joint incongruity, large osteophytes which would be technically impossible or challenging to remove, bipolar disease, severe low critical shoulder angles, and then severe Kellgren-Lawrence scales of three and four, as well as deformity of the glenoid with Walsh B2 and C glenoids. The humeral osteoplasty is the unique part of this procedure. We use a beach chair position. This is a posterior viewing portal with a posterior infralateral portal. This is a shaver coming in, removing the goat's beard deformity. We use intraoperative fluoroscopy to assist with the resection of the inferior spur to ensure that we've completely reshaped the humerus. Here you can see the viewing portal from posteriorly. We're in the axillary pouch. Now we'll come in with a shaver, remove all the synovitis, and then we can remove this goat's beard deformity using a combination of the shaver, arthroscopic burrs, rasps, as well as curettes, and then we can remove all this debris piecemeal and remove any loose bodies that we find in the shoulder as well. The axillary nerve can be quite close. As you see in this arthroscopic image here, we're using a curette to remove the spur. The axillary nerve is right under the capsule there. We tend to keep the capsule intact, but you can see how this axillary nerve can be compressed by the spur, and we've done some MRI studies showing that the axillary nerve's course is actually displaced by the spur, and that's one of the theories about why this can help with patient's pain relief. In addition, we also will address pathology with the biceps as well as in subacromial space. Typically, we'll perform a capsule release after we've done our osteoplasty to avoid extravasation of fluid. Our results, this is our initial results. We had pretty good success at a minimum of two-year follow-up, and this encouraged us to go on. The concern was whether these patients were just coping with it. So we looked at a minimum five-year results, and what we found is that at five years we had about a 76.9% survivorship using a Kaplan-Meier survivorship analysis in 49 patients. About a quarter of the patients did go on to arthroplasty at an average of about 2.6 years. We now have minimum 10-year outcomes. Justin Arner, who's in practice in Pittsburgh with Jim Bradley, has looked up my patients. He was a fellow with us last year. 38 patients at a minimum of 10-year follow-up. We had a 63.2% survivorship at 10 years. The progression to arthroplasty was at a mean of 4.7 years in 15 patients out of 38. And what we also learned is that in addition to glenoid abnormalities, that humeral head incongruity and severe flattening of the humeral head was also associated with failure. So we take that into consideration now when we're counseling our patients. Here's just a case example. This is a professional ultimate fighting champion fighter, former world champion. One year of left shoulder pain. He had a prior labral repair in 2011. Significant pain and loss of motion despite a variety of conservative treatment. Here's his preoperative range of motion. You can see he's limited in forward flexion, abduction, and external rotation. And here's what his preoperative x-ray looks like. You can see the severe large goat's beard deformity. It's taking up space. It's compressing his axillary nerve. He has pretty good congruity of the joint, however. Axillary view, you can see some early wear on the glenoid as well. Here's his MRI showing that his rotator cuff was intact and he had glenohumeral osteoarthritis. Here you see his preoperative x-ray again with the AP view. And here you can see his postoperative x-ray after the CAM procedure at 18 weeks with removal of that goat's beard deformity. We also did a biceps tenodesis on him as well. And here you can see his postoperative x-ray. The axillary view looks like maybe there's some reconstitution of some joint space, perhaps due to either some fiber cartilage that formed or maybe it's just due to the capsular release that was performed. Here's his two-year follow-up. He's given us permission to use all these videos. You can see his forward flexion, full motion now, symmetric. And it's his left shoulder that we operated on. He's quite pleased. He has good abduction, good internal rotation, good external rotation. And here's his sparring video that he shared with us recently as he's preparing for a fight in the next few weeks. So you can see here he's been able to restore great motion and function to his shoulder after a CAM procedure. So moving on, interposition arthroplasty is another option that's been used. This has been used in a variety of joints. Same concerns in young patients with long-term issues with arthroplasty, particularly on the glenoid side where we've seen some early glenoid failures in young patients. Krishnan looked at this a number of years ago and really gave us some encouraging results. This was humeral hemiarthroplasty with a prosthetic replacement with a biologic glenoid resurfacing. In this case they used mostly Achilles allografts. 36 shoulders, mean follow-up pretty long, 84 months, and very good restoration of function and decrease in pain with a postoperative ASES score of 91. They did have a few complications but in general this gave us some really encouraging results. Other authors have not been able to find such encouraging results. This is a study from El Hassan looking at JP Warner's patients in Boston with resurfacing of the glenoid with soft tissue and a prosthetic hemiarthroplasty for the humerus. Follow-up was 48 months and in this series 10 of the 13 failed and the average failure rate was by 14 months. Another more recent study looking at this, humeral head arthroplasty and meniscal allograft resurfacing of the glenoid. This is from Boyce with 26 shoulders in 26 patients, mean follow-up of 8.3 years. ASES scores went from 31.6 to 59, so an improvement but not really a great ASES score and the estimated 10-year survival rate was only 56%, so not as good as we would expect either with a CAM procedure or with a conventional total shoulder arthroplasty. More recently people have looked at doing this arthroscopically. This is a study from Hartzler and Burkhart where they looked at interpositional human allografts without a hemiarthroplasty, so they left the humeral side alone. 43 shoulders, mean follow-up of 53 months, minimum of 48 months and very good pain relief with a visual analog score going from 7 to 2 and ASES scores improving from 47 to 76, so a little bit better and certainly encouraging because you don't have to take the subscapularis down and you're not compromising an arthroplasty as much. They did have about a quarter of the patients, 23% that went on to a revision prosthetic arthroplasty at a mean of 45 months. Finally Puskis, 17 patients had hemiarthroplasty in combination with some type of soft tissue interposition. They compared the different types with a dermal allograft, capsular interposition or meniscal allograft. None of them really had great results. The dermal allograft, 5 of the 6 progressed to total shoulder. The capsular interposition, 4 of 6 progressed to total shoulder. And the meniscal allograft, 3 of the 5 progressed to a total shoulder. The mean was about anywhere from 16 to 34 months, so not really that durable long term. So in summary, I think the CAM procedure and arthroscopic approach is reasonable to delay or avoid the need for total shoulder arthroplasty. We can certainly manage the mechanical cause of pain. We don't really burn any bridges. It retains the normal anatomy. It is somewhat technically challenging from an arthroscopic perspective, particularly if you're going to remove the inferior osteophyte or perform an axillary nerve neurolysis. And our 10 year survival rate using Kaplan-Meier analysis is about 63%. So you do need to have a conversation with your patients that not all of them are going to do great and that some of them may need shoulder arthroplasty. Hopefully with using some of the predictors that I outlined, you can better select which patients will do well. And it certainly has promising results in young and highly active patients like that case example of the mixed martial arts fighter that I showed. Interposition arthroplasty is a great option to delay or avoid the need for total shoulder. It does utilize a graft to reconstruct the articulating surface. You should be aware that there's high revision rates and the complications are not uncommon. The 10 year survival rate is about 56%. Perhaps with arthroscopic approaches we'll have better outcomes and maybe combining a CAM procedure with interposition arthroplasty will be what we do in the future. So in conclusion, I think arthroscopic approaches or interposition arthroplasty are reasonable for young patients that are active. It's important to understand the complications and revision rates are not inconsequential. And you should be aware of this as an option for younger or very active patients with physically demanding occupations and recreational desires who really desire to avoid shoulder arthroplasty. Thank you very much for your attention and it's great to be part of this symposium for ANA.

glenohumeral osteoarthritis

arthroscopic treatment

CAM procedure

shoulder arthroplasty

interposition arthroplasty