ALTERNATIVES TO CONVENTIONAL SHOULDER REPLACEMENT
Conventional shoulder replacement or “total shoulder arthroplasty” is usually performed with a metal humeral implant with a stem and a ball after resecting the arthritic ball side of the joint and a plastic socket or cup that is cemented in after reaming down the arthritic socket. This total shoulder replacement surgery has had consistent results of good pain relief and functional increases performed for end stage osteoarthritis. Longevity has been reported to be from 15-20 years with a survival rate of 84-95 percent. However, a shoulder replacement is typically performed on patients greater than 60 years old with severe glenohumeral arthritis who have failed conservative care with ongoing pain and functional deficits. These patients are usually lower demand.
Figures A and B: Radiographic views of a shoulder with severe glenohumeral arthritis before (left) and after (right) a conventional total shoulder arthroplasty with a metal ball and stem on the humeral side and a cemented plastic socket.
Figures C and D: Intra-operative surgical pictures of the deformed arthritic ball of the humerus on the left and after resection of the ball and implantation of trial stem or broach on the right.
Figures E and F: Intra-operative pictures of the glenoid or socket. On the left with exposure of the arthritic socket and on the right after preparation with reamers and drilling holes for the implant.
Figures G and H: Intraoperative pictures of the cemented plastic socket on the left and impacted metal humeral head on the stem on the right.
What if a patient is much younger, perhaps in his or her 30’s, 40’s or 50’s, highly functioning, or even athletic and wants to continue his or her current activity level? Even those over 60 years old may have a high level of function or be involved in athletic activity and not a good candidate for a conventional total shoulder replacement. Why is this? With a conventional shoulder replacement, there is more bone taken or resected on the humeral or ball side. This can be an issue with younger patients that would need another surgery in the future to revise the shoulder replacement if they “wear it out.” There would be less bone available for the next surgery, and eventually another replacement may not be possible. On the glenoid or socket side, the patient’s high activity levels have the potential to loosen the conventional cemented component. Also, the results of a revision surgery are usually not as good as the first primary surgery. This is why there are different “alternatives” being performed and developed for those who are not ideal candidates for a conventional total shoulder arthroplasty. These options include Arthroscopic Biologic Total Shoulder Resurfacing (ABTSR), Humeral Head Resurfacing (HHR) and Glenoid Resurfacing (GR). These options can also include a combination of these procedures based on the patient’s age, activity level, and expectations. Some of these techniques are newer and do not have long-term studies or outcomes, but short-term results are promising. Below is a review of these options.
Arthroscopic Biologic Total Shoulder Resurfacing (ABTSR)
The arthroscopic biologic total shoulder is for patients younger than 55 years of age with flexible shoulders and who are still very active. This procedure is proffered for these patients over a conventional total shoulder replacement because it replaces the patient’s diseased anatomy with cartilage and bone transplant from a donor using matched fresh allografts. By using fresh osteochondral allograft, the cartilage viability is the highest within the first 21 days from harvest of the graft and allows the best chance for healing and incorporation of the graft. This has been reported in the literature in numerous studies, most commonly in the knee and ankle. There is no loss of bone as in a conventional total shoulder replacement with implants made of metal and plastic, and the rotator cuff is not violated. It is also an outpatient procedure that is performed arthroscopically, so it is a minimally invasive surgery. The recovery is faster with an arthroscopic total shoulder, and the time spent in physical therapy is less. This procedure is starting to be done around the country by orthopedic shoulder specialists skilled at arthroscopic surgery. I have performed the procedure in my practice, and the results are very promising. There is a recent published study of more than 20 patients, which has shown good outcomes and promising results. Right now, options for these patients are very limited. This procedure is minimally invasive and is the closest option for restoring a patient’s normal anatomy and alleviating the pain and symptoms associated with his or her arthritic condition.
Figures I and J: Arthroscopic pictures of severe glenohumeral arthritis before (left) and after (right) an Arthroscopic Biologic Total Shoulder Resurfacing with donor grafts.
Humeral Head Resurfacing (HHR)
This procedure has been performed for several years with a metal cap that is sized and placed specifically to the patient’s anatomy. The implant is “press fit,” which means on the part that contacts the bone it is coated and textured in a way that “grows into” the bone it is placed on. It has shown good short term and mid term results. It can be performed alone or in conjunction with a procedure with the glenoid. There is also a “partial” humeral head resurfacing available (Figure L) that can be performed if the arthritis or damaged cartilage is isolated to a region on the humeral head.
Figures K and L: A/P Radiographs of a shoulder with severe glenohumeral arthritis before (left) and after (right) a press fit metal Humeral Head Resurfacing.
Figures M and N: A/P radiographs of a Humeral Head Resurfacing and a partial Resurfacing.
Glenoid Resurfacing (GR)
This procedure is a relatively newer procedure that resurfaces the glenoid or socket side of the glenohumeral joint either with an “inset” glenoid component of either a plastic or poly implant or a fresh osteochondral allograft from a donor similar to the arthroscopic biologic resurfacing. With conventional total shoulder replacement, the glenoid implant is placed on the socket and cemented in (Figures E, F and G). It is more prone to “loosening” over time with very active and/or athletic patients. It can “rock” back and forth with more weighted stress over time. With an inset glenoid implant, there is less “rocking” and thus less potential chance for loosening. With fresh osteochondral allograft from a donor, there is maximal bone preservation. The decision to use either one is dependent on several factors, including the patient’s age, activity level, and a discussion of pros and cons with each individual patient.
Figures O and P: Intraoperative picture on left of a resurfacing glenoid poly and on the right a combination of a Humeral Head Resurfacing with a press fit metal implant and a resurfacing glenoid with a fresh osteochondral allograft from a donor.
Alternatives discussed here to a conventional total shoulder arthroplasty with metal and plastic include Arthroscopic Biologic Total Shoulder Resurfacing (ABTSR), Humeral Head Resurfacing (HHR) with a metal cap or partial implant, Glenoid Resurfacing (GR) with either an inset plastic implant or a fresh osteochondral allograft from a donor, and a combination of these procedures. Each procedure has its own pros and cons and depends again on the patient’s age, activity level, and expectations. Some of these procedures are new to the shoulder but have been used in other areas in the body such as the knee and ankle for years with good mid-term and long-term data and survivorship. There are other surgical options for younger patients with glenohumeral arthritis not discussed here, such as arthroscopic debridement, chondroplasty, capsular releases, decompression, and proximal biceps tenodesis to help alleviate symptoms. This may help for a period of time, but it is not a long-term solution. An arthroscopy may be performed first to help “buy time” for a younger patient. There has also been soft tissue allografts used on the glenoid or socket side such as donor meniscus and Achilles tendon with a metal implant on the humeral side, but this technique has not showed very good short-term results, and outcomes have shown high failure rates at three to five years. There is also a “ream and run” technique used on the glenoid that has its own pros and cons. The techniques described here have the potential to give younger patients and very high demand middle to older aged patients alternatives to conventional total shoulder arthroplasty for a longer term solution to continue their activity levels. These techniques can also be used to treat isolated lesion or unipolar lesion on the ball or socket side of the joint.