Doctors are using a new, less invasive form of surgery to replace injured shoulders. The stemless shoulder replacement works particularly well in younger patients whose bones may not be as worn as those of older people. Dr. Anand M. Murthi, chief of shoulder and elbow surgery at MedStar Union Memorial Hospital, talks about the differences between stemless and traditional shoulder replacement surgeries.
What is a stemless shoulder replacement, and how does it differ from traditional shoulder replacement?
During traditional shoulder replacement, I have to "core," or ream, about halfway down the humeral [bone] shaft and insert a rod or stem. The humerus, the long bone in the upper arm, is located between the elbow joint and the shoulder. This adds to the risk of postoperative pain and postoperative fracture if the patient falls and breaks their arm below the very rigid stem. The stemless shoulder replacement uses a small "anchor" or "cage," without the traditional 6- to 7-inch rod driven into the humerus, to hold the humeral head or ball in position.
Who are good candidates for this type of replacement?
Patients with standard osteoarthritis, post-traumatic arthritis, rheumatoid arthritis and chondrolysis (disintegration of joint cartilage) are candidates for stemless shoulder replacement. Generally, any patient who is a candidate for traditional total shoulder replacement is a candidate for a stemless implant. However, the best candidates are younger patients with shoulder arthritis who have very good quality bone to hold the stemless implant in position. It would not be an advisable option for patients with severe osteoporosis or osteopenia [low bone density]. This condition could cause the anchor to be unstable when placed.
This procedure helps to preserve bone. Why is that important?
Bone preservation is crucial, especially in our younger working population. Should they need a second operation or revision in later life, there would not be much of the humerus bone left to work with. Bone preservation also potentially provides more comfort after surgery since we do not have to core out the humerus. Eliminating this step reduces the risk of a fracture around, through, or below the stem of a shoulder replacement. Obviously, if there is no stem, there is no risk of this happening.
Does this type of procedure allow for better mobility?
I believe my patients have less discomfort after this procedure, so postoperative therapy has been quicker and smoother, allowing for better mobility. Before surgery, typical patients with osteoarthritis have lost a tremendous amount of shoulder motion. Some patients cannot eat, wash or reach into high cabinets without severe pain. Furthermore, many of them have given up their favorite sports and leisure activities like golf, tennis and swimming.
This pain or discomfort is typically gone after the first week of surgery. Over the course of the first six weeks of recovery, they regain a tremendous amount of motion. Golfers can pitch and putt after six weeks, [use] long irons at three months and use the driver at four months. Tennis players can start ground strokes at eight weeks and serve at three months. Swimming can start as early as six weeks [after surgery].
Is this type of procedure more expensive than traditional shoulder replacement?
[Implant] costs are the same. However, the procedure is simpler and minimally invasive, therefore requiring less operating room time, which saves costs.
What are the potential risks for this type of procedure?
Theoretically there is a risk that the stemless implant could loosen from where it is placed. However, over 40,000 have been placed in Europe, and the risk is no more than loosening rates of traditional stemmed implants, which is less than 1 percent.