Shoulder arthroplasty to relieve pain has no greater risk of complications than replacement of other major joints

Apr 3 2007

Contrary to widespread belief, total surgical replacement of arthritic shoulder joints carries no greater risk of complications than replacement of other major joints, a Johns Hopkins study suggests.

In fact, the Johns Hopkins researchers say, their study shows that patients who undergo shoulder arthroplasty to relieve chronic and significant pain can expect significantly fewer complications, much shorter hospital stays and less costs than patients undergoing hip or knee replacement.

Arthritis is estimated to affect more than 16 million Americans and is a common cause of shoulder pain and mobility loss. However, many reject shoulder joint replacement, fearful of risks and costs. The Hopkins research team, led by Edward McFarland, M.D., director of the Division of Adult Orthopedics at The Johns Hopkins Hospital, analyzed anonymous patient information provided by the Maryland Health Services Cost Review Commission, the state's hospital rate-regulator. They looked at all arthroplasties performed in Maryland to alleviate osteoarthritis pain between 1994 and 2001, including details of 15, 414 hip surgeries, 34, 471 knee operations and 625 shoulder procedures.

"After looking at how all these patients fared, we concluded that, comparatively, total shoulder surgery is just as safe and effective as other types of arthroplasties," says McFarland. "Lower numbers of shoulder procedures done both regionally and nationally may indicate that many people live with shoulder pain because they fear that the corrective surgery is too risky or costs more than similar procedures. But we have found that this is just not true."

The findings appeared in a recent online version of the journal Clinical Orthopedics.

According to nationwide 2003 Medicare figures, 6,700 people had shoulder joints replaced that year, compared to 106,887 hip replacements and 199,195 total knee replacements.

Shoulder arthroplasty consists of placement of a metal and plastic artificial joint similar to the ball-and-socket construction used to substitute for hip and knee joints. The socket, or scapula, is scraped clean and fitted with a plastic mount, while the ball at the top of the humerus bone in the arm is replaced with a metal implant.

Patients in the study who had shoulder surgery had far less in-hospital post-surgical complications (7.5 percent) compared with those patients who had their hips and knees replaced (15.5 percent and 14.7 percent, respectively). McFarland's team also determined that the average time a person remained hospitalized after the surgery was lowest for those recovering from shoulder procedures (just 2.42 days for shoulder patients, versus more than four days for both the hip and knee equivalents).

Shoulder arthroplasty is also less expensive, according to McFarland. A shoulder replacement's total costs, on average, are $10, 351; whereas hip replacement surgery averages $15, 442, and knee arthroplasty, $14, 674.

In the study period, there were no fatalities associated with shoulder replacement, compared to 27 deaths among hip replacement patients and 54 among knee replacement patients. Given the small number of shoulder surgeries actually performed, McFarland noted that the mortality rates for the procedure were not statistically different from the other forms of arthroplasty. But finding no resulting deaths attributed to total shoulder replacement in the group of patients studied did add "clinical significance" to the idea that shoulder surgery is relatively safer. The study's authors suspect that the higher number of deaths related to hip and knee procedures may be related to repeat surgeries stemming from postoperative complications during the same hospitalization, a need for blood transfusions or extended intensive care stays.

McFarland says most patients who are candidates for total shoulder replacement surgery are "at the end of their rope" trying to manage chronic pain and disability with drugs. "Ninety-nine percent of the people who have a shoulder replacement for arthritis get pain relief and say that they wish they had done it sooner," says McFarland. "This study indicates there may be little reason to wait."