CHICAGO – Reverse shoulder arthroplasty provides a surgical option for improving pain and ability in patients who have both arthritis and massive rotator cuff tear.
Before the procedure was approved in the United States in 2005, patients with this combination of conditions were very difficult to manage. “We didn't have a solution for this problem for many, many years, but now I think we really do,” said Dr. Matthew Saltzman, an orthopedic surgeon specializing in shoulder and elbow surgery at Northwestern University, Chicago.
Reverse shoulder arthroplasty basically changes the mechanics of the shoulder. It involves putting the ball in the socket, and putting the socket where the ball used to be, he said, adding that it's “a strange concept, but it actually works.”
“With reverse shoulder arthroplasty, you're actually medializing the center of rotation, and this can be done to varying degrees depending on the implant design,” he said, explaining that the procedure changes the tension on the deltoid muscle and allows the deltoid, rather than the irreparable rotator cuff musculature, to lift the arm.
Dr. Saltzman described two cases involving elderly women who underwent the surgery and had excellent outcomes at 6–12 months. One was an 84-year-old who presented with a massive cuff tear as well as arthritis-related joint damage and loss of the joint space. Like many patients with these conditions, she had severe pain, pseudoparalysis of the shoulder, and resulting lack of function; she was able to lift her arm to only about 20 degrees.
At 6 months after the operation, she had no pain and was able to elevate her arm and rotate the arm out to the side.
The other patient was an 86-year-old who had previously lived independently, but who had slipped on ice and sustained multiple fractures of her shoulder. Although her problem wasn't arthritis related, the reverse shoulder arthroplasty was successful, and she was able to return to independent living.
Findings from a study involving 240 consecutive reverse shoulder arthroplasty procedures in 232 patients (average age, nearly 73 years) showed that average forward elevation increased from 86 degrees to 137 degrees, and average constant score (a validated measure of shoulder function) improved from 23 to 60 at the latest follow-up, indicating substantial improvement, Dr. Saltzman said (J. Bone Joint Surg. Am. 2007;89:1476–85).
In that study, patients with cuff tear arthropathy, osteoarthritis plus cuff tear, or massive cuff tear fared better, whereas those with posttraumatic arthritis and those undergoing revision arthroplasty had worse outcomes.
Dr. Saltzman disclosed that he serves on the speakers bureau of Carefusion, has made paid presentations for DJO Surgical, and has received research support from Arthrex.