In order to help patients with cuff tear arthropathy, a shoulder injury, many surgeons were settling for partial shoulder replacements, cautioning their patients not to expect full rehabilitation because the surgeons found that the other types of replacements were causing problems. However, researchers began looking into the use of a reverse shoulder prosthesis as a new type of surgery that could offer better results. The reverse procedure literally reverses the ball and socket that are replaced.
Until now, the largest study that looked at reverse arthroplasty (replacement) involved 80 patients with a cuff tear arthropathy, a tear in the part of the shoulder that holds the bones together. Patients had a good response to the surgery, with 96 percent claiming little or no pain at 44 months follow-up. Reverse total replacement has also been performed for other shoulder problems, such as revisions of previous replacements, after tumor removal, and to repair damage from rheumatoid arthritis. The authors of this study wanted to see if the results of this type of surgery were affected by the type of injury that the surgery was meant to correct.
Researchers found 232 patients (average age, 72 years, ranging from 28 to 86 years), who had had this procedure done at one institution between May 1995 and June 2003. The reasons for the surgery included: rotator cuff tears, rheumatoid arthritis, osteoarthritis, fractures, and replacement revisions. Among the 232 patients, 240 procedures were done because 8 patients had both shoulders replaced. The majority of the surgeries (184) were on women.
To evaluate the effectiveness of the surgery, the researchers collected data with x-rays, computed tomography images (CT scans), and range of motion, before and after surgery, as well as Constant scores. The patients were asked to rate their overall experience.
The patients used slings for 1 month after surgery although they were allowed to take them off to do daily activities, as long as there was no lifting. After 1 month, the sling was removed and the patients resumed normal activity to their tolerance. Final data were collected on 191 shoulders in 186 patients. The average Constant score was 22.8 points before the surgery but 59.7 at follow-up. Patient from all shoulder groups showed an average improvement of elevating their arms to 137 degrees after surgery from 86 degrees before surgery.
When the patients were asked to grade their experience, 59.7 percent said that they were very satisfied, 33.3 percent were satisfied, 5.9 percent were uncertain, and 1.1 percent were disappointed.
The patients with cuff tears and primary osteoarthritis seemed to do the best after this surgery than did patients with post-traumatic arthritis and those who were having a replacement revision. Other findings showed that the benefits seemed to be stable after 3 years. When looking at complications, 8 patients in the original group were included, bringing the total number 199 patients for this calculation. The most common complications were dislocation (7.5 percent) and infection (4 percent). Complications such as fractures, hardware breakdown, and others were infrequent.
Those patients who had revision surgeries appeared to have a higher risk than did those patients who were having the surgery for the first time. The total complication rate of 19 percent was lower in this study than in others.
The authors point out that their study was limited because there was no direct comparison between these patients and those who underwent other treatments and follow-up was short, only 2 years. However, the authors conclude that this procedure can be used for patients with cuff tear arthropathy and other shoulder problems, although the approach should be done with caution when these prosthesis are being used for difficult cases.