Shoulder arthroplasties, or replacements are not unusual, but regular replacements are not the right answer for many people. Some need what is called a reverse shoulder arthroplasty. This is mostly used for people who have injuries of the rotator cuff due to arthritis.
Reverse replacements put the ball of the joint just off the shoulder blade with the socket off the upper arm rather than the usual ball at the top of the bone and the socket on the shoulder blade.
Early designs of reverse replacements had mechanical failures. The authors of this study examined a technique that used locking screws on the baseplate and an adjusted center of rotation for the shoulder. They enrolled into their study 112 patients with 114 shoulders that needed repair. By the end of the study, they had 94 patients with 96 treated shoulders for evaluation. The average age of the patients was 72 years and the majority of patients (63) were women. Assessment before surgery included computed tomography scans (CT scans) and a videotape of the patients’ movements before surgery, using the shoulder moving forward, backward, and up and down. The patients were also asked to score their pain using the American Shoulder and Elbow Surgeons Score (ASES), the Simple shoulder test (SST), as well as reports of their overall satisfaction with their shoulder.
After surgery, the patients’ shoulders were immobilized for six weeks but they did perform pendulum exercises every day. After six weeks, the patients were allowed to use their shoulder and they began gradually use their arm for every day activities. They were only allowed to start strengthening exercises at three months after their surgery.
Upon reviewing the results, the researchers found that the average total ASES score improved from 30/100 before the surgery to 77.6 after. The average individual ASES scores rose from 15 before surgery to 41.6 after surgery. The average SST scores rose from 1.8/10 before surgery to 6.8 after.
When examining the patients’ range of motion, the researchers found that there were improvements in all angles and directions from before surgery and after.
There were some complications after surgery. Six patients experienced nine complications total. One patient fell three months after surgery and fractured the shoulder, but this was treated with immobilization. Another patient fell 27 months after surgery and needed surgery to repair the shoulder. One patient developed a severe infection in the shoulder, and three patients developed dislocations without trauma.
Eighteen patients were not followed up because they did not respond to follow-up requests.
The authors write that this procedure increases success with the patient outcome and limits the amount of mechanical failure.