Q: Three years ago, I had a very severe rotator cuff tear repaired. When I went in for a check-up the surgeon did a follow-up X-ray and ultrasound of the shoulder. Found out the tendon never really healed but I'm still much better. How do you explain that?

A: According to a recent study from Washington University in St. Louis, adults with very large tears of the rotator cuff (the four tendons/muscles surrounding the shoulder) can get pain relief and improved function after surgical repair -- even if the tendon doesn't heal. It was a small but still significant study of 18 patients who were followed over a two to 10 year period of time.

Results reported two years after the arthroscopic repair were re-measured 10 years after the primary (first) surgery. Like your surgeon, the lead surgeon in the study used ultrasound and X-rays to see what was going on in the shoulder. Patients also gave a self-report of pain, motion, and function. That's when the surgeons discovered two things.

First, the results were the same at the 10-year post-operative time as compared with results two years after the surgery. That means the patients were able to maintain outcomes without further decline. And second, a failed healing in 17 of the 18 patients didn't keep them from improving and holding that improvement steady over the years.

X-rays and ultrasound studies done on 11 of the original 18 patients confirmed the continued presence of rotator cuff tears. In a couple of patients, the tear was worse. There was no change in four shoulders and four patients actually had a decrease in the size of the tear. In all 11 cases, the head of the humerus had migrated (moved) up out of the natural resting place where it should be in the shoulder socket.

The bottom-line is that despite evidence of worsening of the soft tissues and shoulder joint, the majority of patients still had improvements with the surgery. Other studies have shown that with severe rotator cuff tears, the damaged area fills in with fatty tissue. It's not clear yet why improvements are maintained despite degenerative changes in the shoulder after repair of rotator cuff tears. But the pain relief offered and improved motion and function may make it worth having the procedure anyway.

Reference: E. Scott Paxton, MD, et al. Clinical and Radiographic Outcomes of Failed Repairs of Large or Massive Rotator Cuff Tears. Minimum Ten-Year Follow-up. In The Journal of Bone and Joint Surgery. April 2013. Vol. 95A. No. 7. Pp. 627-632.