The surgical repair of a rotator cuff tear has failure rates ranging from 20 to 90 percent. Even if the surgeon performs a technically perfect surgery some rotator cuff repairs will fail. Failure is defined as a recurrent tear.
Shoulder surgeons are unsure if the cuff repair never heals or it heals and then quickly re-tears after surgery. Typically at the time of surgery the rotator cuff is unhealthy to begin with which has contributed to it tearing in the first place. Research has documented that as we age, rotator cuff tears become more and more prevalent. What is not actually known is what rotator cuff repairs will fail. It would be extremely useful to have risk factors that could be identified at the time of surgery to predict which rotator cuff tears will heal without event and which ones are at high risk for failure.
Drs. Wu et al. published in the December issue of the American Journal of Sports Medicine a study looked to identify the risk factors that is noted at the time of surgery that can help determine which rotator cuff repairs will fail after surgery or will last.
The study involved 500 patients, a single surgeon, and an ultrasound evaluation of the rotator cuff repair 6 months post-operative. Dr. Wu et al. found that the best predictor of whether the rotator cuff repair would re-tear was based on the pre-operative rotator cuff tear size.
They found that tears that were less than 2 cm2 in size only had a re-tear rate of 16% compared to tears that were greater than 8 cm2. The larger pre-operative tear size of greater than 8 cm 2 had a re-tear rate after surgery of 57%. Statistically it can be stated that if the tear is less than 2 cm2 it is twice as likely to heal compared to tears that measured greater than 6 cm2.
Research has proven that when the rotator cuff tears it loses it blood supply and the rotator cuff tendon will start to degenerate. It becomes atrophic and less elastic. Therefore it makes sense that the bigger the tear at the time of surgery, the more of the blood supply has been lost and possibly the older the tear. All these factors make the rotator cuff tendon even less healthy predisposing the repair to failure.
For more info on shoulder injuries and shoulder conditions, see Orthopaedic Specialists FAQs on shoulder injuries and shoulder surgery.