Studies show that massive (very large) rotator cuff tears are at great risk of retears. There is evidence of a retear rate as high as 94 per cent. In a recent study from the University of Michigan in Ann Arbor, surgeons took a look at the timing of the tears to see if this might help explain situations like yours.
What they found might help you understand your own retear. They hoped to see if the timing of the tears might offer some clues as to the reason for the tears. Tears that occur early after surgery might be an indicator of a mechanical failure of the surgery itself.
They thought that perhaps the type of sutures used or the way the stitches were put in place contributes to mechanical failure. Some studies have pointed to the way the soft tissue attachment is prepared at the start of surgery. This area is called the footprint — the place where the rotator cuff pulls away from the bone.
Another thought about the timing of tears has to do with biologic failure. This has more to do with the tendon healing where it is repaired or reattached to the bone. There is some thought that if the healing tendon can be protected long enough from stress, strain, and overload, then the patient is much less likely to retear the repair.
What they found with this study was a high rate of early ruptures. The tears occurred while the patients were still in a sling. They had not even started moving the arm or seeing the physical therapist yet. This points to the strong possibility of the repair itself being the problem (a mechanical failure where the suture and tendon interface).
There weren’t any tears after six months, which supports the idea that once the repair is healed, unless there is a biologic weakness in the repair, the surgery should hold up quite well. Some studies have shown that the use of antiinflammatory drugs may have a negative impact on where the tendon is reattached to the bone. So this could be a factor as well.
It isn’t always possible to know when a retear has occurred. Many patients have retears that aren’t painful or problematic. The fact that your repair started bothering you after rehab and during your home program phase suggests a biologic reason (e.g., poor tendon healing) but don’t necessarily prove it.
In cases where the failure doesn’t occur until three months after rotator cuff repair, points more to a failure at the tendon-bone interface. There may not have been enough true tissue healing to hold the repair. And that raises a whole new set of possible risk factors (e.g., your age, your general health, the presence of other complicating health problems such as heart disease or diabetes).
In the end, it may not be possible to determine cause and effect. It’s likely there isn’t a single factor (mechanical or biologic) but rather, several combined together. As the surgeons who performed the University of Michigan study pointed out, at this point, all we really know is that there are some mechanical (surgeon) and biologic (patient) issues related to the surgical procedure that must be investigated further.