You may have developed a complication of arthroscopic surgery called chondrolysis. Chondrolysis is defined as a generalized (all over) loss of the articular (surface) cartilage of the joint.
The fact that the condition is generalized (rather than a local area of cartilage loss) shows that this is more than just a mechanical problem. If it were a suture rubbing away the surface cartilage, then only one or two bare spots would form.
But when the entire surface of the humeral head (round ball of bone at the top of the upper arm) and the inner layer of cartilage in the shoulder socket are missing, then it’s time to take a closer look.
A recent study about this problem was done at the University of Washington in Seattle. It is the largest study of its kind and probably the first to look at risk factors for chondrolysis after shoulder arthroscopic surgery.
They found that 19 per cent of the patients who had arthroscopic shoulder surgery developed symptoms of chondrolysis within 18 months of the procedure. After analyzing all the data, they were able to see three potential risk factors.
Most notably, it looks like injecting a specific numbing agent (marcaine) into the joint at a high enough dose (0.5 per cent) is the most significant risk factor. Pain and loss of shoulder motion were the first symptoms reported. The pain began within the first 18 months after shoulder surgery. In all cases, marcaine was injected into the joint after the procedure.
Anyone who had shoulder surgery without the use of an intra-articular (inside the joint) injection did NOT develop chondrolysis. Likewise, when a lower dose of marcaine (0.25 per cent) or a different drug (e.g., lidocaine) was used there were no reports of chondrolysis.
A couple other factors were identified as increasing the risk of chondrolysis after intra-articular injection of marcaine. The use of suture anchors in the glenoid (shallow groove, shoulder socket) was one risk factor.
Younger patients were also more likely to develop chondrolysis after intra-articular injection of marcaine following arthroscopic shoulder surgery. The link between age and chondrolysis isn’t clear.
Surgeons have found that reducing pain after shoulder surgery helps speed up recovery. As a result, more aggressive pain control measures are now in use. One of those methods is to inject a local anesthetic (marcaine, lidocaine, bupivacaine) directly into the joint after surgery.
This study shows that the practice of postoperative infusion of marcaine actually contributes to the destruction of the joint surface. There may be other risk factors or a combination of reasons why this condition develops after shoulder arthroscopic procedures. Clearly, you are not alone and every effort is being made to pinpoint and prevent the problem for others.