More Evidence on the Limits of Surgery

What would you do, if you were a surgeon, and a knee you happened to be operating on for an ACL tear was found to have deep cartilage lesions?

This seems like a no brainer, right? You’re already inside the joint. You see damaged cartilage. Why not fix it, to the best of your ability?

Well, what if your intervention makes absolutely no difference.

Check out the findings of this study.

Between 1991 and 1995, 43 patients were treated during surgery for tears of the anterior cruciate ligament but not for associated cartilage lesions. The defects were significant too: Outerbridge grades 3 and 4, signifying that at least half the cartilage, and sometimes all of it, had worn away at a given location.

The study’s researchers followed up with the subjects 10 and 15 years after the surgery. Outcomes were compared with those of a matched group who had the same operation performed, and who went through the same rehab program, but who didn’t have any cartilage lesions.

The difference?

None.

There was absolutely no disadvantage to leaving those severe lesions untreated.

In fact, there may have been an advantage. Because consider this: The best possible outcome should be that of the group with ACL tears but no lesions. But the group with ACL tears and lesions that were left untreated fared as well as this “gold standard” group.

That leaves one group that wasn’t included in the study: patients with ACL tears and treated lesions.

How would such subjects have done? It’s impossible to know, but they couldn’t have done any better than the other two groups, be definition. There’s no way that a surgeon can “fix” cartilage defects in a way that makes them better than what they were before the tissue was damaged. But it’s possible that these people might have done worse. Yikes!

One of the authors of the study, Wojciech Widuchowski, said in a presentation (my bold):

Our conclusions are these cartilage lesions found during ACL reconstruction left with no treatment do not appear to affect the clinical outcome at 10 and 15 year follow-up. Our study seems to reinforce the question whether treatment of a symptomatic lesion provides improvement over that of the natural history.

So the study has good and bad news:

(1) It’s pessimistic about the ability to improve areas of bad cartilage in the knee joint by using surgery to “clean up” or otherwise fix them.

(2) It’s optimistic about the ability of knees with damaged tissue to do acceptably well on their own (Note: that’s what the results seem to suggest anyway).