Botox for Knee Pain? Be Careful What You Wish For.

Recently I blogged about an article written by an accomplished doctor, in which he mentioned this Mayo Clinic study about the relationship between quad strength and cartilage loss.

The same article also mentioned something I’d never heard of: Botox for knee pain! Naturally I was intrigued. I didn’t do extensive research into the subject (alas, I don’t really have time to do much research into anything these days), but I read enough to have a few thoughts worth sharing.

First, the Botox study isn’t exactly new. As noted by Arthritis Today (which summarized the findings), the results were presented at the American College of Rheumatology’s Annual Scientific Meeting in 2006. For the study, neurotoxins (which is what botulism is) were used to target “the pain nerves within the joint.”

Over six months, 37 patients with moderate to severe knee pain received either a  placebo or Botox injected into their knee joints. The 18 patients with severe pain experienced a “significant decrease in pain and improvement in physical function” after the Botox shots, compared with the placebo group. Oddly, for those with moderate pain, the placebo group had a 25% reduction in daytime pain while the Botox subjects had no benefit.

So, does this mean Botox isn’t just for your forehead wrinkles anymore? If so, should we celebrate?

Maybe not. Because what is Botox? A toxin. A toxin that does what? According to this ezine article, “When Botox is injected into the muscles of the forehead, it blocks nerve impulses which results in the weakening of the muscles that cause frowning."

Sure, it would be great to banish knee pain. But Botox does it by basically disabling your nerves. That’s fine if your nerves don’t perform any useful function. But of course they do.

Your nerves give you constant feedback about what you shouldn’t be doing with your bad knees. Eliminate that negative feedback, and I’m sure you'd feel better, but at what price to your joints? If I removed the right set of nerves, I’m sure a knee pain sufferer with bone-on-bone arthritis could run a 10k road race without feeling a thing -- while doing terrific damage to his joints.

If the preceding has a familiar ring to it, that’s because this is basically a variation on my argument “why I don’t like pain meds for knee pain.” Of course, sometimes there really is no choice -- I don’t mean to sound unsympathetic.

But the long process of healing from chronic knee pain, I found, involves a very tricky sort of calculus. You need to find, and stay within, your "sweet spot," that area of maximum motion where you move as much as possible, but not more than your knees are ready for. It’s hard enough to find that "sweet spot" as it is. Without fully functioning nerves to guide you, it seems it would be nearly impossible.

So be careful what you wish for. The only thing worse than a life with knee pain may be a life without any knee pain -- if that pain is sending you signals that help you figure out how to get better.