What To Do If Your Physical Therapist Recommends That You Do One-Legged Dips

As most of you know, I try to refrain from giving advice on bad knees. I'm not a doctor, nor am I a physical therapist. Then there's the fact that even if I were, I haven't examined or even laid eyes on your particular knees.

So, generally, I'm not going to second-guess a treatment regimen prescribed by someone who has actually inspected your knees and discussed them at length with you.

However ...

In creeps a little exception.

I have become aware of at least two cases where patients with painful knees have been told to do one-legged dips as part of their exercise routines. (If you've never done one: While balancing on one foot, you bend your leg, dipping down, while trying to maintain a straight line.)

Let's imagine that your buff physical therapist advises you to do one-legged dips to help fix your ailing knees.

Here's what you should do after he says this:
 
Look into his face. Is it flushed? Are his eyes bloodshot? His pupils dilated? His breathing stertorous? These all can be signs of recreational, judgment-impairing drug use.

Surreptitiously gauge the distance to the door. Could you beat him to the door, even with your bad knee(s), if he made a move to try to restrain you and force you to do a couple of one-legged dips "just for practice"?

If he does suggest you try doing one under his careful supervision, demur gently, perhaps with a line such as, "Oh, maybe not right now, I just ate -- why don't you show me and I promise I’ll do a few as soon as I get home?" (Make sure your fingers are crossed behind your back.)

After your visit ends, when the receptionist says, "And when would you like to schedule your next appointment for?", snap your fingers as if you just thought of something. Then say, "Ah, you know, I just remembered my work unit is being transferred to Tokyo. Oh well! Sayonara!"

Okay, seriously now: I can't think of a good reason why someone with chronic knee pain -- someone who probably has some difficulty climbing a set of stairs -- should be encouraged to do a tricky exercise that involves balancing while putting his or her entire body weight on a weak and possibly unstable knee joint.

Before anyone jumps up and says, "Oh, I know why physical therapists prescribe one-legged dips!" let me be clear: I'm pretty sure I know why they do. In brief, it's basically structuralist thinking run amok. So that's not the issue.

If you really care about fixing your bad knees, the issue is that you have to slowly ease them back to greater and greater strength. The key to getting better isn't doing some demanding exercise that many people would struggle to do with fully healthy knee joints. That just strikes me as absurd.

Can Prolotherapy Help With Knee Pain?

I’ve written very little about prolotherapy. The idea sounds intriguing and promising: Create a minor irritation in knee joint tissue, through injections of a substance such as sugar water, and stimulate the body’s own healing process. Doug Kelsey seems to be a fan, which is a good sign. But I’ve refrained from writing about it because I don’t know much about the treatment or how effective it’s proven to be.

Well, here’s some good news.

Knee pain appears to decrease up to one year after “prolotherapy,” a series of sugar water injections at the site of the pain, according to a new study.

The study included 90 knee osteoarthritis sufferers, ages 40 to 76, who were randomly assigned to one of three groups. The first group received sugar-water prolotherapy injections, the second salt-water placebo injections, and the last set of subjects were just shown how to do at-home exercises. The injection groups got at least three shots over 17 weeks, and were monitored over a year.

The results: The prolotherapy subjects improved 16 points on a 100-point scale for knee function (compared with a gain of 5 points for the saline group and 7 points for the exercisers). When it came to reporting less frequent and less severe pain, the prolotherapy group impoved 16 points on the same scale, compared with 7 points for the saline injected and 9 points for the exercise group.

Hmm. Sure sounds good. Also the researchers said the study, though small, was not too small.

Is it worth giving prolotherapy a whirl, if your knees are stubbornly resistant to getting better? I’d certainly consider it. Anyone out there who’s had prolo who wants to chime in?

Note: Unfortunately, I should add a bit of a negative footnote. Prolotherapy treatments cost $200 to $1,000 apiece, and they’re not covered by Medicare. I’m not sure about private insurance though.

What Implications Does “Envelope of Function” Have for Designing a Plan to Beat Knee Pain?

Last week I described Scott F. Dye’s common-sensical idea of the “envelope of function.” He believes that patellofemoral pain patients should try to “maximize the range of painless loading for a given symptomatic joint (envelope of function) as safely and predictably as possible.” Such an idea is consistent with my own belief in slowly strengthening a damaged joint.

This week, I want to consider implications of the “envelope of function” perspective. In other words, how does it translate into practice?

At the end of this post, I’ll tell you what Dye himself recommends for treating achy knees.

Before that, I want to share my own observations about what “envelope of function” implies.

But even before that, it’s worth taking a few moments to examine which popular theories Dye rejects as insufficient to explain knee pain. Doing so helps explain what compelled him to develop his analytical framework in the first place.

Dye, a long-practicing orthopedic surgeon, surveys current approaches to handling patellofemoral pain with more than a touch of dismay. What he sees are theories that often lead to “corrective” surgery that is worse than ineffective; it actually harms the patient.

For one, some in his field are obsessed with cartilage to the point that they try to fix damaged tissue through chondroplasties and microfractures. (Note: here my thinking somewhat diverges from his, on the role of bad cartilage in contributing to knee pain, but that’s a long digression -- in any event, I think he’s right that much surgery is unnecessary).

As Dye observes, the level of pain a patient experiences doesn’t always correlate well with the degree of chondromalacia in the knee. You may have advanced chondromalacia and no symptoms, or articular cartilage that appears normal that’s associated with a very painful joint (all true, but I think the total picture is a bit more complex).

Dye also rejects the “malalignment” school of thinking (what I have often disparaged as “structuralism”), which commonly blames knee pain on an improperly tracking kneecap. He gives several reasons why this analysis doesn’t make sense.

If the presence of observable factors of malalignment is so important ... why does one find patients with bilaterally radiographically determined patellofemoral malalignment [that is, mistracking in both knees as indicated by X-ray], with only unilateral symptoms [that is, symptoms in only one knee]?

Or there’s this to ponder:

Why do more than 90% of patients with anterior knee pain who have a diagnosis of malalignment as the cause have a successful response to conservative therapy, even though there has been no documentation of long-term restoration or correction of the supposed causative underlying indicators of malalignment.

Finally, he points out:

The malalignment theory also does not explain the variability of patellofemoral symptoms in the same patient at different times, including the presence of sharp pain on occasion and then dull aching pain on another.

He does recognize that “some patients have clinically significant malalignment” that responds well to corrective treatments, such as a lateral release. “However,” he goes on to caution, “in my experience, the numbers of these patients are relatively few.”

Finding the blame-the-cartilage and blame-the-malalignment frameworks for understanding and dealing with knee pain wanting, he comes up with “envelope of function.” But what does this perspective imply, in practical terms, if you’re trying to fix a couple of bad knees?

Here are what I consider two interesting implications:

“Envelope of function” is kind of a big tent idea. That is, you can interpret it as being somewhat agnostic about the origin of knee pain. What matters, a believer could argue, is the fact that you have a certain degree of knee pain and, given that, what’s the best way to heal?

For example, I thought my pain stemmed from cartilage problems. Maybe I was right. Maybe I was wrong. Arguably, an “envelope of function” approach works in either case because, primarily, your concern is staying within the range of loading that your joint can tolerate.

Obviously, this concept wouldn’t make sense for a patient who has an important, identifiable contributor to knee pain that must be dealt with before healing can occur -- the equivalent of an iron spike sticking out of the joint that must be removed first. But I don’t think that describes the vast majority of patients who have chronic knee pain.

An “envelope of function” approach suggests it’s absolutely critical to determine that range of optimal loading for your bad knee. The best place to do this, in my opinion: at a doctor’s or physical therapist’s office, using machines/devices that can quantify exactly how much load your knee can safely tolerate.

Yet very few medical professionals attempt to do this. This is one reason I think we’re still in the Dark Ages on treating chronic knee pain. The American military can fire a cruise missile down a chimney 1,000 miles away, but the U.S. medical establishment can’t (or has no desire to, more significantly) measure how much force an individual can safely put on a bad knee joint, over the course of a 24-hour day.

Now, what does Dye himself recommend for patellofemoral pain patients, besides a “scrupulous adherence to load restriction within the patient’s reduced envelope of function”?

An anti-inflammatory program.

He appears to favor icing and medication, and approvingly cites a regimen of icing 15 to 20 minutes, two or three times daily.

Indeed, runaway chronic inflammation -- the undesirable kind -- is a problem among those who have constant knee pain. I’m a little leery of his solution though, as I usually associate icing and medication with people who use both to keep doing unhealthy things (such as running when their knees aren’t strong enough). Also, icing and medication interfere with the signaling you get from your knees that’s often telling you, “Stop doing that!” (sitting, standing, whatever)

Still, anti-inflammatories may be a good idea, if used smartly.

He also supports painless (his emphasis) muscle strengthening, stretching and patellofemoral taping.

My own opinion (as I’ve made clear on this blog): stretching isn’t of much use but if it feels good why not?, muscle strengthening should be put on the back burner completely in favor of “joint strengthening”, and as for taping -- sometimes it can offer relief, so why not try it as an interim measure?

“A period of 6 to 9 months of conservative therapy often is required” to improve an ailing joint, Dye informs us soberly, then warns: “The first pain-free day does not mean that the envelope of function has been fully restored but that healing is occurring.”

Getting to the right healing program isn’t easy, as Dye observes. “It is not unlike trying to find the numbers to a combination lock.” True, so true. However, when you succeed in finding the right sequence that springs that stubborn lock, and get squarely on the long-term path to getting better, it’s really a great feeling.

Why You Need to Know About the “Envelope of Function”

Ah, where to begin?

This will be a two-parter because there’s so much to say.

First, anyone who’s read Saving My Knees knows that I openly acknowledge a huge debt to Doug Kelsey, a very smart physical therapist who heads a clinic in Austin. His writing showed me (1) Bad knees can get better; don’t listen to any doctor who says they can’t (2) The right kind of exercise to rehab a bad knee joint is low load, high repetition.

At some later point, I found Paul Ingraham on the Internet. Ingraham, a former massage therapist in Vancouver, wrote long essays that were sharply reasoned and easy to read, often debunking things that 99 percent of his colleagues believe. He showed me that (1) stretching probably isn’t of much use at all (2) physical therapy’s obsession with “crookedness” has led the profession down a questionable path.

So I had managed to stumble across, quite fortuitously, two therapists whose insights possessed great appeal. All that was missing, really, was a doctor to provide a more formal framework for the right way to understand chronic knee pain.

Enter Scott F. Dye.

I’ve been aware of some of his ideas (such as the “envelope of function” and the importance of tissue homeostasis) for a while, but only recently (because of a reader comment) was prompted to look into them more deeply. And I’m glad I did.

The idea of the “envelope of function” is the cornerstone of his thinking on nagging knee pain. He describes it as “the range of painless loading compatible with tissue homeostasis of a joint without causing structural or physiologic injury.”

In other words, there’s an optimal range of load-bearing activity for your bad knee, within which healing can occur. If you drift outside of this range, or envelope -- either by pushing your knee too hard or not placing any demands on it at all, which leads to its own problems -- you’ll thwart that healing process.

Simple, and spot on, from my own experience.

Dye identifies a problem many of us face after hurting our knees:

The envelope of function, or the safe range of painless loading, frequently diminishes after an episode of injury to the level where many activities of daily living that previously were well tolerated become symptomatic, leading to the prolongation of symptoms.

Huge.

This is exactly the issue for so many people, but they don’t modify their behavior in response. The above quote brings to mind a wince-inducing comment I recall reading once from someone who couldn’t climb stairs without pain. His solution? “I just pop a couple of Advil.”

Umm, right.

And people like that wonder why their knees never heal?

So if you want to fix your bad knees, it’s important to determine your own “envelope of function” and faithfully stay within it, healing slowly and steadily. Of course that does raise a bunch of interesting questions about the therapeutic implications of an “envelope of function” approach to beating knee pain.

Next week I’ll look at some of those.