Chronic Knee Pain: The Great Impostor (and Mystifier)

In the comments section, TriAgain (a regular reader) recently asked me an interesting question. Do I think I might have had “complex regional pain syndrome” when I was struggling with a pair of knees that often burned?

“Complex regional pain syndrome” ... it faintly rang a bell. My curiosity piqued, I looked up this definition:

Complex regional pain syndrome (CRPS) is a chronic pain condition most often affecting one of the limbs (arms, legs, hands, or feet), usually after an injury or trauma to that limb.  CRPS is believed to be caused by damage to, or malfunction of, the peripheral and central nervous systems.

Yeah, but what are the symptoms, I wondered. So I read on:

The key symptom is prolonged pain that may be constant and, in some people, extremely uncomfortable or severe. The pain may feel like a burning or “pins and needles” sensation ... The pain may spread to include the entire arm or leg, even though the precipitating injury might have been only to a finger or toe. Pain can sometimes even travel to the opposite extremity.

Okay, with you so far. Then I hit this section:

People with CRPS also experience constant or intermittent changes in temperature, skin color, and swelling of the affected limb ... The skin on the affected limb may change color, becoming blotchy, blue, purple, pale, or red.

Other common features of CRPS include:
* changes in skin texture on the affected area; it may appear shiny and thin
* abnormal sweating pattern in the affected area or surrounding areas
* changes in nail and hair growth patterns
* stiffness in affected joints
* problems coordinating muscle movement, with decreased ability to move the affected body part, and
* abnormal movement in the affected limb, most often fixed abnormal posture (called dystonia) but also tremors in or jerking of the affected limb.

Uh, nope. Pretty sure I didn’t have that.

So why did I describe TriAgain’s question as “interesting” if this syndrome appears to have no relevance to my former condition? Because I know exactly what’s he’s going through.

When I had knee pain all the time, I Google’d everything under the sun, trying to figure out what was going on with me. I skimmed articles about conditions with long Swedish names that contained funny-looking vowels. I even had a blood test for rheumatoid arthritis (which I passed with flying colors), as a I recount in my book.

Why so much confusion about a pair of damaged joints?

Here’s my best guess as to what happens with a lot of chronic knee pain patients (note: of course some may have complex regional pain syndrome, or rheumatoid arthritis -- or some other condition -- as their primary problem; I don’t mean to discount that possibility).

You start out by having simple knee pain, but as time goes on -- and as your body enters a long-term inflammatory state -- you notice other problems that seem more systemic, or not related to your original localized pain, and you discover your knees seem sensitive to non-physical stressors, such as emotional stress or depression.

Okay, I’m kind of spitballing here, making a guess based on my own experience and personal accounts I’ve read by others. But it seems this progression, from basic knee pain to something more elusive and insidious, is not uncommon.

Now, what if this is indeed true? What if many of us suffer from bad knees + something systemic that is weird and hard to figure out? (note: again, this assumes that the systemic stuff isn’t your main problem -- e.g., you don’t have a disease like rheumatoid arthritis). What to do?

Well, I’m not sure what you can do about the systemic issues or even what they are exactly. However, fixing the damaged knees -- that (once again) I think requires a long, slow program of gradually increasing load on the joints.

My best guess is that, if you fix the bad knees, the weird systemic stuff (the nettlesome “ghost in the machine”) will go away, at least in most cases. It did for me anyway!