I can't exactly drive across the ocean instead of flying
March 10, 2010 5:57 PM   Subscribe

What to do about knee pain as a result of flying?

I noticed that over the last 3 years I get knee pain after flying. It doesn't start hurting until a few days after I fly, and lasts for a month or two. It has happened to both knees (but only one at a time so far), and hurts in different places every time - behind the knees, right under the kneecap, on the side. The majority of the pain is usually in the morning. There is no visible swelling. I do walk around at least every 2 hours on flights and stretch, so the pain is not due to sitting for a long time. I am generally healthy and work out regularly.

I went to the doctor for it once, and he found nothing after 3 hours of x-rays. Due to crappy insurance I would rather not get an MRI. I know you are not my doctor, etc etc, but if anyone has any experience or suggestions, I'd like to hear them.

1. How can I prevent it? I have several trips coming up. Would taking glucosamine/MSM help? Wrapping my knees during the flight?
2. Is it still safe to run on the knee later on in the day when it hurts a lot less, or would that injure it more? (swimming actually hurts like hell, compared to running)
3. Any other suggestions?
posted by KateHasQuestions to Health & Fitness (7 answers total) 2 users marked this as a favorite
 
I'm a fellow mystery knee-pain sufferer. I first noticed my knee pain 12 years ago whilst on a trans-pacific flight. I thought it was flight-related for a while until it used to occur at random when I had not flown for a long time.

Depending on how often you catch planes, are you sure the pain is not just co-incidental to flying?

There are lots of causes of knee pain. I have had x-rays done and there is nothing wrong that will show on an x-ray. The pain is not caused by infection, inflammation, fluid or mineral deficiency. It is not caused by inactivity, over-activity, cold or changes in air pressure although I have blamed all these things in the past.

It turns out my knee pain comes from weakness and instability in my ankles which in turn is related to genetic factors and weakness in the little muscles in the arches of my feet. I have exercises to build strength in my feet and legs generally and they help to reduce the frequency and intensity of the knee pain.
posted by evil_esto at 6:36 PM on March 10, 2010 [1 favorite]


Unfortunately mild chronic pain like yours is often very difficult to diagnose.

The best thing you can do is to take detailed, consistent notes about how you feel, every single day. Twice a day, if possible. Write down how you feel. Grade your pain (1 to 10). Describe exactly where the pain is -- using precise terminology (anterior, posterior, medial etc). Describe what postures, motions and activities cause the most pain. Note your activities on that day. Note what you ate, drank. Note the weather.

Try to do this all in a spreadsheet, in a format that can easily be sorted, graded, categorized, etc. Once you have 6 months of data, then you can more objectively analyze for trends and causes, rather than relying on anecdotal memory which is usually wrong.
posted by randomstriker at 7:02 PM on March 10, 2010


Response by poster: Pretty sure it's flight related - I fly about twice a year (have flown in all seasons), and if I fly more often within a month or two, the pain intensifies. It never hurts if I didn't fly very recently, and it never hurt until I started traveling by plane a few years ago.

Would glucosamine help? If I try taking it and it doesn't help, would it hurt?
posted by KateHasQuestions at 7:22 PM on March 10, 2010


It would be interesting to see if this is related to flight, or if it is related to incidental things that just happen to be happening on days that you fly.

How long are you in the leg? Do you need to pivot your leg to avoid crushing your knees on the seat in front? This can cause pain on the side of the knee.

How about seat height? If you're even a little bit loose-ligamented, plus taller than the theoretical human the seat was designed for, and are sitting straight up, you'll get pain above the kneecap.

Do you wear a specific pair of shoes to travel that you don't wear at other times? My friend had a similar problem to yours, and the root cause was trotting through terminals in her TSA-friendly-but-overpronation-permissive "flyin' shoes".
posted by Sallyfur at 10:40 PM on March 10, 2010 [1 favorite]


I took Glucosamine for about 6 months with no effect I could tell. It might help if your problem is arthritis. There can be side-effects.
posted by evil_esto at 12:18 AM on March 11, 2010


If you'll pardon me for saying so, and I do intend it in the least detached and clinical way possible, you are a very interesting case, KateHasQuestions.

I was surprised that no one mentioned, in response to your question about compulsively cracking almost every joint in your body, that the cracking noise is due to gas (nitrogen supposedly) bubbles that form in the fluid-filled sacs (bursae) surrounding your joints in response to the sudden drop in pressure which is produced when you pull on your fingers, for example.

I think all that cracking means you have an unusually large amount of gas dissolved in the synovial fluid which fills your bursae, and that's what's ultimately causing the pain in your knees after you fly.

When you fly from an airport at sea level, say, cabin pressure is supposed to drop smoothly and not too rapidly to the equivalent of about a maximum elevation of 7000 feet.

I believe the unusually large amount of gas dissolved in your joints has a tendency to come out of solution as the pressure drops, and blows up your joints like little balloons.

Now since the pain you describe is much greater when you swim than when you run, it is probably not arthritis, but bursitis.

I would say such bursitis is produced in your knees by the many tendons and ligaments of the knee which surround the bursa on all sides rubbing strongly against the outside surface of the little balloon in its blown up state. It probably takes awhile for the gas to be reabsorbed, and during all that time, the tendons are rubbing on the bursa and irritating or possibly even eroding it. Then three days later the inflammation and pain set in.

Why only the knees? I don't know. The knees do seem to have the most complicated and constraining connective tissue of any joint. Have you injured or damaged your knees in the past? Or did you have strep throat which led to 'growing pains' in your knees?

Even if all this is true, it doesn't answer the question of why you would have more gas dissolved in your synovial fluid than other people do.

More on that tomorrow maybe, if I haven't invaded your privacy too far already.
posted by jamjam at 2:06 AM on March 11, 2010 [2 favorites]


awesome ans jamjam, (or should I call you Gregory?)
I was going to pop in something about the synovial fluid.

I'm guessing a good physio could massage pre- and post flight to try to disperse this build up. I would also add that it's likely at some time in the past you had some viral infection causing a cytokine storm which has left a bit of detritus in your knee joints more so than other joints which is why they are affected.
Glucosamine can't hurt bt I don't see it making a big impact. Prophylactic anti-inflammatories on day 2 post flight, maintained for a week could give you good symptom relief.
Kairab my OH who is the pain specialist says
(I'm going to be really lazy and just cut and paste his reponse to another question, lazy paraphrase is Paracetomol and Brufen in the proper dosages gives good pain relief)
""(2) It may be that your pain can be reduced by adding nonsteroidal anlagesics to the acetaminophen. This is an emerging field of study - conventional wisdom used to state that NSAIDs and acetaminophen act on the same biological receptor systems and combining them therefore makes little sense. As our knowledge of the cyclo-oxygenase (COX) enzyme subtypes increases, this view is now beginning to shift, and there are some studies suggesting that combining the two drug types (NSAIDs act on COX-1 and/or COX-2, while acetaminophen acts on COX-3) can achieve approximately 35% better analgesia (or reduced opioid requirement). I must emphasise that you should be aware of the equally horrendous potential side-effects of NSAIDs: Kidney failure (if you are dehydrated or have poorly functioning kidneys already), stomach ulceration and/or haemorrhage (bleeding), worsening of asthma in asthmatics, and heart failure in those with an already straining heart. Also, a proportion of people are allergic to aspirin and related NSAIDs, whereas true allergy to acetaminophen is quite rare.

(3) I feel you are getting very focussed on the here & now of your pain and on pharmaceuticals. It would be much more productive to ascertain what is causing your pain, and how certain the diagnosis is: Knowing this could both inform more efficacious prescribing as well as (possibly) open up other (non-pharmaceutical) approaches to alleviating the pain. Don't forget, BTW, that physical pain is (usually) nature's way of telling you that there is something going wrong within you. This needs to be excluded first, before it makes sense to try and suppress the pain message or tune down your receiver (brain).

(4) Are there other stressors that may operate to increase your pain perception, such as psychological factors independent of but coexisting with, your pain problem (family, job, etc...?). Are you lacking - or not allowing yourself to access - emotional supports (friends, partners, family)? If you seriously think about it, is there possibly a (psychological) "secondary gain" associated with being seen by others as having an unsolved pain problem? I appreciate that you are crying out for help over the internet, and this is not necessarily a dumb way of going about it, but are there not suitable sources of aid closer to you on the ground? For the reasons outlined above, for persistent pains refractory to straightforward treatments this may reasonably extend beyond doctors, nurses and pharmacists to include counsellors, psychologists and psychotherapists.


I really wish I could favorite jamjam more than once!
posted by Wilder at 3:13 AM on March 11, 2010


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