Knee pain

Tim McNamara said:

Another issue might be crank length. In 2003, I decided to try 180 mm
cranks because I have long legs (91 cm inseam). I rode them about
1000 miles/1600 km and developed pain in my left knee on the medial
side. It was a stabbing sort of pain on extension of my leg. X-rays
showed nothing disceribly amiss, so it's probably a soft tissue
problem. Going back to 175 mm cranks alleviated the pain when
cycling, but if I sit cross-legged for even a couple of minutes my
knee hurts like heck when I try to walk; zazen is out of the question.
No diagnosis thus far. Anyway, in a rambling and roundabout manner, I
am suggesting that you not only consider narrower cranks but shorter
ones as well. If you have short legs and are riding 175 mm cranks,
that might be a contributor.

I've often wondered about this. Considering how small 5mm is in relation to
your body, and to the variance between bodies, it doesn't seem like it could
matter. So if you've been riding 175mm cranks for many years, then switch to
180mm, you're merely hitting a new wear point on your knee -- whereas if you'd
started out with 180mm, or even 190mm, you'd be fine. ???

That aside, most knee problems are caused by two things -- pivoting an office
chair, and getting in and out of cars. The more overweight you are, the more
the latter is a problem. But the former can afflict anyone. So if you work in
an office, and you're constantly pivoting and pushing your chair around -- look
there, and not at your bicycle cranks.

Matt O.

Matt O'Toole said:

That aside, most knee problems are caused by two things -- pivoting an office
chair, and getting in and out of cars. The more overweight you are, the more
the latter is a problem. But the former can afflict anyone. So if you work in
an office, and you're constantly pivoting and pushing your chair around -- look
there, and not at your bicycle cranks.

Fascinating. Do you have a source for that? A quick search on PubMed
did not turn up anything.

Tim McNamara said:

IME this works very well with Achilles pain as well. I developed
tendinitis in my Achilles on a 600km brevet in 2003, and moving my cleats
backwards about 5mm really helped.

Thanks, doc, I think I'll take your advice. I've been having pain in my
right achilles tendon area. Only change is new shoes. I _thought_ I got
the cleats in the same place. I will try moving them back a bit. The
heel on the new shoes is shaped differently, and my foot may be a bit
futher back WRT the sole.

--

David L. Johnson

__o | "A foolish consistency is the hobgoblin of little minds, adored
_`\(,_ | by little statesmen and philosophers and divines." --Ralph Waldo
(_)/ (_) | Emerson

Jim Smith said:

Matt O'Toole said:

That aside, most knee problems are caused by two things -- pivoting
an office chair, and getting in and out of cars. The more
overweight you are, the more the latter is a problem. But the
former can afflict anyone. So if you work in an office, and you're
constantly pivoting and pushing your chair around -- look there, and
not at your bicycle cranks.

Fascinating. Do you have a source for that? A quick search on PubMed
did not turn up anything.

A friend/neighbor who does research into this kind of thing for health insurance
companies and the government. MD/actuary, pretty smart guy, with his finger on
the pulse of what's happening out there. Gets called to Washington a lot to
present papers and stuff.

Matt O.

Matt O'Toole said:

Tim McNamara said:

Another issue might be crank length. In 2003, I decided to try 180
mm cranks because I have long legs (91 cm inseam). I rode them
about 1000 miles/1600 km and developed pain in my left knee on the
medial side. It was a stabbing sort of pain on extension of my
leg. X-rays showed nothing disceribly amiss, so it's probably a
soft tissue problem. Going back to 175 mm cranks alleviated the
pain when cycling, but if I sit cross-legged for even a couple of
minutes my knee hurts like heck when I try to walk; zazen is out of
the question. No diagnosis thus far. Anyway, in a rambling and
roundabout manner, I am suggesting that you not only consider
narrower cranks but shorter ones as well. If you have short legs
and are riding 175 mm cranks, that might be a contributor.

I've often wondered about this. Considering how small 5mm is in
relation to your body, and to the variance between bodies, it
doesn't seem like it could matter.

Given that Andy Pruitt's treatment of such problem often includes
saddle adjustments of 5 mm or less, it seems that it may be possible
that such small incremental difference could have a negative effect.
It seems like such a small amount, 5 mm vs 910 mm! Yet in my case at
least, cause and effect seemed pretty clear.

Quoted message said:

So if you've been riding 175mm cranks for many years, then switch to
180mm, you're merely hitting a new wear point on your knee --
whereas if you'd started out with 180mm, or even 190mm, you'd be
fine. ???

Well, the problem only started after changing the cranks and went
away- at least while riding- after going back to the 175s. The
improvement was immediate. This was theonly change made to a bike I'd
been riding for years. Presumably that "new wear point" was
problematic. I don't think this is a cartilege problem, as the X-rays
showed no indication of thinning. I'm thinking that a tendon or
ligament got injured, or perhaps there is a medial plica problem.

Quoted message said:

That aside, most knee problems are caused by two things -- pivoting
an office chair, and getting in and out of cars. The more
overweight you are, the more the latter is a problem. But the
former can afflict anyone. So if you work in an office, and you're
constantly pivoting and pushing your chair around -- look there, and
not at your bicycle cranks.

My job is such that I don't sit on office chairs more than a few times
a week. At 6'4" my 215 lbs is above ideal weight, although I carry a
lot of muslce mass, and I doubt that's the problem. Since I've been
an avid cyclist for over 30 years, the sorts of common knee problems
that result from weak muscles are unlikely- such as the office chair
problem or gtting our of cars.

"David L. Johnson" <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

Tim McNamara said:

IME this works very well with Achilles pain as well. I developed
tendinitis in my Achilles on a 600km brevet in 2003, and moving my cleats
backwards about 5mm really helped.

Thanks, doc, I think I'll take your advice. I've been having pain in my
right achilles tendon area. Only change is new shoes. I _thought_ I got
the cleats in the same place. I will try moving them back a bit. The
heel on the new shoes is shaped differently, and my foot may be a bit
futher back WRT the sole.

David: Tim has a good idea, but you might also want to examine your
new shoes. There is some good information on www.AchillesTendon.com
which helped me a lot with my Achilles tendon injuries. Their shoe
discussion has info on pronation, arch support, heel support,
cushioning, etc., some of which might apply to your new shoes. Good
luck.