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- Wed Jul 14, 2004 11:13 pm
In March of 2003 i dislocated my knee. I've been through all the physical therapy and I've worn all the braces and such. Now I'm done with all of that -- no more braces and no more PT. My (left) knee will still hurt sometimes -- it is worst when I try to drive stick. Anyway, my concern is with biking. I would like to go on lesiurely, 20-30 mile bike rides from time to time. I've only dared go on two or three rides since i dislocated the knee. When I bike, I can feel my kneecap popping in and out of the socket, which is either uncomfortable or a little painful. Most of the pain, however, does not occur during the bikeride -- it happens afterwards. In fact, the knee continues to be sensitive for one or two days after the ride. So my questions is: am i helping or hurting? One side of the argument might be that I'm helping strengthen the knee, while on the other hand I might just be prolonging the injury. Can my knee handle bike rides?
| Dr. A. Saif
- Thu Oct 28, 2004 4:40 pm
Dear PT Hunkie,
There are some reasons why someone would dislocate a patella and some consequences of the dislocation itself that one needs to understand. The legs in a normal adult are as you will see in your own, angled outwards slightly at the knee. The knee cap, sits in a groove at the end of the femur (the femoral groove) and slides up and down within this groove. Because of the angle of the knee, the knee cap has a tendency to move toward the outside. This migration is prevented partly by the depth of the femoral groove, the fact that the outer edge of the groove is higher, and the fact that you have balancing muscles on the inner side of the knee called the Vastus Medialis Obliquus (VMO).
The reasons to dislocate are thus an increased outward angle of the knee (women have a naturally increased angle and are thus more vulnerable), a shallow femoral groove, or weakened VMOs. the consequences of the the dislocation are injury to the patello femoral joint, and to the VMO itself.
By the splinatge and bracing you had so far, you will allow the damage to the muscle to recover, although it will be very weak initially. The damage to the patellofemoral joint recovers very poorly. The latter will thus continue to give you pain for some time, particularly when you kneel, go up stairs, or get up from a sitting position. The weakness of your Medialis must be overcome first, to reduce the impact of this.
Cycling is normally good exercise. Cycling, as you seem to be doing, and the apparent subluxation that is occuring will harm your knee, by increasing the damage to your PFJ. You must improve the function of your medialis sufficiently first. Try this exercise religiously. Lying down on your back, extend knee, turn your foot outards, and raise it up and down. Do this for 10 minutes twice a day, increasing gradually. Note that this exercise does not bend your knee or increase the load through your knee.
It may be an idea, when you get back to cycling to raise the seat of your bike to reduce the flexion your knee goes through. If this still leads to no improvement...it will be worth seeing a specialist again.