Meniscal Tears
Tears of the meniscus are very common knee causes of knee pain. The menisci are "C" shaped pieces of cartilage on the inner and outer portions (medial and lateral) of each knee. They can be thought of as shock absorbers that provide padding between the femur and the tibia. They help increase the congruity between the bones to distribute forces more evenly. Contact pressures increase significantly in the knee following loss of function of a meniscus.
In younger people, tears typically are the result of a traumatic injury. As you get older (over 40), degenerative tears become more likely. Each meniscus has a poor blood supply (in adults, only the peripheral 1/3 is vascularized), so they have poor healing potential. Tears can be isolated or associated with other injuries (e.g. ACL tears).
Symptoms of a torn meniscus typically include sharp/localized pain especially with twisting movements of the knee. The knee also usually swells following the injury. There may be painful popping (Note: painless "popping" in knees is NORMAL) and/or locking if the torn piece of meniscus flips into a position where it blocks knee motion.
Most menisci won’t heal spontaneously on their own, but if they do symptoms should diminish over 1-2 months. If they persist over 6-8 wks, then it likely won’t heal. Surgery 30 years ago entailed removing the entire meniscus. As these patients have come back with severe arthritis in that compartment, we’ve started just arthroscopically removing only the torn portions. Some menisci may be amenable to an attempt to repair (depends on a lot of factor . . . leave it up to your doc), but if repair is tried the patient must realize that it could fail which would mean another surgery down the road to remove the torn piece. At the latest ortho national academy meeting, it looks like the trend is to be more aggressive for repair in younger patients to try and save the meniscus since our other bailouts (e.g. meniscal transplants) aren’t working out that great long term (the transplants are failing 5-7 years out).
Recovery/rehab depends on the procedure performed, but in general non-impact exercises are preferred to limit the progressive wear and tear on the knees.
