An MCL injury is
a tear in one of the ligaments in the knee.
More to Know
The MCL is one of the four main ligaments in the knee joint.
It is located on the inner side of the knee — the side that is closest to the
other knee. The MCL works together with the lateral collateral ligament (LCL),
which is in the same location on the outside of the knee. These two ligaments help
prevent the knee joint from overextending from side to side.
MCL injuries are common, especially among kids and teens who play contact sports
like football. The injury happens when the outside of the knee is struck, causing
it to unnaturally bend inward toward the other knee. MCL tears usually cause swelling
and pain within the first 24 hours of injury. If you suspect an MCL injury, stop
all activity, keep the area iced and elevated, avoid putting weight on the knee, and
call your doctor.
Keep in Mind
Although most MCL injuries heal on their own with anywhere from 1 to 6 weeks of
rest, most still require rehabilitation ("rehab") therapy to help regain strength
in the joint.
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