Some of the most important players on NFL teams are those that might not necessarily start the season on the field.

Injuries to the MCL (medial collateral ligament) can cause knee pain and instability. Learn about MCL sprains and tears, surgical and nonsurgical treatments.

ACL tears can be accompanied by injuries to other tissues in the knee, including the meniscus, cartilage, and the other knee ligaments (MCL, PCL, LCL). The most common injury associated with an ACL ...