The ligamentous injuries that occur during grappling and BJJ movements are usually the result of overeager novices or simply mistakes during the heat of competition. Sprains are injuries to the ligaments, which are the connective tissues that attach bone to bone, like the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL). Since ligaments have very poor elastic properties, any damage will usually be partial tearing or complete rupture of the ligament. These types of injuries are usually accompanied by a popping sensation followed by immediate pain — you will know when you tear a ligament simply by the sound and subsequent pain.
The ACL is a ligament that prevents your leg from shifting forward on the thigh (it prevents hyperextension of the knee). The knee bar specifi cally puts strain on the ACL, and if a competitor does not tap out there is a strong chance for damaging the ACL. Another common mechanism for ACL injury is getting your knee hyper extended from standing and pivoting while resisting a single leg shoot.
One of the fi rst symptoms of an ACL rupture is a loud pop followed by pain and swelling in the knee joint. The knee will feel very unstable, and you will have diffi culty walking. A competent sports physician should be able to diagnose a complete ACL tear, but an MRI is necessary to determine whether it is a grade I, II, or III sprain. A grade I sprain involves pain with minimal damage to the ligament. Grade II sprains involve more ligament damage along with mild laxity (looseness) of the knee joint. A Grade III sprain involves complete tearing of the ligament with instability at the knee.
If you sustain a complete tear and you desire to continue to train and compete, you will eventually need to undergo an ACL repair procedure. Since the ACL does not heal itself, the surgery involves reconstruction using tendons or ligaments from another part of your leg or a cadaver. The good news is that with the appropriate physical therapy and rehab your knee can be as good as new after the surgery.
The MCL is located on the inside of your knee and holds the thigh and leg together. This ligament is often injured by a hit to the outside of the knee accompanied by twisting motions. If you sprain or tear your MCL, you will feel pain on the inside of the knee. There may be some swelling, and your knee may feel unstable. Fortunately, most complete MCL tears rarely need surgery and recover nicely after appropriate rest and rehab.