Anterior Cruciate Ligament (ACL) Tear
An anterior cruciate ligament (ACL) sprain is a tear of one of the four major ligaments of the knee. The ACL is a ropelike structure in the center of the knee that helps maintain the normal relationship of the femur (thigh bone) and the tibia (leg bone). When torn, the ACL does not heal and the knee can be unstable (shifts or gives way) during sports that require pivoting, changing direction (cutting), jumping, or landing. About half the people who tear their ACL also tear their meniscus in their knee.
The diagnosis of an ACL tear is usually made on physical examination but MRI can be helpful, especially when the patient is too swollen or guarded to allow a thorough examination. The MRI is also needed to diagnose any associated meniscal or cartilage damage.
The ACL will not heal on its own but, most people can return to normal daily activities after an appropriate rehabilitation program. Despite this return of normal daily function, ACL deficient knees are at risk for progressive meniscus and cartilage damage from abnormal knee mechanics. For those who want to return to sports that require pivoting, cutting, and jumping and landing, surgery is usually required. Surgery also is recommended for ACL injuries combined with other ligament, meniscus, or cartilage injuries.
Initial treatment is focused on returning the knee back to its pre-injury status by reducing the pain and swelling and restoring the range of motion, strength, and gait. Walking with crutches until you walk without a limp is often recommended. Range-of-motion, stretching, and strengthening exercises may be carried out at home, although a referral to a physical therapist or athletic trainer is often recommended. If other ligaments are injured along with the ACL, Dr. Steven Chudik may recommend a brace to help hold the knee stable.
For those patients who do not perform sports that require frequent pivoting, cutting, jumping and landing, surgery is not required and rehabilitation is recommended. Individuals usually can continue to jog, cycle, lift weights and swim without ACL surgery; however, they are at a greater risk for progressive damage to their meniscus and cartilage from abnormal knee mechanics. Rehabilitation of ACL tears usually concentrates on reducing knee swelling, regaining knee range of motion, regaining muscle control and strength, functional training and education to avoid sports/activities that require pivoting, cutting, changing direction, jumping and landing.