INTRODUCTION​

• The Anterior cruciate ligament (ACL) is one of the major knee ligaments providing stability to the knee

• The primary function of the ACL is to prevent the leg bone from moving forward relative to the thigh bone. 

• Injury to the ACL leads to knee instability and buckling, which is associated with pain, swelling and apprehension

• 80% of ACL tears occur in females

CAUSES

• ACL tears usually occur after noncontact twisting injuries during sports

• They usually occur when the foot is planted on the ground and a bending force is applied to the knee, causing the ACL to tear

SIGNS AND SYMPTOMS

• ACL tears are almost always associated with immediate pain and swelling

• Patients oftentimes hear or feel a “pop” in their knee

• Instability of the knee, such as giving out and buckling, is common after ACL tears

TREATMENT​​

• Treatment of partial thickness ACL tears that are stable on physical exam are usually managed without surgery

• Full or complete ACL tears are usually managed with surgery if patients want to maintain an active lifestyle playing sports and participating in twisting or change of direction

• Patients should have improvement or resolution of their joint swelling and range of motion should be normalized prior to surgery

• Surgery is arthroscopic and consists of using a graft to reconstruct the ACL

• There are numerous graft options, but in general younger patients use their own tissue (autograft) for the graft, while older patients may benefit from a donor graft (allograft)

• Graft options include bone patella bone, hamstring, and quadriceps options. Outcomes are similar with all of these graft options

 

PREVENTION

• Treatment for ACL injuries is effective, but considering the pain, inconvenience, surgery, and lengthy recovery, your best bet is to prevent the ACL injury in the first place

• A growing body of research shows that identifying and targeting weak muscles, such as the hamstrings, can improve strength and coordination and therefore help decrease the likelihood of an ACL injury

• Other risk factors such as increased joint motion can be further assessed and corrected to improve performance.

• Current studies also demonstrate that specific exercises, such as jump routines and learning to land or pivot properly, help athletes prevent ACL injuries, especially in young athletes

• Some experts suggest it may be beneficial to integrate prevention programs during early adolescence, prior to when young athletes develop certain habits that increase the risk of an ACL injury

• Effective methods that help prevent ACL injury include:

• Plyometrics, a type of jumping exercise, used to train and strengthen the leg muscles

• Landing mechanics

• Strength training of hamstrings

• Young athletes would benefit from preseason screening programs that identify ACL injury risk factors in young "high-risk" athletes who would benefit from targeted training programs

• One validated knee injury prevention program I commonly recommend is the Fifa 11 program: https://www.fifamedicalnetwork.com/lessons/prevention-fifa-11/ 

• These prevention programs are more beneficial when athletes start young, before reaching skeletal maturity, so they have time to develop correct habits that decrease the risk of injury

• With appropriate identification, prevention programs can decrease ACL injuries by up to 50%