Basketball is now in full swing and sadly anterior cruciate ligament (ACL) injuries are on the rise.  More than 250,000 ACL injuries occur each year in the United States, with ACL reconstruction becoming one of the most common surgeries performed by orthopedic surgeons.

The ACL is a ligament (connects the thigh bone to the shin bone) providing stability to the knee.  It prevents the tibia from shifting out from underneath the femur.  It is the most extensively studied ligament in the body.  Loss of the ACL generally results in functional disability, particularly in jumping, cutting and deceleration activities.  Occasionally, athletes can accommodate for this loss of function while most require surgical reconstruction of the ligament to provide stability and to protect their knee cartilage from further injury.

Who is at risk – anyone participating in an activity, sports or otherwise, that places their knee under stress or strain is at risk of injuring their ACL.  Statistics have shown that females are at a greater risk of ACL ligament injuries than males, especially those participating in a sport that requires jumping or sudden change of direction.

ACL injury usually occurs while changing direction or landing from a jump.  The athlete will commonly feel a “shift” and will hear or feel a “pop”.  Swelling is usually noted within hours, and the athlete will rarely be able to continue to participate.

Diagnosis of an ACL tear is usually clinical.  Physical exam by a trained professional is very accurate.  Occasionally, further testing such as magnetic resonance imaging (MRI) is needed.  Once an athlete has torn their anterior cruciate ligament, it will not heal itself.  Treatment at that point consists of conservative (no surgery) vs. operative reconstruction.  Athletes that try to resume their normal sports activities with an ACL insufficient knee, even when braced, are at high risk of further damage to the cartilage in the knee.

Reconstruction of the anterior cruciate ligament can be performed in a number of ways.  It is usually an outpatient procedure with physical therapy starting soon after the procedure.  Most surgeons will arthroscope the knee at the time of ACL reconstruction and address any other concomitant injuries at the same time as the reconstruction. 

Once an athlete has had an ACL reconstruction, rehabilitation is extremely important to regain motion, strength and stability of their knee.  Most athletes are able to return to their full sports activities 6-12 months after reconstruction.

There are ACL prevention programs that are designed to lower an athletes’ risk of ACL injuries.  There are several different programs, most of which have been shown to be effective in reducing the risk of ACL tears.  Most of these programs are designed to improve dynamic muscle function around the knee to decrease the strain on the ACL during activities.  These programs are designed primarily to increase hamstring strength, increase endurance of the muscles across the knee and increase knee stiffness during landing and pivoting.

Red flags that should alert the parent or coach that an athlete should seek medical attention include:

     1.     A history of feeling a pop of shifting episode in the knee
     2.     Pain which limits activity
     3.     Loss of knee motion
     4.     Swelling
     5.     A feeling of instability