Don’t Get Sidelined: Understanding the ACL

The anterior cruciate ligament (ACL) is one of four major ligaments that provide stability to the knee joint. Damage to these ligaments can require surgery and a lengthy rehabilitation. Preventative measures and programs can be taken early to reduce the risk of serious injury.

The ACL is the ligament that crosses the center of the knee and helps control excessive motion of the knee joint by keeping the lower leg from sliding too far forward. Of the four major ligaments of the knee, ACL injuries are most common. The majority of ACL reconstructions each year are performed on athletes under age 25 and is most common in female athletes.

ACL injuries are common in sports that involve sudden changes of direction, like basketball, tennis, soccer and football. Most are non-contact injuries that occur during sudden twisting motion or when landing from a jump. Factors contributing to ACL injuries include ground hardness, and grass and cleat type.


Athletes may reduce their risk of ACL injury by performing training drills requiring balance, power, core strengthening and agility. Adding plyometric exercises, such as jumping and balance drills, helps improve neuromuscular conditioning and muscular reactions and ultimately shows a decrease in the risk of ACL injury. Many coaches, athletic trainers and team physicians now routinely recommend an ACL conditioning program.

Treatment Procedure

When knee surgery is necessary, ACL reconstruction is performed by replacing the torn ACL with a ligamentous graft. With arthroscopic assisted surgery, a small telescope is inserted into the knee. With a tiny camera connected to the telescope and video monitor, the surgeon checks the ligaments and cartilage structures of the knee.

Leaving a torn ACL untreated can lead to cartilage damage and early arthritis. ACL reconstruction may be recommended for a knee that gives way or feels unstable during daily activities, causes general knee pain, inability to continue playing sports or other activities.


After surgery, the phased rehabilitation process begins. Patients begin working with a physical therapist to regain motion, strength and pain control. Eventually, exercises are performed to adapt to quick shifts in motion, position and force. In the latter phases, rehabilitation mirrors what conditioning programs teach prior to injury. Exercises can range from jumping rope to strengthening muscles.

Most importantly, rehabilitation will assist the patient in learning to recognize the limitations of their bodies, which helps to avoid reoccurrence. The post-operative rehabilitation time is approximately three months with a planned return to sports in six to twelve months.

Only your surgeon can help you decide what treatment is best for you. Talk to J. Lex Kenerly, M.D., Orthopaedic Surgeon, and the staff at the Bone & Joint institute of south georgia if you have questions about preventing ACL tears or ACL replacement surgery in general.

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