Anterior Cruciate Ligament Tears

The anterior cruciate ligament is one of the four main ligaments within the knee that connects the femur to the tibia. The ACL and PCL both keep the knee from sliding forwards and backwards. It is one of the most commonly injured ligaments of the knee.1

In contact sports, the impact is usually while the foot is planted and the blow causes the knee to hyperextend. Non-contact sports usually have an ACL tear when they are changing direction quickly, landing from a jump, or stopping suddenly.1 Women are more likely to have an ACL tear than men because of reasons like: anatomy, training, and activity experience. Men also have larger muscle mass in the quadriceps and hamstrings which helps to protect and stabilize the knee better than in women.1

When the tear actually occurs, there will be a loud popping sound. Pain is almost immediate, while swelling occurs within a few hours.2 The knee will feel unstable so walking will be difficult. Straightening the leg will also be difficult, due to the fluid that builds up in the knee.2

Rather than repairing the ligament, the orthopedic surgeon will reconstruct it using a surgery called arthroscopy.2 This is a minimally invasive surgery that leaves little scarring on the knee. For the reconstruction, there are a few techniques that the surgeon and patient discuss before the surgery takes place.1 The “new” ACL can be built using part of the patellar tendon, from part of the hamstring tendon, or from a donor or cadaver knee. Rehabilitation takes between six to nine months before the patient is able to return to full activity.2 A protective knee brace is given to the patient to wear through most of the rehab process to make sure and protect the new ACL from any stress. The brace can and is encouraged to be worn during sporting activities to prevent from reinjury.1

Teaching the muscles around the knee how to react under stress will help to protect and prevent ACL tears.2 Working on agility, balancing, and power during training drills can decrease the risks on any athletic team or individual. Plyometrics are used with many teams to create muscle memory that will protect the knee joint from many kinds of injuries.2

References:

1ACL injury. (2015). Retrieved June 12, 2016, from http://www.mayoclinic.org/diseases-conditions/acl-injury/home/ovc-20167375

2Torn ACL Symptoms, Recovery, and Surgery. (n.d.). Retrieved June 12, 2016, from http://www.medicinenet.com/torn_acl/article.htm