ACL Overview

Knee injuries can be devastating to any athlete and with athletic seasons in full swing they are unfortunately common. The most dreaded of these injuries is the anterior cruciate ligament (ACL) tear. This injury can leave young athletes sidelined for months as they work to recover from her injury. Although surgery is not always necessary, an ACL tear leaves the knee feeling unstable making cutting and pivoting sports almost impossible. When an athlete desires to return to such sports, an ACL reconstruction is often necessary.

The ACL ask as a link between the thigh bone (femur), and the lower leg bone (tibia). By linking the two bones together it prevents abnormal motion between the two. It allows the knee to flex and extend but prevents abnormal rotation or forward motion of the tibia against the femur. When this link is torn an athlete will feel unstable especially when cutting, pivoting or jumping. This instability puts the knee at risk for other injuries including tears of the cartilage/meniscus.

Athletes are often surprised to hear that an ACL can be torn without any impact to the knee. In fact, the most common mechanism for ACL tear is a non-impact twisting injury. This can occur when a player lands in an awkward position from a jump or plants the foot while twisting around the knee. ACL tears can also occur when the knee is hit from the side like during a tackle in football or soccer. When the ACL tears athletes will often feel a pop in the knee and usually have pain. Often times however, an athlete will be able to stand up, walk and sometimes will even try to return to play. When they do, they often feel instability and the knee may give out on them.

There are several sidelined tests that an athletic trainer or physician can perform to help diagnose an ACL tear. Ultimately, athletes will require a MRI to assess the ACL and other structures in the knee. In many cases, there may be associated injuries to the meniscus or cartilage of the knee. When the diagnosis is confirmed, athletes and their physicians need to discuss whether surgery is necessary. If an athlete desires to return to athletic activity especially pivoting, cutting, and jumping sports then an ACL reconstruction is recommended. If the patient is not interested in athletics they may be treated without surgery.

When surgery is chosen, it is important for athletes to understand that the ACL cannot be repaired but is, in fact, replaced. The replacement ACL can come from the patient or from a donor. Young athletes tend to have better results when the new ACL comes from their own bodies. This is called an autograft. Autografts can either be taken from a tendon in the front of the knee called the patellar tendon or from tendons in the back called the hamstrings. Both grafts are very strong and work well. Each has its unique pros and cons and these are important to discuss with your surgeon. In lower demand or older athletes donor grafts can be used. These donor grafts (allograft) are often easier to recover from as they require slightly less surgery.

Regardless of the graft choice, recovery from ACL surgery usually takes 6-10 months. This timeline is mostly based on the time required for the body to strengthen the new graft. In the first few weeks after surgery athletes work on strength and range of motion. After several months they begin to work on endurance, speed, and agility. Our goal after surgery is to make the operative leg at least as strong if not stronger than the other leg. After several months it is easy to become impatient as the surgical knee feels relatively normal, and athletes feel as though they could return to play. This is a dangerous time because the new ACL graft is still weak and prone to injury. Athletes are eager to return to play but must be patient with their progress.

Recovery from ACL surgery requires a team approach. This includes participation from the patient, family members, physical therapist, athletic trainers, coaches, doctors and nurses. Each has an important role to play in getting the athlete back to their sport and stronger than ever. Our goal with ACL surgery is to get patients back to the activities that they love feeling strong and confident about their knee.