ACL Injury

An injury to the ACL is one of the more common injuries to the knee among athletes and those who participate in recreational sports. The knee is the largest joint in the body which is where the ACL is found. The ACL is attached from the femur (thigh bone) to the tibia (shin bone) and prevents excessive forward motion of the tibia. An injury or tear to this ligament can greatly affect the stability and function of the knee-joint as the ACL is an important stabilizer in the knee-joint.

There are two types of tears to the ACL: a complete tear or a partial tear. Again, any tear to the ACL can result in affecting the function of the knee. When the ACL is torn this results in an excessive rotational movement to the knee which can result in tearing of the meniscus or surrounding cartilage in the knee-joint. It is not unusual to have a cartilage tear along with an ACL tear especially if the injured is an athlete.

So what causes the ACL to tear?

  • The ACL can tear due to excessive knee hyper-extension combined with rotation while the foot is still planted to the ground (usually as a result from a hit directly to the outside (lateral) part of the knee, think of being tackled in football)
  • The ACL can tear due to sudden lateral movement, such as cutting, as performed in basketball or due to a sudden stop or twisting motion to the knee as can occur with fast paced sports such as soccer, tennis, basketball, skiing, or football.

What are the symptoms of a tear and what do I do if I think I tore my ACL?

  • Symptoms: usually hear an audible pop at the time of a tear following by excessive swelling to the knee joint as well as instability with walking as well as a feeling of your knee wanting to “give way” under you when trying to stand or walk. You will also experience a loss of motion when trying to bend or straighten your leg.
  • If you suspect a tear: RICE (Rest, Ice, Compression, Elevation): remember, make sure your leg is elevated above the level of the heart and NEVER place ice directly on the skin. You should try to keep the knee as immobile as possible until you are evaluated by your physician for a possible tear.

Possible treatment options? After undergoing an x-ray or MRI your physician may prescribe conservative care such as physical therapy or recommend surgery. However, it will not be unusual for your physician to recommend pre-operative physical therapy to gain some range of motion and reduce swelling before surgery. You can read more about pre-surgical physical therapy here: physical therapy before surgery

What kind of graft should I use? Since surgery is usually recommended your doctor will discuss different types of grafts you can use to repair the ACL. The reason for the graft is because the ACL will not heal on its own without surgery.

  • Patellar Tendon: This graft usually has very good outcomes and is one of the most common approaches to ACL repair. However, the downside of this graft is that it can result in a more painful rehab as well as weaken the patellar tendon.
  • Cadaver Ligament: As the name suggests this ligament is taken from a cadaver which will be used to reconstruct the ACL. There is less post-operative pain with rehab however you have a higher risk of developing an infection with this graft.
  • Hamstring Tendon: A piece of your hamstring is taken in order to reconstruct the ACL. Again, less pain than the patellar tendon but has a longer healing time as this can weaken your hamstrings. As I stated earlier the ACL helps prevent forward translation of the tibia. If your hamstrings are strong this will also help stabilize the tibia from moving forward in combination with your ACL. This graft can cause weakening of the hamstrings and therefore is not a common approach.

Remember, this decision is YOURS and should be discussed with your surgeon as every individual is different.

How long is physical therapy? If you tear your ACL by a freak accident and you are not an athlete you can expect a 4-5 month physical therapy period. Most athletes, however, can average a 7-8 month period of physical therapy as there is a strict protocol to follow. It is a step by step process in physical therapy to be able to return to high level activities and sport. If you were to return to a sport too soon without the correct rehab there is a chance of re-tear. It will also not be unusual if your surgeon recommends a brace as you return to your sport or athletic activity to help keep the knee stabilized.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s