Anterior Cruciate Ligament (ACL) Tears




What does the ACL do?

Perhaps the most important ligament in the knee is the anterior cruciate ligament (ACL). It is no bigger than your little finger and runs from the front of your shinbone (tibia) to the back of your thighbone (femur). The ACL has several functions:

  • It provides stability to the knee when twisting or turning.
  • It prevents the tibia from moving forward relative to the femur.
  • It is crucial to activities that require quick cutting and pivoting.

What types of ACL injuries are there?

There are three degrees of ACL sprains:

  • In a first-degree sprain, the ligament fibers are stretched but not torn.
  • In a second-degree sprain, some of the fibers are torn but others remain intact.
  • In a third-degree sprain, all of the ligament fibers are torn, resulting in an ACL-deficient and inherently unstable knee.

How do ACL injuries happen?

There are two common ways that the ACL is injured:

  • In the first situation, the individual may be running and quickly cut or pivot. This results in excessive stress and subsequent sprain of the ligament.
  • The second scenario involves someone or something falling onto the knee while it is fixed in place. This excessive amount of force results in a strain on the ligament.

What are the symptoms of an ACL injury?

Symptoms of an ACL injury include:

  • Hearing or feeling a “snap” or “pop” in the knee
  • Immediate swelling and pain in the knee
  • Difficulty walking without assistance
  • Persistent knee instability, especially when running or pivoting on the knee

It is not uncommon to damage other structures in the knee with the initial ACL injury. This includes disruption of other ligaments, tendons, and/or cartilage of the knee. These other injuries can result in more pain and increased swelling, and complicate the diagnosis and treatment.

How is an ACL tear diagnosed?

In order to determine the cause of your symptoms and the extent of the injury, your doctor will ask you questions and perform a physical examination. X-rays are helpful in viewing the bony anatomy of the knee and can confirm or eliminate a diagnosis.

After your doctor has conducted the examination, he or she may recommend that you undergo more diagnostic tests, such as an MRI (magnetic resonance imaging) scan. An MRI allows your specialist to clearly see the muscles, tendons, and ligaments of the knee. This information helps him or her formulate a treatment plan tailored to your needs.


What are the treatment options for an ACL injury?

The decision to proceed with surgical versus nonsurgical treatment is determined by the patient’s overall health and physical activity. There is a consensus among orthopedic surgeons that in a physically active patient, a torn ACL requires surgical reconstruction. Without an ACL, the knee is inherently unstable, and the patient risks further injury when participating in activities.

Immediately after injury, the treatment plan is focused on reducing the patient’s pain and swelling while increasing knee strength. Physical therapy can be very useful in this regard, and your specialist may wish that you see a physical therapist prior to surgery. If this is the case, surgery can be scheduled once the pain and inflammation are under control.

What happens during ACL reconstruction surgery?

ACL reconstruction is performed arthroscopically to ensure proper graft placement and minimize the risk of complications.

  • The old, torn ligament is removed
  • The ligament is replaced with a new graft harvested from one of several sources.
    • An autograft is when the new ligament is harvested directly from the patient’s own patellar or hamstring tendon.
    • An allograft is harvested from an outside source.

What can I expect during recovery from ACL surgery?

  • After surgery, you can expect to be in a brace for up to a month.
  • Approximately one week after surgery, you will see your specialist and begin physical therapy. The goal of these sessions is to decrease the postoperative pain and swelling while increasing your strength and range of motion.
  • As your knee starts to feel better and the graft begins to strengthen, your specialist and physical therapist will clear you for increased activity.
  • A brace may be prescribed for you to wear during athletic activities.

What is cold compression therapy, and why did my doctor recommend it?

Your doctor may prescribe a cold compression therapy unit for you to use after your surgery. Integrated cold and compression is clinically proven to:

  • Reduce postoperative swelling
  • Decrease pain
  • Help you regain range of motion

Summit Orthopedics believes that the cold compression therapy unit will provide you with the best possible outcome in the days following your surgery.

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