What Is the Difference Between an ACL Tear and an MCL Tear?

For athletes, one of the most dreaded injuries they can sustain is an ACL or MCL tear. With an ACL or MCL tear, an individual can expect to sit on the sidelines for months, or possibly longer, depending on the severity of the injury. But while people commonly associate the two knee injuries with each other, they are actually very different. Learn the difference between the two here.


What Are ACL and MCL Ligaments?

There are different ligaments that are in your knee joint, and that stabilizes the bones. The ligaments include the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL) and lateral collateral ligament (LCL). Knee injuries can damage any of these ligaments but the ACL and MCL are the most common injuries.

The ACL is in the middle of the knee joint which prevents the femur from sliding backward on the tibia. The MCL spans the inner side of the knee, spanning from the end of the femur to the top of the tibia. The MCL prevents the femur from sliding side to side.


How do I know if I seriously injured my knee?

You will know right away if you have hurt a ligament in your knee. Swelling will occur quickly because a tear will bleed out into the knee. Most people will notice that they have hurt their knee by the sound and feeling of a pop. If swelling and pain occur, then you should see a doctor right away.

If you’re unable to see a doctor right away, you should do the following steps:

  1. Rest.
  2. Use ice to reduce swelling
  3. Compression – using an elastic bandage or brace.
  4. Elevation.


What steps should I take to avoid injuring or re-injuring my knee?

For all athletes that have injured their knee or want to avoid injuring their knee we recommend trying the following:

  • Use a protective knee brace during sports and exercise.
  • Muscle-strengthening exercises.
  • Limit your activities and allow the knee to heal.


If I tear my ACL or MCL, is surgery necessary?

If you take the necessary steps in allowing a torn ACL or MCL ligament to heal, in most cases surgery is not needed. However, if the injury is severe enough, there is always the possibility that surgery will be necessary.

If someone injures their MCL ligament the first step in the healing process is rehab therapy. Therapy can take two or more months before the ligament is fully healed.

An ACL injury is more complex. This is because there are multiple ligaments within the ACL. In more than half of injuries involving an injured ACL it won’t heal by itself and will often require surgery. The type of surgery needed for an ACL injury is called “ligament reconstruction”, in surgery the ACL ligaments are unable to be sewn back together. What happens in an ACL ligament reconstruction, is tendons from the patellar or hamstring is used to reconstruct the ACL ligament. The recovery time for this type of surgery is 8-12 months.


5 signs to determine if you have a serious knee injury:

  1. Swelling – did your knee swell immediately or shortly after you injured it? This is a common sign that means there is a possibility you may have sustained a serious knee injury and a torn About 80% of people that have felt and heard a pop or have developed blood in the knee, will either have an ACL tear or patella dislocation. With either of these conditions, the patient will find it hard to walk due to severe pain.
  2. Locked Knee, Unable to Straighten It – if you hurt your knee and are unable to straighten your leg due to the injury, this can indicate that you may have a locked knee. The most common name of this injury is called a bucket handle tear, which is a meniscus tear.
  3. Unstable Knee or You feel a Pop – if you felt or heard a pop in your knee, then there is a possibility that you may have torn your ACL ligament. Most ACL injuries are not from direct contact with the knee, but rather a twisting or pivot.
  4. Weakness When Trying to Straighten Your Knee – even a few days after a knee injury, if you’re still having troubles straightening your knee it could mean that you suffered a serious knee injury. Most causes include patella dislocations, patella tendons tears or quadriceps tears.
  5. Difficulty Walking – for all knee injuries this is one of the most common issues, is difficulty walking. Anyone that has a serious knee injury should be evaluated by an orthopedic surgeon to determine how serious the injury is.

Knee injuries are very common when it comes to all sports and physical activities, but most cases aren’t serious. Identifying a severe knee injury and acting quickly by having a sports medicine physician look at it can make all the difference when it comes to getting you back on your feet and minimizing the risk of further damage.


What Is an ACL Tear?

Four ligaments make up a person’s knee, including the ACL or anterior cruciate ligament. The main functions of the ACL are to steady the knee, keep the knee from turning and to keep the tibia from overextending itself. When an individual injures their ACL, it’s typically because they twisted their knee suddenly or dislocated it.


What Are the Symptoms of an ACL Tear?

Signs and symptoms of an ACL injury usually include:

  • The sounding of a “pop” or a possible “popping” sensation in your knee.
  • Severe pain.
  • Swelling that can start in as little as a few hours.
  • Stiffening in the knee.
  • A feeling of your knee giving way with weight applied to it.


What Are the Causes of an ACL Tear?

Most ACL injuries happen while playing sports or other physical activities that can put stress on the knee:

  • Stopping or changing directions suddenly when running.
  • Pivoting when your foot is firmly planted.
  • Landing from a jump incorrectly.
  • A direct hit to the knee.


What Is an MCL Tear?

The MCL, also known as a medial collateral ligament, is in the inner region of the knee. The MCL works to resist and widen the knee joint. When an individual clip their knee from the outermost part (typically during a contact sport), it can cause the knee joint to widen to the point where it tears apart.


What Are the Symptoms of an MCL Tear?

The symptoms of an MCL injury may include:

  • A popping sound.
  • Pain and/or tenderness in the inner part of the knee.
  • Feeling that your knee is going to give out when weight is put on it.
  • Locking within the knee.


What Are the Types of MCL injuries?

MCL injuries are graded by the following:

  • Grade 1 MCL injury Your ligament most likely has been stretched but not torn. (This one is the least severe)
  • Grade 2 MCL injury – Your ligament has been partially torn. This can cause some instability in your knee joint.
  • Grade 3 MCL injury – This is when your ligament has been completely torn. (The most severe type of injury.)


How is an MCL injury treated?

There are different treatment options for each type of MCL injury. These vary depending on the severity of the injury. Most MCL injuries can heal on their own after a few weeks of rest. Some of the different types of treatments are:

Immediate Treatment:

This type of treatment is to ease the pain and help stabilize the knee. Some treatment options include:

  • Ice for swelling.
  • Elevation of the knee above your heart to reduce swelling.
  • Non-Steroidal Anti-Inflammatory medication for pain.
  • Compression – using elastic bandages or a brace.
  • Rest.
  • The use of crutches to keep weight off the knee.


Rehab is used to help gain strength back in your knee and to prevent further injury. Some types of treatment include:

  • Physical Therapystrengthen the muscle and improve the knees motion.
  • Knee Brace – wearing protection during sports or other activities.
  • Limiting Activities – avoid sports that can cause further damage.


Usually an MCL injury conjunction: will not result in surgery. Order reversal: Surgery is only suggested if all precautions were taken, and the knee would not be able to heal itself. If the tear is where the ligament attaches to either your shinbone or thighbone, your orthopedic surgeon can use one of these methods to help repair the tear:

  • Use of large stitches
  • Bone staples
  • Metal screws
  • Suture anchor


How Can You Tell the Difference Between an ACL Tear and an MCL Tear?

A torn ACL and a torn MCL exhibit similar symptoms. The main difference between an ACL tear and an MCL tear is that an ACL tear will have a distinctive popping sound, while an MCL tear will not. When an individual’s ACL or MCL is torn, they will typically experience these symptoms:

  • Swelling
  • Inflammation
  • Extreme Pain
  • Possible Bruising


Treatment for ACL and MCL Tears

MCL tears are typically easier to recover from than ACL tears. With an MCL tear, the recovery process may take up to eight weeks with rehabilitation. An ACL tear, on the other hand, often requires surgery and at least six months of rehabilitation.


What is a Torn ACL and Torn MCL Recovery Times?

A MCL tear can have a quicker recovery time. Typically, a MCL tear heals within eight weeks or more with rehab. While an ACL tear usually require surgery and at least six months of rehab or more.


ACL and MCL Treatment at Coastal Orthopedics

A torn ACL or MCL is a severe injury that should be assessed and treated by a professional. At Coastal Orthopedics, our team of experienced orthopedic and sports medicine physicians can diagnose your knee injury and provide the appropriate treatment. Give us a call to speak with one of our friendly team members or schedule your appointment online today.