ACL tears and ACL reconstruction:

Initial injury:

ACL tears can be devastating injuries in any population.  ACL tears most commonly occur during sports activities and can occur in athletes of all sorts.  Younger high school athletes, college athletes or any individual that continues to be active is at risk for an ACL tear.  A non-contact injury typically causes an ACL tear.  This occurs when the knee doesn’t experience any specific hit from another person to the knee.  ACL tears are commonly caused by a twisting injury to the knee or a plant and twist injury to the knee.  However, direct blow injuries can occur.

A “pop” is commonly heard or felt during an ACL tear, but that is not always exclusively the case.  A great amount of swelling, known as an effusion, will almost always occur in the knee.  An effusion in the knee is a sign that something may be torn including the meniscus, cartilage, ACL or PCL.

Common Sports:

Cutting sports such as soccer or football experience ACL injuries much more commonly than other sports.  Women are more likely than men to have an ACL tear for a variety of different reasons.  Particularly, women’s soccer appears to have the highest rates of ACL tears.  However, men overall have more ACL injuries due to playing more sports and activities that lead to ACL injuries.  Although we see a lot of ACL injuries during the ski season, it is less common for experienced skiers to sustain an ACL tear than the general population.  Many inexperienced skiers, however, sustain these injuries at a high rate.  Regardless of sport, the ACL plays a key component in knee stability, particularly in cutting activities. An ACL reconstruction is the best way to restore this stability.

Anatomy of the ACL:

The anteromedial (AM)  and the posterolateral (PL) bundles make up the two major bundles of the ACL.  The AM bundle is responsible for restricting anterior translation of the tibia from the femur. The PL bundle is responsible for preventing significant rotation of the knee.  During physical exam, anterior translation of the knee is testing using the lachman exam. To evaluate abnormal rotation of the knee, the pivot shift test is used.

Although preventing anterior translation of the knee is important, it is often the rotation of the knee that continues to cause the most issues with an ACL tear.  This is often experienced as the knee buckling or going out with twisting activities.  An ACL reconstruction recreates the ACL in the proper position to prevent this instability of the knee.  It is of utmost importance to place proper tunnels when performing an ACL reconstruction, otherwise instability may persist.

Pre-surgical planning, ACL Tear:

Whether seen at our clinic in Rochester, MI or Shelby Township, MI, our initial plan is the same for an ACL injury.  It is important to immediately control swelling by using ice daily and a brace and crutches as needed.  While controlling swelling, it is important to begin to regain full knee range of motion.  Physical therapy can help aid in reducing swelling and increasing range of motion prior to surgery.  Physical therapy is available at our office in Rochester, MI as well as Shelby Township, MI.  An MRI of the knee will also need to be obtained prior to surgery.


An MRI of the knee is important to evaluate the tear of the ACL.  This is important because in some cases, there is the possibility of repairing the ligament.  It is also important to evaluate for a tear of the meniscus, damage to the cartilage or a tear of the MCL or LCL.  With an acute ACL tear, the medial meniscus or lateral meniscus can commonly be torn.  The lateral meniscus is more commonly injured with an ACL tear, but the medial meniscus can be torn as well.  It is important to address the meniscus at the time of ACL surgery.  The meniscus be repaired if possible or trimmed to a stable base.  It is important to repair the meniscus if possible because this will help provide secondary stability to the knee.  Preserving the meniscus also helps to protect the cartilage by dispersing forces in the knee.

When am I ready for surgery?:

A discussion will be had to first determine if an ACL reconstruction is right for you.  An ACL reconstruction in some instances may not be recommended. In most instances, however, if you wish to return to sport, an ACL reconstruction is the best option to return.

There are multiple options for an ACL graft.  Grafts that can be used include the hamstrings, a portion of the patellar tendon (bone-tendon-bone or BTB), a portion of the quadriceps tendon or an allograft (cadaver tissue).  Because the rate of re-rupture is much high in younger patients using allograft, I would only recommend allograft tissue only in older patients.  Most commonly, I would recommend a BTB autograft as this allows healing into bone.  Professional athletes and high level athletes also most commonly receive a BTB autograft.  However, a quadriceps or hamstring graft is a viable option.

The surgery is performed using arthroscopy.  Any repair or trimming that is needed to the medial meniscus or lateral meniscus is performed at the same time.  Full weight can be placed on the leg after surgery while wearing a brace.  However, only partial weight is allowed on the leg if you have a meniscus repair.


Recovery after ACL reconstruction involves a team approach.  Full recovery takes time to allow the graft to heal and regain full strength of the leg.  Initially, the goal is to begin to activate the quadriceps muscle as this becomes very weak after surgery.  Also, regaining full knee range of motion is important.  Once full knee range of motion is regained, more strengthening and activation of the quadriceps muscle can begin.  The new ACL graft in the knee also takes time to heal.  Initially, the graft is healing into the bone and this takes time for complete healing.

At about 3 months, you can start running in a straight line as the graft is strong enough to endure this activity.  Cutting and agility exercises will gradually begin after this time as well.  You will continue strengthening all throughout this process as your leg takes time to get as strong as the other leg.  The graft is then going through a process called ligamentization.  During this time, the tendon used for reconstruction becomes a natural ligament.  This ligamentization as well as obtaining full leg strength are the main reasons it takes over 9 months to return to full sport activity.  Physical therapy aids the whole recovery process.  Physical therapy is available in Rochester, MI or Shelby Township, MI as well as strengthening on your own at home.


Once you are fully recovered, you should expect a stable knee and return to the sport and activities that you love.  Although an ACL tear can be a devastating injury, Dr. Nate Marshall and his team in Rochester, MI and Shelby Township, MI are here to help you through the process and give you the best result.  For more information, visit our website at or call (248) 650-2400 in Rochester or (586) 254-2777 in Shelby Township for more information.

Nate Marshall, MD