Authored by Revere Health

Understanding ACL Tear Causes, Symptoms and Treatments

July 29, 2016 | Sports Fitness and Physical Therapy

ALC Treatments

The repercussions from a tear in your anterior cruciate ligament, or ACL, go beyond ruining your day out hiking or landing you on the bench during your sports game. This type of injury can actually cause a lifetime of pain and mobility issues if it goes untreated by a qualified medical practitioner.  The ACL is a major ligament that runs through your knee and attaches your thighbone to your shinbone. This ligament keeps your leg bones aligned and helps stabilize your knee.

After suffering a torn ACL, your shinbone might rotate or move too far forward as you take each step. Until you undergo treatment to repair the damage, your knee will feel unstable and could buckle when you put weight on it. An ACL tear also increases the risk of damaging the cartilage and meniscus in the affected knee. Understanding the causes, symptoms and treatment for ACL tears can prepare you to handle this injury before complications develop.


Suddenly stopping and changing direction while participating in athletic activities is the most common cause of ACL tears. During these rapid movements, you may plant your foot and rotate your knee, causing the ligament to partially or completely tear. Colliding with other players and landing wrong after jumping also puts excess strain on the ACL and causes injury.

Although athletes suffer from this injury most often, everyone is susceptible to this type of knee injury. With reports of toddlers and elderly individuals suffering this type of damage, it has recently come to light that ACL tears can occur at any age. Gender, however, does play a role in the prevalence of this type of knee injury. Women are actually about four to six times more likely to develop ACL tears and other knee injuries than men due to an imbalance in leg strength and off center body mass.


When the injury occurs, it is common to hear and feel a pop coming from the damaged ligament. Swelling swiftly follows the popping sound, often causing a cascade of pain and stiffness in the injured area. Your full range of motion will be compromised until you have this injury treated. As a result, normal movements, including walking, will likely be difficult and painful. Your inflamed knee will feel tender, so you may have trouble getting comfortable while sitting or lying down.

If your pain levels continue, you might also have trouble sleeping as pain flares can occur when you roll over or adjust your position. In the first few days after the initial injury, you can elevate your leg with pillows and apply ice to keep the swelling and pain to a minimum until you can see your doctor.

The ACL is a major ligament that runs through your knee, keeping your leg bones aligned while also helping to stabilize your knee.

If you decide to wait it out and let the swelling resolve on its own, you will likely experience continued instability and weakness in the affected knee. You might notice your knee starting to buckle as you shift your weight onto that leg. If you pivot your injured leg, your knee could completely buckle under your weight as your knee shifts out of place. The swelling may return at that point, as this movement has the potential to cause additional damage to the ACL and other structures in your knee. Seeking a medical diagnosis and treatment immediately after suffering an ACL tear is the only way to prevent further injury to your knee.


Your doctor must compare your injured and non-injured knee structures to evaluate the damage to your ACL. Imaging tests, including x-rays and MRI scans, allow your doctor to visualize the damage and assess its grade. ACL tears are graded from one to three, depending on their severity. Grade one is a stretched or sprained ligament. Grade two is a partial tear that results in a loose ligament. Grade three is a complete tear that fully destabilizes the knee. Grading your injury will help your doctor come up with a suitable treatment plan designed to fully resolve the damage.



If you suffered a low grade ACL injury, your doctor may want to try to repair the damage and restore your knee function using non-invasive treatment options. Doctors use nonsurgical treatments for children and elderly patients due to the increased risk of complications for these individuals. To help your knee heal without surgery, you will need to attend regular physical therapy sessions and wear a brace.


Surgical repair is usually recommended for all other patients and injury levels. Without this type of care, 90 percent of people with torn ACLs suffer instability and reinjure their leg during normal activities.

During surgery, your doctor will rebuild the torn ligament using a graft of healthy tissue. Your doctor may obtain the tendon graft from your own hamstring or a cadaver donor’s. The surgery is performed using tiny incisions and arthroscopic tools to facilitate a quick recovery time and minimize surgical scarring.

Without proper surgical repair, 90 percent of people with torn ACLs suffer instability and reinjure their leg during normal activities.

Since this surgery is performed as an outpatient procedure, you will not have to spend the night at the hospital unless complications develop. Although the surgery itself only takes about two hours, you can expect to remain at the hospital for up to five hours due to time spent preparing and recovering from the procedure. After the effects of anesthesia wear off and your doctors have your pain under control, you will be sent home to continue recovery.


Although the incision heals quickly due to use of high tech surgical tools and techniques, it can take up to six months for the new tendon material to grow and strengthen along the graft. You will need to avoid athletic activities and attend physical therapy as the tendon rebuilds itself. Your physical therapist will help you regain your ability to bear weight on your knee and increase your activity levels on an appropriate time schedule.

After making a full recovery from ACL surgery, many people regain between 80 to 100 percent of their previous athletic abilities, including strength. Continued physical therapy can prevent scar tissue from growing in and around the knee as it heals and you return to your full activity levels.

Seeking Care For ACL Tears And Other Knee Injuries

If you suspect you damaged your ACL, schedule an appointment with Dr. Michael Carlson at Revere Health to have your knee injury evaluated. Dr. Carlson splits his time caring for patients between the Provo Main Campus, Mountain Point Medical Center and Salem Multi-Specialty Health Center. At your appointment, your doctor will perform a physical examination and diagnostic tests to find the cause of your leg pain and discomfort. After providing a diagnosis, your doctor will discuss the available treatment options for that specific condition. Your doctor will provide ongoing care to help you avoid future injuries to your knees and their surrounding structures.

Dr. Carlson tends to be conservative with surgical treatment, and much of his training is in minimally-invasive procedures, such as arthroscopy. He believes everyone deserves a trial of a more conservative treatment before moving to more invasive treatments such as surgery. Dr. Carlson tries to spend time with patients to better understand their goals and work together to come up with a treatment plan based on those goals and their distinct medical history.

Michael Carlson, MD


Michael Carlson, MD

Telehealth is not appropriate for every medical concern, so it’s important to ask your provider whether a virtual visit is suitable for your needs.

Learn more about Telehealth

This information is not intended to replace the advice of a medical professional. You should always consult your doctor before making decisions about your health.