Anterior Cruciate Ligament Reconstruction

Minimally Invasive All-Inside Technique for ACL Tears

ACL Reconstruction2024-03-02T12:14:35-10:00

Repair Your Torn ACL

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Choose Dr. Morton as your Anterior Cruciate Ligament Surgeon

What is an Anterior Cruciate Ligament Tear?

The knee is composed of multiple ligaments, cartilage, and bones. One of the ligaments responsible for stabilizing the knee, the Anterior Cruciate Ligament, is also the most commonly injured ligament. Orthopedic surgeons can offer multiple treatment options based on the patient’s goals.

Specialized Sports Care

The Anterior Cruciate Ligament and the Knee

The knee is a joint where different bones meet. The thigh bone, the femur, meets the two shin bones, the tibia, and the fibula. The patella is a small bone that sits on the front of the knee. The ends of the thigh and shin bones are covered in cartilage, which helps the bones glide smoothly while walking.

There are several ligaments that provide the entire joint with stability. The Anterior Cruciate Ligament, otherwise known as the ACL, is the most well-known. It prevents the shin bones from sliding forward. There is also a Posterior Cruciate Ligament, the Medial Collateral Ligament, and the Lateral Collateral Ligament. They provide stability for different parts of the knee.

The Anterior Cruciate Ligament

Causes of ACL Injury

Most people have heard of an ACL injury, often in a sports context. While it is true that most ACL injuries occur in athletic events, there are multiple mechanisms of injury. In an athlete, an ACL injury most commonly occurs while running or jumping and changing direction or pivoting that involves rotation and lateral bending of the knee. ACL injuries may also occur when the patient suffers a blow to the side of the knee. Lastly, ACL injuries can occur through high-energy impacts, like motor vehicle collisions.

People who have an ACL injury often feel a “pop”, have immediate swelling, and experience the sensation of an unstable knee. While they can often still walk, they have difficulty with other movements, like squatting or pivoting, that require more stability in the joint.

ACL Tear Diagnosis

When you come into the clinic, Dr. Morton will obtain an x-ray of your knee. This is to look for any other causes or injuries you may have sustained at the same time. After examination, he will evaluate if your knee feels unstable. Based on clinical exam, we will discuss whether you need to have an MRI performed to evaluate your injury. An MRI would also be able to look for other causes of your knee pain such as another ligament injury, cartilage injury, or meniscus tear.

Treatment for ACL Tears

Immediately after the injury, the first priority is rest, ice, compression, and elevation of the injured knee. Surgery need not happen immediately, and in fact often occurs a few weeks to months afterwards if the patient chooses surgery at all.


There are some patients who may be better suited for non-operative treatment. Choosing whether to operate depends on the extent of the injury and the patient’s activities and goals. For example, if a patient is older, less active, and still retains a reasonable amount of function with their injury, non-operative management may be the best option. Often, this involves physical rehabilitation.


Surgery involves reconstructing the ligament itself. The surgeon does this through the use of grafts, meaning that they take another tendon and fashion it into a ligament. There are a variety of graft choices. Surgeons can take a tendon from the patient or from a donor. The three most common tendon grafts are either the quadriceps tendon, the patellar tendon, or a tendon from the hamstring. The quadriceps and patellar tendons have the advantages of increased strength and better fixation to the bone. However, it may cause some more knee pain if taken from the patient. Using the hamstring causes less knee pain, can be very strong, but theoretically has slower fixation than the patellar tendon. Lastly, the surgeon can use a tendon from a donor. The advantage of the donor’s tendon is simply that using a donor avoids taking a tendon from the patient. The patient then does not experience the pain associated with using their own tendon. However, a donor tendon may integrate slower than a tendon taken from a patient. There is also the risk of infections from the donor.

Often there will be other co-existing injuries. Any injury to the meniscus, cartilage, or other ligaments will be addressed at the time of surgery.

ACL Reconstruction Graft Choices

ACL reconstruction is a pivotal procedure for athletes and active individuals aiming for optimal knee stability post-injury. Selecting the right graft is crucial for success, and science provides clear guidance on the options:

Bone-Patellar Tendon-Bone (BPTB): Known as the gold standard, BPTB grafts offer a low risk of re-rupture due to their robust bone-to-bone healing. However, they’re associated with a higher incidence of anterior knee pain, which might affect long-term comfort and functionality.

Quadriceps Tendon: A newer option, the quadriceps tendon graft offers comparable strength to BPTB grafts with potentially lower donor site morbidity. Its robust nature makes it an increasingly popular choice among surgeons and patients for its balance of strength and recovery profile.

Hamstring Tendon: Preferred for its less invasive nature, the hamstring tendon graft poses a slightly higher re-rupture risk compared to BPTB. It’s favored for the reduced donor site morbidity and quicker recovery times, making it a viable option for many patients.

Allografts: Utilizing donor tissue, allografts present a higher re-rupture risk than autografts but eliminate donor site pain. They are often considered for individuals who may not be autograft candidates for various reasons, including previous surgeries or personal preferences.

Each graft type has its niche, balancing re-rupture risk, recovery trajectory, and patient comfort. Understanding these options, backed by scientific evidence, empowers patients and surgeons to make informed decisions tailored to individual needs and goals for a successful return to activity.

All-inside ACL Reconstruction

There are multiple techniques used in ACL reconstruction. The anatomic all-inside technique is a newer technique. By placing the ACL in an anatomic position, it is less likely to fail. The all-inside technique involves using specialized instruments that only drill on the “inside of the knee” and does not drill into the hard outer shell of the bone. The all-inside technique involves less bone removal and can be done with smaller skin incisions. Studies have shown that patients who undergo the all-inside technique have less knee pain compared to those who undergo the traditional technique. This is true as far out as 2 years postoperatively. Studies also show that the knee function scores and the joint anatomy outcomes are the same as the traditional method.

After surgery, patients have to undergo a significant period of physical rehabilitation. The rehab emphasizes joint mobility and strength. In patients who are hoping to return to sports, rehab may last as long as 9 months.

ACL repairs failed in the past as the normal synovial fluid in the joint would prevent the healing of this ACL. This process is called resorption, where your body slowly breaks down and absorbs the repair over time.

So surgeons began searching for a way to encourage your body to accept the repair and enable it to heal on its own. The first major breakthrough in this area was the development of the autograft, which uses a tendon from another part of your body to replace your ACL.

While this method was an improvement, it still had its limitations as the new tendon was not always as strong as the original. Additionally, there was still the risk of resorption, albeit to a lesser extent.

The use of an allograft uses a tendon from a deceased donor. This method eliminates the need to harvest a tendon from another part of your body, but there is still the risk of resorption as your body may reject the allograft. In addition, allografts are not as strong as autografts and have a higher failure rate, especially in younger patients.


The anterior cruciate ligament (ACL) is a commonly injured ligament in the knee that is vital for movement. There are nonoperative treatment options and surgical management options available. Surgery is tailored to each patient’s needs. There are multiple grafts a patient could choose from and multiple techniques a surgeon uses. The all-inside technique results in the least amount of pain while preserving the technical successes of the traditional approach. Ask Dr. Morton about your options in regard to having an ACL reconstruction surgery.

Frequently Asked Questions about Anterior Cruciate Ligament Tears (FAQ)

What does an ACL rupture feel like?2021-02-27T19:57:43-10:00

When you tear your ACL, patients often feel a sudden pop and their knee will give out from underneath them. Usually you will feel very unstable after the injury, as though your knee is “floppy”. Many patients will experience significant swelling and pain. The swelling and pain will gradually resolve. Without treatment, many patients continue to have discomfort and difficulty walking. It is important to see an orthopedic surgeon to make sure you have your knee addressed appropriately.

Can your ACL tear heal on its own?2021-02-27T19:54:31-10:00

Minor, partial tears may not cause your knee to feel unstable, and you may be able to function fine. Complete tears of your ACL will not heal without surgery. Unfortunately, the ACL is located in an area of the knee joint that it will not heal on its own. However, some patients who are lower demand can consider a rehabilitation program to strengthen their knee and successfully manage their ACL tear without surgery.

Can you delay your ACL surgery?2021-02-27T19:54:06-10:00

Patients who are less active may consider delaying their surgery if they have other obligations. However, patients who continue to perform high levels of activity are placing the cartilage and meniscus at risk for further injury. Further injury to the knee can lead to arthritis later in life.

Can you walk after an ACL tear?2021-02-27T19:53:50-10:00

Yes, you can walk. Often times the knee is very swollen after the injury. Once you recover from the initial injury, However, without an ACL patients sometimes feel unstable. Patients who are athletes or require the use of their knee for high demand activities that involve pivoting or jumping are more likely to desire an ACL reconstruction.

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