ACL Tears

The knee joint is formed by three main bones: the femur (thighbone), tibia (shinbone), and patella (kneecap). Four major ligaments stabilize the joint:

• The anterior cruciate ligament (ACL), which prevents the tibia from sliding forward relative to the femur.
• The posterior cruciate ligament (PCL), which prevents the tibia from sliding backward relative to the femur.
• The medial and lateral collateral ligaments (MCL and LCL), which stabilize the sides of the knee.

The ACL runs diagonally through the center of the knee, crossing in front of the PCL, forming an “X” shape that gives the cruciate ligaments their name. This unique positioning allows the ACL to control both forward motion and rotational stability.

The knee also contains menisci, which act as shock absorbers and help distribute weight evenly. When the ACL tears, the entire joint can become unstable, increasing the risk of meniscus and cartilage injury if not properly treated.

ACL injuries are extremely common, especially in young, active individuals. In the United States alone, more than 200,000 ACL injuries occur each year, and approximately half require surgical reconstruction.

Risk factors include:

• Participation in cutting and pivoting sports such as soccer, basketball, football, and skiing.
• Female sex, due to differences in anatomy, muscle control, and hormonal influences.
• Weak or imbalanced leg muscles, particularly in the hamstrings and quadriceps.
• Previous ACL injury, which increases the risk of re-injury.

ACL tears can happen through non-contact mechanisms (such as landing awkwardly or pivoting sharply) or through direct contact, like a collision during sports.

Diagnosis begins with a detailed history and physical examination. Dr. José Vega, Cleveland’s trusted knee specialist, will ask about the mechanism of injury, the timing of symptoms, and whether you experienced a popping sensation or rapid swelling.

During the exam, Dr. Vega will assess for joint swelling, tenderness, range of motion, and stability. Specific tests—such as the Lachman test, anterior drawer test, and pivot-shift test—help evaluate ACL integrity.

Imaging studies are often ordered to confirm the diagnosis and identify any associated injuries:

• X-rays rule out bone fractures.
• MRI provides a detailed view of the ACL, menisci, cartilage, and other soft tissues.

Because ACL tears can occur alongside meniscus tears, cartilage injury, or bone bruising, a complete evaluation is essential before creating a treatment plan.

Treatment depends on the severity of the tear, patient activity level, and overall knee stability.

Nonsurgical treatment may be appropriate for partial tears, older or less active patients, or those willing to modify their activities. It includes:

• Bracing and activity modification to reduce instability.
• Physical therapy focused on restoring range of motion, strength, and balance.
• Anti-inflammatory medications to relieve pain and swelling.

However, for most active individuals—particularly athletes—a complete ACL tear typically requires surgery to restore stability and prevent further joint damage.

ACL reconstruction involves replacing the torn ligament with a graft, which may be:

• Autograft (patient’s own tissue), commonly from the patellar tendon, hamstring tendon, or quadriceps tendon.
• Allograft (donor tissue), used in select cases such as older individuals, revision ACL surgery or multi-ligament injuries.

ACL repair is actually an old technique that has recently increased in popularity due to advances in biotechnology. While traditional ACL repair techniques involved stitching the torn ACL back together, modern ACL repair is enhanced with a special implant known as BEAR. While this procedure is reserved for a very specific subset of patients with recent ACL injuries, it is the only option to repair or re-grow a torn ACL. If ACL repair with BEAR interests you, please ask Dr. Vega about your eligibility for this procedure.

ACL surgery is performed arthroscopically through small incisions, minimizing recovery time and scarring.

After surgery, a structured rehabilitation program is crucial for success. Therapy focuses on:

1. Reducing swelling and restoring full extension.
2. Regaining strength in the quadriceps, hamstrings, and hip muscles.
3. Improving balance, agility, and confidence in the knee.

Most patients return to sports between 6–9 months after surgery, depending on healing progress and functional recovery.

While not all ACL injuries can be prevented, research shows that neuromuscular training programs can significantly reduce risk—especially for female athletes.

Preventive strategies include:

• Strengthening the core, hips, and hamstrings to improve knee control.
• Jump training to teach safe landing mechanics.
• Agility and balance exercises to enhance stability.
• Proper warm-up routines before sports or training.
• Using appropriate footwear and playing surfaces to reduce slipping or twisting forces.

Consistency with these exercises—especially during pre-season and early training phases—has been shown to cut ACL injury risk by up to 50%.