ACL Tear

What is an ACL tear?

The anterior cruciate ligament (ACL) is one of the main ligaments inside the knee. It helps control forward movement and rotation of the shinbone and provides stability, particularly during running, jumping and sudden changes of direction.

An ACL tear commonly occurs during sports involving pivoting, landing or sudden deceleration, but it can also occur after a fall, collision or other injury.

What are the symptoms of an ACL tear?

Common symptoms include:

• A popping sensation at the time of injury

• Pain and swelling of the knee

• Difficulty bearing weight

• Loss of knee movement

• A feeling that the knee is unstable or “giving way”

A large amount of swelling soon after an injury can indicate bleeding inside the knee and warrants assessment. 

How is an ACL tear diagnosed?

Diagnosis begins with a detailed history and clinical examination. Tests of knee stability help assess the ACL and identify associated injuries.

X-rays may be performed to look for fractures or other bony problems. MRI is particularly useful for confirming an ACL tear and assessing associated meniscus, cartilage and ligament injuries.

What are the treatment options for an ACL Tear?

Treatment may be non-surgical or surgical, depending on the patient's age, activity level, degree of instability, associated injuries and goals.

Non-surgical treatment generally involves rehabilitation to restore movement, strength and knee control. Some patients with lower activity demands and a stable or minimally symptomatic knee may function well without reconstruction.

ACL reconstruction may be considered particularly for active patients who experience instability or wish to return to sports involving pivoting and cutting. Associated meniscus, cartilage or ligament injuries may also influence the treatment decision.

Do all ACL tear needs surgery?

An ACL tear does not automatically mean that surgery is necessary.

Some people can lead an active life with rehabilitation and appropriate modification of activities. However, repeated episodes of the knee giving way can interfere with daily activities and sport and may place additional stress on the meniscus and other structures of the knee.

The decision therefore depends less on the MRI alone and more on how the knee functions and what the patient wants to return to doing.

When might surgery be recommended?

Reconstruction is more likely to be considered when there is:

• Recurrent instability

• A high level of sporting activity

• A physically demanding occupation

• Associated meniscus or cartilage injury

• Multiple ligament injuries

• A desire to return to pivoting or cutting sports

What type of surgery is recommended for an ACL tear?

The type of surgery depends on the type and location of the ACL injury. ACL reconstruction is usually recommended when the ACL is completely torn and the knee remains unstable. In some injuries, the ACL may pull away from its attachment along with a small piece of bone. In such cases, ACL avulsion fixation may be possible to repair the ACL back to its original attachment.

What happens after ACL reconstruction?

Rehabilitation begins early after surgery and progresses through stages of restoring movement, strength, balance, running and sport-specific function.

When can I return to normal activities?

Recovery after ACL reconstruction is gradual and depends on the type of work, the condition of the knee and progress with rehabilitation. As a general guide, most patients should plan for at least 6 weeks before returning to regular work. People with desk-based or less physically demanding jobs may be able to return earlier, while jobs involving prolonged standing, walking, climbing, squatting or heavy physical work may require longer. Your surgeon and physiotherapist will guide your return based on your individual progress.

When can I return to sports?

Returning to sports takes considerably longer than returning to everyday activities or work. As a general guide, return to running and sport-specific training usually begins only after several months of rehabilitation, while return to unrestricted pivoting and contact sports is usually not considered before 6 months and often takes 9–12 months. The exact timing depends on strength, knee stability, movement control, psychological readiness and sport-specific testing—not simply the time since surgery.

When should I see an orthopaedic surgeon?

If your knee repeatedly gives way after an ACL injury, you should seek assessment by an orthopaedic surgeon. Recurrent instability can affect everyday activities and may place additional stress on other structures of the knee, including the meniscus. Assessment is particularly important to determine the extent of the injury and whether treatment with rehabilitation alone or ACL reconstruction would be more appropriate.