KneeŞişli, Istanbul
ACL injury treatment
The anterior cruciate ligament prevents the shin bone from sliding forward on the thigh bone and from rotating excessively. Injury usually occurs through a non-contact mechanism during a sudden stop or change of direction.
Also known as: ACL tear, anterior cruciate ligament rupture
What is it?
Most ACL injuries are non-contact: the athlete's knee collapses inward during a sudden stop, landing or change of direction and the ligament cannot absorb the load. A 'pop' is often heard at the moment of injury, the knee swells rapidly and continuing the activity becomes impossible.
The ACL does not heal on its own; a torn ligament does not reunite. That does not mean everyone needs surgery. The decision depends on age, activity level, sporting goals and whether the knee gives way. Reconstruction is commonly chosen for young athletes returning to cutting sports; in lower-demand individuals, non-surgical management with good rehabilitation can be viable.
Whatever the surgical decision, rehabilitation is decisive. Patients who achieve full range of motion and good quadriceps strength before surgery have markedly better outcomes afterwards. 'Prehabilitation' is therefore a stage that should not be skipped.
Symptoms
- A pop heard or felt at the moment of injury
- Marked swelling developing rapidly within the first few hours
- A sense of the knee giving way and feeling unstable
- A feeling of the knee shifting when turning or changing direction
- Inability to fully straighten the knee
- Rapid wasting and loss of strength in the quadriceps
- Insecurity that becomes obvious descending stairs and on slopes
Causes and risk factors
- Sudden deceleration and change of direction — the non-contact mechanism
- Landing from a jump with the knee collapsing inward
- Weakness in the hip and gluteal muscles
- Strength imbalance between the front and back thigh muscles
- Poor landing technique and lack of neuromuscular control
- A direct blow to the knee (less commonly)
The assessment
The mechanism, any pop and how quickly swelling developed are explored — swelling within the first hours suggests bleeding into the joint and a significant injury. Ligament stability tests such as Lachman and pivot shift are used, with Lachman the most reliable examination finding.
Meniscal and collateral ligament injuries are also checked, since ACL injuries frequently do not occur alone. Range of motion, swelling and quadriceps strength are recorded. These measurements influence both the starting point of rehabilitation and the timing of surgery.
Course of treatment
Weeks 0–3
Settling and full extension
Swelling is brought under control and full knee extension restored. Delaying this goal increases the risk of permanent restriction after surgery. Quadriceps activation is started early.
Weeks 3–10
Building the strength base
The quadriceps, hamstrings and gluteal muscles are strengthened systematically. Where surgery is planned this period is prehabilitation and directly improves outcomes.
Months 3–6
Control and power
Balance, proprioception and landing technique are trained. The strength difference between sides is measured and tracked, with the target of reaching at least 90% of the uninvolved side.
Months 6–12
Return to sport
Running, jumping, cutting and sport-specific movements are added progressively. The decision to return is based not on elapsed time but on hop test and strength measurement results.
How long does it take?
ACL rehabilitation is a long process. With non-surgical management, clear functional gains are achieved in three to six months. After reconstruction, full return to sport usually takes nine to twelve months; returning early markedly increases the risk of re-injury, so the decision is based on objective test results.
When to see a doctor
The findings below fall outside the scope of physiotherapy and require medical assessment.
- Complete inability to bear weight on the knee
- Obvious deformity — suspicion of knee dislocation
- Numbness, coldness or absent pulses in the leg
- Fever, redness and warmth
- The knee locking completely
- Pain that increases rapidly after injury and becomes unbearable
Frequently asked questions
Is it possible to recover without surgery?
It is possible for some patients. In activities without cutting, and in people whose knee does not give way, non-surgical management with good rehabilitation can succeed. The decision is made together with your activity goals and examination findings.
Is physiotherapy needed before surgery?
It is important enough to be considered essential. Patients who go into surgery with full range of motion and good quadriceps strength have markedly better outcomes and a lower risk of post-operative stiffness.
When is it possible to run?
Return to running usually begins around three to four months after surgery, once strength and control criteria are met. Measurement rather than the calendar decides; starting early increases re-injury risk.
Is there a risk of re-tearing?
Yes, and the risk rises markedly with early return and insufficient neuromuscular control. Return criteria are therefore kept strict, with extended work on landing technique and hip strength.
Methods used
Related conditions
The content on this page is for information only and does not replace medical diagnosis or treatment. Always consult a healthcare professional about your symptoms.
Assessment appointment
No referral is required for assessment. Enquiries regarding ACL injury treatment may be submitted via WhatsApp; available dates and times will be provided in response.