Autograft or allograft
Autograft is generally preferred in young or active patients because allograft carries a higher failure risk in this group. Allograft remains a selective option rather than an automatically equivalent substitute.
Arthroscopy · knee
Anterior cruciate ligament reconstruction
Replaces the torn ligament with a graft to control instability and protect the meniscus and cartilage during pivoting activities.
General guidance
When it may be considered
- recurrent episodes of the knee giving way
- sports involving pivoting and rapid changes of direction
- repairable associated injuries
- persistent instability despite rehabilitation
Individual decision
How suitability is determined
Whether surgery is appropriate depends on activity level, clinical instability, individual anatomy and any associated meniscal, cartilage or ligament injuries. Graft choice and anatomical tunnel placement are discussed as part of the surgical plan.
An abnormal scan alone is not an indication for surgery. The symptoms, clinical examination, progression and the patient's goals must be considered together.
Surgical plan
Decisions that tailor the procedure
- functional instability and activity goals
- meniscal and cartilage injuries that need to be protected or treated
- graft choice and anatomical positioning of the bone tunnels
- rehabilitation and return-to-sport criteria
Alternatives
What is discussed before surgery
The main alternative is a structured rehabilitation programme, with modification of pivoting activities and, in selected cases, a functional brace. Injections cannot restore the ACL or treat mechanical instability.
Before the procedure
Preparation and safety
- before surgery, the knee should regain full extension, swelling should be controlled and strength restored;
- discuss the choice of graft and the implications of the donor site;
- tell the medical team about diabetes, anticoagulant treatment, allergies, smoking and any active infection;
- do not stop or change long-term medication without instructions from the medical team;
After the procedure
Rehabilitation
Rehabilitation is staged and addresses neuromuscular control, strength and mobility, with functional criteria that must be met before returning to sport.
The exact protocol, permitted weight-bearing and follow-up schedule depend on the procedure performed and individual progress.
Informed consent
Risks and limitations
Possible complications include stiffness, infection, thromboembolism, graft failure, associated injuries and the need for revision surgery.
No procedure can guarantee complete pain relief or a return to a particular level of activity.
After surgery
Signs that require prompt medical assessment
- fever, discharge, spreading redness or worsening pain at the wound;
- sudden swelling of the calf, chest pain or difficulty breathing;
- uncontrolled pain, new numbness, or a change in the colour or temperature of the limb.
For severe symptoms or an emergency, call 112. The instructions given to you at discharge take priority over the general information on this page.
Editorial responsibility
Medically reviewed content
Dr. Răzvan Anițaș
Consultant orthopaedic and trauma surgeon; PhD in medical sciences
Last editorial update: 22 August 2026
Medical sources used for patient information
First step
Consultation, diagnosis and an individual treatment recommendation
This information does not replace a consultation. Surgery is recommended only after the individual benefits, alternatives and risks have been assessed.