Surgery
ACL Reconstruction
ACL reconstruction rebuilds a torn anterior cruciate ligament in the knee using a graft, to restore stability, often after a sports injury.
Quick answer
ACL Reconstruction: what it is, why it's done and what happens
ACL reconstruction replaces a torn anterior cruciate ligament — a key stabilising ligament in the knee — with a graft, usually taken from the patient’s own tendon, using keyhole (arthroscopic) surgery.
- Why it is done: It is used when a torn ACL causes the knee to give way, especially in active people or those who play sports involving twisting and pivoting, when the instability affects daily life or activity.
- What happens: Under general anaesthetic, the surgeon removes the damaged ligament and threads a graft into position through small keyhole incisions, securing it in the bone.
What it is
ACL reconstruction replaces a torn anterior cruciate ligament — a key stabilising ligament in the knee — with a graft, usually taken from the patient’s own tendon, using keyhole (arthroscopic) surgery.
Why it is done
It is used when a torn ACL causes the knee to give way, especially in active people or those who play sports involving twisting and pivoting, when the instability affects daily life or activity.
What happens
Under general anaesthetic, the surgeon removes the damaged ligament and threads a graft into position through small keyhole incisions, securing it in the bone. It usually takes 1–2 hours as a day case or short stay.
Recovery
A structured physiotherapy programme is central to recovery. Walking with support starts early, but return to sport typically takes around 9–12 months, depending on progress and the sport.
Good to know
Risks and things to consider
Risks include infection, stiffness, blood clots, graft failure and ongoing instability. Rehabilitation is demanding and vital; skipping it increases the risk of re-injury.
Education and reference only. This explains the procedure in general terms and is not medical advice. Your own care, risks and recovery will be explained by the team looking after you.
Answers
ACL Reconstruction: frequently asked questions
Do all ACL tears need surgery?
No. Some people, especially those who are less active or avoid pivoting sports, manage well with physiotherapy alone. Surgery is usually considered when instability affects daily life or sport.
When can I return to sport?
Return to pivoting sports usually takes around 9 to 12 months and depends on regaining strength, control and confidence through rehabilitation, not just on time passing.
Related
Other surgery
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — procedure and treatment guidance
- British Orthopaedic Association / relevant professional body
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