Anterior cruciate ligament

Looks like

A strong band inside the knee, crossing from the back of the thigh bone to the front of the shinbone.

What it does

Stops the shinbone sliding forward and steadies the knee in twisting and landing.

Keeping it well

Torn in pivoting sports: a pop, fast swelling and a knee that gives way. Landing and strength training lower the risk, and women tear it more often.

Related conditions

• ACL & meniscus injury
• Baker's (popliteal) cyst
• Chronic venous insufficiency
• Gout
• Growing pains
• Haemophilia & bleeding disorders
• Juvenile idiopathic arthritis
• Lyme disease
• Lymphatic filariasis (elephantiasis)
• Lymphoedema
• Marfan syndrome & connective tissue disorders
• Osteoarthritis
• Pseudogout (calcium pyrophosphate disease)
• Psoriatic arthritis
• Reactive arthritis
• Restless legs syndrome
• Rheumatic fever & rheumatic heart disease
• Rheumatoid arthritis
• Septic arthritis
• Systemic lupus erythematosus
• Temporomandibular joint disorder
• Varicose veins