Anterior Cruciate Ligament Injuries

Anterior Cruciate Ligament Injuries

The anterior cruciate ligament (ACL) is an important ligament that lies within the knee joint and stops the shin bone moving forwards from under the thigh bone. If it gets damaged then the knee may become unstable and give way or collapse especially in movements that involve turning on a flexed knee.

The ACL usually tears when a sportsperson suddenly changes direction when running such as when playing rugby, football or netball and most commonly there is no external contact at the time. As it tears the patient often hears a popping sound, the knee collapses and then swells up within a few hours. With rest the swelling will settle and the knee becomes more comfortable, but then when sport is resumed the same thing happens again when it gives way.

Patients who have damaged their ACLs need assessment and those that have repeated episodes of instability or who wish to return to active sports may benefit from a reconstruction of the ligament. However 20% – 30% of patients with torn ACLs can return to their day to day activities without major problems.

Unfortunately when the ACL goes there is often other damage to the knee at the same time such as a torn meniscus or joint surface damage which also may require treatment.

Torn Anterior Cruciate