anatomy/acl·Tendon / ligament
Anterior cruciate ligament
Ligamentum cruciatum anterius
The ligament deep in the knee that stops the shin bone sliding forward. It often tears during landings and changes of direction.
// Structure & location
Inside the knee joint lie two cruciate ligaments that cross each other. The anterior one runs from the front of the tibial plateau diagonally back and up to the femur. The posterior cruciate ligament runs the opposite way. The medial and lateral collateral ligaments and the menisci also secure the knee.
// Function
The ACL stops the tibia from sliding forward relative to the femur and provides stability during rotation. According to OpenStax, the knee is a hinge joint that, besides bending and straightening, can only rotate slightly when bent.
// For training & sport
- Most injuries happen without contact with an opponent, for example when landing or changing direction with the knee caving inwards.
- In a meta-analysis, prevention programmes with jumping, landing, strength and balance exercises halved the risk of ACL injuries. In women, non-contact injuries even fell by two thirds (Webster & Hewett, 2018).
- For men, the data in this analysis were insufficient for a clear conclusion.
// Good to know
Female athletes tear their ACL considerably more often than male athletes in the same sports, which is why most prevention studies focus on women.
// Sources
- LehrbuchOpenStax – Anatomy and Physiology 2e, 9.6 Anatomy of Selected Synovial Joints ↗
- Meta-Analyse 2018Webster & Hewett – Meta-analysis of meta-analyses of ACL injury reduction training programs (J Orthop Res) ↗
last reviewed: 2026-11-14