In the first episode of our “Sky Sport Doctor” column aired on Sky Sport we dealt with ACL injury. Dr. Francesco Della Villa, director of our Education and Research Department, was the first guest.
What is the famous “ACL”?
The ACL, or anterior cruciate ligament, is one of the knee ligaments that connects the femur (thigh bone) to the tibia (shin bone). It is called “cruciate” because it crosses with another ligament (the posterior cruciate ligament) right at the centre of the knee. It is not only a ligament but also a “sensor” that sends information to the brain about the knee’s position in space.
Why is the ACL so important?
The anterior cruciate ligament has the role of controlling certain knee movements, particularly those that move the tibia forward and those involving rotation. It is important in allowing the knee to feel safe and stable, both in daily movements and especially in sports. The ACL is part of a more complex system, where static structures (ligaments) and dynamic structures (muscles and the nervous system) work together to ensure the stability of the leg and knee.
Which sports have the highest risk of ACL ruptures?
The ACL can rupture when subjected to intense strain or during high-intensity movements. The sports with the highest risk of ACL injury are primarily multi-directional team sports, including soccer, basketball, rugby, American football, as well as volleyball and downhill skiing.
How does the ACL rupture?
Each sport has its own mechanisms, which can be divided into three main categories:
- Non-contact injuries: where injury occurs without external impact (these are the most common and most frequent among young athletes and females).
- Indirect contact injuries: where injury occurs following a push, typically around the torso.
- Direct contact injuries: involving direct contact with the injured knee (these are less frequent).
ACL ruptures typically happen during deceleration, changes of direction, and landing.
Why do soccer players suffer ACL injuries?
Soccer is a highly complex sport with continuous changes in intensity and interactions within a challenging physical and mental environment. This combination makes soccer particularly high-risk for ACL injuries. Some important points:
- Injuries are more common at the start of the match
- Around 70% involve defensive actions (typically pressing actions)
- Injuries are often caused by neuro-cognitive and mechanical perturbations
What are the key factors at the time of injury?
- Biomechanics: postural analysis at the time of injury
- All the weight on one leg (movements carrying 250-400 kg)
- Role of the torso
- Insufficient knee flexion
- Knee inward movement (the so-called “dynamic valgus knee”)
These are highly complex events that often also lead to damage in other parts of the knee.
How frequent are ACL ruptures?
La rottura del crociato non è un infortunio molto frequente, in un recente studio che stiamo portando avanti circa il 3% dei giovani calciatori subisce questo infortunio ogni stagione. Nelle squadre di Calcio professionistico invece ci si può attendere un infortunio ogni due stagioni.
Among active professional soccer players, approximately 10% have experienced an ACL injury.
Global data shows a worrying increase in these injuries among young people, which is a focus of concern for the entire sports medicine community. The risk increases in particular after the adolescent growth spurt.
Is it true that females have a higher risk of ACL rupture?
Females are about three times more likely to suffer an ACL injury compared to males. The reasons are varied, mainly biological, anatomical, and functional.
Can ACL injuries be prevented?
By studying the biomechanics at the time of injury, prevention programmes based on exercises have been developed. These “neuromotor training” exercises work on optimising posture. When applied correctly and consistently, they reduce non-contact ACL injuries by 67% in females (2/3 of injuries are prevented) and by 50% in all sportspeople.
Our approach, which we implement in dedicated areas, includes a movement analysis test to help the patient become aware of their movements and to personalise preventive exercises.
