Introduction
The presence of Bone Bruises (BB), especially in the lateral compartment of the knee, is common finding in the context of Anterior Cruciate Ligament (ACL) injury. However, different patterns has been described and a precise correlation with mechanism of ACL injury has never been determined with precision
Material And Methods
Fifteen professional football (soccer) players that sustained ACL injury while playing during an official match of First League Championship were included in the study. The video of injury was obtained from the Television broadcast. Knee Magnetic Resonance (MRI) was obtained within 7 days from the injury. BB and meniscal lesions were analyzed on MRI, while a video-analysis of mechanisms of ACL injury and injury dynamic were assessed from the videos.
Results
The most common pattern of BB (Fig A,B), present in 8 cases (53%) was a femoral BB >5 mm in the central portion of the lateral femoral condyle and in the posterior portion of the lateral tibial plateau. In all these cases, the injury occurred with single-leg load during a pivoting maneuver while changing direction during pressing (33%), dribbling (7%), goalkeeping (7%) or in response of being being tackled on the upper body (7%). All these injuries occurred without direct contact, high horizontal speed and with abduced hip.
Other patterns (Fig. C) included BB only in tibia (20%), tibia and femur BB <5 mm (7%) or no BB (20%). In these cases, injury occurred due to direct contact (20%), recovery balance after kicking (13%) or jumping (7%), and while tackling (7%).
Conclusions
A characteristic and well-defined Bone Bruise pattern in both tibia and femur was identified in professional footballers' ACL injuries (without direct contact and in single-leg loading) while pivoting and trying to perform a sudden change of direction.