There is a lack of literature evaluating in detail the epidemiology of associated injuries in combination with anterior cruciate ligament (ACL) tears.
To define in detail the prevalence of associated injuries in patients with ACL tears.
Data from a national multicentre longitudinal cohort ACL study were analysed. Only patients who underwent magnetic resonance imaging (MRI) were included in this study. All MRI scans were reviewed by an orthopaedic knee surgeon and a musculoskeletal radiologist. The mean time from ACL injury to MRI was 19.6 ± 15.2 days. MRI examinations were performed using a 1.5 (n = 115) or 3.0 (n = 138) Tesla scanner. The images were acquired in three planes (sagittal, axial and coronal) using T1-weighted, T2-weighted and proton-density (PD) fat saturation sequences. Injuries to the medial meniscus (MM), lateral meniscus (LM), medial collateral ligament (MCL), lateral collateral ligament (LCL), cartilage, and the presence of a Segond fracture were recorded. Injuries to the MCL or LCL were defined as partial rupture/discontinuity with some preserved fibres or complete disruption. Isolated deep MCL injuries were defined as tears of the meniscofemoral and/or meniscotibial ligament with intact superficial MCL on axial images. The presence and location of bone bruising was also evaluated. Bone bruising in the posteromedial tibial (PMT) plateau and medial femoral condyle (MFC) was recorded. Pivot-shift-type bone bruising was defined as the presence of bone marrow oedema in the posterior aspect of the lateral tibial plateau and the midportion of the lateral femoral condyle (LFC). Finally, the presence of a fracture of the posterolateral tibial plateau and an LFC impaction, defined as an osteochondral depression with an intact or disrupted articular surface, was recorded.
A total of 253 patients (52.2% males) with a mean age of 25.4±7.1 years were included. An LCL injury was present in 2.4% of the patients, whereas an MCL injury (both superficial and deep MCL) in 16.6%. Isolated deep MCL injuries were present in 25.5% of the patients. Significantly more MM than LM injuries were found (61.4% vs. 27.2% respectively), although MM injures included ramp lesions (39.5%). Cartilage injuries were diagnosed in 15.0% of the patients, whereas a posterolateral tibial plateau fracture and a Segond fracture were found in 4.7% and 7.5% of the cases respectively. An LFC impaction was found in 45.7% of the patients. Finally, pivot shift bone bruising, PMT bone bruising and MFC bone bruising were found in 72.3%, 39.5% and 19.0% of the patients respectively.
The prevalence of injuries associated with ACL tears was very high. This study provides a detailed overview of the possible associated injuries in patients with ACL tears. These findings might be helpful for radiologists and orthopaedic surgeons for the treatment of patients with ACL tears.