From the Guidelines
Suspected concomitant injuries with an acute medial collateral ligament (MCL) full-grade tear include ACL tears, meniscal injuries, and medial compartment cartilage damage, which can be accurately diagnosed using MRI, as it has been shown to be a valuable tool in the treatment decision-making process, allowing earlier surgical intervention by obtaining a more accurate diagnosis 1. When a patient presents with a complete MCL tear, clinicians should have a high index of suspicion for associated cruciate ligament injuries, particularly to the anterior cruciate ligament (ACL), which occurs due to similar injury mechanisms involving valgus force combined with rotational stress. Some key points to consider in the diagnosis of concomitant injuries include:
- Meniscal tears, especially to the medial meniscus, are also common accompanying injuries as the same forces that damage the MCL can disrupt the meniscus.
- Bone contusions or bruising of the lateral femoral condyle and lateral tibial plateau may be present due to the compressive forces on the lateral compartment during the valgus stress.
- In more severe injuries, particularly those involving high-energy trauma, patients may also have sustained damage to the posteromedial corner structures including the posterior oblique ligament, semimembranosus tendon, or even the posterior cruciate ligament (PCL).
- Thorough clinical examination including assessment of all knee ligaments and advanced imaging such as MRI is essential to identify these associated injuries, as they significantly impact treatment decisions and rehabilitation protocols, with MRI having been shown to shorten the diagnostic completion workup, reduce the number of additional diagnostic procedures, and improve quality of life in the first 6 weeks 1. The use of MRI is particularly important in the diagnosis of concomitant injuries, as it can detect the patterns and severity of bone marrow contusions, predict associated soft-tissue injuries, and diagnose anterolateral ligament injuries, which are frequently associated with ACL injuries and anterolateral knee instability 1.
From the Research
Suspected Concomitant Injuries with Acute Medial Collateral Ligament (MCL) Full-Grade Tear
- The suspected concomitant injuries with an acute MCL full-grade tear include:
- Lateral meniscal injuries 2
- Lateral collateral ligament (LCL) injuries 2
- Bone bruises in the lateral and medial compartments of the knee 2, 3
- Meniscal ramp lesions 4
- Medial meniscal tears 4, 5
- Chondral lesions 3
- Pivot-shift-type bone bruising 4
- Posteromedial tibial (PMT) bone bruising 4
- Lateral femoral condyle (LFC) impaction 4
- Segond fracture 4
- Medial femoral condyle bone marrow edema 5
Association with MCL Injuries
- MCL injuries are often associated with concomitant intra- and extra-articular injuries, including lateral meniscal injuries and bone bruises in the lateral and medial compartments of the knee 2, 3
- The presence of bone bruises involving both the lateral and medial compartments of the knee is significantly associated with MCL injuries 2
- MCL injuries can also be associated with medial meniscal tears, particularly posterior horn medial meniscal tears 5
Mechanism of Injury
- Contact sports and valgus injuries with external rotation can lead to MCL tears and concomitant injuries, such as ACL tears and meniscal injuries 6
- The mechanism of injury can influence the type and severity of concomitant injuries, with contact sports and valgus injuries being more likely to result in MCL tears and associated injuries 6