Patient History
17-year-old male with constant moderate left knee pain, difficulty walking, weakness and swelling following an injury playing football 3 days prior.
Findings
Menisci:
Medial Meniscus: Intact.
Lateral Meniscus: Intact.
Ligaments:
Anterior Cruciate Ligament: Intact.
Posterior Cruciate Ligament: Complete full-thickness midsubstance to proximal PCL tear, with associated ligamentous laxity, fiber discontinuity and marked increased intrasubstance signal.
Medial Collateral Ligament: Extensive periligamentous edema involving layer I or the “crus layer” surrounding an intact tibial collateral ligament, consistent with low-grade/grade 1 sprain.
Lateral Collateral Ligament: Intact.
Posterolateral Corner Structures: Posterolateral corner injury with swollen sprained popliteofibular ligament and arcuate ligament. Diffuse periligamentous edema. Low to intermediate grade strain at the popliteus myotendinous junction with diffuse edema involving at least 50 percent of the cross-section and extending approximately 5 cm in length. Posterior capsule thickened and swollen.
Posteromedial Corner Structures: Intact.
Extensor Mechanism:
Patellar Tendon: Intact.
Distal Quadriceps Tendon: Intact.
Medial Patellofemoral Ligament: Intact.
Medial and Lateral Patellar Retinacula: Intact.
Hoffa’s Fat Pad: Unremarkable.
Articulations:
Patellofemoral Compartment: Unremarkable.
Medial Compartment: Unremarkable.
Lateral Compartment: Unremarkable.
General:
Bones: Minimally impacted fracture of the anterolateral tibial plateau, with high-grade osteoedema. Small microtrabecular injury of the anterior aspect of the medial tibial plateau. Otherwise unremarkable.
Effusion: Moderate-sized suprapatellar effusion.
Baker’s Cyst: None.
Loose Bodies: None.
Soft tissue and neurovascular structures: Unremarkable.
Conclusion
Combination of findings consistent with a hyperextension injury, including:
1.High grade, full thickness mid substance PCL tear (PCL transection).
2.Grade 1-2 sprain medial collateral ligament.
3.Minimally impacted fracture of anterior medial tibial plateau and mictotrabecular fracture of the lateral tibial plateau. Hyperextension injury.
4.Injured posterolateral corner with sprained popliteofibular and arcuate ligaments and strained popliteus myotendinous junction sprain. Capsular injury.
