Wk 1, Case 4 - Review

Patient History

Hyper-extension dance injury 9 days ago. Pain in the popliteal area. Severe pain with straightening.

Findings
Menisci:

Medial Meniscus: Discoid meniscus (Images A-C) with abnormal oblique high signal extending from the body into the posterior horn, extending to part of the superior articular surface (Images D and E). Appearances are consistent with an upper surface (but predominantly closed intrameniscal) flap tear of the discoid meniscus. The tear measures 2-3cm in length from anterior to posterior.

Lateral Meniscus: Intact.

Ligaments: Anterior Cruciate Ligament: Complete full-thickness ACL tear. No passive anterior tibial translation.

Posterior Cruciate Ligament: Intact

Medial Collateral Ligament: Diffuse periligamentous edema surrounding the tibial collateral ligament with swelling and increased intrasubstance signal in the proximal tibial collateral ligament, consistent with an intermediate grade/grade 2 injury. Extension anteriorly into a high-grade tear involving the proximal/central medial patellofemoral ligament as described below.

Lateral Collateral Ligament: Subtle periligamentous edema surrounding the fibular collateral ligament, consistent with low-grade/grade 1 sprain.

Posterolateral Corner Structures: Intact

Posteromedial Corner Structures: Swollen/edematous, but intact, popliteal oblique and oblique popliteal ligaments. Markedly edematous/swollen posterior mensicocapsular junction suggesting a RAMP 1 injury.

Extensor Mechanism:

Patellar Tendon: Intact

Distal Quadriceps Tendon: Intact

Medial Patellofemoral Ligament: High-grade full-thickness tear involving the proximal medial patellofemoral ligament attachment at the adductor tubercle, adjacent to the proximal MCL. The tear extends into the anterior tibial collateral ligament as an intermediate grade injury as described above.

Medial and Lateral Patellar Retinacula: Diffusely edematous lax medial patellar retinaculum. Slightly thickened, tight lateral retinaculum.

Hoffa’s Fat Pad: Mild focal superolateral Hoffa’s fat pad edema.

Articulations:

Patellofemoral compartment: No trochlear or patellar dysplasia.

Medial Compartment: Pivot-shift pattern of osseous injury as described below.

Lateral compartment: Pivot-shift pattern of osseous injury as described below.

General:

Bones: Subchondral microtrabecular fracture with minimally depressed sulcus terminalis and surrounding lateral femoral condyle high-grade osteoedema. Posterolateral tibial microtrabecular contusion. Posteromedial tibial microtrabecular injury/contusion.

Effusion: Moderate-sized hemoserous suprapatellar effusion with reactive synovitis.

Baker’s Cyst: Small partially decompressed Baker’s cyst measuring a 2.8 x 1.8 x 0.5 cm with evidence for partial dehiscence. Small amount of extravasated fluid seen tracking superiorly, anterior to the origin of the medial gastrocnemius, between myofascial planes.

Loose Bodies: None.

Soft Tissues: Unremarkable.

Conclusion
Evidence for recent pivot-shift mechanism injury with the following:

1.ACL transection.
2.Intermediate-grade/grade 2 tibial collateral ligament sprain.
3.Full-thickness high-grade tear involving the proximal attachment of the medial patellofemoral ligament at the adductor tubercle. Tear extends into the adjacent tibial collateral ligament as an intermediate grade injury.
4.Discoid medial meniscus with a predominantly intrameniscal flap tear extending from the body into the posterior horn, with upper articular surface communication.
5.Torn posterior medial meniscocapsular ligaments (RAMP 1 lesion) and swollen posteromedial corner.
6.Pivot-shift pattern of osseous injury with: Minimally depressed sulcus terminalis; microtrabecular injury/contusions of the posterolateral and posteromedial tibia.
7.Low-grade/grade 1 fibular collateral ligament injury.
8.Moderate sized hemarthrosis.