Learning objectives
To review the anatomic structures of the posterolateral corner (PLC) of the knee.
To approach the possible injuries to the structures of the PLC of the knee and the main patterns of injury.
To review the role of imaging in the PLC injuries.
Background
The anatomy of the PLC is complex and these structures are primarily responsible for resisting varus angulation.
Although they are not frequent,
untreated PCL injuries can lead to chronic knee instability,
cartilage damage,
poor outcome to anterior cruciate and posterior cruciate ligament reconstructions and chronic pain.
The posterolateral corner (PLC) has been regarded as of difficult evaluation owing to the variable and complex anatomy allied to the inconsistent terminology used in the literature to describe the structures in this region.
Injuries to the PLC structures...
Imaging findings OR Procedure Details
Lateral Colateral Ligament
The LCL is the primary static restraint to varus stress on the knee and has a secondary role of limiting external rotation,
particularly during the early phase of flexion.LaPrade and Terry evaluated 71 patients presenting with a PLC injury and signs of instability and at surgery found an injured LCL in 23 % of the knees.
The LCL is an extracapsular structure,
originates from a small osseous depression proximal and posterior to the lateral femoral epicondyle and
immediately anterior to the femoral...
Conclusion
The diagnosis of acute PLC injuries is based on the clinical presentation.
However,
because the physical findings are often dominated by the associated injurires,
MRI has a major role in uncovering PLC injuries.
This is critical because they often require surgical reconstruction and this leads to improved long-term outcomes and the prevention of chronic knee instability and damage.
References
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H G.
Unraveling the Posterolateral Corner of the Knee.
RadioGraphics 2016;36;1776-1791
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Rasmussen O,
Ovesen J,
Andersen K.
Rotatory instabilityof cadaver knees after transection of collateral ligamentsand capsule.
Arch Orthop Trauma Surg 1984;103(3):165–169.
3.
Nielsen S,
Ovesen J,
Rasmussen O.
The posterior cruciateligament and rotatory knee instability: an experimental study.Arch Orthop Trauma Surg 1985;104(1):53–56.
4.
Seebacher JR,
Inglis AE,
Marshall JL,
Warren RF.
The structureof the posterolateral aspect of the knee.
J Bone Joint Surg Am1982;64(4):536–541.
5.
Watanabe Y,
Moriya H,
Takahashi K,...