Current Concepts of Posterolateral Corner Injuries of the Knee

Abstract

The number of posterolateral corner (PLC) injury patients has risen owing to the increased motor vehicle accidents and sports activities. Careful examination is required because this injury is easy to overlook and may lead to chronic instability. The purpose of this article is to review the anatomy, biomechanics, diagnosis, classification and, treatment of PLC injuries and summarize the recent literatures regarding the treatment outcomes.

Keywords: Diagnosis; Instability; Knee; Treatment.

Fig. 1

Anatomy of the posterolateral corner. A: lateral gastrocnemius tendon, B: popliteofibular ligament, C: popliteus muscle and ligament, D: lateral collateral ligament.

Fig. 2

The left illustration shows normal gait during the loading-response phase of gait. The right illustration shows varus thrust gait during weight bearing on the injured knee.

Fig. 3

Dial test performed with the patient in prone position with the knees flexed to 90° and 30°. The knees are flexed to 90° in the left photograph and 30° in the right photograph.

Fig. 4

Varus stress radiographs demonstrating increased opening at the lateral joint line. The right radiograph shows a 14 mm opening (arrow) in the injured knee.

Fig. 5

Sagittal and coronal magnetic resonance imaging scans of a posterolateral corner injury in the left knee. (A) Discontinuity of the posterior cruciate ligament (arrow head) is seen in the sagittal view. (B) High signal on the lateral collateral ligament (arrow) is seen in the coronal view.

Fig. 6

Lateral joint opening (drive-through sign) observed in arthroscopy.

Fig. 7

Algorithm of posterolateral corner treatment according to the chronic or acute injury. PFL: popliteofibular ligament, LCL: lateral collateral ligament.

Fig. 8

Radiographs showing the fixation points of allograft through the fibular tunnel as described in the illustration (modified larson technique). A, B: femoral tunnel. Anatomical insertions of LCL and popliteus tendon at the lateral femoral condyle aimed toward the flare of the medial femoral epicondyle, C: fibular tunnel. Starting point is set at the distal anterolateral portion of the fibular head (insertion of LCL) exiting proximal posteromedial portion of the fibular head (insertion of PFL). LCL: lateral collateral ligament, PFL: popliteofibular ligament.

Fig. 9

Achilles tendon was split into two bundles and anatomic double bundle reconstruction was performed.