INJURIES TO THE POSTEROLATERAL ASPECT OF THE KNEE - ASSOCIATION OF ANATOMIC INJURY PATTERNS WITH CLINICAL INSTABILITY

Seventy-one consecutive patients with posterolateral knee injuries had clinical stability testing abnormalities documented prospectively, We compared these findings with the incidence and patterns of their inju ries documented at surgery, An abnormal reverse pivot shift test was a ssociated with injury to the fibular collateral ligament (P = 0.01), p opliteal components (P = 0.01), and midthird lateral capsular ligament (P = 0.02). An abnormal posterolateral external-rotation test at 30 d egrees of flexion was associated with injury to the fibular collateral ligament (P = 0.0001) and lateral gastrocnemius tendon (P = 0.01). An abnormal adduction test at 30 degrees of flexion was associated with injury to the posterior arcuate ligament (P = 0.02), The results of th is study should alert the clinician to the possibility of injury to a specific anatomic structure when the corresponding clinical stability test is abnormal. Because the fibular collateral ligament was injured in only 23% of the knees in this large series of patients, we recommen d that an injury to the fibular collateral ligament not be the sole de termining factor in making the diagnosis of posterolateral injuries, T he wide array of injuries to many individual anatomic components that we found indicates the complexity of injuries to the posterolateral as pect of the knee.