NORMAL AND PATHOLOGICAL ASPECTS OF THE PO STEROLATERAL CORNER (PLG) OF THE KNEE

The purpose of the study is to compare normal PLC anatomy and its MRI appearance, with the various lesions observed in MRI, from the simple popliteus tendinous contusion to the complete PLC rupture. For this sp ecific work on PLC lesions, we selected 61 examinations among the trau matic knees explored during the last 3 years. Surgical correlation is obtained for the 61 patients. MRI examinations are performed on a 0.5 T. unit with gradient echo T1, T1 and T1 GD-DOTA IV. Normal PLC anatom y is compared to the dissection of 4 anatomic subjects, Normal MRI sli ces are evaluated with this reference analysis The principle anatomica l structures of the PLC include the lateral collateral ligament, the p opliteus tendon, the arcuate ligament, the fabello fibular ligament, t he posterolateral condylar capsule, and the posterior horn of the late ral meniscus. Surgical findings confirm PLC lesion for 58 patients wit h 3 false positive. Diagnosis of these lesions is important because ch ronical posterolateral laxity is secondary to the destabilisation of l ateral condyle, Unrecognised and untreated posterolateral instability may result in failure of ACL reconstruction. When clinical tests are d oubtful or complex, or the examination very painful, MRI evaluates com pletely the traumatic knee and particularly the PLC.