MSK MRI

Dislocation of a polyethylene insert Mechanism of Dislocation (DPI in TKA) Proposed Cause Atraumatic nature No clear cause identified Traumatic mechanism (insert dislocation) Repeated posteriorly directed compressive force on the polyethylene insert from the femur Biomechanical basis for dislocation During knee flexion, femoral tibial contact moves posteriorly, leading to anterior lift-off of th..

Polyethylene Wear Polyethylene components used in total knee arthroplasty (TKA) can experience wear on the articular surfaces due to abrasion and fatigue This wear generates polyethylene debris, which triggers an inflammatory response. Over time, this response can lead to osteolysis and loosening. Radiographic Findings of Polyethylene Wear Progressive joint space narrowing Sequential radiographs..