A Stronger Construct for Manipulating Osteoporotic Bone Fragments in a Distal Femur Fracture Model
Distal femur fractures account for 6% of all femur fractures and most often involve young patients and the elderly. In the elderly, osteoporotic bone poses a significant surgical challenge as there is an increased risk of bone failure or fracture as it is manipulated to restore length, alignment, and rotation. The following surgical technique addresses the challenges posed by osteoporotic bone in the repair of distal femur fractures with a sagittal plane deformity. A parapatellar approach to the femur is used and the articular surface of the condyle is reconstructed with the use of compression screws to achieve anatomic fixation. The screws must be bicortical and ≥5 mm apart in the sagittal plane. Following reconstruction of the articular block, a 4-mm Schanz pin is unicortically placed between the 2 bicortical screws in an anterior to posterior direction on the condylar segment. The Schanz pin is then levered up to correct the sagittal plane deformity. This creates a stronger lever arm construct that can be used to reduce the osteoporotic distal bone fragment with less risk of Schanz pin wallowing out or even cutout. This is moreso important as the Schanz pin is placed unicortically because of the proximity of the popliteal artery posterior to the condyle with the knee in extension. With correction of the sagittal plane deformity, the articular block and diaphyseal segment are reduced using a femoral plate.