Once the reduction of the metaphyseal segment is obtained, crossing 2.0-mm K-wires can provisionally maintain the reduction (Figure 6). Notably, these wires are often not adequate to maintain the reduction alone, and the longitudinal traction and flexion used to obtain the initial reduction must be maintained.
An external fixator or unicortical plates can augment this provisional reduction (Figure 6). To use an external fixator for this purpose, 2 to 3 anterior-to-posterior Schanz pins are placed in the shaft of the femur and the articular block. Typically, a proximal pin in the femoral shaft and an articular block pin are placed first. Sequential traction, manipulation, and clamp tightening helps the surgeon achieve anatomic length with relative control of rotation. An additional femoral shaft pin can be placed closer to the fracture site to improve control of the shaft of the femur.
Unicortical plates can also augment provisional fixation. The authors' preferred implants for this purpose are 2.7-mm reconstruction plates which are flexible and allow for some degree of contouring with application while minimizing the displacement of reduced fragments. The authors' preference is to place unicortical provisional plates laterally, where they will end up underneath the definitive plate because this minimizes the added "biologic cost" of periosteal stripping and plating in a second location. Anterior placement of provisional plates, for example, may require increased periosteal stripping and impose an added "biologic cost."
J Am Acad Orthop Surg. 2021;29(18):770-779. © 2021 American Academy of Orthopaedic Surgeons