Distal Femoral Deformity Correction Using MAC

Distal femoral deformities are challenging and can be treated in a variety of different ways (1). For skeletally immature patients, guided growth plates can be used to correct deformities, especially in the coronal plane (2). When there is a complex deformity present especially when there is a need to lengthen the femur, then an external fixator is usually required. The MAC (multiaxial correction) device allows correction of displacement and angulation in all three planes and also allows the bone to be lengthened. Preoperative planning is essential to define the different parameters of the deformity. This device is placed laterally on the femur and is attached with hydroxyapatite-coated half pins proximal and distal to the proposed osteotomy site. Deformity correction is usually started by the patient at 5–7 days post-application. Removal of the external fixator can only occur once a satisfactory consolidation of the regenerate bone has been achieved.