Distal femur replacement is useful in complex total knee arthroplasty revisions.

UNLABELLED: Revision total knee arthroplasty can be considerably more difficult in cases involving severe bone loss, complete absence of collateral ligaments, and persistent periprosthetic supracondylar femoral fractures. Modular segmental endoprosthetic distal femur replacement is a limb salvage option when other surgical options are unfeasible. The clinical performance of rotating hinge knee prostheses has greatly improved with the evolution of second and third generation designs. The increased freedom of rotation decreases the prosthetic bone stresses and the longevity. While designs have improved, the prostheses still do not match the function and longevity of condylar components with approximately a 90% survivorship at 20 years. The modular endoprosthesis rotating hinge knee prosthesis is useful for total knee arthroplasty revision in patients with inadequate bone stock, ligamentous instability, or difficult supracondylar femur fractures, especially in low demand elderly patients. LEVEL OF EVIDENCE: Therapeutic study, level V (expert opinion). See Guidelines for Authors for a complete description of levels of evidence.