First application of segmental trabecular metal cones in a custom-made revision tumor prosthesis of the knee: A technical note.

Background: Tumor prostheses are established as a standard procedure in tumors of the lower extremities. Septic and aseptic loosening remains the main reason for the failure of tumor prostheses. Due to bone defects, the possibilities of anchoring revision prostheses are limited. Trabecular metal cones are established in prosthetic revision surgery. However, the use of segmental trabecular metal cones in a custom-made tumor revision prosthesis has not yet been described.

Objective: A 58-year-old patient, who initially received a resection of the distal femur and reconstruction with a tumor prosthesis due to chondrosarcoma, attended our clinic. Because of aseptic loosening of this tumor prosthesis, revision surgery was indicated.

Methods: On account of huge bone defects, a reconstruction using a modular standard prosthesis was not possible. In order to prevent further resection of the bone and not replace the total femur, a custom-made revision tumor prosthesis was implanted.

Results: After preoperative planning and explantation of the loosened prosthesis, a partially cemented custom-made revision tumor prosthesis was successfully implanted using a Revitan® Curved revision stem with a custom-made Revitan® -Taperadapter and a custom-made segmental trabecular metal cone connected to a custom-made titanium segmental distal femur and a Zimmer® NexGen® RH Knee Tibia with a straight stem (Zimmer, Inc., USA).

Conclusions: The application of segmental trabecular metal in a custom-made revision tumor prosthesis offers a new option to the previously existing treatment strategies.