Objective: Reconstruction and long-term stabilization of segmental diaphyseal bone defects of the humerus, femur, and tibia.
Indications: Segmental bone defects due to aggressive benign or primary malignant bone tumors, trauma, pathological fractures, osteomyelitis, or failed osteosynthesis.
Contraindications: Acute or chronic local infections, large metadiaphyseal bone defects preventing adequate anchorage of the prosthesis, very short life expectancy (<3 months).
Surgical technique: Exposure and resection of the bony defect according to the preoperative planning. Reaming of the intramedullary canals proximally and distally followed by implantation of the stems (cemented or noncemented). Reducing sleeves can be used to bridge the difference in diameter between the nail and the spacer. Mounting of the spacer half shell with the threaded holes from underneath after adjusting for alignment and rotation. Assembling of the other half shell by guided pins to ensure proper alignment. Tightening of the clamping screws using a torque screwdriver. Connection of two spacers is possible.
Postoperative management: Active physiotherapy and full weight bearing; antibiotic prophylaxis.
Results: The results of 14 consecutive patients treated with 15 modular intercalary endoprostheses (Osteobridge™, Merete, Berlin, Germany) between January 2007 and January 2012 with a mean follow up of 24 ± 12 months (range 12-51 months) were evaluated retrospectively. One patient had a primary malignant bone tumor, while all the other patients underwent resection for metastatic disease. The mean age at surgery was 65.9 ± 15.7 years (range 25-83 years). The mean diaphyseal reconstruction length was 110 ± 50 mm (range 50-190 mm). Three patients (20%) required revision of the distal stem due to aseptic loosening. Evaluation of the functional outcome using the MSTS score by Enneking revealed 3 very good (22%), 7 good (50%), 4 fair (28%), and no poor results.
Keywords: Bone diseases; Bone neoplasms; Diaphyses replacement; Neoplasm metastasis; Prostheses and implants.