Taguchi Susumu, Namikawa Takashi, Ieguchi Makoto, Takaoka Kunio
Department of Orthopedic Surgery, Graduate School of Medicine, Osaka City University, Osaka City, Japan.
Clin Orthop Relat Res. 2007 Aug;461:162-9. doi: 10.1097/BLO.0b013e318059ae44.
Massive bone defects often are caused by radical resection of bone tumors. Reconstruction of the defect by reimplantation of the resected bone segment after it has been devitalized is advantageous because of its ability to match the size of the defect. In addition, this technique carries a low risk for local recurrence of the tumor, avoids immunologic reaction, and is low in cost. However, limited osteogenic potential of the devitalized bone often leads to delayed union, gradual resorption, and mechanical weakness of the reimplanted segment. We applied rhBMP-2 in a biodegradable polymer delivery system to the devitalized bone. Middiaphyseal bone defects were created by resection in rat femurs. The resected segments were autoclaved at 135 degrees C for 15 minutes, coated with a rhBMP-2-retaining paste on the outer surface, and then reimplanted into the defects. In a brief time, newly formed bone was seen on the surface of the devitalized bone. After 12 weeks, a solid bone mass encasing the dead bone segments was consistently formed and abundant new bone formation was visible in the segments as they were remodeled. The amount of new bone formed could be regulated by the amount of the rhBMP-2-retaining paste applied to the bone segments. This method presents a new approach for the reconstruction of bone defects.
巨大骨缺损通常由骨肿瘤的根治性切除引起。将切除的骨段失活后再植入以重建缺损具有优势，因为它能够匹配缺损的大小。此外，该技术肿瘤局部复发风险低，避免免疫反应，且成本低。然而，失活骨的成骨潜力有限，常导致延迟愈合、逐渐吸收以及再植入骨段的机械性薄弱。我们将rhBMP-2应用于可生物降解聚合物递送系统中处理失活骨。通过切除大鼠股骨中段制造骨缺损。切除的骨段在135℃高压灭菌15分钟，在外表面涂抹含rhBMP-2的糊剂，然后再植入缺损处。短时间内，在失活骨表面可见新形成的骨。12周后，始终形成包裹死骨段的坚实骨块，并且在骨段重塑过程中可见大量新骨形成。形成的新骨量可通过应用于骨段的含rhBMP-2糊剂的量来调节。该方法为骨缺损的重建提供了一种新途径。
