Pazzaglia U E, Andrini L, Di Nucci A
Facoltà di Medicina e Chirurgia, Università di Brescia, Italy.
Int Orthop. 1997;21(4):267-73. doi: 10.1007/s002640050165.
Bone reaction to cement and to a cementless stem was studied in the rat femur with histological fluorescence and microangiographic techniques. Periosteal and endosteal apposition, and consequent remodelling, appeared as a reaction to reaming rather than caused by cement or a cementless stem. Every change in bone began with proliferation, progression and orientation of the vessels. Endosteal apposition was absent in cemented femurs because the entire medulla was occupied by the acrylic cement, but remodelling of the subendosteal cortex followed medullary revascularisation which was far advanced after 90 days. In cementless stems, endosteal apposition of primary woven bone and remodelling was the basis for bony ingrowth and anchorage through bony bridges. Our results suggest that the pattern of blood supply is relevant to the structural organisation of mature lamellar bone around the implant. Cemented stems have maximum anchorage and stability as soon as they are inserted, but this decreases with time as revascularisation occurs. Cementless stems can reach maximum integration later after insertion, and revascularisation is less critical because they usually do not fill the canal completely.
采用组织学荧光和微血管造影技术，在大鼠股骨中研究了骨对骨水泥和非骨水泥柄的反应。骨膜和骨内膜的附着以及随之而来的重塑，似乎是对扩髓的反应，而非由骨水泥或非骨水泥柄引起。骨的每一处变化都始于血管的增殖、延伸和定向。骨水泥固定的股骨中不存在骨内膜附着，因为整个髓腔被丙烯酸骨水泥占据，但骨内膜下皮质的重塑跟随髓腔再血管化，90天后这种再血管化进展显著。在非骨水泥柄中，初级编织骨的骨内膜附着和重塑是通过骨桥实现骨长入和锚固的基础。我们的结果表明，血液供应模式与植入物周围成熟板层骨的结构组织相关。骨水泥柄一旦插入就具有最大的锚固力和稳定性，但随着再血管化的发生，这种稳定性会随时间降低。非骨水泥柄在插入后较晚才能达到最大整合度，而且再血管化不太关键，因为它们通常不会完全填满髓腔。
