Calhoun J H, Li F, Bauford W L, Lehman T, Ledbetter B R, Lowery R
Division of Orthopaedic Surgery, University of Texas Medical Branch, Galveston.
Bull Hosp Jt Dis. 1992 Summer;52(1):21-6.
The success of the Ilizarov technique is due to the combination of the biomechanics of its external fixator and the biology of distraction osteogenesis. The stability and stiffness of the conventional Ilizarov fixator is attributed to its use of a K-wire cross structure. The disadvantages of this structure include pain, and possible neurologic and vascular injuries when the wires are introduced into crucial neurovascular areas, as well as increased frame complexity and construction. Reducing the number of wires decreases these problems, but also decreases the stiffness of the system. Hybrid (wire and half-pins) Ilizarov fixators and half-pin fixators are also being used in an attempt to alleviate these problems. Half-pins have been described by Fleming et al. and Green as causing minimal transfixation of the surrounding soft tissues and capable of and being inserted into anatomically safe areas. The stiffnesses of the hybrid systems have not been measured. This study reports on the stiffness of different wire and half-pin systems that were biomechanically tested in axial loading, anterior-posterior bending, medial-lateral bending, and torsional loading. The results demonstrated that the conventional Ilizarov fixator with wires possesses a high axial stiffness, whereas the fixator with half-pins possesses higher stiffness under bending and torsional loads. To obtain adequate stability, the use of hybrid Ilizarov frames with one wire and two or more half-pins (5 or 6 mm in diameter), or larger half-pin frames (5 or 6 mm) with three pins is recommended.
伊里扎洛夫技术的成功得益于其外固定器的生物力学与牵张成骨生物学的结合。传统伊里扎洛夫固定器的稳定性和刚度归因于其使用的克氏针交叉结构。这种结构的缺点包括疼痛，当克氏针插入关键神经血管区域时可能导致神经和血管损伤，以及增加框架的复杂性和构建难度。减少克氏针数量可减少这些问题，但也会降低系统的刚度。混合式（克氏针和半针）伊里扎洛夫固定器和半针固定器也被用于试图缓解这些问题。弗莱明等人和格林描述半针对周围软组织的贯穿损伤最小，能够插入解剖学上安全的区域。尚未对半针混合系统的刚度进行测量。本研究报告了在轴向加载、前后弯曲、内外侧弯曲和扭转加载下进行生物力学测试的不同克氏针和半针系统的刚度。结果表明，带克氏针的传统伊里扎洛夫固定器具有较高的轴向刚度，而带半针的固定器在弯曲和扭转载荷下具有较高的刚度。为获得足够的稳定性，建议使用带有一根克氏针和两根或更多半针（直径5或6毫米）的混合式伊里扎洛夫框架或带有三根半针的更大半针框架（直径5或6毫米）。
