Jain R, Podworny N, Hearn T, Richards R R, Schemitsch E H
Musculoskeletal Research Laboratory, St. Michael's Hospital, Toronto, Canada.
J Trauma. 1998 Jan;44(1):193-7. doi: 10.1097/00005373-199801000-00028.
The biomechanical properties of plates depend on their geometries and elastic moduli. The low contact-dynamic compression plate (LC-DCP) with relieved undersurfaces is a modification of the dynamic compression plate (DCP). Little attention has been directed toward comparison of the biomechanical properties of the LC-DCP and the DCP. This study compared the stiffness and strength of bone-plate constructs using plates of various designs and materials for fixation of radial osteotomies. In 20 matched pairs of canine radii, midshaft transverse osteotomies were created and fixed with 3.5-mm eight-hole plates on the volar surface. In 10 pairs, stainless-steel LC-DCPs and stainless-steel DCPs were applied. In the other 10 pairs, stainless-steel LC-DCPs and titanium LC-DCPs were placed. Bending and torsional stiffness were determined. The plates were removed, and a 5-mm gap was created at the osteotomy site. The plates were reapplied to the bones with the interfragmental gap. Stiffness and yield point in the anteroposterior direction were determined.
In the absence of a bone gap, no statistically significant differences in construct stiffness were seen between the paired groups. In the presence of a gap, the stainless-steel LC-DCP construct was stiffer than the titanium LC-DCP construct (p = 0.02), and the DCP construct was stiffer than the LC-DCP construct (p = 0.002). The yield point of the DCP-bone construct was 59% greater than that of the stainless-steel LC-DCP construct (p = 0.02). However, the yield points of the titanium and stainless-steel LC-DCP-constructs were similar (p = 0.35).
The similar results between constructs in the absence of a gap indicate that plate design and material properties may be less significant for achieving adequate stability after plate fixation of simple fractures. The use of the stiffer dynamic compression plate may be advantageous when maximum stability is required, such as with comminution or bone loss.
钢板的生物力学特性取决于其几何形状和弹性模量。下表面有减压设计的低接触动力加压钢板（LC-DCP）是动力加压钢板（DCP）的一种改良形式。很少有人关注LC-DCP和DCP生物力学特性的比较。本研究比较了使用不同设计和材料的钢板固定桡骨截骨术时骨-钢板结构的刚度和强度。在20对匹配的犬桡骨中，制作中段横行截骨并在掌侧用3.5毫米八孔钢板固定。10对使用不锈钢LC-DCP和不锈钢DCP。另外10对使用不锈钢LC-DCP和钛LC-DCP。测定弯曲和扭转刚度。取出钢板，在截骨部位制造5毫米的间隙。将钢板重新应用于有骨折块间间隙的骨上。测定前后方向的刚度和屈服点。
在没有骨间隙的情况下，配对组之间的结构刚度没有统计学上的显著差异。在有间隙的情况下，不锈钢LC-DCP结构比钛LC-DCP结构更硬（p = 0.02），DCP结构比LC-DCP结构更硬（p = 0.002）。DCP-骨结构的屈服点比不锈钢LC-DCP结构高59%（p = 0.02）。然而，钛和不锈钢LC-DCP结构的屈服点相似（p = 0.35）。
在没有间隙的情况下结构之间的相似结果表明，对于简单骨折钢板固定后实现足够的稳定性，钢板设计和材料特性可能不太重要。当需要最大稳定性时，如粉碎性骨折或骨缺损，使用更硬的动力加压钢板可能是有利的。
