Willis Andrew A, Kutsumi Keiji, Zobitz Mark E, Cooney William P
Tri-County Orthopaedics and Sports Medicine, 160 East Hanover Avenue, Morristown, NJ 07962, USA.
J Bone Joint Surg Am. 2006 Nov;88(11):2411-7. doi: 10.2106/JBJS.E.00946.
Volar plate fixation with use of either a locking plate or a neutralization plate has become increasingly popular among surgeons for the treatment of dorsally comminuted extra-articular distal radial fractures. The purpose of the present study was to compare the relative stability of five distal radial plates (four volar and one dorsal), all of which are commonly used for the treatment of dorsally comminuted extra-articular distal radial fractures, under loading conditions simulating the physiologic forces that are experienced during early active rehabilitation.
With use of a previously validated Sawbones fracture model, a dorsally comminuted extra-articular distal radial fracture was created. The fracture fixation stability of four volar plates (an AO T-plate, an AO 3.5-mm small-fragment plate, an AO 3.5-mm small-fragment locking plate, and the Hand Innovations DVR locking plate) were compared under axial compression loading and dorsal and volar bending simulating the in vivo stresses that are generated at the fracture site during early unopposed active motion of the wrist and digits. A single dorsal plate (an AO pi plate) was used for comparison, with and without simulated volar cortical comminution. The construct stiffness was measured to assess the resistance to fracture gap motion, and comparisons were made among the implants.
The volar AO locking and DVR plates had greater resistance to fracture gap motion (greater stiffness) compared with the volar AO nonlocking and AO T-plates under axial and dorsal loading conditions (p < 0.01), with no significant difference between the AO volar locking and DVR plates. The volar AO locking plate had greater resistance to fracture gap motion than did the volar AO nonlocking plate under axial loading and dorsal bending forces (p < 0.01). The dorsal pi plate had the greatest resistance to fracture gap motion under axial loading and volar and dorsal bending forces (p < 0.01). However, the pi plate was significantly less stable to axial load and dorsal bending forces when the volar cortex was comminuted (p < 0.01).
In this model of dorsally comminuted extra-articular distal radial fractures, dorsal pi-plate fixation demonstrated better resistance to fracture gap motion than did the four types of volar plate fixation. The AO volar locking and DVR plates conferred the greatest resistance to fracture gap motion among the four volar plates tested. Volar locking technology conferred a significant increase in resistance to fracture gap motion as compared with nonlocking plate technology.
使用锁定钢板或中和钢板进行掌侧钢板固定，在外科医生治疗桡骨远端背侧粉碎性关节外骨折中越来越普遍。本研究的目的是比较五种常用的桡骨远端钢板（四种掌侧钢板和一种背侧钢板）在模拟早期主动康复过程中所承受生理力的加载条件下的相对稳定性，这些钢板均常用于治疗桡骨远端背侧粉碎性关节外骨折。
使用先前验证过的Sawbones骨折模型制造桡骨远端背侧粉碎性关节外骨折。在轴向压缩加载以及模拟手腕和手指早期无对抗主动运动时骨折部位产生的体内应力的背侧和掌侧弯曲情况下，比较四种掌侧钢板（AO T形钢板、AO 3.5毫米小型碎片钢板、AO 3.5毫米小型碎片锁定钢板和手部创新DVR锁定钢板）的骨折固定稳定性。使用单个背侧钢板（AO π形钢板）进行比较，包括有和没有模拟掌侧皮质粉碎的情况。测量结构刚度以评估对骨折间隙移动的抵抗力，并在植入物之间进行比较。
在轴向和背侧加载条件下，与掌侧AO非锁定钢板和AO T形钢板相比，掌侧AO锁定钢板和DVR钢板对骨折间隙移动的抵抗力更大（刚度更大）（p < 0.01），AO掌侧锁定钢板和DVR钢板之间无显著差异。在轴向加载和背侧弯曲力作用下，掌侧AO锁定钢板比掌侧AO非锁定钢板对骨折间隙移动的抵抗力更大（p < 0.01）。背侧π形钢板在轴向加载以及掌侧和背侧弯曲力作用下对骨折间隙移动的抵抗力最大（p < 0.01）。然而，当掌侧皮质粉碎时，π形钢板对轴向载荷和背侧弯曲力的稳定性明显降低（p < 0.01）。
在这个桡骨远端背侧粉碎性关节外骨折模型中，背侧π形钢板固定比四种掌侧钢板固定对骨折间隙移动的抵抗力更好。在测试的四种掌侧钢板中，AO掌侧锁定钢板和DVR钢板对骨折间隙移动的抵抗力最大。与非锁定钢板技术相比，掌侧锁定技术显著提高了对骨折间隙移动的抵抗力。
