Ellsasser J C, Moyer C F, Lesker P A, Simmons D J
J Trauma. 1975 Oct;15(10):869-76. doi: 10.1097/00005373-197510000-00005.
Experiments in rabbits were conducted to test the clinical propositions that a) the risk of nonunion in certain long bone fractures can be sharply reduced by open reduction and internal fixation, and b) that there is an optimum critical period following trauma in which this procedure should be carried out to facilitate healing. Bilateral standard open fractures of rabbit radii were internally fixed by intramedullary K-wires immediately or at 5, 10, and 17 days after trauma. These bones were subjected to stress and histometric analyses at 4-56 days after the initial fractures. The observations suggested that the pace of fracture healing could be optimized by time-delay surgery. The most exuberant and strongest calluses developed when the bones were fixed 10 days after fracture, and the rate of healing was improved. Delay times of 5 or 17 days did not provide better healing than that achieved by an immediate operation. Callus quality, in terms of the proportion of fiber bone, lamellar bone, and cartilage, was similar in all groups. The tensile strengths of the bones during callus formation were highly correlated with the ratio of callus/cortical bone areas (p less than 0.01).
进行了兔实验，以检验以下临床观点：a）通过切开复位内固定可大幅降低某些长骨骨折不愈合的风险；b）创伤后存在一个最佳关键期，在此期间进行该手术有助于促进愈合。兔双侧桡骨标准开放性骨折在创伤后立即或在创伤后5天、10天和17天用髓内克氏针进行内固定。在初次骨折后4 - 56天对这些骨骼进行应力和组织计量学分析。观察结果表明，通过延迟手术可优化骨折愈合速度。骨折后10天固定骨骼时形成的骨痂最旺盛、最强壮，愈合速度也有所提高。5天或17天的延迟时间并未比立即手术带来更好的愈合效果。就纤维骨、板层骨和软骨的比例而言，所有组的骨痂质量相似。骨痂形成期间骨骼的拉伸强度与骨痂/皮质骨面积之比高度相关（p小于0.01）。
