Swiontkowski M F, Tepic S, Rahn B A, Cordey J, Perren S M
Department of Orthopedics, Harborview Medical Center, Seattle, WA 98104.
Acta Orthop Scand. 1993 Apr;64(2):196-202. doi: 10.3109/17453679308994570.
Miniature swine were used to study the effect of cervical fracture on femoral head blood flow. Laser Doppler flowmetry was used to evaluate femoral head blood flow before and after the fracture, after internal fixation with or without compression, and 8 weeks post-fracture. Fluorescent bone-labeling was performed at 2, 4 and 6 weeks post-fracture. Femoral head blood flow decreased to 40 percent of baseline following fracture, partly from the disruption of venous drainage. Histologically, all femoral heads showed some degree of trabecular thinning, microfracture, and neovascularization when compared with controls. Analyses of the laser Doppler flowmetry data, fluorescent label histology, microradiography and bone densitometry indicated that late (4-6 weeks) revascularization produces severe trabecular mechanical weakening and resultant femoral head collapse. Femoral head ischemia following fracture probably falls along a continuum, with only the more severe cases proceeding to mechanical collapse. Femoral neck fractures in the minipig produce femoral head necrosis of a severity and incidence which closely parallels that of the human population; thus, the minipig is a useful model for further study of complications following femoral neck fracture in humans.
小型猪被用于研究颈椎骨折对股骨头血流的影响。使用激光多普勒血流仪评估骨折前后、有无加压内固定后以及骨折后8周时的股骨头血流情况。在骨折后2、4和6周进行荧光骨标记。骨折后股骨头血流降至基线的40%，部分原因是静脉引流中断。组织学上，与对照组相比，所有股骨头均显示出一定程度的小梁变薄、微骨折和新生血管形成。对激光多普勒血流仪数据、荧光标记组织学、显微放射摄影和骨密度测定的分析表明，晚期（4 - 6周）血管再生会导致严重的小梁机械性弱化并最终导致股骨头塌陷。骨折后股骨头缺血可能呈连续变化，只有较严重的病例才会发展为机械性塌陷。小型猪的股骨颈骨折所导致的股骨头坏死的严重程度和发生率与人类非常相似；因此，小型猪是进一步研究人类股骨颈骨折后并发症有用的模型。
