股骨骨折髓内钉固定术前后髓内压变化与脂肪入侵的研究

Change of intramedullary pressure and fat intravasation during intramedully nailing of fresh femoral fractures

[目的]研究股骨骨折早期开放式髓内钉固定术中髓内压的变化及其与脂肪入侵的关系。[方法]50例新鲜股骨骨折患者伤后早期行开放式髓内钉固定术。手术前在股骨上安置通入髓腔的中空螺纹探针并与压力传感器相连,监测整个手术过程中髓内压的变化情况并将患者分为髓内压升高组和无髓内压升高组。手术前及髓内钉刚推入后分别自患侧股静脉采血5ml,将血凝块行冰冻切片油红“O”染色镜检游离脂肪滴。将髓内压升高组及无髓内压升高组血中游离脂肪检测的阳性率进行对比分析。[结果](1)术中在一定条件产生“活塞效应”时能监测到髓内压升高现象。(2)髓内压升高组术中静脉血游离脂肪病理学检测阳性率明显高于术前(P<0.01),无髓内压升高组术前术中阳性率无显著性差异;两组患者术前阳性率无明显差别,髓内压升高组术中阳性率明显高于无髓内压升高组(P<0.01)。[结论]股骨骨折早期开放式髓内钉内固定手术中在一定条件下产生的“活塞效应”可使髓内压升高;髓内压升高是股骨骨折早期开放式髓内钉内固定术中导致骨髓脂肪入侵的重要因素。

[Objective] To study the factors leading to intramedullary pressure （IMP） change during openintramedullynailing （OIMN） of fresh femoral fractures and the relation between fat intravasation and IMP. [ Method] Fifty patients with femoral fractures were submitted to OIMN in early stage after injury. Before operation, a hollow probe was screwed into the medullary cavity and linked with a moni- tor to record the dynamic pressure change during the OIMN process. The patients were divided into 2 groups according to their IMP. 5ml blood was taken from femoral vein of the affected limb individually before operation and just after fixation of the intramedullary nail. The blood clots were made into frozen sections and stained by oil red - 0 to find the free fat. The positive rate of free fat in pathological detection between patients with increased IMP and those without were compared. [ Result] （ 1 ） Increased IMP could be recorded in some patients with ＂ piston effect＂ resulted from a certain condition during OIMN. （2） For patients with increased IMP, the positive rate of free fat through pathological detection during the operation was significantly higher than that of before （ p （ o. ol）, but that of patients without increased IMP did not change significantly. The positive rates of the two groups did not have significant difference than those of before operation. During operation, the positive rate of patients with increased IMP was significant higher than that of patients without pressure imcreasing （P〈0.01）. [ Conclusion] The ＂ piston effect＂ could lead to increased IMP during OIMN of fresh femoral fractures. The increased IMP is an important factor leading to marrow fat intravasation.