利用壁厚分析法定量判断胫骨骨折骨愈合程度

目的利用壁厚分析法定量判断胫骨骨折愈合程度,为临床判断胫骨骨不连和骨延迟愈合提供直观的诊断依据。方法对48例患者下肢患侧与健侧进行三维建模后,计算最大壁厚(maximum wall thickness,MWT),并进行比值计算,将其对比值(B值)作为骨愈合程度的量化指标全程动态观察。当BMWT20.9且BMWT10.9时判定骨愈合;当BMWT2=0.9～0.7时判定骨愈合不良,定期复查该数值无明显增长,连续两次,可以判定骨不连,需要第二次手术干预治疗;当BMWT30.9,且BMWT10.7和BMWT20.7时,可判定为内固定失效,二次手术中需更换内固定。对于临床诊断进行二次修正,并观察最终临床愈合结果。结果对48例患者各复查时间段影像学进行临床诊断分析及有限元壁厚分析比较,临床判断骨延迟愈合21例,骨不连27例,再利用壁厚分析修正判断,骨延迟愈合34例,骨不连14例。其中2例判断内置物失效,采用更换内固定植骨干预,12例判断内固定仍然有效,单纯植骨手术干预,所有病例最终都取得骨愈合。进行Bowker检验法得到P=0.094,判断壁厚分析方法与临床诊断相符合。结论采用壁厚分析法可以定量分析骨折端的骨愈合程度,实现骨愈合程度的快速计算。病例结果证实有限元壁厚分析法优于单纯临床诊断法,对早期判断骨愈合不良有更好的鉴别诊断意义。

Application of Wall Thickness Analysis in Estimating the Degree of Tibial Fracture Bone Healing

Objective To quantitatively judge the degree of tibial bone healing using the finite element wall thickness analysis method, so as to provide an intuitive diagnostic basis for clinical judgment of tibial union and delayed bone healing. Methods After three-dimensional (3D) modeling for the affected and healthy limb side of 48 patients, the maximum wall thickness (MWT) was calculated, and the ratio (B value) was used as a quantitative index of bone healing. When both BMWT2 and BMWT1 were greater than 0.9, bone healing could be judged. When BMWT2 was between 0.9 and 0.7, bone union was judged to be poor, and there was no significant increase in this value after regular reexamination. When BMWT3 was above 0.9 while both BMWT1 and BMWT2 were smaller than 0.7, it could be judged as internal fixation failure, which should be replaced during the second operation. The clinical diagnosis was revised twice, and the final clinical healing results were observed. Results Clinical diagnosis analysis and finite element wall thickness analysis were carried out in 48 patients during each review period, and 21 cases of delayed bone healing and 27 cases of bone nonunion were judged clinically. Among them, 2 cases were judged to be ineffective, and bone grafting intervention was adopted to replace the internal fixation, 12 cases were judged to be still effective, and all cases were finally healed by surgical intervention of bone grafting alone. By Bowker test, P=0.094 was obtained, indicating that the wall thickness analysis method was consistent with the clinical diagnosis. Conclusions The wall thickness analysis method can be used to quantitatively analyze the degree of bone healing at fracture end and realize the rapid calculation of bone healing degree. The case results in this study show that the finite element wall thickness analysis method is superior to the simple clinical diagnosis method, and has better differential diagnostic significance for early diagnosis of poor bone healing.