三维手段定量评估股骨颈骨折复位质量与股骨头坏死的相关性

摘要

背景：骨折复位质量对骨折愈合与肢体功能恢复至关重要，传统X射线片与断层CT对量化与直观观察骨折移位效果不佳。Mimics 具有快速构建骨骼模型和空间测量的功能，为定量三维空间量化复位质量提供了可能。　　目的：利用三维测量方法对 X 射线评估为复位满意的股骨颈骨折患者进行残留移位再测量，并探究残留移位与股骨头坏死的相关性。　　方法：将2012年1月至2013年12月于武警后勤学院附属医院关节三科接受治疗的141例股骨颈骨折患者纳入研究，按骨折移位程度分组，无移位组44例(Garden1&2)，移位组97例(Garden3&4)。利用CT的DICOM数据建立每个患者的三维模型，测量修复术后股骨颈骨折患者的残留移位参数：股骨头中心距离、股骨头小凹距离及空间偏转距离。对患者股骨头坏死情况进行随访，探究残留移位程度与股骨头坏死的相关性。　　结果与结论：①患者随访时间为25-43个月，无移位组和移位组中分别有7例和21例患者罹患股骨头坏死；②无移位组中股骨头中心距离、股骨头小凹距离、空间偏转角度分别为(7.44±2.84) mm，(11.75±4.12) mm，(17.68±8.99)°；移位组分别为(6.51±3.75)mm，(9.34±5.27) mm，(14.67±7.43)°，两组中除股骨头中心距离外差异均有显著性意义(P<0.05)；③提示复位质量欠佳是引起股骨头坏死的重要因素之一；同时 X 射线在描述空间立体移位和角度中存在不足，在评估股骨颈骨折的复位质量时具有局限性；而利用三维测量手段评估骨折复位质量具有一定的优越性。%BACKGROUND:Reduction quality is essential for the healing and function of limb. Traditional X-ray and CT scans have some limitationsin quantitatively and visualy observing the reduction quality of the remnant fracture in three-dimensional displacements. Mimics have advantages in bone rapid modeling and three-dimensional measurement, which offers the chance in quantifying the reduction quality of the displacement in three-dimensional methods. OBJECTIVE:To measure residual displacement in femoral neck fracture patients with satisfactory reduction by using three-dimensional measurement method, and to evaluate the association between residual displacement and femoral head necrosis. METHODS:We enroled 141 patients with femoral neck fracture, who were treated in the Third Department of Joint, Affiliated Hospital of Logistics University of People’s Armed Police Force from January 2012 to December 2013. Al patients were divided into undisplaced fracture group (n=44; Garden1&2) and displaced fracture group (n=97; Garden3&4). Based on DICOM data of CT files, three-dimensional models were constructed in each patient. Three parameters were measured: displacement of femoral head’s center, fossa capitis femoris and rotational displacement. Femoral head necrosis was folowed up. The correlation between residual displacement and femoral head necrosis was explored. RESULTS AND CONCLUSION:(1) The duration of folow-up in those patients ranged from 25 to 43 months. Femoral head necrosis occurred in 7 cases from the undisplaced fracture group and 21 cases from the displaced fracture group. (2) The three parameters (displacement of femoral head’s center, fossa capitis femoris and rotational displacement) were respectively (7.44±2.84) mm, (11.75±4.12) mm and (17.68±8.99)° in the undisplaced group, and (6.51±3.75) mm, (9.34±5.27) mm and (14.67±7.43)° in the displaced group. Except displacement of femoral head’s center, significant differences in the other two parameters were detected between the two groups (P< 0.05). (3) These findings suggest that poor reduction quality is the main factor causing femoral head necrosis. X ray is insufficient to describe the spatial shift and the angle, and has limitations in assessing the reductionquality of femoral neck fracture. Three-dimensional measurement has certain advantages to assess quality of fracture reduction.