Department of Orthopedic Surgery, Seoul National University Boramae Medical Center, Seoul, South Korea.
Orthop Traumatol Surg Res. 2013 Oct;99(6):713-8. doi: 10.1016/j.otsr.2013.05.002. Epub 2013 Sep 12.
Metaphyseal comminution is widely considered as a key radiographic parameter that predicts fracture instability for distal radius fractures. However, no quantitative parameter is available to measure this degree of comminution. To quantify metaphyseal comminution objectively, the authors devised and validated the metaphyseal collapse ratio, a new radiographic index.
Seventy-four cases of distal radius fracture in the elderly were included in this analysis. After closed reduction, a strictly lateral plain radiograph was obtained and digitally adjusted. The metaphyseal collapse ratio (MCR) was calculated expressing the maximal radiolucent extent as a percentage of the intercortical distance. Furthermore, correlations between MCR and age, gender, DXA scores, and other radiographic parameters, namely, radial shortening, volar tilt, radial inclination, and the presence of an associated ulnar fracture were investigated.
Mean metaphyseal collapse ratio in the cohort was calculated to be 51.7% by one observer and 53.7% by a second, showing good interobserver and mean intraobserver reliability (0.812, P<0.001 and 0.826, P<0.001, respectively). MCR was found to be significantly correlated with conventionally accepted radiographic parameters of fracture instability, that is, radial shortening (P<0.001), volar tilt (P<0.001), and radial inclination (P=0.002), but not with age, gender, DXA scores, and the presence of a combined ulnar fracture.
Metaphyseal collapse ratio, a novel radiographic parameter, was found to provide a reliable measure of metaphyseal comminution, and to be significantly correlated with other radiographic parameters that predict distal radius fracture instability.
Level III, diagnostic.
干骺端粉碎被广泛认为是预测桡骨远端骨折不稳定性的关键影像学参数。然而，目前尚无定量参数可用于测量粉碎的严重程度。为了客观地量化干骺端粉碎程度，作者设计并验证了一种新的影像学指数——干骺端塌陷比。
本研究纳入了 74 例老年桡骨远端骨折患者。闭合复位后，获得并数字化调整严格的侧位平片。干骺端塌陷比（MCR）的计算方法是将最大透亮区的程度表示为皮质间距离的百分比。此外，还研究了 MCR 与年龄、性别、DXA 评分以及其他影像学参数（桡骨短缩、掌倾、桡偏和合并尺骨骨折）之间的相关性。
由一名观察者计算的队列平均干骺端塌陷比为 51.7%，由第二名观察者计算的平均干骺端塌陷比为 53.7%，均显示出良好的观察者间和观察者内可靠性（分别为 0.812，P<0.001 和 0.826，P<0.001）。MCR 与传统公认的骨折不稳定影像学参数显著相关，即桡骨短缩（P<0.001）、掌倾（P<0.001）和桡偏（P=0.002），但与年龄、性别、DXA 评分和合并尺骨骨折无关。
新型影像学参数——干骺端塌陷比能够可靠地测量干骺端粉碎程度，与预测桡骨远端骨折不稳定性的其他影像学参数显著相关。
III 级，诊断性。
