Departments of Orthopaedics and Rehabilitation.
Cell Biology, Yale School of Medicine, New Haven, CT.
J Pediatr Orthop. 2020 Oct;40(9):e889-e893. doi: 10.1097/BPO.0000000000001587.
The creation of accurate markers for skeletal maturity has been of significant interest to orthopaedic surgeons. They guide the management of diverse disorders such as adolescent idiopathic scoliosis, leg length discrepancy, cruciate ligament injuries, and slipped capital femoral epiphysis. Multiple systems have been described to predict growth using radiographic skeletal markers; however, no such system has yet been developed for the proximal tibia. The purpose of this study was to establish quantitative radiographic parameters within the proximal tibia that can be used to assess degree of skeletal maturity.
From the Bolton Brush collection, 94 children, consisting of 49 girls and 4 boys between the ages of 3 and 18 years old, were followed annually throughout growth with serial radiographs and physical examinations. Final height at maturity was used to calculate the growth remaining at each visit. Multiple measurements for each knee radiograph were performed and correlated with the percentage of growth remaining. Tibial epiphysis width, tibial metaphysis width, and height of the lateral tibial epiphysis were measured on each film and the composite ratios between each of these sets of variables along with their respective accuracy and reliability were calculated. Single and multiple linear regression models were constructed to determine accuracy of prediction. Interobserver and intraobserver studies were performed with 4 investigators ranging from medical student to senior attending and calculated using the intraclass correlation coefficient. All 4 examiners measured all of the subjects and the ratios created were averaged.
Tibial epiphysis width, tibial metaphysis width, and height of the lateral tibial epiphysis were all found to be strongly correlated with growth remaining with R values ranging from 0.57 to 0.84. In addition, all 3 ratios were found to be reliable with intraobserver and interobserver intraclass correlation coefficients ranging from 0.92 to 0.94 and 0.80 to 0.94, respectively. A multiple linear regression model demonstrated that combining these 3 ratios allows for a predictive R value of 0.917, showing that these ratios when combined were highly predictive of growth remaining. All findings were independent of sex (P=0.996).
We describe 3 measurements that can easily be obtained on an anteroposterior radiograph of the knee. We demonstrate that ratios of these variables can be measured reliably and correlate closely with remaining growth, independent of sex. Together, we believe that these factors will improve the accuracy of determining growth from lower extremity radiographs that include the proximal tibia.
This study provides a new quantitative technique to evaluate growth in the lower extremity, which can inform a range of conditions including adolescent idiopathic scoliosis, leg length discrepancy, cruciate ligament injury, and slipped capital femoral epiphyses.
准确预测骨骼成熟度的标志物一直是矫形外科医生关注的焦点。这些标志物可以指导多种疾病的管理，如青少年特发性脊柱侧凸、肢体长度差异、十字韧带损伤和股骨头骨骺滑脱。已经有多种系统被描述用于通过放射性骨骼标志物来预测生长，然而，目前还没有为胫骨近端开发出这样的系统。本研究的目的是建立可以用于评估骨骼成熟度的胫骨近端定量放射学参数。
从 Bolton Brush 数据库中选择了 94 名 3 至 18 岁的儿童，其中包括 49 名女孩和 4 名男孩，在整个生长过程中每年进行系列 X 线和体格检查。最终身高用于计算每次就诊时的剩余生长量。对每个膝关节 X 线片进行多次测量，并与剩余生长量进行相关性分析。对每个胶片测量胫骨骨骺宽度、胫骨干骺端宽度和外侧胫骨骨骺高度，并计算这些变量组之间的复合比值及其各自的准确性和可靠性。构建单因素和多因素线性回归模型以确定预测的准确性。采用 4 名从医学生到高级主治医生的观察者进行了观察者间和观察者内研究，并使用组内相关系数进行了计算。所有 4 名检查者都测量了所有的受试者，并对创建的比值进行了平均。
胫骨骨骺宽度、胫骨干骺端宽度和外侧胫骨骨骺高度与剩余生长量均呈高度相关，R 值范围为 0.57 至 0.84。此外，所有 3 个比值的观察者内和观察者间组内相关系数均可靠，范围分别为 0.92 至 0.94 和 0.80 至 0.94。多元线性回归模型表明，将这 3 个比值结合起来，可以得到预测 R 值为 0.917，表明这些比值在组合后对剩余生长具有高度预测性。所有发现均与性别无关（P=0.996）。
我们描述了 3 种可以在膝关节前后位 X 线片上轻松获得的测量方法。我们证明，这些变量的比值可以可靠地测量，并且与剩余生长密切相关，与性别无关。综上所述，我们相信这些因素将提高包括胫骨近端在内的下肢 X 线片确定生长的准确性。
本研究提供了一种新的定量技术来评估下肢生长情况，可用于多种疾病的评估，如青少年特发性脊柱侧凸、肢体长度差异、十字韧带损伤和股骨头骨骺滑脱。
