Taormina David P, Marcano Alejandro I, Karia Raj, Egol Kenneth A, Tejwani Nirmal C
Hospital for Joint Diseases at NYU Langone Medical Center, NYU School of Medicine, 301 East 17th Street, Suite 1402, New York, NY 10003, USA.
Hospital for Joint Diseases at NYU Langone Medical Center, NYU School of Medicine, 301 East 17th Street, Suite 1402, New York, NY 10003, USA; Jamaica Hospital Medical Center, 8900 Van Wyck Expressway, Jamaica, NY 11418, USA.
Bone. 2014 Jun;63:1-6. doi: 10.1016/j.bone.2014.02.006. Epub 2014 Feb 21.
The benefits of bisphosphonates are well documented, but prolonged use has been associated with atypical femur fractures. Radiographic markers for fracture predisposition could potentially aid in safer medication use. In this case-control designed study, we compared hip radiographic parameters and the demographic characteristics of chronic bisphosphonate users who sustained an atypical femoral fracture with a group of chronic bisphosphonate users who did not sustain an atypical femur fracture and also a group who sustained an intertrochanteric hip fracture. Radiographic parameters included were neck-shaft angle (NSA), hip-axis length (HAL) and center-edge angle (CE). Multivariate regression was used to evaluate the relationship between radiographic measures and femur fracture. Receiver-operating characteristic analysis determined cut-off points for neck-shaft angle and risk of atypical femur fracture. Ultimately, pre-fracture radiographs of 53 bisphosphonate users who developed atypical fracture were compared with 43 asymptomatic chronic bisphosphonate users and 64 intertrochanteric fracture patients. Duration of bisphosphonate use did not statistically differ between users sustaining atypical fracture and those without fracture (7.9 [±3.5] vs. 7.7 [±3.3] years, p=0.7). Bisphosphonate users who fractured had acute/varus pre-fracture neck-shaft angles (p<0.001), shorter hip-axis length (p<0.01), and narrower center-edge angles (p<0.01). Regression analysis revealed associations between neck-shaft angle (OR=0.89 [95% CI=0.81-0.97; p=0.01), center edge angle (OR=0.89 [95% CI=0.80-0.99]; p=0.03), and BMI (OR=1.15 [95% CI=1.02-1.31; p=0.03) with fracture development. ROC curve analysis (AUC=0.67 [95% CI=0.56-0.79]) determined that a cut-off point for neck-shaft angle <128.3° yielded 69% sensitivity and 63% specificity for development of atypical femoral fracture. Ultimately, an acute/varus angle of the femoral neck, high BMI, and narrow center-edge angle were associated with development of atypical femur fracture in long-term bisphosphonate users. Patients on long-term bisphosphonates should be regularly radiographically evaluated in order to assess for potential risk of atypical fracture.
双膦酸盐的益处已有充分记录，但长期使用与非典型股骨骨折有关。骨折易感性的影像学标志物可能有助于更安全地使用药物。在这项病例对照设计研究中，我们比较了发生非典型股骨骨折的慢性双膦酸盐使用者、未发生非典型股骨骨折的慢性双膦酸盐使用者以及发生转子间髋部骨折的一组患者的髋部影像学参数和人口统计学特征。纳入的影像学参数包括颈干角（NSA）、髋轴长度（HAL）和中心边缘角（CE）。采用多变量回归评估影像学测量与股骨骨折之间的关系。受试者操作特征分析确定颈干角的切点和非典型股骨骨折风险。最终，将53例发生非典型骨折的双膦酸盐使用者的骨折前X线片与43例无症状慢性双膦酸盐使用者和64例转子间骨折患者进行比较。发生非典型骨折的使用者与未发生骨折的使用者之间双膦酸盐使用时间在统计学上无差异（7.9 [±3.5] 年 vs. 7.7 [±3.3] 年，p = 0.7）。发生骨折的双膦酸盐使用者骨折前颈干角呈急性/内翻（p < 0.001）、髋轴长度较短（p < 0.01）且中心边缘角较窄（p < 0.01）。回归分析显示颈干角（OR = 0.89 [95% CI = 0.81 - 0.97；p = 0.01]）、中心边缘角（OR = 0.89 [95% CI = 0.80 - 0.99]；p = 0.03）和BMI（OR = 1.15 [95% CI = 1.02 - 1.31；p = 0.03]）与骨折发生有关。ROC曲线分析（AUC = 0.67 [95% CI = 0.56 - 0.79]）确定颈干角 < 128.3° 的切点对非典型股骨骨折发生的敏感性为69%，特异性为63%。最终，股骨颈急性/内翻角、高BMI和窄中心边缘角与长期双膦酸盐使用者非典型股骨骨折的发生有关。长期使用双膦酸盐的患者应定期进行影像学评估，以评估非典型骨折的潜在风险。
