Wang Zhen, Zheng Chong, Wen Siyuan, Wang Junfei, Zhang Zitao, Qiu Xusheng, Chen Yixin
Department of Orthopedics, Drum Tower Hospital Clinical College of Nanjing University, Nanjing, People's Republic of China.
Department of Orthopedics, Changzhou Traditional Chinese Medicine Hospital Affiliated to Nanjing University of Chinese Medicine, Changzhou, People's Republic of China.
Infect Drug Resist. 2019 Jul 1;12:1827-1831. doi: 10.2147/IDR.S213099. eCollection 2019.
Infected nonunion after open reduction internal fixation (ORIF) is a serious complication. The aim of this study was to evaluate the usefulness of serum D-dimer for preoperative diagnosis of infected nonunion.
Patients undergoing debridement and external fixation for infected nonunion (n=32) and replacement of internal fixation due to aseptic failure (n=34) were enrolled and compared in this retrospective study. The optimum cutoff value of D-dimer for identification of infected nonunion was determined by calculating the Youden J statistic. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of four preoperative laboratory parameters-serum D-dimer level, white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP)-for diagnosis of infected nonunion were compared.
Serum D-dimer level was significantly higher in patients with infected nonunion than in patients with aseptic nonunion: 2.62 mg/mL (range, 0.13-11.90 mg/mL) vs 0.35 mg/mL (range, 0.07-6.46 mg/mL; <0.001). WBC count, CRP, and ESR demonstrated sensitivity of 12.5% (95% CI: 4.08-29.93), 40.6% (95% CI: 24.22-59.21), and 56.3% (95% CI: 37.88-73.16), respectively, and specificity of 94.1% (95% CI: 78.94-98.97), 88.2% (95% CI: 71.61-96.16), and 85.3% (95% CI: 68.17-94.46), respectively. Using the Youden index, 1.70 mg/mL was determined as the optimal threshold value for serum D-dimer for the diagnosis of infected nonunion. The sensitivity and specificity of serum D-dimer (>1.70 mg/mL) were 75.0% (95% CI: 56.25-87.87) and 91.2% (95% CI: 75.19-97.69).
Serum D-dimer level may be useful for preoperative prediction of infected nonunion in patients after ORIF.
切开复位内固定术（ORIF）后感染性骨不连是一种严重的并发症。本研究的目的是评估血清D-二聚体在术前诊断感染性骨不连中的作用。
本回顾性研究纳入并比较了因感染性骨不连接受清创和外固定的患者（n = 32）以及因无菌性失败而更换内固定的患者（n = 34）。通过计算约登指数确定D-二聚体用于识别感染性骨不连的最佳临界值。比较了四项术前实验室参数——血清D-二聚体水平、白细胞（WBC）计数、红细胞沉降率（ESR）和C反应蛋白（CRP）——诊断感染性骨不连的敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）。
感染性骨不连患者的血清D-二聚体水平显著高于无菌性骨不连患者：2.62 mg/mL（范围0.13 - 11.90 mg/mL） vs 0.35 mg/mL（范围0.07 - 6.46 mg/mL；P < 0.001）。WBC计数、CRP和ESR的敏感性分别为12.5%（95%CI：4.08 - 29.93）、40.6%（95%CI：24.22 - 59.21）和56.3%（9�%CI：37.88 - 73.16），特异性分别为94.1%（95%CI：78.94 - 98.97）、88.2%（95%CI：71.61 - 96.16）和85.3%（95%CI：68.17 - 94.46）。使用约登指数，确定血清D-二聚体诊断感染性骨不连的最佳阈值为1.70 mg/mL。血清D-二聚体（>1.70 mg/mL）的敏感性和特异性分别为75.0%（95%CI：56.25 - 87.87）和91.2%（95%CI：75.19 - 97.69）。
血清D-二聚体水平可能有助于术前预测ORIF术后患者的感染性骨不连。
