Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu, China.
Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu, China.
World Neurosurg. 2021 Jan;145:e100-e107. doi: 10.1016/j.wneu.2020.09.134. Epub 2020 Oct 1.
Heterotopic ossification (HO) is a potential and severe complication of cervical disc replacement (CDR). However, the underlying mechanism of CDR and its association with preoperative disc height loss (DHL) and postoperative degree of distraction remain unclear. We hypothesized that DHL and postoperative degree of distraction could predict HO after CDR.
Data were obtained from 127 patients who underwent single-level CDR with a minimum follow-up of 2 years. DHL and adjusted degree of distraction (ADD) were obtained from lateral radiographs, and HO was evaluated at the last follow-up appointment. Receiver operating characteristic curves were calculated to verify the diagnostic value of DHL and ADD in predicting HO.
Both DHL and ADD were significantly larger in the HO group than in the non-HO group (P < 0.05). DHL ≥24.97% increased the risk of HO by 5 times (P = 0.003, 95% confidence interval 1.62-15.49), and ADD ≥36.67% increased the risk of HO by 3.87 times (P < 0.001, 95% confidence interval 1.81-8.27). A combined DHL and ADD (combined parameter) cutoff of 60.36 had a sensitivity of 87.18%, specificity of 67.35%, and area under the curve of 0.77 for predicting HO.
DHL and ADD are associated with the development of HO after CDR. The cutoff value of DHL may narrow the criteria for CDR with the aim of reducing HO formation. The combined parameter may help surgeons to select the most suitable implant height to reduce the prevalence of HO.
异位骨化（HO）是颈椎间盘置换术（CDR）的一种潜在且严重的并发症。然而，CDR 的潜在机制及其与术前椎间盘高度丢失（DHL）和术后牵开程度的关系尚不清楚。我们假设 DHL 和术后牵开程度可以预测 CDR 后的 HO。
本研究纳入了 127 例接受单节段 CDR 治疗且随访时间至少 2 年的患者。通过侧位 X 线片获取 DHL 和调整后的牵开程度（ADD），并在最后一次随访时评估 HO。绘制受试者工作特征曲线以验证 DHL 和 ADD 预测 HO 的诊断价值。
HO 组的 DHL 和 ADD 均显著大于非 HO 组（P < 0.05）。DHL≥24.97%使 HO 的风险增加 5 倍（P=0.003，95%置信区间 1.62-15.49），ADD≥36.67%使 HO 的风险增加 3.87 倍（P<0.001，95%置信区间 1.81-8.27）。DHL 和 ADD 的联合参数（combined parameter）截断值为 60.36，其预测 HO 的灵敏度为 87.18%，特异性为 67.35%，曲线下面积为 0.77。
DHL 和 ADD 与 CDR 后 HO 的发生有关。DHL 的截断值可能会缩小 CDR 的标准，以减少 HO 的形成。联合参数可能有助于外科医生选择最合适的植入物高度，以降低 HO 的发生率。
