Ruomu Qu, Haoxiang Wang, Tian Xia, Hanbo Geng, Yanbin Zhao, Yinze Diao, Xin Chen, Shengfa Pan, Li Zhang, Shaobo Wang, Fengshan Zhang, Yu Sun, Zhong Jun Liu, Feifei Zhou
Orthopedic Department, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, China.
Engineering Research Center of Bone and Joint Precision Medicine, Peking University, Beijing, China.
J Orthop Surg Res. 2025 Jul 9;20(1):633. doi: 10.1186/s13018-025-06056-9.
The 3D-printed artificial vertebral body (AVB) was designed with theoretically better biomechanical properties than traditional implants to decrease the incidence of implant subsidence. However, implant subsidence still occurs, with the potential risk factors for AVB subsidence remaining unknown. This study aimed to identify the risk factors for early subsidence of AVB after single-level anterior cervical corpectomy and fusion (ACCF).
Consecutive patients who underwent single-level ACCF using 3D-printed AVB for cervical spondylotic myelopathy between 2018 and 2022 were included. Preoperative, immediate postoperative, and 3-month postoperative X-ray scans were evaluated. Radiological assessment included segmental height (SH), intraoperative retraction height, cervical alignment parameters, bone quality and implant sagittal size ratio. Early subsidence was defined as an SH loss ≥ 2 mm based on 3-month radiographs.
Of the included 98 patients (52 males, 46 females, average age: 51.8 ± 10.1), 35(35.7%) experienced early subsidence. The subsidence group exhibited significantly higher age, segmental sagittal vertical axis, cervical lordosis, C7 slope, and segmental slope, alongside lower implant sagittal size ratio. Correlation analysis revealed that SH loss is significantly positively correlated with intraoperative retraction height, segmental SVA, C7 slope, segmental slope, and negatively with the ratio of implant sagittal diameter compared to vertebra. Forward multivariable logistic regression indicated that greater age (p = 0.029), intraoperative retraction height (p < 0.001), and segmental slope (p = 0.006) were significant risk factors, while a higher implant sagittal size ratio (p = 0.004) was a protective factor against AVB subsidence.
Increased age, segmental slope, intraoperative retraction height, and a lower implant sagittal size ratio are significant risk factors for AVB subsidence. Surgeons should consider these factors in surgery planning and avoid excessive intraoperative retraction.
3D打印人工椎体（AVB）在理论上设计得具有比传统植入物更好的生物力学性能，以降低植入物下沉的发生率。然而，植入物下沉仍会发生，AVB下沉的潜在风险因素尚不清楚。本研究旨在确定单节段颈椎前路椎体次全切除融合术（ACCF）后AVB早期下沉的风险因素。
纳入2018年至2022年间连续接受3D打印AVB治疗脊髓型颈椎病的单节段ACCF患者。评估术前、术后即刻和术后3个月的X线扫描。影像学评估包括节段高度（SH）、术中牵开高度、颈椎对线参数、骨质和植入物矢状径比例。早期下沉定义为基于术后3个月X线片节段高度丢失≥2mm。
纳入的98例患者（52例男性，46例女性，平均年龄：51.8±10.1岁）中，35例（35.7%）发生早期下沉。下沉组年龄、节段矢状垂直轴、颈椎前凸、C7斜率和节段斜率显著更高，而植入物矢状径比例更低。相关性分析显示，节段高度丢失与术中牵开高度、节段矢状垂直轴、C7斜率、节段斜率显著正相关，与植入物矢状径与椎体直径之比显著负相关。向前多变量逻辑回归表明，年龄较大（p = 0.029）、术中牵开高度（p < 0.001）和节段斜率（p = 0.006）是显著风险因素，而较高的植入物矢状径比例（p = 0.004）是防止AVB下沉的保护因素。
年龄增加、节段斜率、术中牵开高度和较低的植入物矢状径比例是AVB下沉的显著风险因素。外科医生在手术规划时应考虑这些因素，并避免术中过度牵开。
