Department of Spine Surgery, Beijing Jishuitan Hospital, Beijing, China.
Orthop Surg. 2020 Dec;12(6):1760-1767. doi: 10.1111/os.12743. Epub 2020 Oct 12.
This study focused on the assessment of paravertebral ossification (PO) after cervical disc arthroplasty (CDA) using computed tomography (CT) images.
In this retrospective study, 52 patients (from 2004 to 2010) who received CDA at a single center were included (32 males). Preoperative and follow-up X-ray and CT images of all patients who underwent single-level CDA were collected. PO from the C2/3 to C7/T1 in each patient was graded based on a CT grading system. Each segment was divided into operative level, adjacent level, or non-adjacent level. The McAfee' classification system was used to grade PO using X-ray plain film. The range of motion (ROM) and scores of neurological symptoms (Japanese Orthopaedic Association [JOA] score and Neck Disability Index [NDI]) at both preoperative and final follow-up time were acquired. Progression and classification of PO in each group was compared using the chi-square test. ROM between groups were compared using independent t-test. JOA score and NDI between groups were compared using Mann-Whitney U test.
The average follow-up time was 81.2 months. In comparison with the preoperative status, the progression of PO development in left and right areas (the Luschka joints areas) in the operative level groups was significantly more severe (area L,χ value = 36.612, P < 0.001; area R, χ value = 39.172, P < 0.001) than the non-adjacent level groups. In contrast, although the prevalence of PO in all areas of the adjacent level groups was higher than that of the non-adjacent level group in the same segments, there was no significant difference (P > 0.05) in the progression of PO development. The follow-up high-grade (grades III and IV) PO incidence rate using X-ray grading system (3.85%) was significantly lower than that using CT grading system in area L (42.31%) and R (38.46%), but close to that in area A (5.77%) and P (1.92%). The final follow-up ROM was not significantly different with preoperative ROM in patients with low-grade PO (9.47° ± 4.12° vs. 9.76° ± 3.69°, P = 0.794). However, in patients with high-grade PO, the final follow-up ROM was significantly lower than preoperative ROM (5.77° ± 3.32° vs. 9.28° ± 4.15°, P < 0.001). There was no significant difference for JOA score and NDI at follow-up between patients with high-grade and low-grade PO (JOA, 16.2 ± 1.1 vs. 16.8 ± 0.9, P = 0.489; NDI, 8.9 ± 6.1 vs. 8.0 ± 7.3, P = 0.317).
High-grade PO was observed in the areas of the Luschka joints at the operative level after CDA, which was difficult to observe using X-ray plain film. The PO formation at adjacent segments was not significant.
本研究旨在使用计算机断层扫描（CT）图像评估颈椎间盘置换（CDA）后的椎旁骨化（PO）。
在这项回顾性研究中，纳入了 52 名（2004 年至 2010 年）在单中心接受 CDA 的患者（男性 32 名）。收集了所有接受单节段 CDA 的患者术前和随访的 X 射线和 CT 图像。根据 CT 分级系统对每位患者从 C2/3 到 C7/T1 的 PO 进行分级。每个节段分为手术水平、相邻水平或非相邻水平。使用 Mcafee'分级系统对 X 射线平片进行 PO 分级。获取术前和最终随访时的运动范围（ROM）和神经症状评分（日本矫形协会 [JOA] 评分和颈部残疾指数 [NDI]）。使用卡方检验比较每组 PO 的进展和分类。使用独立 t 检验比较组间的 ROM。使用 Mann-Whitney U 检验比较组间的 JOA 评分和 NDI。
平均随访时间为 81.2 个月。与术前相比，手术水平组左侧和右侧（Luschka 关节区）的 PO 进展明显更严重（区域 L，χ 值=36.612，P<0.001；区域 R，χ 值=39.172，P<0.001）与非相邻水平组。相比之下，尽管相邻水平组所有区域的 PO 患病率均高于同一节段的非相邻水平组，但 PO 进展无显著差异（P>0.05）。使用 X 射线分级系统（3.85%）的随访高级别（III 级和 IV 级）PO 发生率明显低于 L 区（42.31%）和 R 区（38.46%）的 CT 分级系统，但接近 A 区（5.77%）和 P 区（1.92%）。在低级别 PO 患者中，终末随访 ROM 与术前 ROM 无显著差异（9.47°±4.12° vs. 9.76°±3.69°，P=0.794）。然而，在高级别 PO 患者中，终末随访 ROM 明显低于术前 ROM（5.77°±3.32° vs. 9.28°±4.15°，P<0.001）。高级别 PO 患者和低级别 PO 患者的随访 JOA 评分和 NDI 无显著差异（JOA，16.2±1.1 vs. 16.8±0.9，P=0.489；NDI，8.9±6.1 vs. 8.0±7.3，P=0.317）。
在 CDA 后，在 Luschka 关节的手术水平区域观察到高级别的 PO，这在 X 射线平片上难以观察到。相邻节段的 PO 形成并不显著。
