Department of Orthopedic Surgery, Spine Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-Dong, Kangnam-Gu, Seoul 135-710, Korea.
Int Orthop. 2011 Aug;35(8):1197-201. doi: 10.1007/s00264-010-1095-4. Epub 2010 Jul 21.
The main goal of total disc replacement (TDR) is to preserve motion. Despite reports of good clinical outcomes, various degrees of heterotopic ossification after TDR have been reported. The purpose of this study was to investigate the prevalence and its clinical relevance of heterotopic ossification. We evaluated 65 consecutive patients (82 segments) with mean follow-up duration of 45 months (range, 12-88 months). Two kinds of prosthesis, ProDisc® for 75 segments (91.5%) and CHARITE™ for seven segments (8.5%), were used. Patients with heterotopic ossification were compared with those without heterotopic ossification with regard to segmental flexion-extension ROM, VAS and ODI. We analysed the occurrence site by nine zones. Heterotopic ossification was detected in 25 out of 82 segments (30.5%) at a mean follow-up of 17 months. According to McAfee's classification, there was Class-I heterotopic ossification in eight segments (9.8%), Class-II in 12 segments (14.6%), and Class-III in five segments (6.1%). There was no Class-IV heterotopic ossification. There were no significant differences in the segmental ROM, VAS and ODI between the patients with Class-I or Class-II heterotopic ossification and those without heterotopic ossification The segmental ROM in the patients with Class-III heterotopic ossification was significantly decreased compared with the patients without heterotopic ossification (p = 0.018). But VAS and ODI were not significantly different compared with those of patients with no heterotopic ossification. Most heterotopic ossification (82.5%) was detected in the anterior and posterior aspects. In conclusion, most of the heterotopic ossification (Classes I and II) did not affect segmental ROM and clinical outcomes such as pain or function. In Class-III heterotopic ossification segmental ROM was decreased, but it did not affect clinical outcomes.
全椎间盘置换术（TDR）的主要目标是保留运动。尽管有良好的临床结果报告，但TDR 后存在不同程度的异位骨化。本研究旨在探讨异位骨化的发生率及其临床相关性。我们评估了 65 例连续患者（82 个节段），平均随访时间为 45 个月（范围 12-88 个月）。使用了两种假体，ProDisc® 75 个节段（91.5%）和 CHARITE™ 7 个节段（8.5%）。比较了有异位骨化的患者和无异位骨化的患者在节段屈伸 ROM、VAS 和 ODI 方面的差异。我们通过九个区域分析了异位骨化的发生部位。在平均 17 个月的随访中，82 个节段中有 25 个（30.5%）检测到异位骨化。根据 McAfee 分类，8 个节段（9.8%）为 I 级异位骨化，12 个节段（14.6%）为 II 级，5 个节段（6.1%）为 III 级。没有 IV 级异位骨化。I 级或 II 级异位骨化患者与无异位骨化患者的节段 ROM、VAS 和 ODI 无显著差异。III 级异位骨化患者的节段 ROM 明显低于无异位骨化患者（p=0.018）。但 VAS 和 ODI 与无异位骨化患者无显著差异。大多数异位骨化（82.5%）发生在前部和后部。总之，大多数异位骨化（I 级和 II 级）并不影响节段 ROM 和疼痛或功能等临床结果。在 III 级异位骨化中，节段 ROM 减少，但不影响临床结果。
