Discover人工颈椎间盘置换术后异位骨化的临床研究

目的　分析Discover人工颈椎间盘置换术治疗颈椎病的异位骨化形成原因及防治对策。 方法 回顾性分析23例应用Discover人工颈椎间盘置换术治疗的颈椎病患者。 在术前、术后1周及末次随访时的颈椎X线片上测量置换节段矢状位、冠状位活动度，并根据McAfee分级法判断末次随访时置换节段的异位骨化情况。 结果 术后患者23例患者均获随访，时间27~36个月。末次随访置换节段矢状位活动范围（5.5±2.2）°；冠状位左右侧屈活动范围分别为（3.4±1.2）°和（3.6 ±0.8）°。共有5例患者在末次随访时出现置换节段假体周围异位骨化，发生率21.7%。 结论 DISCOVER人工颈椎间盘置换术治疗颈椎病存在一定的异位骨化发生率，与文献报道相符，术者应有意识地预防异位骨化的发生以避免置换节段的活动度丢失。

Clinical observation of heterotopic ossification after Discover cervical disc replacement

Objective To analyze the cause of heterotopic ossification of Discover artificial cervical disc replacement in the treatment of cervical vertebra disease and to explore preventive countermeasures. Methods We retrospectively reviewed radiographic and clinical outcomes in 23 patients who received the Discover cervical disc prosthesis. Static and dynamic X ray was taken for measurement of the range of motion. Replacement segment was assessed for heterotopic ossifications at the latest follow-up according to McAfee classification method. Results 23 patients were followed up for 27~36 months. In the last follow-up, the average sagittal range of motion was 5.5°±2.2°，and the average coronal range of motion was 3.4°±1.2° and 3.6°±0.8°. A total of 5 patientsdemonstrated the prosthesis replacement segmental heterotopic ossification at the last follow-up, the incidence being 21.7%. Conclusions heterotopic ossification can occur after DISCOVER artificial cervical disc replacement in the treatment of cervical spondylosis; the incidence is consistent with the literature report; the surgeon should try consciously to prevent the occurrence of heterotopic ossification in order to avoid the loss of the mobility of the replacement segment.