Bryan颈椎人工椎间盘置换术的长期疗效观察

Long-term clinical outcomes of cervical disc replacement with Bryan prosthesis

目的评估Bryan颈椎人工椎间盘置换术的长期疗效。方法对2004年12月至2008年8月于我院行Bryan颈椎人工椎间盘置换术的20例病人进行回顾性分析,男15例,女5例,平均年龄为(43.85±3.70)岁,其中单节段9例,双节段11例,C_(3/4)2例、C_(4/5)9例、C_(5/6)15例、C_(6/7)5例。(1)收集并比较其术前、术后1周、术后2年及末次随访的改良日本骨科协会(modified Japanese Orthopaedic Association,m JOA)评估治疗分数、疼痛视觉模拟量表(visual analogue scale,VAS)评分、颈椎功能障碍指数(neck disability index,NDI)以及Odoms分级。(2)通过其术前、术后早期及末次随访时的X线侧位片及颈椎过屈过伸位片,评估其颈椎曲度、颈椎活动度(ROM)。(3)MRI T2加权像上根据Miyazaki分级标准评估Bryan人工椎间盘置换术后邻近节段的退变情况。(4)通过X线片及CT片根据Mc Afee标准评价异位骨化的发生情况。结果 (1)术前及末次随访时的m JOA评分分别为(13.30±2.83)分、(15.25±2.07)分,VAS评分分别为(4.10±3.81)分、(1.55±1.53)分,NDI分别为(11.45±9.52)分、(6.00±4.78)分,所有评价指标末次随访时较术前均有显著改善,差异均有统计学意义(P均<0.05)。末次随访时Odoms分级为优8例,良8例,可2例,差2例。(2)脊柱功能单位(FSU)曲度及C_2~C_7曲度:术前分别为2.33°±4.08°、18.78°±6.68°,术后早期为4.12°±6.43°、20.00°±9.98°,末次随访时分别为3.21°±6.56°、15.61°±6.73°。FSU ROM及C_2~C_7ROM:术前分别为9.15°±2.80°、47.28°±9.75°,术后早期为9.27°±3.83°、40.81°±14.66°,末次随访分别为9.37°±3.97°、42.03°±10.97°。3个时间点的FSU曲度及FSU ROM比较,差异均无统计学意义(P均>0.05),但C_2~C_7ROM术后较术前明显减少,与邻近节段ROM变化趋势一致。末次随访时,43个邻近节段中46.5%发生邻近节段退变(adjacent segment degeneration,ASD),以C_(5/6)最为常见,但均无临床表现;末次随访时31个手术节段中有23例(74.2%)发生异位骨化,其中严重异位骨化(Ⅲ、Ⅳ级)发生率为22.6%,C_(5/6)最为常见。结论 Bryan颈椎人工椎间盘置换术治疗颈椎退变性疾病可以取得持久稳定的临床效果,尽管异位骨化发生率较高,但大部分保留手术节段活动,同时邻近节段仍可见退变,但均无临床症状。

Objective To investigate the long-term clinical outcomes of cervical disk replacement with Bryan prosthesis.Methods The study retrospectively evaluated the long-term outcome of the patients who were subjected to Bryan cervical arthroplasty in our hospital from December2004to August2008.Clinical outcome was accessed by mJOA,VAS,NDI score pre-and post-operation,and classified as excellent,good,fair or poor according to the Odom’s grading criteria at final follow-up.The alignment was measured on lateral radiographs and range of motion was defined as the difference of Cobb angle between the dynamic radiographs.The adjacent segment degeneration was noted according to the Miyazaki’s grading system on MRI.Heterotopic ossification was accessed and classified according to the McAfee classification.Results Preoperation and at final follow?up,the mJOA score was13.30±2.83and15.25±2.07,the VAS score was4.10±3.81and1.55±1.53,the NDI score was11.45±9.52and6.00±4.78,respectively.All of above showed statistically significant difference(P<0.05for all).According to the Odom’s criteria,8cases obtained excellent effect,8good effect,2fair effect and2poor effect.The FSU and C2-C7Cobb angle were2.33°±4.08°and18.78°±6.68°preoperation,4.12°±6.43°and20.00°±9.98°at early follow-up,and3.21°±6.56°and15.61°±6.73°at final follow-up,final follow-up,without significant difference.The ROM of C2?C7was reduced from47.28°±9.75°preoperation to42.03°±10.97°at final follow-up,in accordance with the change of ROM of adjacent segment.According to the Miyazaki grading criteria,46.5%of these43adjacent segments showed radiological adjacent segment degeneration(ASD),but all without clinical symptoms.Heterotopic ossification was detected in23(74.2%)of the31protheses,while22.6%of them were classified as gradeⅢor gradeⅣ.In addition,both ASD and heterotopic ossification were presented commonly at C5/6.Conclusion Cervical arthroplasty with Bryan prosthesis provides a favorable clinical and radiological outcome for cervical degenerative disease.The motion of treated level is well preserved,although different grades of heterotopic ossification are observed.The prevalence of ASD is moderate and no adjacent segment disease is noted.