下颈椎曲度远期变化与枕颈融合角度的关系

Correlation between occipital-cervical fusion angle and long-term changes in lower cervical curvature

目的分析枕颈融合角度与下颈椎曲度远期变化的相关性。方法选取2001年6月至2011年6月于郑州大学第一附属医院就诊的28例寰枢椎脱位或颅底凹陷患者,所有患者都接受后路枕颈固定融合术治疗,利用PACS系统中侧位颈椎X线片对OC2A和C2~C7Cobb角度进行测定,对患者术前、术后及随访时资料进行收集测量,按照融合角度将患者分为A、B、C组,采用Spearman相关性分析检验枕颈融合角度与下颈椎曲度变化的相关性。结果28例患者中男12例,女16例;年龄(38.5±12.4)岁;随访时间为(158.25±62.34)个月。5例A组患者OC2A固定角度在10°以内,其术后6个月、术后5年及末次随访时,OC2A值组内差异有统计学意义(P<0.01)。4例C组患者固定在20°以上,其术后6个月、术后5年及末次随访时,C2~C7 Cobb角组内差异有统计学意义(P<0.01)。C组中OC2A值与C2~C7 Cobb角度呈负相关(r=-0.797,P<0.01)。结论OC2A与C2~C7 Cobb角度明显相关,行后路枕颈固定融合术时应选取适宜的枕颈融合角度,OC2A以20°以内为宜,超过20°的OC2A可造成下颈椎远期退变甚至反弓。

Objective To analyze the correlation between the occipital-cervical fusion angle and the long-term changes in the curvature of the lower cervical spine.Methods A total of 28 patients with atlantoaxial dislocation or skull base depression who were treated in the First Affiliated Hospital of Zhengzhou University from June 2001 to June 2011 were selected.All patients received posterior occipital-cervical fixation and fusion.The OC2A and C2-C7 Cobb angles were measured by cervical X-ray films,and the data were collected and measured before surgery,after surgery and during follow-up.The patients were divided into groups A,B,and C according to the fusion angle.Spearman correlation was used in the correlation analysis between the occipital-cervical fusion angle and the curvature of the lower cervical spine was performed.Results Among the 28 patients,there were 12 males and 16 females;the age was(38.5±12.4)years;the follow-up time was(158.25±62.34)months.The OC2A fixation angle of 5 patients in group A was within 10°,and the OC2A value of the 5 patients after operation was statistically significant at 6 months after operation,5 years after operation and at the last follow-up(P<0.01).The 4 patients in group C were fixed above 20°,and the differences in C2-C7 Cobb angle were statistically significant at 6 months after operation,5 years after operation and at the last follow-up(P<0.01).In group C,the OC2A value was negatively correlated with the C2-C7 Cobb angle(r=-0.797,P<0.01).Conclusion OC2A has a significant correlation with the C2-C7 Cobb angle,and an appropriate one should be selected when performing posterior occipital-cervical fixation and fusion.The occipital-cervical fusion angle should be within 20°for OC2A.An OC2A exceeding 20°may cause long-term degeneration of the lower cervical spine or even reverse arch.