Ling Fong Poh, Chevillotte T, Leglise A, Thompson W, Bouthors C, Le Huec Jean-Charles
Bordeaux University Hospital, CHU Pellegrin, Orthorachis 2, 33076, Bordeaux, France.
Dir Surg Research Lab, Orthospine Department, Bordeaux University Hospital, CHU Pellegrin, Orthorachis 2, 33076, Bordeaux, France.
Eur Spine J. 2018 Feb;27(Suppl 1):8-15. doi: 10.1007/s00586-018-5462-y. Epub 2018 Jan 13.
Cervical spine is part of the spine with the most mobility in the sagittal plane. It is important for surgeons to have reliable, simple and reproducible parameters to analyse the cervical.
This study is a systematic review and a critique of current parameters to help improve the study of cervical spinal balance. We conducted a systematic search of PUBMED/MEDLINE for literature published since January 2014. Only studies written in English and containing abstracts were considered for inclusion. The search performed was: «C7 slope» OR «T1 slope» OR «C2C7 offset» OR «C2C7 lordosis» OR «cervical SVA (sagittal vertical axis)» OR «TIA (thoracic inlet angle)» (Lee et al., J Spinal Disord Tech 25(2):E41-E47, 2012) OR «SCA (spino-cranial angle)». Exclusion criteria were purely post-operative and cadaveric analysis, studies performed with CT scan or MRI, studies on adolescent idiopathic scoliosis, traumatology studies and no standing analysis of the cervical spine. Relevance was confirmed by investigators if cervical parameters was a major criteria of the study.
138 articles were found by the electronic search. After complete evaluation 20 articles were selected. The large majority of papers used the same parameters C2_C7 lordosis, C2-C7 SVA, T1 slope or C7 slope and T1 slope/cervical lordosis mismatch. Janusz reported a new parameter using a retrospective cohort of patient with cervical radiculopathy: the TIA (thoracic inlet angle). Le Huec reported an other new parameter based on a prospective study of asymptomatic volunteer: the spino-cranial angle (SCA). This parameter is highly correlated with the C7 slope and the cervical lordosis. Other studies reported parameters that are more global balance analysis including the cervical spine than cervical spine balance itself.
The most important parameters to analyse the cervical sagittal balance according to the literature available today for good clinical outcomes are the following: C7 or T1 slope, average value 20°, must not be higher than 40°. cSVA must not be less than 40°C (mean value 20 mm). SCA (spine cranial angle) must stay in a norm (83° ± 9°). Future studies should focus on those three parameters to analyse and compare pre and post op data and to correlate the results with the quality of life improvement.
颈椎是脊柱在矢状面活动度最大的部分。对于外科医生而言，拥有可靠、简单且可重复的参数来分析颈椎情况非常重要。
本研究是对当前参数的系统综述和批判性分析，以助力改进颈椎平衡的研究。我们对PUBMED/MEDLINE进行了系统检索，查找自2014年1月以来发表的文献。仅纳入用英文撰写且包含摘要的研究。检索式为：“C7斜率”或“T1斜率”或“C2 - C7偏移”或“C2 - C7前凸”或“颈椎矢状垂直轴（SVA）”或“胸廓入口角（TIA）”（Lee等人，《脊柱疾病与技术杂志》25(2):E41 - E47，2012年）或“脊柱 - 颅骨角（SCA）”。排除标准为单纯的术后及尸体分析、使用CT扫描或MRI进行的研究、青少年特发性脊柱侧凸的研究、创伤学研究以及未对颈椎进行站立位分析的研究。若颈椎参数是研究的主要标准，则由研究者确认其相关性。
通过电子检索找到138篇文章。经过全面评估后，筛选出20篇文章。绝大多数论文使用相同的参数，即C2 - C7前凸、C2 - C7矢状垂直轴、T1斜率或C7斜率以及T1斜率/颈椎前凸不匹配。Janusz使用颈椎神经根病患者的回顾性队列报告了一个新参数：胸廓入口角（TIA）。Le Huec基于对无症状志愿者的前瞻性研究报告了另一个新参数：脊柱 - 颅骨角（SCA）。该参数与C7斜率和颈椎前凸高度相关。其他研究报告的参数更多是关于包括颈椎在内的整体平衡分析，而非颈椎平衡本身。
根据目前可得文献，对于良好临床结果而言，分析颈椎矢状面平衡的最重要参数如下：C7或T1斜率，平均值为20°，不得高于40°。颈椎矢状垂直轴（cSVA）不得小于40°C（平均值为20毫米）。脊柱 - 颅骨角（SCA）必须保持在正常范围（83°±9°）。未来的研究应聚焦于这三个参数，以分析和比较术前及术后数据，并将结果与生活质量改善情况相关联。
