Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, 415 Fengyang Road, Huangpu District, Shanghai 200003, People's Republic of China.
Arch Orthop Trauma Surg. 2011 Jun;131(6):857-62. doi: 10.1007/s00402-011-1265-x. Epub 2011 Jan 28.
To reveal the relation between alignments of upper and subaxial cervical spine and deduce the optimal atlantoaxial fusion angle by a radiological study.
414 asymptomatic volunteers (213 males, 201 females) underwent cervical lateral radiographs in neutral position. The Oc-C2 angle, C1-C2 angle and C2-C7 angle were measured. Relations among these three angles and relations between angles and age were analyzed.
The mean Oc-C2 angle was 16.3° ± 7.0° in females, significantly larger than 14.9° ± 6.5° in males. The mean C1-C2 angles were 28.2° ± 4.0° in females and 26.4° ± 4.6° in males, and C2-C7 angles were 12.7° ± 6.6° and 16.3° ± 7.3°, correspondingly. The mean C1-C2 angle in females was significantly larger than that in males, while C2-C7 angle smaller than that in males. The C2-C7 angle correlated significantly not only with C1-C2 angle but also with Oc-C2 angle. And correlation between C1-C2 angle and C2-C7 angle was stronger than that between Oc-C2 angle and C2-C7 angle. There were also significant positive correlations between C1-C2 and Oc-C2 angles. Oc-C2 angle, C1-C2 angle, and C2-C7 angle correlated significantly with age in both sexes.
There were negative correlations between C1-C2 angle and C2-C7 angle as well as between Oc-C2 angle and C2-C7 angle, and the former correlation was stronger. C1-C2 fixation angle was the key to regulate postoperative subaxial alignment in atlantoaxial arthrodesis. The optimal atlantoaxial fusion angle may be between 25° and 30°.
通过影像学研究揭示上颈椎和下颈椎矢状位对线之间的关系，并推导出最佳寰枢融合角度。
414 名无症状志愿者（男性 213 名，女性 201 名）接受颈椎中立位侧位片检查。测量 Oc-C2 角、C1-C2 角和 C2-C7 角。分析这三个角度之间的关系以及角度与年龄之间的关系。
女性的平均 Oc-C2 角为 16.3°±7.0°，显著大于男性的 14.9°±6.5°。女性的平均 C1-C2 角为 28.2°±4.0°，男性为 26.4°±4.6°；C2-C7 角分别为 12.7°±6.6°和 16.3°±7.3°。女性的平均 C1-C2 角显著大于男性，而 C2-C7 角小于男性。C2-C7 角不仅与 C1-C2 角显著相关，还与 Oc-C2 角显著相关。C1-C2 角与 C2-C7 角之间的相关性强于 Oc-C2 角与 C2-C7 角之间的相关性。C1-C2 角和 Oc-C2 角之间也存在显著的正相关。Oc-C2 角、C1-C2 角和 C2-C7 角在两性中均与年龄显著相关。
C1-C2 角与 C2-C7 角以及 Oc-C2 角与 C2-C7 角之间存在负相关，且前者的相关性更强。C1-C2 固定角度是调节寰枢融合术后下颈椎对线的关键。最佳寰枢融合角度可能在 25°至 30°之间。
