OBJECTIVE: To reveal the relation between alignments of upper and subaxial cervical spine and deduce the optimal atlantoaxial fusion angle by a radiological study. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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°.
OBJECTIVE: To reveal the relation between alignments of upper and subaxial cervical spine and deduce the optimal atlantoaxial fusion angle by a radiological study. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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°.
Authors: Subaraman Ramchandran; Themistocles S Protopsaltis; Daniel Sciubba; Justin K Scheer; Cyrus M Jalai; Alan Daniels; Peter G Passias; Virginie Lafage; Han Jo Kim; Gregory Mundis; Eric Klineberg; Robert A Hart; Justin S Smith; Christopher Shaffrey; Christopher P Ames Journal: Eur Spine J Date: 2017-11-28 Impact factor: 3.134
Authors: Peter Gust Passias; Haddy Alas; Nicholas Kummer; Peter Tretiakov; Bassel G Diebo; Renaud Lafage; Christopher P Ames; Breton Line; Eric O Klineberg; Douglas C Burton; Juan S Uribe; Han Jo Kim; Alan H Daniels; Shay Bess; Themistocles Protopsaltis; Gregory M Mundis; Christopher I Shaffrey; Frank J Schwab; Justin S Smith; Virginie Lafage Journal: J Craniovertebr Junction Spine Date: 2022-09-14
Authors: H Koller; C Ames; H Mehdian; R Bartels; R Ferch; V Deriven; H Toyone; C Shaffrey; J Smith; W Hitzl; J Schröder; Yohan Robinson Journal: Eur Spine J Date: 2018-11-27 Impact factor: 3.134