Send to

Choose Destination
See comment in PubMed Commons below
Eur Spine J. 2013 May;22(5):1142-6. doi: 10.1007/s00586-013-2662-3. Epub 2013 Jan 29.

Morphology of the atlas pedicle revisited: a morphometric CT-based study on 120 patients.

Author information

Xi'an Jiaotong University College of Medicine, Xi'an, Shanxi, People's Republic of China.



To quantify the dimensions of the atlas pedicles and to analyze the relationship between extra medullary height (EMH) with intra medullary height (IMH) of the atlas pedicle.


The images of the patients who had CT scanning and three-dimensional (3D) reconstruction involving atlantoaxial complex between June 2011 and April 2012 and meet our inclusion criteria were studied retrospectively. After reformatting the original images, the EMH and IMH of the atlas pedicles were measured.


Extra medullary height and IMH were, respectively, 4.83 ± 1.13 and 1.29 ± 1.10 mm for males and 3.75 ± 0.93 and 0.60 ± 0.83 mm for females, with statistical difference (P < 0.05). EMH and IMH had some correlation (correlation coefficient r = 0.804) but showed a large variability. Of 240 pedicles of 120 cases, 47.92% (115 pedicles) were ≥1 mm; 12.08% (29 pedicles) were between 0 and 1 mm; and 40% (96 pedicles) were 0.


The EMH and the IMH of the atlas pedicles were measured by using CT images of the atlas, providing anatomic parameters for surgery. They showed a certain correlation but with a high variability. C1 pedicle screw fixation was well performed when the medullary canal was ≥1 mm, but the surgical procedure should be careful when it was between 0 and 1 mm, and avoided when there was no medullary canal in the atlas pedicle! So 3D CT reconstruction should be conducted to obtain data and establish individualized fixation strategy preoperatively.

[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Springer Icon for PubMed Central
    Loading ...
    Support Center