Feasible and accurate occipitoatlantal transarticular fixation: an anatomic study.
BACKGROUND
Defining the anatomic zones for the placement of occiput-C1 transarticular screws is essential for patient safety.


OBJECTIVE
The feasibility and accuracy of occiput-C1 transarticular screw placement were evaluated in this anatomical study of normal cadaveric specimens.


METHODS
Sixteen measurements were determined for screw entry points, trajectories, and lengths for placement of transarticular screws, as applied in the technique described by Grob, on the craniovertebral junction segments (occiput-C2) of 16 fresh human cadaveric cervical spines and 41 computed tomographic reconstructions of the craniovertebral junction. Acceptable angles for screw positioning were measured on digital x-rays.


RESULTS
All 32 screws were placed accurately. As determined by dissection of the specimens, none of the screws penetrated the spinal canal. Screw insertion caused no fractures, and the integrity of the hypoglossal canal was maintained in all the disarticulated specimens.


CONCLUSIONS
Viable transarticular occiput-C1 screw placement is possible, despite variability of the anatomy of the occipital condyle.
Senoglu
Mehmet
M
Department of Neurosurgery, School of Medicine, Kahramanmaras Sutcu Imam University, Kahramanmaras, Turkey.
Safavi-Abbasi
Sam
S
Theodore
Nicholas
N
Crawford
Neil R
NR
Sonntag
Volker K H
VK
D000328:Adult; D000368:Aged; D001269:Atlanto-Occipital Joint / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery*; D001863:Bone Screws; D002102:Cadaver; D001270:Cervical Atlas / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery*; D004210:Dissection / Q000379:methods; D005260:Female; D005539:Foramen Magnum / Q000033:anatomy & histology / Q000502:physiology / Q000601:surgery; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D016268:Internal Fixators; D007431:Intraoperative Complications / Q000209:etiology / Q000517:prevention & control; D007593:Joint Instability / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D009777:Occipital Bone / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control; D011300:Preoperative Care / Q000379:methods; D013122:Spinal Diseases / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods*; D014057:Tomography, X-Ray Computed