710 



DISSECTION OF THE NECK. 



and between 

 atlas and 

 axis. 



Internal 

 ligaments 

 between 

 same bones. 



Dissection 

 of the liga- 

 ments. 



The posterior atlanto-axial ligament^] is also thin, and adherent tcl 

 the dura mater. It closes the interval between the neural arches oij 

 the atlas and axis, and is pierced on each side by the second cervical 

 nerve. 



The ligaments inside the spinal canal are much stronger, and 

 assist in retaining the skull in place during the rotator} 7 and nodding, 

 movements of the head. Between the occipital bone and the second' 

 vertebra are four ligaments a long occipito-axial with a central 

 and two lateral odontoid ; and the odontoid process of the axis is 

 fixed against the body of the atlas by a transverse band. 



Dissection (fig. 253). Supposing the neural arches of the cervical 

 vertebras to be removed except in the first two, the arches of these 

 vertebrae are to be sawn through close to the articular processes. 

 Next, the ring of the occipital bone bounding posteriorly the 



Long 

 occipito- 

 axial 

 ligament. 



FIG. 254. INTERNAL LIGAMENTS BETWEEN THE OCCIPITAL HONK, ATLAS, 

 AND Axis. Second view. (Uourgery.) 



1. Check ligament. 



2. Transverse ligament, sending 

 offsets upwards and downwards. 



3. Cut end of long occipito-axial 

 ligament. 



foramen magnum is to be taken away. Lastly, the student should 

 detach the tube of dura mater from the interior of the spinal canal ; 

 and, by following upwards the posterior common ligament of the 

 bodies of the vertebrae, its continuation, the long occipito-axial 

 ligament will be exposed. 



The long or posterior occipito-axial ligament (fig. 253) is a strong flat 

 band which continues upwards the posterior common ligament of the 

 vertebrae. It is broad above, where it is attached to the upper 

 surface of the basilar process of the occipital bone, reaching outwards 

 on each side as far as the insertion of the check ligaments. Descend- 

 ing thence through the foramen magnum, and over the odontoid 

 process, it becomes somewhat narrower, and is inserted mainly into 

 the back of the body of the axis, but many of the superficial fibres 

 are prolonged into the posterior common ligament. Occasionally a 

 biu*u is found between it and the transverse ligament 



