520 THE THORAX AND VERTEBRAL COLUMN 



nerves leads to reflex phenomena. Pain is experienced over 

 the cutaneous distribution of the second cervical nerve (Fig. 72) 

 the first cervical nerve has no cutaneous branches and the 

 head is kept rigid owing to muscular spasm. 



If the transverse ligament is destroyed or the dens eroded, 

 the head slips forwards and the spinal medulla (spinal cord) is 

 crushed. Death results as the injury occurs above the level of 

 the origin of the phrenic nerve (p. 530). 



When the body of the third or fourth cervical vertebra is 

 the site of the disease, the same rigidity from muscular spasm 

 is present, and pain is experienced over the cutaneous 

 distribution of the third and fourth cervical nerves. These 

 symptoms are due to pressure on the nerves themselves as they 

 pass out from the vertebral canal, unless the joints between 

 the articular processes are involved, in which case they may be 

 entirely reflex. 



Vertebral Caries. In abscess formation, the pus may 

 escape to one or other side of the anterior longitudinal ligament, 

 which connects the anterior surfaces of the vertebral bodies to 

 one another, or it may perforate the ligament. It then gives 

 rise to a retro-pharyngeal abscess, which can readily be recognised 

 on palpation of the posterior wall of the pharynx with the 

 finger. The abscess destroys the longus colli and comes to lie 

 behind the prevertebral fascia. It may extend laterally (p. 113) 

 into the floor of the posterior triangle (Fig. 36), and its sub- 

 sequent course is described on p. 114. 



The abscess may be approached through an incision along 

 the posterior border of the sterno-mastoid, which is retracted 

 forwards along with the carotid sheath (Chiene). The anterior 

 tubercles on the transverse processes are palpated and the 

 abscess is opened, slightly to their medial side, by Hilton's 

 method (cf. evacuation of acute retro-pharyngeal abscess, 

 p. 114). 



When the disease involves the lower cervical and 

 upper thoracic vertebrae, the affected part of the vertebral 

 column is held rigid by muscular spasm. Referred pain is 

 experienced in the upper limbs (Fig. 14) and its distribution 

 may help to determine the precise site of the disease. In 

 advanced cases angular curvature may be present. When an 

 abscess forms, the pus tends to track downwards behind the 

 anterior longitudinal ligament or the prevertebral fascia into 

 the mediastinum. Following the course of the dorsal branch 



