ected forwards. The hunch-back from Pott's disease is often a
remarkably capable person, both physically and intellectually.

POTT'S DISEASE AS IT AFFECTS DIFFERENT REGIONS OF THE SPINE

#Upper Cervical Region, including Atlo-axoid Disease.#--When the
disease affects the first and second cervical vertebrae, the atlo-axoid
articulation becomes involved, and as a result of the destruction of
its component bones and ligaments, the atlas tends to be dislocated
forward. When this occurs suddenly, the odontoid process may impinge
on the medulla and upper part of the cord and cause sudden death. When
the displacement occurs gradually, the atlas and axis may be separated
to a considerable extent without the cord being pressed upon, and
recovery with ankylosis may ensue. When the third, fourth, and fifth
vertebrae are affected, the tendency to dislocation and compression of
the cord is not so great, but a portion of bone may be displaced
backwards and exert pressure on the cord.

The patient complains of a fixed pain in the back of the neck, and of
radiating pains along the course of the sub-occipital and other
cervical nerves. The neck is held rigid, and to look to the side the
patient turns his whole body round. As the disease advances the head
may be bent to one side as in wry-neck, or it may be retracted and the
chin protruded. To take the weight of the head off the diseased
vertebrae the patient often supports the chin on the hands (Fig. 214).

[Illustration: FIG. 214.--Attitude of patient suffering from
Tuberculous disease of the Cervical Spine. The swelling on the left
side of the neck is due to a retro-pharyngeal abscess.]

An abscess may form between the vertebrae and the wall of the
pharynx--_retro-pharyngeal abscess_--the pus accumulating between the
diseased bones and the prevertebral layer of the cervical fascia. The
abscess may project towards the pharynx as a soft fluctuating
swelling, and may cause difficulty in swallowing and breathing, and
snoring during sleep; if it bursts internally it may cause
suffocation. The abscess may bulge towards one or both sides of the
neck, and come to the surface behind the posterior border of the
sterno-mastoid muscle (Fig. 214). In some cases it comes to the
surface in the sub-occipital region.

If the cord is pressed upon by inflammatory products, there is
muscular weakness, beginning in the arms and extending to the legs,
and sometimes followed by complete paralysis. I