Parasympathetic supply to the head and neck stems from four parasympathetic ganglia, which receives fibres from CN III, VII and IX. CN X also has parasympathetic function but is mainly concerned with below the neck. Sympathetic (from the superior cervical ganglion) and sensory fibres also pass through the ganglia (without synapsing). They are therefore involved in autonomic control of the eye, salivary glands and lacrimal … Continue reading Parasympathetic innervation of head & neck

A typical vertebra has an anterior body, two pedicles and two laminae which unite to form a ring bone from which a spinous process protrudes posteriorly and two transverse processes protrude laterally. The first and second cervical vertebra, the atlas and axis however, are atypical. The atlas no body, but instead has a short and thick anterior arch and a longer posterior arch (grooved superiorly … Continue reading Atlas & axis (C1, 2)