General Topography of Autonomic Nervous System The nervous system is divided into somatic and autonomic divisions: the somatic division controls predominantly voluntary activities, while the autonomic system regulates involuntary functions. The two divisions develop from the same primordial cells; they…
Peripheral Nerve The main function of the peripheral nerve is to rapidly conduct electrical signals between the central nervous system and end organs. The neuronal cell body is the main functional component that maintains the neuron and produces important structural…
Compression Neuropathies Compression neuropathies occur acutely (e.g., proximal radial nerve palsy, peroneal neuropathy at the fibular hear) or more gradually (e.g., median neuropathy at the wrist, ulnar neuropathy at the elbow). Acute compressive neuropathies typically develop at sites where external…
Cervical Disk Herniation Cervical disk disease is a common disorder, accounting for 1% to 2% of all hospital admissions in the United States. Unlike lumbar disk disease, which is approximately six times more common, cervical disk disease is rarely caused…
Spinal Column The spinal column is built up from alternating bony vertebrae and fibrocartilaginous disks, which are intimately connected by strong ligaments and supported by powerful musculotendinous masses. The individual bony elements and ligaments are described in Plates 3-2 to…
Spinal Cord The spinal cord is the downward continuation of the medulla oblongata. It extends from the upper border of the atlas to end in a tapering extremity, the conus medullaris , opposite the lower border of the first lumbar…
Overview of Cranial Nerves The brainstem is the source of all the cranial nerves and provides sensory, motor, and, through the vagus nerve, parasympathetic preganglionic innervation to the face, head, thorax, and most of the abdominal viscera. Distinct motor and…
Skull: Anterior and Lateral Aspects The anterior, or facial, aspect of the skull is composed of the frontal part of the calvaria (skullcap) above and the facial bones below. The facial contours and proportions are largely determined by the underlying…
Overview of Headaches Headache is one of the most common reasons for consulting a physician and is one of the top three reasons for lost work days. Rather than a disease, headache is a symptom, frequently providing a valuable warning…
Clinical Presentations of Brain Tumors Brain tumors commonly present with symptoms of elevated intracranial pressure or focal neurologic dysfunction. Elevated intracranial pressure can directly result from an enlarging mass or can be secondary to the development of hydrocephalus stemming from…