Paralysis is defined as complete loss of strength in an affected limb or muscle group

The four parathyroid glands are small, light-colored lumps protruding from the surface of the thyroid gland. They secrete parathyroid hormone, the most important regulator of calcium and phosphorus amounts in the body.

A pivot joint is a synovial joint in which the ends of two bones meet—one end being a central bony cylinder, the other end being a ring (or ring-like structure) made of bone and ligament. In some joints, the cylinder rotates inside the ring. In other joints, the ring rotates around the cylinder. The rotation of the skull is made possible by a pivot joint. (A synovial joint is the living material that holds two or more bones together but also permits these bones to move relative to each other.)

Reflexes are the body's automatic reaction to some type of sensory stimuli. They involve nerve impulses passing from a receptor to a nerve center and then outward to, for example, a nerve or a gland.

Respiratory failure occurs when the lungs' ability to either add oxygen to the bloodstream or remove carbon dioxide from it is impaired. Respiratory failure can have any one of several causes, such as lung disease or infection, electrolyte imbalance, interruption of the nerve signals that regulate breathing or nervous system damage, structural (rib cage) collapse, or airway obstruction.

Skeletal muscles have transverse striations and are under conscious or voluntary control by the somatic nervous system.

The skeletal system is a living, dynamic, bony framework of the body, with networks of infiltrating blood vessels.

A slightly movable joint (amphiarthrosis) is an articulation between bones in which the motion is limited due to either fibrous tissue or cartilage.

The spinal cord is the elongated bundle of nervous tissue that carries nerve impulses between the brain and the rest of the body. It lies in the vertebral canal of the vertebral column.

The vertebral column is a flexible column, formed by a series of bones called vertebrae. It is part of the axial skeleton and consists of seven cervical, 12 thoracic, five lumbar, five sacral, and four coccygeal vertebrae. Its major function is to enclose and protect the spinal cord and provide structural support to the head and trunk.

Vitamins are organic components in food that are needed for growth and for maintaining good health. They include the fat-soluble vitamins, such as vitamin D, vitamin E, vitamin A, and vitamin K; and the water-soluble vitamins, such as folate (folic acid), vitamin B12, biotin, vitamin B6, niacin, thiamin, riboflavin, pantothenic acid, and vitamin C (ascorbic acid). Vitamins are required in the diet in only tiny amounts, in contrast to the energy components (sugars, starches, fats, and oils).

A wound occurs when the integrity of skin is compromised (e.g., skin breaks, burns, or bone fractures). A wound may be caused by an act, such as a gunshot, fall, or surgical procedure; by an infectious disease; or by an underlying condition.