Hypertrophy is a term used to define the increased volume of a part of the body. It can affect any part of the body: organ, tissue, cell, or muscle. Hypertrophy may be caused by an overstimulation of a part of the body as in the case of muscle hypertrophy. Hypertrophy in a gland is often associated with an increased secretion. Inflammation may also be involved in this increase in volume. Hypertrophy usually causes a change in the functioning of the tissue.