problems in the body's anatomy can affect its proper functioning. Another tenet is the body's innate ability to heal itself. Many of osteopathic medicine's manipulative techniques are aimed at reducing or eliminating the impediments to proper structure and function so the self-healing mechanism can assume its role in restoring a person to health. Osteopathic medicine defines a concept of health care that embraces the concept of the unity of the living organism's structure (anatomy) and function (physiology). The AOA states that the four major principles of osteopathic medicine are the following: The body is an integrated unit of mind, body, and spirit. The body possesses self-regulatory mechanisms, having the inherent capacity to defend, repair, and remodel itself. Structure and function are reciprocally interrelated. Rational therapy is based on consideration of the first three principles. These principles are not held by Doctors of Osteopathic Medicine to be empirical laws; they serve, rather, as the underpinnings of the osteopathic approach to health and disease. Muscle energy Muscle energy techniques address somatic dysfunction through stretching and muscle contraction. For example, if a person is unable to fully abduct her arm, the treating physician raises the patient's arm near the end of the patient's range of motion, also called the edge of the restrictive barrier. The patient then tries to lower her arm, while the physician provides resistance. This resistance against the patient's motion allows for isotonic contraction of the patient's muscle. Once the patient relaxes, her range of motion increases slightly. The repetition of alternating cycles of contraction and subsequent relaxation help the treated muscle improve its range of motion. Muscle energy techniques are contraindicated in patients with fractures, crush injuries, joint dislocations, joint instability, severe muscle spasms or strains, severe osteoporosis, severe whiplash injury, vertebrobasilar insufficiency, severe illness, and recent surgery. Counterstrain Counterstrain is a system of diagnosis and treatment that considers the physical dysfunction to be a continuing, inappropriate strain reflex, which is inhibited during treatment by applying a position of mild strain in the direction exactly opposite to that of the reflex. After a counterstrain point tender to palpation has been diagnosed, the identified tender point is treated by the osteopathic physician who, while monitoring the tender point, positions the patient such that the point is no longer tender to palpation. This position is held for ninety seconds and the patient is subsequently returned to her normal posture. Most often