<p>Atrophy is defined as the reduction in size or wasting of a muscle. Visualize the whole extremity from the front, side, and behind as muscle groups should be in proportion to each other. Observe and palpate the muscle contour in relaxed and contracted states. A muscle (e.g. biceps) may appear larger on 1 side due to motor dominance. However, if the opposite side muscle has maintained normal physiological contour, the score given should be 0.</p>