Testicular failure with an onset before the end of childhood prevents the full development of masculine features; the genitalia remain infantile in appearance, and secondary sex characteristics, such as deepening of the voice and pubic, beard, and body hair, do not develop. Epiphyseal fusion is delayed, and long bone growth is proportionately greater than that of the axial skeleton, causing eunuchoidal proportions (see Chap. 115). Deterioration of testicular function after normal puberty decreases sperm and testosterone production, manifesting clinically as the loss of libido, impotence, infertility, reduced hair growth, atrophy of the prostate and other accessory sex organs, and a reduced semen volume if ejaculation is possible (Fig. 116-2). There may be dryness of the skin from reduced sebum production and wrinkling of the skin on the face. Atrophy and depigmentation of the genital skin and hot flushes also may occur, but the latter are less marked symptoms of gonadal failure in men than they are in women. Other features possibly attributable to androgen deficiency include lethargy and weakness with loss of muscle bulk and increased subcutaneous fat on the trunk. Anemia and osteoporosis may result from prolonged androgen deficiency. Gynecomastia commonly accompanies hypogonadism of many causes (see Chap. 120). Spider nevi may be seen with testicular failure unassociated with liver disease or alcoholism, although rarely in large numbers8 (see Fig. 116-2).