The inferior orifice of the small pelvis is uneven, and it is composed of coccygeal tip and sacral tubercle ligament, ischial tubercle, pubic arch and the lower edge of bilateral pubic symphysis, which is rhombic. The part between the upper mouth and the lower mouth is the pelvic cavity.
The pelvis is a disc-shaped bone connecting the spine and the lower limbs, which is connected by the lowest two bones of the spine and the left and right hip bones of the sacrococcygeal bone to form a complete bone ring. The pelvis transfers the weight to the two lower limbs and serves as the base of the free lower limbs. It has the support to protect the organs in the basin, and there are strong ligaments between sacrum and ilium, sacrum and coccyx to form joints.
Generally, you can't move. After pregnancy, under the influence of hormones, ligaments are loose and joints are slightly loose, which is beneficial to delivery.
When the male stands upright, the two anterior superior iliac spines and pubic symphysis are located on the same coronal plane; The anterior superior iliac spine of female leans forward about 65438±0cm. There are obvious gender differences in pelvis, because female pelvis is closely related to pregnancy and delivery.
The difference between male and female pelvis mainly lies in the small pelvis, and the large pelvis also has corresponding manifestations:
The pelvis of women is smaller and lighter than that of men; The traces of muscle, tendon and ligament attachment are not as obvious as those of men; The sacrum base, auricular surface and acetabulum are small, and the pubic symphysis is wide and short.
The absolute values of transverse and sagittal diameters of the upper and lower pelvic openings in women are greater than those in men. Because the pubic body and pubic crest of women are long, the distance from acetabulum to pubic symphysis is larger than the diameter of acetabulum itself. The included angle of pubic arch is above 90, and that of male is 70 ~ 75. In women, the ischial tubercle is slightly everted, and the included angle of the greater ischial notch is larger, so the coccyx is farther back, and the sacral crest is not as significant as that of men.
The artificial pelvis of female pelvis is wider, the hip socket is shallower, the distance between acetabulum on both sides is larger, and the obturator is slightly triangular; The whole pelvis is short and wide.
The pelvis of children and adolescents has not yet been finalized, and the hip bone is not yet a whole. It consists of ilium, phalanges and ischium connected by cartilage. Generally, 19 ~ 24 years old will become a whole. When exercising, girls should avoid jumping from a height to the hard ground, so as to avoid the dislocation and abnormal healing of the three bones, which will affect the normal development and delivery of the pelvis in adulthood.
In addition, girls wearing high heels too early will shift their focus and narrow the pelvic opening. The pelvic morphology of men and women began to differ around the age of 10, with women wide and short, men narrow and long, and the difference was more significant in adulthood.