English: Pelvis Medical: Pelvis
Anatomy
The pelvis is the part of the body above the legs and below the abdomen. In humans, a distinction is made anatomically between a large (pelvis major) and a small pelvis (pelvis minor). The pelvis contains the bladder, rectum and sexual organs; in women, the uterus, vagina and fallopian tubes; in men, the prostate.
At the same time, the term “pelvis” is also used for the bones in this region of the body, which consists of the two hip bones (Ossa coxae) and together with the sacrum (Os sacrum) forms the so-called pelvic girdle or pelvic ring. The pelvic ring, as a component of the human skeleton, connects the spinal column to the lower extremities via the sacroiliac joint (sacroiliac joint) and the hip joint. Due to its stability, the pelvis gives the person a secure stand and an upright posture.
Hip bone
Anatomically, the right and left hip bone are located in the pelvis, each of which is composed of three parts, the ilium (Os ilium), the pubic bone (Os pubis) and the ischium (Os ischii). These three bones are created separately during childhood development so that the pelvis can grow symmetrically with the body and merge with each other around the age of 15 in the area of the acetabulum to form the now uniform hip bone. The acetabulum forms the hip joint with the head of the femur.
Since this joint is exposed to heavy loads throughout its life and wears out over the years, older people often experience complaints there. The sacroiliac joint connects the hip bones with the sacrum. This joint is very tight and can hardly move at all, but plays an important role in the suspension of the spine.
Due to incorrect posture or injuries, the joint surfaces in the sacroiliac joint can shift against each other, causing severe pain (so-called ISG syndrome). At the front of the bony pelvis, the hip bones connect via a cartilaginous connection, the pubic symphysis (symphysis pubica). This connection plays an important role during pregnancy.
Due to the influence of hormones, the pubic symphysis becomes softer and more flexible, so that the head of the child fits better through the pelvis at birth. The female and male bony pelvis differ in their structure. In women, the two pelvic blades are protruding, while the male pelvis is high, narrow and narrow. The female pelvis entrance is larger and roundish oval, whereas the male pelvis is more heart-shaped. Also the pelvic outlet is wider in the female pelvis.
Symphysis
The term symphysis has two meanings in medicine. In itself, the term symphysis refers to the connection of bones through fibrous cartilage. The symphysis thus falls under the category of “fake joints“, because in real joints there is a bone gap between the bones and not a cartilaginous connection.
Fake joints are in turn divided into synchondroses and symphyses. Synchondroses contain hyaline cartilage, symphyses contain fibrous cartilage. In the body, symphyses are found in:
- The pubic symphysis (called symphysis pubica)
- Intervertebral
- In the lower jaw and
- Sternal
Since the changes of the pubic symphysis play an important role in pregnancy, the pubic symphysis is also often referred to by doctors as symphysis only instead of symphysis pubica.
This is why the word “symphysis” in everyday medical life rather refers to the symphysis pubica than the bone joint. The pelvic symphysis is located between the right and left pelvic bones. The fact that this area is not properly ossified plays a very important role at birth.
This is because the fibrocartilage connection allows the pelvis to expand slightly. Due to the hormonal changes during pregnancy, the fibrous connection changes and thus becomes more flexible. The pelvis can therefore dilate and thus create a larger birth canal.
However, the stretching of the pelvis can also be painful before birth. If the stretching is too strong, the symphysis can become loose, which can also cause severe pain. The symphysis can also rupture at birth, which must be treated after birth with muscle training and a so-called trochanteric belt. The pelvic symphysis also forms the starting point for the straight abdominal muscle, the so-called musculus rectus abdominis. It moves from the ribs, more precisely from the fifth to the seventh rib down to the pubic bone and is known as the “washboard stomach” when trained.
