Sex Differences of the Pelvis-Pelvic Joints Changes-Changes with Pregnancy-Changes with Age-Sacroiliac Joint Disease-

Sex Differences of the Pelvis

The sex differences of the bony pelvis are easily recognized.

The more obvious differences result from the adaptation of the female pelvis for childbearing. The stronger muscles in the male are responsible for the thicker bones and more prominent bony markings (Figs. 6.1 and 6.4).

■■ The false pelvis is shallow in the female and deep in the male.

■■ The pelvic inlet is transversely oval in the female but heart shaped in the male because of the indentation produced by the promontory of the sacrum in the male.

■■ The pelvic cavity is roomier in the female than in the male, and the distance between the inlet and the outlet is much shorter.

■■ The pelvic outlet is larger in the female than in the male.
 In the female the ischial tuberosities are everted and in the male they are turned in.

■■ The sacrum is shorter, wider, and flatter in the female than in the male.

■■ The subpubic angle, or pubic arch, is more rounded and wider in the female than in the male.

 

Pelvic Joints Changes

Changes with Pregnancy

During pregnancy, the symphysis pubis and the ligaments of the sacroiliac and sacrococcygeal joints undergo softening in response to hormones, thus increasing the mobility and increasing the potential size of the pelvis during childbirth. The hormones responsible are estrogen and progesterone produced by the ovary and the placenta. An additional hormone, called relaxin, produced by these organs can also have a relaxing effect on the pelvic ligaments.

Changes with Age

Obliteration of the cavity in the sacroiliac joint occurs in both sexes after middle age.

Sacroiliac Joint Disease

The sacroiliac joint is innervated by the lower lumbar and sacral nerves so that disease in the joint can produce low back pain and pain referred along the sciatic nerve (sciatica). The sacroiliac joint is inaccessible to clinical examination. However, a small area located just medial to and below the posterior superior iliac spine is where the joint comes closest to the surface. In disease of the lumbosacral region, movements of the vertebral column in any direction cause pain in the lumbosacral part of the column. In sacroiliac disease, pain is extreme on rotation of the vertebral column and is worst at the end of forward flexion. The latter movement causes pain because the hamstring muscles (see page 465) hold the hip bones in position while the sacrum is rotating forward as the vertebral column is flexed

Differences Between the Small and Large Intestine- External Differences--Internal Differences-Liver Trauma-Liver Biopsy-Subphrenic Spaces-

Differences Between the Small and Large Intestine
  External Differences

■■ The small intestine has no fatty tags attached to its wall. The large intestine has fatty tags, called the appendices epiploicae.

■■ The small intestine is mobile( but not the duodenum), whereas the ascending and descending parts of the colon are fixed.

■■ The caliber of the full small intestine is smaller than that of the filled large intestine.

■■ The small intestine (with the exception of the duodenum) has a mesentery that passes downward across the midline into the right iliac fossa.

■■ The longitudinal muscle of the small intestine forms a continuous layer around the gut. In the large intestine (with the exception of the appendix), the longitudinal muscle is collected into three bands, the teniae coli

■■ The wall of the small intestine is smooth, whereas that of the large intestine is sacculated

Internal Differences

■■ The mucous membrane of the small intestine has permanent folds, called plicae circulares, which are absent in the large intestine.

■■ The mucous membrane of the small intestine has villi, which are absent in the large intestine.

■■ Aggregations of lymphoid tissue called Peyer’s patches are found in the mucous membrane of the small intestine; these are absent in the large intestine.

Liver Trauma

 Because The liver is a soft organ, it is a friable structure enclosed in a fibrous capsule. Fractures of the lower ribs or penetrating wounds of the thorax or upper abdomen are common causes of liver injury  because Its close relationship to the lower ribs must be emphasized.. Blunt traumatic injuries from automobile accidents are also common, and severe hemorrhage accompanies tears of this organ. Because anatomic research has shown that the bile ducts, hepatic arteries, and portal vein are distributed in a segmental manner, appropriate ligation of these structures allows the surgeon to remove large portions of the liver in patients with severe traumatic lacerations of the liver or with a liver tumor. (Even large, localized carcinomatous metastatic tumors have been successfully removed.)

 

Liver Biopsy

Liver biopsy is a common diagnostic procedure.  And to reduce the size of the costodiaphragmatic recess and the likelihood of damage to the lung the patient must  holding his or her breath in full expiration—a needle is inserted through the right 8th or 9th intercostal space in the midaxillary line. The needle passes through the diaphragm into the liver, and a small specimen of liver tissue is removed for microscopic examination.

 

Subphrenic Spaces

The important subphrenic spaces and their relationship to the liver are described on page 163. Under normal conditions, these are potential spaces only, and the peritoneal surfaces are in contact. An abnormal accumulation of gas or fluid is necessary for separation of the peritoneal surfaces. The anterior surface of the liver is normally dull on percussion. Perforation of a gastric ulcer is often accompanied by a loss of liver dullness caused by the accumulation of gas over the anterior surface of the liver and in the subphrenic spaces.