The structure of the lower limb is specialized for support of the body’s weight, locomotion and maintenance of body stability (balance). Indeed, adaptations for weight-bearing and stability account for the major structural and functional differences between the upper and lower limbs. The inguinal (pelvicrural) and gluteal (buttock) regions are important anatomical junctional zones between the trunk and the lower limb through which longitudinally running nerves and…

The female reproductive system consists of the lower genital tract (vulva and vagina) and the upper tract (uterus and cervix with associated uterine (Fallopian) tubes and ovaries). Lower Genital Tract Vulva The female external genitalia or vulva (pudendum) include the mons pubis, labia majora, labia minora, clitoris, vestibule of the vagina, vestibular bulbs and the greater vestibular glands (Bartholin’s glands) ( Fig. 75.1 ). Mons pubis…

The male reproductive system includes the gonads, spermatic cord, accessory sex glands and external genitalia. The male gonads, the testes, are responsible for spermatogenesis and steroidogenesis, thereby regulating reproductive function as well as normal physical and sexual development and behaviour. The accessory sex glands include the prostate, seminal glands (vesicles) and bulbo-urethral glands. Prostatic and seminal gland secretions constitute most of the seminal fluid volume, containing…

Urinary Bladder The urinary bladder is a reservoir. Its size, shape, position and relations all vary according to its content and the state of the neighbouring viscera. When the bladder is empty, it lies entirely in the lesser pelvis, but as it distends it expands superiorly into the abdominal cavity ( Video 73.1 ). An empty bladder is somewhat tetrahedral and has a fundus, body, neck,…

Kidney The kidneys excrete end products of metabolism and excess water. These actions are essential for the control of concentrations of various substances in the body, maintaining electrolyte and water balance approximately constant in the tissue fluids. The kidneys also have endocrine functions, producing and releasing erythropoietin, which affects red blood cell formation; renin, which influences blood pressure; 1,25-dihydroxycholecalciferol (the metabolically active form of vitamin D),…

Lesser Pelvis The lesser pelvis is a bowl-shaped structure formed from the sacrum, pubis, ilium, ischium, the ligaments that interconnect these bones, and the muscles that line their inner surfaces. It begins at the level of the plane passing through the promontory of the sacrum, the arcuate line of the ilium, the pecten pubis and the posterior surface of the pubic crest. This plane, or ‘inlet’,…

The suprarenal (adrenal) glands lie immediately superior and slightly anterior to the superior pole of each kidney (see Figure 72.5, Figure 61.8 ). The glands are golden yellow in colour and are enclosed within the renal fascia, where they are separated from the kidneys by a small amount of loose connective tissue. Each gland possesses two functionally and structurally distinct areas: an outer cortex and an…

The spleen is a large, encapsulated, complex mass of vascular and lymphoid tissues situated in the upper left quadrant of the abdominal cavity between the fundus of the stomach and the respiratory diaphragm. It is mainly concerned with phagocytosis and immune responses but is also important in immunological defence, metabolism and maintenance of circulating blood elements ( , ; Table 69.1 ). In the fetus, the…

The pancreas is one of the largest digestive glands. Its primary function is exocrine, secreting enzymes involved in the digestion of lipids, carbohydrates and proteins. It has an additional endocrine function derived from clusters of cells scattered throughout the gland, which take part in glucose homeostasis and the control of upper gastrointestinal tract motility and function. The healthy pancreas is yellow, with a soft to firm…

The biliary tree comprises the system of ducts that collect and deliver bile from the liver to the descending (second) part of the duodenum. It is conventionally divided into intrahepatic and extrahepatic biliary trees. The intrahepatic ducts are formed from bile ductules that join to form segmental ducts. These merge to form right and left hepatic ducts close to the porta hepatis. The extrahepatic biliary tree…

The liver is the largest of the abdominal viscera, occupying a substantial portion of the upper abdominal cavity. It occupies most of the right hypochondriac and epigastric regions and frequently extends into the left hypochondriac region as far as the left anterior axillary line ( Fig. 66.1 ). As the body grows from infancy to adulthood, the liver rapidly increases in size. This period of growth…

The large intestine extends from the ileocaecal junction to the anus ( Fig. 65.1 ). It begins as the caecum and vermiform appendix, which are usually located in the right iliac fossa. The ascending colon passes superiorly in the right lateral region to the right hypochondriac region, where it bends to the left to form the right colic flexure and become the transverse colon. This loops…

Overview The small intestine consists of the duodenum, jejunum and ileum. It extends from the pylorus to the ileocaecal junction and has a mean length of 5 metres (3–8.5 metres) when measured intraoperatively in adults ( ). The duodenum extends from the stomach to the duodenojejunal junction, marked by the suspensory ligament of the duodenum (ligament of Treitz). There is no clear boundary between the jejunum…

Abdominal Part of the Oesophagus The abdominal part of the oesophagus is 1–2.5 cm long, lies to the left of the midline and is slightly broader at the cardiac orifice than at the oesophageal hiatus, which lies at the level of the eleventh thoracic vertebra ( ). It runs obliquely to the left and slightly posteriorly and ends at the gastro-oesophageal junction, where it is continuous…

The peritoneum is the largest serous membrane in the body. In males the peritoneum forms a closed sac, but in females it is open at the abdominal ostia of the uterine tubes. Its smooth appearance is unremarkable, but its conformation varies. Directly beneath the single layer of mesothelium is a well-developed basement membrane, outside which is a rich lymphatic plexus. Microscopic mesothelial pores or peritoneal stomata…

Definitions, Boundaries and Contents The posterior abdominal wall has no agreed uniform definition. It is the posterior boundary of the abdominal cavity, and in common with the anterior and lateral abdominal walls, it is composed of several layers (skin, superficial fascia, muscle, extraperitoneal fat/fascia and parietal peritoneum). The vertebral column and paravertebral muscles are part of the posterior abdominal wall, but are usually discussed as part…

The anterior abdominal wall constitutes a curved hexagonal area defined superiorly by the costal arches (margins) and xiphisternal junction, laterally by the mid-axillary line, and inferiorly by an imaginary line running along the iliac crests, inguinal ligament and pubic symphysis. It is continuous with the posterior abdominal wall and paravertebral tissues, forming a flexible sheet of skin, muscle and connective tissue across the anterior and lateral…

General Structure and Function of the Abdominopelvic Cavity Although often considered separately, the abdomen and pelvis form the largest continuous visceral cavity in the body. Together, they provide multiple vital functions including: housing and protection of the digestive and urinary tracts and of the internal reproductive organs; a conduit for neurovascular communication between the thorax and lower limb; support and attachment for the external genitalia; access…