2 ventral cavities?
2 dorsal cavities?
What are the 2 areas of the thoracic cavity? What does each contain?
- Mediastinum: everything except lung
2. Pleural cavities: lungs in serous membranes
What are the 2 parts of the mediastinum?
- Superior mediastinum
2. Inferior mediastinum
What are the 3 parts of the inferior mediastinum?
- Anterior mediastinum
- Middle mediastinum
- Posterior mediastinum
What divides the superior mediastinum?
Sternal angle = imaginary plane at the joint between two bones of the sternum
What body cavity is the heart found in?
Which is larger: anterior or posterior mediastinum? Why?
Posterior because of vertebrae and diaphragm curvatures
What is in the posterior mediastinum?
- Thoracic duct
- Azygos system
What is in the anterior mediastinum?
Fat tissue left from thymus
What does the sternal angle plane separate?
- Superior and inferior mediastinum
- Trachia branching out into bronchi
- Boundaries of the aortic arch
- Vertebral level between T4 and T5
- Second rib joins sternum
- Azygos vein drains to IVC
What body cavity is the trachea found in?
How to locate the sternum angle on an X-ray?
Locate the trachial bifurcation
Are most X-rays AP or PA?
What 2 views are usually necessary for chest X-rays?
What are the abdominal and pelvic cavities separated by?
Pelvic inlet (rim within pelvic bones)
What are the abdominal and thoracic cavities separated by?
Is there an actual physical border between the abdominal cavity and the pelvis?
What is peritoneum? 2 types?
Very thin film that covers organs in the abdomen:
- Parietal: lines abdominal wall
- Visceral: covers organs suspended in the peritoneal cavity
What are serous membranes?
Tissues that cover organs in 3 areas of the body:
- Pericardium around the heart
- Pleura around the lungs
What are the 2 types of organ peritoneum encasement in the abdominal cavity? Which organs are in a more fixed position?
- Intraperitoneal organs: completely covered by visceral peritoneum and held in peritoneal cavity by double layer of folded peritoneum = mesentery with slippery fluid between them so they don’t stick
- Retroperitoneal organs: positioned between peritoneum and abdominal wall, behind peritoneum (more fixed position)
Describe the inferior portion of the peritoneum.
Goes down through pelvic inlet in pelvic cavity and drapes over pelvic organs which are infraperitoneal (also forms support structures for pelvic organs)
What are the 9 structures that are retroperitoneal?
- Urinary system (kidneys, ureters)
- Adrenal glands
- Aorta and IVC
- Part of rectum
- Most of the pancreas (except for the tail)
- Most of the duodenum (except for the first segment and distal-most portion)
- Ascending and descending colon
- Lymphatic channels
Do both intraperitoneal and retroperitoneal organs have both visceral and parietal peritoneum?
What are greater omentum? Function?
Layers of peritoneum in the abdominopelvic cavity that form skirt-like structures from the stomach to the transverse rectum
Protects the abdominal cavity
What are lesser omentum?
Layers of peritoneum from stomach and duodenum to liver
What 5 structures do folds of peritoneum form in the abdominopelvic cavity?
- Greater omentum
- Lesser omentum
- Peritoneal ligaments
- Covering over pelvic organs
What are the 7 structures that are intraperitoneal?
- Small intestine: jejunum and ileum
- Gall bladder
- Transverse and sigmoid colon
- Cecum and appendix
What structure separates the abdomen into a greater and lesser sac?
The lesser omentum
What are the 5 digestive organs of the abdominal cavity?
- Abdominal esophagus (very short)
- Small Intestine
- Large Intestine
- Rectum and anal canal
3 parts of small intestine? Shortest part?
- Duodenum (shortest)
2 parts of large intestine?
4 parts of colon? Describe each’s location
- Ascending: right side and retroperitoneal
- Transverse: crosses over to left side and intraperitoneal
- Descending: descends inferiorly and retroperotineal
- Sigmoid: back to midline and intraperitoneal
Where is the appendix?
Attached to cecum of large intestine and intraperitoneal
What are the 3 accessory digestive organs of the abdominal cavity? Location?
- Liver: intraperitoneal
- Gall bladder: intraperitoneal
- Pancreas: retroperitoneal
What are the 5 non-digestive organs of the abdominal cavity? Location?
- Spleen: intraperitoneal
- Kidneys (urinary system): retroperitoneal
- Adrenal glands: retroperitoneal
- Aorta/IVC, lymphatics: retroperitoneal
- Appendix: intraperitoneal
Which 2 abdominal organs are solid?
What is the biliary tree?
Division of ducts that drain bile from liver and gall bladder to the duodenum
Where is bile made?
Where is bile stored?
What is the major duodenal papilla?
Portion of duodenum where biliary tree and pancreas secretions enter the duodenum
Divides foregut and midgut
Where are abdominal PREvertebral ganglia and plexuses located in the abdomen?
Around the aorta near the major unpaired branches to the digestive tract (celiac, SMA, and IMA)
What are the 3 types of contents of the pelvic cavity?
What are the contents of the female pelvic cavity? List from anterior to posterior and superior to inferior.
- Urinary: bladder and urethra
- Reproductive: ovaries, fallopian tubes, uterus, cervix, vaginal canal
- Digestive: rectum and anal canal
Are the ovaries attached to the fallopian tubes?
NOPE, they have an opening on the end facing the ovary (are open to the peritoneal cavity)
What keeps the ovaries from floating around in the pelvis?
All held in place by peritoneum draping down
What are the contents of the male pelvic cavity? List from anterior to posterior and superior to inferior.
- Outside pelvic cavity: testes and epididymis and penis with urethra
- Urinary: bladder
- Reproductive: vas deferens, prostate, seminal vesicles
- Digestive: rectum and anal canal
Which is longer: male or female urethra?
What passes through the prostate?
Urethra and ejaculatory duct that connects to urethra
Role of prostate gland?
Produces secretions for ejaculate
Purpose of vas deferens?
Drain sperm internally back to seminal vesicles
What are seminal vesicles?
Paired glands producing semen
Role of pelvic floor?
- Separates pelvic cavity from perineum
- Covers pelvic outlet
- Supports pelvic organs
- Supports anal and urinary sphincters
What is the pelvic floor mostly composed of?
Sling of muscles = pelvic diaphragm made of Kegel muscles
What is the perineum? What does it contain?
Diamond shape area inferior to the pelvic floor (more superficial)
- Muscles (smooth and skeletal)
- Erectile tissue
- External genitalia
- Urethra in females
Is pelvic floor injury more common in males or females? Why?
Because of vaginal delivery of babies
Major innervation of the perineum?
Pudendal somatic nerve
What is pelvic organ prolapse? In what patients does this happen? Treatment?
Pelvic organs come out of the vagina or rectum
In women that have had many children
Treatment: doughnut pessary made of rubber is inserted to help support the pelvic organs
What is the peritoneal cavity?
Space between the parietal peritoneum and visceral peritoneum
Is there a pleura for each lung or are both lungs covered by one big membrane?
One for each