Thoracic and Abdominal Walls

Session 32

Describe the bony structure of the thoracic

cage Describe the structure of the musculature and

neurovasculature of the thoracic and abdominal walls

Analyze the functions of the walls of the thorax and abdomen

Discuss how the structure and function of these walls apply to common dysfunctions

Objectives

Bony structure review

Running in the costal groove:• intercostal artery & vein

(from supreme intercostal & internal thoracic)• intercostal nerve

(from anterior rami)

Bony structure review

Joints of the thorax

External Intercostal (hands in pockEts) Internal Intercostal (hands on tIts) Innermost Intercostal (same as internal)

Intercostals

Right or Left?

Cross section

Intercostal membranes and Transversus thoracis

A patient with a stab wound through the thoracic wall medial

to the midclavicular line will have damage to which

structures?

A. External Intercostal muscle

B. Internal Intercostal muscle

C. Transversus Thoracis

33% 33%33%

Pleura – serous membrane inside the thorax Parietal pleura – superficial Visceral pleura – deep and on the lungs

Pleural cavity – space between parietal and visceral pleura

Right and Left pleural cavities are separated by the mediastinum

Endothoracic fascia, parietal pleura, visceral

pleura

A patient with R pneumothorax will be

unable to breathe because both lungs will be

affected.

A.TrueB.False

True

False

50%50%

Camper’s fascia – contains fatty tissue Scarpa’s fascia – membranous layer between

camper’s fascia and abdominal muscles

Abdominal wall – superficial fascia

External oblique – continuation of external

intercostal (hands in pockEts) Internal oblique – continuation of internal

intercostal (hands on tIts) Tranverse oblique – horizontal fibers, function

to increase intra-abdominal pressure

Posteriorly, all start around the scapular line Anteriorly, all insert at the rectus sheath

(midclavicular line)

Oblique and Transverse Abdominus

Rectus Abdominus

Rectus abdominus is embedded within the rectus sheath

above the arcuate line (between the 2 halves of the internal oblique aponeurosis)

Rectus abdominus is between the rectus sheath and the transversalis fascia below the arcuate line (posterior to the transverse abdominus aponeurosis

Rectus sheath vs. Transversalis fascia

Above or below arcuate line?

Extraperitoneal fascia

What is immediately posterior to Rectus

Abdominus above the arcuate line?

A. Transversalis fascia

B. Aponeurosis of internal oblique

C. Aponeurosis of transverse abd.

D. Parietal peritoneum

Transv

ersalis

fasci

a

Aponeurosis

of intern

al o...

Aponeurosis

of transv

ers...

Parieta

l perit

oneum

25% 25%25%25%

Inguinal Canal

Deep to inguinal ligament Weakest area of

abdominal wall

Myopectineal Orifice

Anterior Abdominal wall – Posterior view

Parietal

peritoneum Visceral

peritoneum Peritoneal folds

Omentum Mesentery

Intra-peritoneal organs vs. Retro-peritoneal organs

Peritoneum

The peritoneal cavity:A. Is a space filled

with fluidB. Is between the

parietal peritoneum and transversalis fascia

C. Contains the abdominal organs

Is a sp

ace fille

d with

fluid

Is betw

een the parie

tal p...

Contains the abdominal

...

33% 33%33%

Inguinal hernias are most likely to severely damage

the femoral nerve

A.TrueB.False

True

False

50%50%

Describe the bony structure of the thoracic

cage Describe the structure of the musculature and

neurovasculature of the thoracic and abdominal walls

Analyze the functions of the walls of the thorax and abdomen

Discuss how the structure and function of these walls apply to common dysfunctions

Objectives