Gross Lab 1: The Thoracic Body Wall

a defined anatomical area of the body containing structures and organs within a distinct boundary

What is the definition of a body region?

head, neck, thorax, abdomen, pelvis, and limbs

What are the main body regions?

the thoracic vertebrae

What is the dorsal boundary of the thorax?

ribs

What is the lateral boundary of the thorax?

the costal arch and the 13th rib

What is the caudal boney boundary of the thorax?

the indirect attachment of ribs 9-12 onto the sternum by an arch or cartilage

What is the costal arch?

the abdominal viscera

What lies immediately caudally to the costal arch?

the diaphragm

What is the muscular bony boundary of the thorax?

manubrium

What is the name for the first thoracic sternebrae?

2

how many layers is skin composed of?

epidermis (outer) and dermis (inner)

What are the two general skin layers?

epithelium

What is the outer layer of skin composed of?

connective tissue

What is the inner layer of skin composed of?

fascia, aponeurosis, tendons, and ligaments

What are the general different forms of connective tissue?

a muscle having only one attachment on the point of reference. these can move one part of the body relative to another part of the body

What is the definition of an extrinsic muscle?

these muscles have both attachments on the point of reference. These can only move one part of the limb relative to another part of the limb

What is the definition of an intrinsic muscle?

of, relating to, or involving a rib

Define costal:

spinous process

What is #1?

intervertebral foramen

What is #2?

transverse process with transverse fovea

What is #3?

small depression

What is a fovea?

a projection from a structure

What is a process?

cranial costal fovea

What is #4?

caudal costal fovea

What is #4'?

body

What is #5?

mammillary process

What is #6?

body

What is #1?

spinous process

What is #2?

transverse process

What is #3?

articular process-cranial

What is #4?

articular process- caudal

What is #5?

lamina vertebral arch

What is #6a?

pedicle vertebral arch

What is #6b?

vertebral foramen

What is #7?

relating to a joint or joints

What does articular mean?

a small rounded part of the bone

What does tubercle?

bellybutton, navel

What does umbilicus?

nipples

What are mammae?

a thin but extensive sheet of skeletal muscle that covers most of the dorsal and lateral walls of the abdomen and thorax.

Where is the cutaneous trunci muscle?

epaxial, extrinsic forelimb, and muscles of ventilation

What are the three functional muscle groups of the thoracic body wall?

they are dorsal to the transverse processes of the vertebrae and function to extend the vertebral column and thus support weight

Where are the epaxial muscles and what is there function?

iliocostalis, longissimus, transversospinalis

What are the three groups of epaxial muscles in the thoracic cavity?

mainly the scapula or humerus

To which bones do the extrinsic forelimb muscles attach?

latissimus dorsi, superficial and deep pectoral muscles, and serratus ventralis

What are the four extrinsic forelimb muscles?

they create a sling which supports the trunk

What is the purpose of the extrinsic forelimb muscles?

superficial pectoral

What muscle is designated by the letter a?

deep pectoral muscle

What muscle is designated by the letter b?

external abdominal oblique

What muscle is designated by the letter c?

latissimus dorsi

What muscle is designated by the letter a?

deep pectoral

What muscle is designated by the letter b?

external abdominal oblique

What muscle is designated by the letter c?

scalenus, internal and external intercostals, and the rectus abdominis, external abdominal oblique

What are the main muscles of ventilation in the thoracic body wall?

the long axis of the limb is defined by a line between digits III and IV

what is a long axis?

facing/ towards the long axis

what does axial mean in reference to the long axis?

facing away from the long axis

What does abaxial mean in reference to the long axis?

refers to the medial rotation of a limb resulting in the palmar and plantar surface of the paw facing ventrally or laterally

What does pronation refer to?

refers to the lateral rotation of a limb resulting in the palmar or plantar surface of the paw facing medially or dorsally

What does supination refer to?

movement away from the median plane

What does abduction mean?

movement toward the median plane

What does adduction mean?

the change of position of the bones that compromise a joint such that the useful angle motion at that joint is reduced

What does flexion mean?

the change of position of the bones that compromise a joint such that the useful angle of motion at that joint is increased

What does extension mean?

cutaneous trunci

What is the most superficial muscle of the thoracic body wall?

lateral thoracic nerve (C8, T1), skin twitching

What nerve innervates the cutaneous trunci and what does that cause?

lies deep to the cutaneous trunci and runs from the transverse processes of the lumbar vertebrae and the thoracolumbar fascia to the teres major tuberosity of the humerus. This extrinsic limb muscle is innervated by the thoracodorsal nerve (C7, C8, T1)

Where does the latissimus dorsi lie and what is it innervated by?

this extrinsic limb muscle us divided into thoracic and cervical parts. It runs from the supraspinous ligament and the median raphe of the neck to the spine of the scapula. The thoracic part is superficial to the dorsal portion of the latissimus dorsi. The trapezius is innervated by the accessory spinal nerve (cranial nerve XI)

Where does the trapezius lie and what is it innervated by?

this extrinsic limb muscle originates from the sternum and inserts on the lesser tubercle of the humerus and on the greater tubercle of the humerus via an aponeurosis. It is innervated by the caudal pectoral nerve (C8, T1)

Where does the deep pectoral muscle lie and what is it innervated by?

this muscle originates from the last six or seven ribs and its fibers run caudoventrally to terminate at the linea alba and prepubic tendon. It functions to maintain the integrity of the abdominal wall and as a muscle of expiration.

Where does the external abdominal oblique lie and what is its function?

cutaneous trunci muscle

What is represented by #1?

latissimus dorsi muscle

What is represented by #2?

trapezius muscle

What is represented by #3?

deep pectoral muscle

What is represented by #4?

external abdominal oblique muscle

What is represented by #5?

brachiocephalicus muscles

What is represented by #25?