Unit 1: Superficial Thorax Objectives

jugular fossa

Superficial landmark located between the SCMs and superior to the manubrium

suprajugular fossa

Superficial landmark lateral to the SCMs

deltopectoral groove

A superficial landmark located between the deltoid and pectoralis major muscles.

suprajugular notch

Just inferior to the jugular foss

medial head of the clavicle

The part of the clavicle that is closest to the midline of the body.

sternal angle

bony landmark located at the junction of the manubrium and body of the sternum

xiphoid process

Pointed, inferior end of the sternum.

What are true ribs

Ribs 1-7 that connect directly to the sternum via cartilage.

What are false ribs

Ribs 8-10 cartilage does not connect directly to the sternum.

What are floating ribs

Ribs 11-12 that do not connect to the sternum at all.

What are the three parts of the sternum

Manubrium- most superior part of sternum where collar bone and first pair of ribs attach

Body- inferior to the manubrium, longest section of the sternum, ribs 2-7 attach

Xiphoid process- most inferior portion of the sternum, pointed tip at the bottom

How do the ribs articulate with the thoracic vertebrae

Rib facets articulate with body and transverse processes of thoracic vertebrae, allowing ribs to move up and out while breathing.

Effects of arthritis on costovertebral joints

Causes inflammation, stiffness, and decreases range of motion significantly, resulting in pain during deep breaths, coughing, or twisting.

Origin, insertion, location, action, and innervation of pectoralis major

Origin: medial half of clavicle, sternum, costal cartilages 1-7

Insertion: lateral intertubercular groove

Location:

Action: shoulder adduction, flexion, and medial rotation

Innervation: medial and lateral pectoral nerves

Origin, insertion, location, action, and innervation of pectoralis minor

Origin: Ribs 2 or 3-5

Insertion: Coracoid process of scapula

Location:

Action: shoulder protraction (point with your shoulder)

Innervation: medial pectoral nerve

Origin, insertion, location, action, and innervation of serratus anterior

Origin: upper lateral and posterior 8-9 ribs

Insertion: medial border of the scapula

Location:

Action: protracts and upper rotation of the scapula (raising arm)

Innervation: long thoracic nerve

Origin, insertion, location, action, and innervation of external intercostals

Origin: the inferior border of the superior rib

Insertion: the superior border of the inferior rib

Location:

Action: elevates and expands the inferior rib

Innervation: intercostal nerves

Vein running through the deltopectoral groove

Cephalic vein

Origin: distally

Destination: axillary veins

Blood flow to intercostal muscles

Left side: aorta → subclavian → internal thoracic artery → anterior intercostal artery → posterior intercostal artery → intercostal muscles.

Long thoracic nerve location and innervation

Originates in the brachial plexus and innervates the serratus anterior muscle- runs anterior on the serratus anterior

Lateral pectoral nerve location and innervation

Runs anterior and medial of pectoralis minor- innervates pectoralis major

Medial pectoral nerve location and innervation

Splits the pectoralis minor- innervates pectoralis minor and major