Anatomy 🫀 Flashcards
what are the muscles of the pectoral region?
- Pectoralis major
- Pectoralis minor
- Subclavius
- Serratus Anterior
what is the origin of Pectoralis major?
(2 heads)
Clavicular head:
- anterior surface of the medial half of the clavicle.
Sternocostal head:
- Anterior surface of the sternum.
- Upper 6 costal cartilages.
- Aponeurosis of external oblique.
what is the insertion of Pectoralis major?
lateral lip of bicipital groove
what is the nerve supply of Pectoralis major?
Medial and lateral pectoral nerves
what is the action of Pectoralis major?
Two heads:
1. Adduction & medial rotation of the arm.
2. Accessory muscle of respiration.
3. In climbing, draws body upwards.
Clavicular head:
- Helps in flexion of the arm.
origin of Pectoralis minor
3rd, 4th and 5th ribs close to their costochondral junction.
insertion of Pectoralis minor
Coracoid process.
nerve supply of Pectoralis minor
Medial pectoral nerve
action of Pectoralis minor
- Protraction of scapula.
- Depression of scapula.
- Accessory muscle of respiration.
origin of Subclavius
Superior surface of the 1st rib.
insertion of Subclavius
Groove on the inferior surface of the intermediate third of the clavicle.
nerve supply of Subclavius
nerve to subclavius.
action of Subclavius
- Steady the clavicle during movement of shoulder girdle.
- Acts as a buffer to protect the great vessels and nerves from the bone.
origin of Serratus Anterior
eight fleshy digitations from the outer surface of the upper 8 ribs
insertion of Serratus Anterior
- Into the medial border of scapula.
- Lower 5 digitations: into the inferior angle.
nerve supply of Serratus Anterior
Long thoracic nerve
action of Serratus Anterior
- The chief muscle to protraction of scapula.
- The lower 5 digitations: upward rotation of the scapula (raise the arm above the head).
- Accessory muscle of respiration
what are the muscles of the back?
Superficial:
- Trapezius
- Latissimus dorsi
Deep:
- Levator scapulae
- Rhomboid minor
- Rhomboid major
From head, Neck & Thorax
origin of Trapezius
- External occipital protuberance (skull)
- Superior nuchal line (medial 1/3)
- Ligamentun nuchae
- Spine of C7
- All thoracic spines & their supraspinous ligaments
insertion of Trapezius
Upper fibers: Lateral 1/3 of clavicle (posterior border)
Middle fibers:
- Medial border of Acromion process
- Upper lip of crest of spine of scapula
Lower fibers: tubercle on lower lip of crest of spine of scapula
nerve supply of Trapezius
- Spinalaccessorynerve
- C3-4 (proprioceptive)
action of Trapezius
Upper fibers: elevation of scapula & shoulder
Lower fibers: depression of scapula & shoulder
Middle fibers: retraction of scapula
Upper and lower fibers: act together in upward rotation of scapula
From Thorax, Abdomen & Pelvis
origin of Latissimus dorsi
- Outer lip of iliac crest (post part)
- Thoraco-lumbar fascia
- Lower 6 thoracic Spines & their supraspinous ligaments
- Lower 3-4 ribs
- Back of inferior angle of scapula
insertion of Latissimus dorsi
floor of bicipital groove of humerus
nerve supply of Latissimus dorsi
Thoracodorsal N (N to latissimus dorsi)
action of Latissimus dorsi
- Extension, adduction & medial rotation
- raises body toward arms during climbing
- Help in violent expiratory movements (cough & sneez)
origin of Levator scapulae
transverse processes of upper 4 cervical vertebrae
insertion of Levator scapulae
back of medial border of scapula (from upper angle to the spine)
origin of Rhomboid minor
- Ligamentum nuchae
- Spines of C7 & T1
insertion of Rhomboid minor
Back of medial border of scapula Opposite the spine
origin of Rhomboid major
Spines of 2nd, 3rd, 4th and 5th thoracic vertebrae
insertion of Rhomboid major
back of medial border of scapula from spine to inferior angle
nerve supply of Levator scapulae, Rhomboid minor & Rhomboid major
Nerve to rhomboids (dorsal scapular N (C5)
action of Levator scapulae, Rhomboid minor & Rhomboid major
- Elevation & Retraction of scapula
- Depression of shoulder (downward rotation of scapula)
- Fixation of scapula to thoracic wall
what are the muscles of the front of the forearm (Flexor group)?
Superficial Group
- Pronator teres
- Flexor carpi radialis
- Palmaris langus
- Flexor carpi ulnaris
Middle Group
- Flexor digitorum superficialis
Deep Group
- Flexor digitorum profundus
- Flexor pollices longus
- Pronator quadratus
Origin, insertion, Nerve supply & action of Pronator teres
Origin
- (common flexor origin) from the Front of medial epicondyle
- Has another head from the ulna (deep head)
Insertion
- Middle of lateral surface of radius.
Nerve Supply
- Median nerve.
Action
- Pronation of the forearm
Origin, insertion, Nerve supply & action of Flexor Carpi Radialis
Origin
- (common flexor origin) from the Front of medial epicondyle
Insertion
- 2nd and 3rd metacarpal bones.
Nerve Supply
- Median nerve
Action
- Flexion and abduction of wrist joint
Origin, insertion, Nerve supply & action of Palmaris Longus
Origin
- (common flexor origin) from the Front of medial epicondyle
Insertion
- flexor retinaculum.
- palmar aponeurosis.
Nerve Supply
- Median nerve
Action
- Flexion of wrist joint.
Origin, insertion, Nerve supply & action of Flexor Carpi Ulnaris
Origin
- (common flexor origin) from the Front of medial epicondyle
- Has another head from the ulna (deep head)
Insertion
- pisiform bone
- hamate
- 5th metacarpal bones.
Nerve Supply
- Ulnar nerve
Action
- Flexion and adduction of wrist joint.
Origin, insertion, Nerve supply & action of Flexor Digitorum Superficialis
Origin
- (common flexor origin) from the Front of medial epicondyle
- Has additional origin from the radius and ulna
a) Humero-ulnar head
b) Radial head
Insertion
- Middle phalanges of medial 4 fingers.
Nerve Supply
- Median nerve
Action
- Flexion of metacarpo-phalangeal and proximal interphalangeal (PIP) joints of medial 4 fingers.
Origin, insertion, Nerve supply & action of Flexor Digitorum Profundus
Origin
- anterior and medial surface of ulna
Insertion
- Distal phalanges of medial four fingers.
Nerve Supply
- Medial 1/2: ulnar nerve
- Lateral 1/2: median nerve
Action
- Flexion of all joints of medial four fingers.
Origin, insertion, Nerve supply & action of Flexor Pollicis Longus
Origin
- anterior surface of radius
Insertion
- distal phalanx of thumb
Nerve Supply
- Median nerve
Action
- Flexion of all joints of thumb.
Origin, insertion, Nerve supply & action of Pronator Quadratus
Origin
- Lower part of the front of ulna.
Insertion
- Lower part of the front of radius
Nerve Supply
- Median nerve
Action
- Pronation of radioulnar joint.
what are the muscles of the back of the forearm (Extensor group)?
Superficial:
- Brachioradialis
- Extensor carpi radialis longus (ECRL)
- Extensor Carpi radialis Brevis (ECRB)
- Extensor Digitorum
- Extensor Digiti Minimi
- Extensor Carpi Ulnaris
- Anconeus
Deep:
- Supinator
- Abductor Pollicis Longus
- Extensor Pollicis Brevis
- Extensor Pollicis Longus
- Extensor indicis
Origin, insertion, Nerve supply & action of Brachioradialis
Origin
- Upper 2/3 of lateral supracondylar ridge.
Insertion
- Lower end of radius just above styloid process.
Nerve Supply
- Radial nerve
Action
1. Brings supinated or pronated forearm into midprone position.
2. Flexion of elbow joint in mid prone position.
Origin, insertion, Nerve supply & action of Extensor carpi radialis longus (ECRL)
Origin
- (common extensor origin) from the Front of lateral epicondyle
- Lower 1/3 of lat. supracondylar ridge.
Insertion
- 2nd metacarpal bone
Nerve Supply
- Radial nerve
Action
- Extension & Abduction of wrist joint.
Origin, insertion, Nerve supply & action of Extensor Carpi radialis Brevis (ECRB)
Origin
- (common extensor origin) from the Front of lateral epicondyle
Insertion
- 3rd metacarpal bone
Nerve Supply
- Radial nerve
Action
- Extension & Abduction of wrist joint.
Origin, insertion, Nerve supply & action of Extensor Digitorum
Origin
- (common extensor origin) from the Front of lateral epicondyle
Insertion
- Middle and distal phalanges of medial 4 fingers through their extensor expansion.
Nerve Supply
- Radial nerve
Action
- Extension of the medial 4 fingers
Origin, insertion, Nerve supply & action of Extensor Digiti Minimi
Origin
- (common extensor origin) from the Front of lateral epicondyle
Insertion
- Extensor expansion of little finger
Nerve Supply
- Radial nerve
Action
- Extension of the little finger.
Origin, insertion, Nerve supply & action of Extensor Carpi Ulnaris
Origin
- (common extensor origin) from the Front of lateral epicondyle
- Posterior border of ulna.
Insertion
- 5th metacarpal bone
Nerve Supply
- Radial nerve
Action
- Extension & adduction of wrist joint.
Origin, insertion, Nerve supply & action of Anconeus
Origin
- Back of the lateral epicondyle.
Insertion
- Olecranon process
Nerve Supply
- Radial nerve
Action
- extension of the elbow joint
Origin, insertion, Nerve supply & action of Supinator muscle
Origin
- Supinator crest.
- Supinator fossa.
- Lateral epicondyle.
- Annular ligament.
Insertion
- Upper third of radius.
Nerve Supply
- Radial nerve
Action
- Supination of the forearm.
Origin, insertion, Nerve supply & action of Abductor Pollicis Longus
Origin
- Posterior surface of ulna & radius.
Insertion
- First metacarpal bone.
Nerve Supply
- Radial nerve
Action
- Abduction of the thumb.
Origin, insertion, Nerve supply & action of Extensor Pollicis Brevis
Origin
- Posterior surface of radius
Insertion
- Proximal phalanx of thumb.
Nerve Supply
- Radial nerve
Action
- Extension of the thumb
Origin, insertion, Nerve supply & action of Extensor Pollicis Longus
Origin
- Posterior surface of ulna
Insertion
- Distal phalanx of thumb.
Nerve Supply
- Radial nerve
Action
- Extension of the thumb
Origin, insertion, Nerve supply & action of Extensor indicis
Origin
- Posterior surface of ulna
Insertion
- Extensor expansion of index finger.
Nerve Supply
- Radial nerve
Action
- Extension of the index.
what is the Site of the axilla?
Space between the upper part of the thorax and the upper part of the arm.
what is the shape and characters of the axilla?
- Pyramidal in shape.
- It has apex, base and 4 walls.
what is the direction of the apex of Axilla?
Directed upwards towards the root of the neck.
what are the boundaries of the apex of Axilla?
- It is triangular bony space (cervico- axillary canal) bounded by:
1) Anteriorly: clavicle.
2) Posteriorly: upper border of scapula.
3) Medially: outer border of 1st rib.
what is the direction and boundaries of the (Base) floor of the axilla?
- Directed downwards.
Formed by:
1. Skin of the armpit
2. Axillary fascia.
what are the walls of the Axilla?
anterior, posterior, medial & lateral
what forms the Anterior wall of the axilla?
1) Pectoralis major.
2) Subclavius and pectoralis minor
3) Clavipectoral fascia.
what forms the posterior Wall of Axilla?
1) Subscapularis above.
2) Teres major
3) latissimus dorsi below
what form is the medial wall of the axilla?
1) Upper 4 or 5 ribs with the intercostal muscles between them.
2) Serratus anterior muscle.
what forms the lateral wall of the axilla?
1) Bicepital groove.
2) Biceps brachii.
3) Coracobrachialis
what are the contents of the axilla?
1) Axillary artery.
2) Axillary vein.
3) Axillary lymph nodes.
4) Axillary tail of the breast.
5) Axillary fat and loose areolar tissue.
6) Cords & branches of brachial plexus.
where is the site of axillary lymph nodes?
They are found in the fibro fatty connective tissue of the axilla.
what are the groups of axillary lymph nodes?
- They are arranged in five principal groups:
1) Apical
2) Pectoral
3) Subscapular
4) Humeral
5) Central
what is the definition of Clavipectoral fascia?
Strong fibrous sheet situated under cover of clavicular head of pectoralis major.
what is the site of Clavipectoral fascia?
Occupies the gap between the clavicle and pectoralis minor.
attachment of Clavipectoral fascia
Above
- Splits to enclose the subclavius muscle then attaches to the clavicle.
Below
- Splits to enclose the pectoralis minor muscle then continues downward as the suspensory ligament of the axilla and joins its fascial floor.
what are the structures of the pierce the Clavipectoral fascia?
- Acromio-thoracic artery
- Cephalic vein
- Lateral pectoral nerve
- Lymphatics
what are examples of intermuscular spaces?
- Quadrangular space
- Upper triangular space
- Lower triangular space
what are the boundaries and the contents of the quadrangular space?
Boundaries
- Superiorly: Subscapularis (anteriorly), Teres minor (posteriorly).
- lnferiorly: Teres major.
- Medially: Long head of triceps.
- Laterally: Surgical neck of humerus.
Contents
- Axillary (circumflex) nerve.
- Posterior circumflex humeral vessels.
what are the boundaries and contents of the upper triangular space?
Boundaries
- Superiorly: Subscapularis and teres minor.
- Inferiorly: Teres major.
- Laterally: Long head of triceps.
Contents
- Circumflex scapular artery
what are the boundaries and the contents of the lower Triangular space?
Boundaries
- Superiorly: Teres major.
- Medially: Long head of triceps.
- Laterally: Shaft of the humerus.
contents
- Radial nerve.
- Profunda brachii vessels.
what is the definition of a cubital fossa?
Hollow Triangular space situated in front of the elbow occupying the upper third of the forearm
what are the boundaries of the cubital fossa?
- Lateral border: medial border of brachioradialis.
- Medial border: lateral border of pronator teres.
- Base: imaginary line between the two humeral epicondyles.
what forms the roof of the cubital fossa?
- Skin.
- Superficial fascia containing:
1. Median cubital vein.
2. cutaneous nerves of forearm - Deep fascia and bicepital aponeurosis
what forms the floor of the cubital fossa?
- Brachialis (medially).
- Supinator (laterally).
what are the contents of the cubital fossa?
From medial to lateral:
1. Median nerve.
2. Termination of brachial artery and its bifurcation into Ulnar and Radial arteries
3. Biceps tendon.
4. Radial nerve and its deep branch.
what are the stages of brachial plexus?
- Roots
- Trunks
- Divisions
- Cords
roots of brachial plexus
These are the anterior primary rami of C5, 6, 7, 8, T1.
Trunks of brachial plexus
3 trunks lie in the posterior triangle of the neck, pass laterally over the 1st rib to enter the axilla.
- Upper trunk: formed by C5, 6 roots.
- Middle trunk: formed by C7 root.
- Lower trunk: formed by C8, T1 roots.
Divisions of brachial plexus
Each trunk is divided into anterior & posterior divisions.
Cords of brachial plexus
3 cords lie in the axilla & are related to 2nd part of axillary artery.
- Lateral cord: formed by the anterior divisions of the upper & middle trunks.
- Medial cord: formed by the anterior division of lower trunk.
- Posterior cord: formed by all the posterior divisions.
what is the position of stages of brachial plexus?
Roots & trunks lie in the neck, divisions lie behind the clavicle, cords& branches lie in the axilla.
what are the branches of the brachial plexus?
- From the Roots
- From the Trunks
- From the Cords
branches from the root of brachial plexus
- Dorsal scapular nerve (C5): Nerve to rhomboid.
- Long thoracic nerve (C5, 6, 7): Nerve to serratus anterior.
branches from the trunks of brachial plexus
(only from the upper trunk (C5 & 6))
- Suprascapular nerve: passes through the suprascapular notch to supply supraspinatus & infraspinatus muscles.
- Nerve to subclavius.
branches from the lateral cord of brachial plexus (C5,6&7)
- Lateral pectoral nerve: supplies pectoralis major.
- Lateral root of median nerve.
- Musculocutaneous nerve (C5, 6, 7).