Gross Lab Practical Flashcards
Pectoralis Major Origin
- Clavicle
- Sternum and upper ribs
- Tendon of the External Oblique muscle
Pectoralis Major Insertion
- Greater Tubercle
2. Inter-Tubercular Groove/Humerus
Pectoralis Major Actions
- ADduction and Medial Rotation of Humerus
- Forced Inspiration by elevating the rib cage when the humerus is fixed
- Clavicular Portion: Flexes Humerus at shoulder joint
- Sternocostal Portion: Extends Humerus at shoulder joint
Pectoralis Major Nerve Supply
Medial Pectoral Nerve
Lateral Pectoral Nerve
Pectoralis Minor Origin
Ribs 3-5
Pectoralis Minor Insertion
Coracoid Process
Scapula
Pectoralis Minor Actions
- Involved with protaction/ABduction of the scapula
2. Elevates ribcage and thus involved with forced inspiration
Pectoralis Minor Nerve Supply
Medial Pectoral Nerve
Subclavius Origin
First Rib
Subclavius Insertion
Subclavian Groove/ Clavicle
Subclavius Action
- Moves clavicle medially
2. Acts as a protective cushion between clavicle and subclavian vessels
Subclavius Nerve Supply
Nerve to the Subclavius
Trapezius Origin
- Superior nuchal line/occiput
- External occipital protuberance
- Ligamentum Nuchae
- Spines of C7-T12
Trapezius Insertions
- Clavicle
2. Acromion Process and Spine of Scapula
Trapezius Actions
- Stabilizes the scapula (holds it in normal anatomical position)
- Upper portion: elevates scapula
- Middle and Lower portions: ADducts scapula; depresses scapula
Trapezius Nerve Supply
Motor: Spinal Accesory nerve (CN XI)
Sensory: C3, C4
Rhomboid Major Origin
Spine/Upper Thoracics
Rhomboid Major Insertion
Vertebral Border/ Scapula
Rhomboid Major Actions
- Elevate and ADducts scapula
2. Helps stabilize scapula
Rhomboid Major Nerve Supply
Dorsal Scapular nerve
Rhomboid Minor Origin
C7 and T1 vertebrae
Rhomboid Minor Insertions
Vertebral border of the Scapula
Rhomboid Minor Actions
- Elevates and ADducts scapula
2. Helps stabilize the scapula
Rhomboid Minor Nerve Supply
Dorsal Scapular Nerve
Levator Scapula Origin
Transverse processes of upper cervical vertebrae
Levator Scapula Insertions
Upper medial border and superior angle of the Scapula
Levator Scapula Actions
- Elevates scapula
- ADducts scapula
- Stabilizes scapula
Levator Scapula Nerve Supply
Dorsal Scapular Nerve
Latissimus Dorsi Origin
- Spines of Lower Thoracic and Lumar Vertebrae
- Thoracodorsal Fascia
- Crest of the Ilium
- Lower Ribs
Latissimus Dorsi Insertion
Intertubercular Groove (Lesser Tubercle)
Latissimus Dorsi Actions
- Extends, adduct and medially rotates the humerus
2. Involved in forced expiration
Latissimus Dorsi Nerve Supply
Thoracodorsal nerve
Serratus Anterior Origin
Upper 8 or 9 ribs
Serratus Anterior Insertion
Vertebral border of the scapula
Serratus Anterior Actions
- ABduction and Protraction of scapula
- Stabilizes the scapula
- Involved with forced respiration (only when humerus is aBducted)
Serratus Anterior Nerve Supply
Long Thoracic Nerve
Deltoid Origin
- Anterior/clavicular portion from clavicle
- Middle/acromial portion from the acromion process of scapula
- Posterior/Spinous portion
Deltoid Insertion
- Deltoid
2. Tuberosity of Humerus
Deltoid Actions
- Anterior portion: Flexes and Medially rotates arm
- Middle portion: ABducts arm
- Posterior portion: Extends and Laterally rotates arm
Deltoid Innervation
Axillary nerve
Supraspinatus Origin
Supraspinous fossa of scapula
Supraspinatus Insertion
Geater tuberosity of the humerus
Supraspinatus Actions
- Initiates ABduction of the arm
- Helps laterally rotate humerus
- Helps stabilize shoulder joint
Supraspinatus Innervation
Suprascapular nerve
Infraspinatus Origin
Infraspinous fossa of the scapula
Infraspinatus Insertion
Greater Tuberosity of the Humerus
Infraspinatus Actions
- Laterally rotates humerus
2. Stabilizes shoulder joint
Infraspinatus Innervation
Suprascapular nerve
Subscapularis Origin
Subscapular fossa of the Scapula
Subscapularis Insertion
Lesser Tuberosity of the Humerus
Subscapularis Actions
- Medially rotates humerus
2. Stabilizes shoulder joint
Subscapularis Innervation
Upper and Lower Subscapular nerve
Teres Major Origin
Inferior angle of the Scapula
Teres Major Insertion
Interbercular groove (lesser tuberosity)
Teres Major Actions
- ADducts humerus
- Stabilizes shoulder joint
- Medially rotates Humerus
Teres Major Innervation
Lower Subscapular Nerve
Teres Minor Origin
Axillary border of the scapula
Teres Minor Insertion
Greater Tuberosity of the Humerus
Teres Minor Actions
- Laterally rotates humerus
2. Stabilizes shoulder joint
Teres Minor Innervation
Axillary nerve
Biceps Brachii Origin
Short head: Coracoid Process of the Scapula
Long Head: Supraglenoid tubercle of the scapula
Biceps Brachii Insertion
- Tuberosity of the Radius
2. Shaft of the Ulna
Biceps Brachii Actions
- Flexion of forearm
2. Supinates the Radius (Prime Mover)
Biceps Brachii Innervation
Musculocutaneous Nerve
Coracobrachialis Origin
Coracoid porcess of the Scapula
Coracobrachialis Insertion
Shaft of the Humerus
Coracobrachialis Actions
- Flex and weak ADduction of arm (shoulder joint)
2. Stabilizes shoulder joint
Coracobrachialis Innervation
Musculocutaneous Nerve
Brachialis Origin
Shaft of the humerus
Brachialis Insertion
Ulnar tuberosity and Coronoid process of the Ulna
Brachialis Actions
Flexes forearm (equal prime mover)
Brachialis Innervation
Musculocutaneous Nerve
Triceps Brachii Origin
Long Head: Infraglenoid tubercle of the Scapula
Lateral Head: Shaft of the Humerus
Medial Head: Shaft of the Humerus
Triceps Brachii Insertion
Olecranon Process of the Ulna
Triceps Brachii Actions
Extension of the forearm
Triceps Brachii Innervation
Radial Nerve
Pronator Teres Origin
- Medial Epicondyle of the Humerus
2. Coronoid Process of the Ulna
Pronator Teres Insertion
Pronator Ridge of the Radius