Back Muscles Insertion Flashcards
Pectoralis major
Originates from Clavicle and sternum from costal cartilage 1-6 and aponeurosis of external oblique. Inserts into Interubercular groove of humerus for arm extension.
Latissimus dorsi
From T6-12 spinous process, lumbosacral fascia and iliac crest, It attaches to the Biccipital groove of the humerus for ** depression of scapula and adduction.**
It is innervated by the thoracodorsal nerve.
Serratus anterior
Originates from the first 8 ribs and attaches to the medial border of the scapula.
**It protracts scapula and lift it forward.
Innervated by the long thoracic nerve.**
Pectoralis minor
Originates from the costal cartilage 3-5 to insert into coracoid process of scapula.
Causes depression of scapula, innervated by medial pectoral nerve.
Subclavius
Originates from the costachondral rib to insert to the subclavian groove of the clavicle for depressing the clavicle.
Innervated by the subclavius nerve on C5.
Trapezius
External occipital protuberance to spinal process of T12 and spine of scapula to accordion.
** Elevating and retracting the scapula and adduction. It is innovated by the CN XI**
Rhomboid major
Originates from T2-T5 to attach to medial border of scapula for adduction of scapula.
Innervated by the dorsal scapular nerve of C5.
Rhomboid minor
Originates from C7-T1 to attach to medial border to scapula for scapula adduction. Innervated by the dorsal scapular nerve of C5.
What is the attachment of the rhomboid muscles?
Medial border of scapula.
Levator scapulae
Transverse process of C1 to C4 to the superior angle and medial border of scapula to elevate scapula.
Innervated by the dorsal scapular nerve of C5.
Deltoid
3 sets of fibres depending on origin from anterior clavicle, lateral acromion and posterior spinal to attach to deltoid tuberosity on humerus.
Innervated by axillary nerve.
Teres major
Originates from inferior scapula angle to attach to inter tubercular groove of humerus for
**adduction of arm. **
Innervated by the lower subcapsular nerve.
Teres minor
Lateral border of scapula and inserts into the inferior aspect of the greater tuberosity of humerus.
Important for external rotation of the arm, Innervated by axillary nerve.
Supraspinatous
Originates from supraspinatous fossa to the superior aspect of the greater tubercle of the humerus. Involved in abduction of arm.
-> Part of the rotator cuff muscles, innervated by the **supracapsular nerve. **
Infraspinatous
Originates from the infraspinatous fossa to insert into the medial aspect of the greater tuberosity of the humerus.
For external rotation of arm and abduction. Innervated by supracapsular nerve from C5.
Subscapularis
Subscapularis fossa to the lesser tuberosity of the humerus for ** internal rotation of arm.**
Innervated by the upper and lower subcapsular nerve on the posterior cord.
Which rotator cuff muscles are responsible for external rotation?
Infraspinatous and teres minor.
Biceps brachii
Two heads which insert onto the radial tuberosity, innervated by musculocutaneous nerve for elbow flexion.
It has an aponeurosis which attaches and forms the roof of the antecubital fossa.
Where does the long head of biceps arise?
Supraglenoid tubercle which travels down the intertubercular groove of humerus
Where does the short head of biceps arise?
Coracoid process of scapula along with coracobrachialis.
Brachialis
Originates from inferior 1/3 of humerus and inserts into the ulnar tuberosity.
Innervated by musculocutaneous nerve.
Coracobrachialis
From coracoid process and inserts into the medial surface of the humerus midshaft.
Innervated by the musculocutaenous nerve for FLEXION of SHOULDER.
Triceps brachii
Three heads
Originate from infraglenoid tubercle, superior and inferior to humerus radial groove
They have a common attachment to the olecranon of ulna.
Where does long head of triceps arise?
Infraglenoid tubercle
Where does the medial head of triceps arise?
Posterior surface of humerace BELOW radial groove
Where does the short head of triceps arise?
Posterior surface of humerus ABOVE to radial groove
Order of elbow flexors from superficial to deep
Biceps brachii
Brachialis
Coracobrachialis
Role of anterior belly of deltoid muscle
Clavicle to acromion for Flexion of humerus.
Role of middle belly of deltoid muscle
Acromion to clavicle for Abduction of humerus.
Role of posterior belly of deltoid muscle
Goes across the spine of scapula for Extension of humerus.
Which nerve is located near the surgical neck of the humerus?
Axillary nerve
Which nerve is located near the spiral groove of humerus?
Radial nerve
Which nerve is located near the mid axillary line?
Long thoracic
Which nerve is located near the medial epicondyle of the humerus?
Ulnar nerve
Which nerve lies between the long and medial head of triceps?
Radial nerve.
