I/A - Exam 2 Flashcards
Supraspinatus M.
Function: abductor of the arm, belongs to the rotator cuff muscle group
Innervation: suprascapular n. (C4-C6)
Infraspinatus M.
Function: lateral rotator of the arm belongs to the rotator cuff muscle
Innervation: suprascapular n. (C5-C6)
Teres minor M.
Function: lateral rotator of the arm. Rotator cuff muscle
Innervation: Axillary (circumflex) n. (C5-C6)
Deltoid m.
Function: most important abductor of the arm up to 90 degrees
Ant. part: flexes (anteversion) the arm + medial rotation of the arm
Middle part: abducts the arm
Post. part: extends (retroversion) + lateral rotation
Subscapularis m.
Function: arm adduction and medial rotation
Innervation: upper & lower subscapular n. (C5, C6, C7)
Pathology: paralysis cause maximal lateral rotation
Teres major m.
Function: arm adduction and medial rotation
Innervation: lower subscapular n. (C6-C7)
Latissimus dorsi m.
(Coughing muscle)
Function: Adduction and medial rotation and extension of the arm
Innervation: thoracodorsal n. (C6, C7, C8)
Coracobrachialis m.
Function: flexion (anteversion) and adduction of arm
Innervation: musculocutaneous n. (C5, C6, C7)
Pectoralis minor m.
Function: Lowers and rotates the scapula
Innervation: medial pectoral n. (C8-T1)
Pectoralis major m.
Function: adduction and medial rotation of humerus
Innervation: lateral and medial pectoral n. (C5-T1)
Serratus anterior m.
(9 heads; 1st-9th rib)
Function: ELEVATION OF ARM OVER 90 DEGREES. Protracts the scapula and holds it against the thoracic wall and rotates the scapula laterally to elevate the arm
Innervation: long thoracic n. (C5, C6, C7)
**Paralysis: winged scapula: lifting the arm beyond 90 degrees is not possible
Differential diagnosis: rhomboid m. injury, here you have winged scapula as well, but arm elevation is normal.
Subclavious m.
Function: pulls the clavicle towards the sternum
Innervation: subclavious n. (C5-C6)
Omohyoid m.
Function: depresses the hyoid, opens the mouth, and helps in the lateral flexion of the head.
*dilates the internal jugular vein lying beneath it, which helps the return of blood to the heart
Innervation: cervical ansa (C1-C3)
Biceps m.
Functions:
Long head: abductor and medial rotator of the arm
Short head: adductor of the arm
Both heads flex (antroversion) shoulder joint
On elbow: flexor and strong supinator of the forearm
Innervation: musculocutaneous n. (C5-C6)
***biceps jerk: C5-C6
Brachialis m.
Function: powerful flexor of elbow joint
Innervation: musculocutaneous n. (C5-C6) and radial n. to some of its lateral part
Triceps m.
Function: chief extensor of elbow joint
Long head acts on two joints: retroversion and adduction of the arm
Innervation: radial n. (C6, C7, C8)
*triceps jerk (C7-C8)
Anconeous m.
Function: assists (extension of elbow) triceps
Innervation: radial n. (C7-C8)
(found between the lateral epicondyle of the humerus and proximal part of the dorsal aspect of ulna
Palmaris longus
Function: flexes the hand toward the palm, tenses the palmar aponeurosis
Innervation: median n. (C7-T1)
Pronator teres
Function: pronation of forearm and flexion at elbow
Innervation: median n. (C6-C7)
Flexor carpi radialis
Function: palmar flexion and radial abduction of hand
Innervation: median n. (C6-C7)
Flexor digitorum superficialis
Function: strong flexors of the fingers (4 medial) joints; also flexes the wrist, runs in the carpal tunnel
Innervation: median n. (C7, C8, T1)
Flexor carpi ulnaris
Function: hand (palmar) flexion and adduction. Runs outside the carpal tunnel
Innervation: ulnar n. (C7-C8)
Flexor digitorum profundus
Function: it is a flexor of the wrist, midcarpal, metacarpophalangeal and phalangeal joints
innervation: median n. laterally (C8-T1), ulnar n. medially (C8-T1)
Flexor pollicis longus
Has its own tendon sheath
Function: flexor of the terminal phalanx (thumb)
Innervation: median n. (C8-T1) interosseous branch
Pronator quadratus
Function: pronates the forearm
Innervation: median n.
Brachioradialis m.
BEER DRINKING MUSCLE.
Function: brings the forearm into midposition between pronation and supination; in this position it acts as a flexor (forearm flexor)
Innervation: radial n. (C5,C6,C7)
Extensor carpi radialis longus
Function: extensor and abduction of hand at wrist joint
Innervation: radial n. (C6-C7)
Extensor carpi radialis brevis
Function: extensor and abductor of the hand at wrist joint
Innervation: radial n. (deep branch) (C7-C8)
Extensor digitorum
Function: extends the 4 medial fingers (metacarpophalangeal joints), strong dorsiflexor of the hand at wrist joint
Innervation: post. interosseous branch of deep radial n. (C7-C8)
Extensor digiti minimi
Function: extension of the 5th digit and dorsiflexion of hand
Innervation: post.
interosseous branch of deep radial n. (C7-C8)
Extensor carpi ulnaris
Function: extends and adducts the hands
Innervation: post.
interosseous branch of deep radial n. (C7-C8)
Supinator m.
Function: encircles the radius and supinates forearm
Innervation: deep branch of radial n. (C5-C6)
Extensor pollicis brevis
Function: extension of the proximal phalanx at metecarpophalangeal joint
Innervation: post. interosseous branch of deep radial n. (C7-C8)
Extensor pollicis longus
Function: extends the thumb using the crest on radius as a fulcrum
Innervation: post. interosseous branch of deep radial n. (C7-C8)
Extensor indicis
Function: index extension and hand dorsiflexion
Innervation: post. interosseous branch of deep radial n. (C7-C8)
Abductor polloicis brevis (thenar muscle)
Function: abduction of thumb
Innervation: median n.
Flexor pollicis brevis (thenar muscle)
Function: flexes thumb
Innervation: superficial innervation is median n., deep head by ulnar n.
Adductor pollicis
Function: thumb adduction
Innervation: deep branch of ulnar n.
Opponens pollicis
Function: thumb opposition
Innervation: median n.
Abductor digiti minimi
Function: abduction of 5th digit
Innervation: deep branch of ulnar n.
Flexor digiti minimi
Function: flexes 5th digit
Innervation: deep branch of ulnar n
Opponens digiti minimi
Function: makes opposition of the 5th finger to thumb possible
Innervation: deep branch of radial n.
Palmar interossei
Function: adduction of digits, assist lumbricals
Innervation: ulnar n.
Dorsal interossei
Function: abduction of digits
Innervation: ulnar n
Lumbricals
Innervation: 2 lateral by median n.
2 medial by ulnar n.
Orbicularis oculi muscle
Function: produces folds in lateral angle of the eye, expression of worry and concern
Innervation: CNVII (facial nerve)
Corrugator supercilli
Function: pulls the skin and eyebrow down and medially. Produces vertical folds. Protects against light. **Pathetic pain muscle
**Thinker’s brow expression
Innervation: CNVIII (facial nerve)
Orbicularis oris m.
Function: its contraction closes the mouth. Strong contraction gives a sucking shape. Expression of reserve
Innervation: CNVII
Buccinator m
Function: enables air to be blown out of the mouth. Pulls angle of the mouth laterally. Keeps the mucous membrane of the cheek free of folds. Contraction gives expression of satisfaction
Zygomaticus major m.
Function: lifts the corner of the mouth upward, giving expression of laughter or pleasure
Innervation: CNVII
Zygomaticus minor m.
Function: aids in zygomaticus major function. Lifts the corner of the mouth upward, giving expression of laughter or pleasure
Innervation: CNVII
Risorious m.
LAUGHING MUSCLE
Function: together with zygomatic major, it produces the nasolabial folds. Its contraction gives expression of action
Innervation: CNVII
Levator labii superioris m.
Function: elevates upper lip
Innervation: CNVII
Levator anguli oris m.
Function: lifts the angle of the mouth, giving expression of self confidence
Depressor anguli oris
Function: pulls the angle of the mouth downwards and produces expression of sadness
Innervation: CNVII
Depressor labii inferioris m.
Function: pulls the lower lid down, giving expression of pereseverance
Mentalis m.
Function: produces chin-lip furrow, giving expression of doubt and indecision
Innervation: CNVII
Platysma m.
Brings down the corners of the mouth, expressing sadness.
Innervation: Facial n. CNVII
Injury to this nerve may lead to paralysis of platysma (skin falls away from neck by folds)
IMPORTANT
Masseter m.
Function: powerfully closes the jaw by elevating the mandible
Innervation: Masseteric n -> CNV/3
Temporalis m.
Function: strongest elevator of lower jaw**
Innervation: Deep temporal n ->CNV/3
Lateral pterygoid m.
Function: mandibular movements (guiding muscle)
Innervation: Lateral pterygoid n -> CNV/3
Medial pterygoid m.
Function: elevates mandible and pushes it forward. Rotational movement.
Innervation: Medial pterygoid n. -> CNV/3
Trapezius m.
Function: elevation, retraction, rotation of scapula. Helps in adduction and slight elevation of arm
Innervation: Accessory n. (CNXI)
Sternocleidomastoid m.
Function: unilateral contraction turns the head to opposite side and bends it ipsilaterally. Bilateral contraction lifts the head. Also functions in respiration.
Innervation: Accessory nerve (CNXI)
Omohyoid m., Sternohyoid m.
Function: fascia tensor and dilates internal jugular vein lying beneath it (this aids in return of blood to the heart). Opens the mouth and helps in lateral flexion of the head
Innervation: cervical ansa (C1-C3)
Sternothyroid m, Thyroid m.
Function: All infrathyroid muscles work together to approximate thyroid cartilage to hyoid bone. When mouth is open, they stabiliza laryngeal cartilages and the hyoid bone.
Innervation: cervical ansa (C1-C3)
Digastric m.
Function: raising hyoid and stabilizing it in speaking and swallowing, depressing the mandible
Innervation: anterior belly by V/3 (trigeminal/mandibular) and posterior belly by VII (facial n.)
Stylohyoid m.
Function: elevates and retracts hyoid bone, elongates floor of the mouth
Innervation: VII, facial nerve (cervical branch)
Myelohyoid m.
Function: elevates hyoid and floor of the mouth and tongue in swallowing and speaking.
Innervation: V/3 (myelohyoid n. from inferior alveolar n.)
Geniohyoid m.
Function: pulls the hyoid anterosuperiorly, shortens floor of the mouth and widens pharynx
Innervation: C1 via hypoglossal nerve
Rectus capitis m.
Function: helps to flex the head
Innervation: cervical plexus (C1)
Longus capitis m.
Function: bend the head forward and unilateral action turns the head sideways
Innervation: cervical plexus (C1-C4)
Longus colli m.
Function: unilateral contraction bends and turns cervical column to the side. Also bend the cervical spine forward
Innervation: cervical and brachial plexus (C2-C8)
Scalene m.
Function: lift the first 2 pairs of ribs (superior part of thorax). Unilateral contraction tilts cervical column to one side
Innervation: brachial plexus (C4-C8)
