Upper Limb Muscular Action Flashcards
What is the action of the Rotator cuff muscles?
- Stabilization of scapula during shoulder joint movement
- Hold head of humerus in glenoid cavity
- Prevent excessive translation of humeral head
- Rotator Cuff muscles
- Supraspinatus
- Infraspinatus
- Teres minor
- Subscapularis
- Clinical
* Inestability of glenohumeral joint
What is the muscular action of Pectoralis minor and Serratus anterior?
- To hold scapula against thoracic wall
- Serratus anterior
- Prime mover
- Ex: pushing a car
What is the muscular action of Trapezius?
- Elevates scapula (shrug shoulders)
- Retract scapula (brace back the shoulders)
- Depress scapula
What is the muscular action of Levator scapulae?
Elevates scapula (Shrugging shoulders)
What is the muscular function of the Rhomboids?
- Retract Scapula (brace back the shoulders)
What muscles are involved in the Abduction of the arm?
- Deltoid
- Main abductor
- Full effective past 15° abduction
- Supraspinatus
- Initates the first 15° from full adduction (assists deltoid)
- Clinical:
- Commonly affected in degenerative tendonitits
- Pain during the first 45° of passive abduction
*Abduction to a right angle with scapula to raise arm above the head causes upward rotation of scapula
- Affects Trapezius and Serratus Anterior
- Gravity allows for downward rotation of scapula
What muscles are involved in the Adduction of the Arm?
- Pectoralis major
- Latissimus dorsi
- Supcapularis
- Teres major
- Coracobrachialis
*All except Coracobrachialis Medially rotates the arm
What muscles are involved in Lateral roation of the arm?
- Infraspinatus
- Teres minor
What are the muscular actions of Pectoralis Major?
- Adduction of arm
- Medial rotation of arm
- Forced inspiration
- Climbing muscles (raise trunk toward arms)
- Flex the Arm
What is the muscular action of the Lastissimus dorsi?
- Adduction of arm
- Medial rotation of arm
- Climbing muscles (raise trunk toward arms)
- Extend arm
What muscles Flex the arm?
- Pectoralis major
- Coracobrachialis
- Deltoid
What muscles Extend the Arm?
- Deltoid
- Latissimus dorsi
What muscles are used for the Flexion of the Forearm?
- Brachialis
* Main flexor - Biceps brachii
- Supinated forearm
- Popeye deformity
- Brachioradialis
* Superficial muscle of posterior compartment
What muscles are used in the Extension of the forearm?
- Triceps brachii
- Anconeus
What muscles are used for Supination of the forearm?
- Supinator (prime mover)
- Biceps Brachii
What muscles are used for Pronation of the forearm?
- Pronator quadratus (prime mover)
- Pronator teres
What muscles are used for Flexion of the hand (at wrist)?
- Flexor carpi radialis
* Tendon is medial to radial artery - Palmaris longus
- Tenses palmar aponeurosis
- Tendon is medial to median nerve
- Flexor carpi ulnaris
- Flexor digitorum superificials
* Flexes middle phalanx (2nd and 5th digits) - Flexor digitorum profundus
* Flexes distal phalanx (2nd and 5th digits)
What muscles are used for Extension of Hand (at wrist)?
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
- Extensor digitorum
* Rupture cause Mallet finger - Extensor digiti minimi
- Extensor carpi ulnaris
- Entensor indicis
What muscles are used for Abduction of the hand (at wrist)?
- Flexor carpi radialis
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
What muscles are used for Adduction of hand (at wrist)?
- Flexor carpi ulnaris
- Extensor carpi ulnaris
What muscles are used for Flexion of the Thumb?
- Flexor pollicis longus
- Flexor pollicis brevis
What muscles are used for Extension of the Thumb?
- Extensor pollicis brevis
- Extensor pollicis longus
What muscles are used for the Abduction of the thumb?
- Abductor pollicis longus
- Abductor pollicis brevis
What muscles are used for the Opposition of the Thumb?
- Opponens pollicis
* Movement at 1st carpometacarpal joint
