Muscles of The Upper Limb Flashcards
muscle groups in the upper limb
- Muscles connecting Upper Limb with Thoracic wall (muscles of pectoral region)
- Muscles connecting Upper Limb with Vertebral column ((back muscles*)
- Muscles connecting Scapula with humerus (muscles of the shoulder region)
- Muscles of The arm (Anterior & Posterior)
- Muscles of The Forearm (Anterior & Posterior)
- Muscles of The Hand
Muscles of the pectoral region
- Pectoralis Major
- Pectoralis Minor
- Serratus Anterior
Pectoralis Major origin and insertion
origin:
clavicular head (anterior border of medial ⅔ of clavicle)
sternocostal head (Anterior surface of sternum, The upper 6 costal cartilages)
insertion: Lateral lip of the bicipital groove
pectoralis major nerve supply
medial and lateral pectoral nerves
pectoralis major actions
- adduction and medial rotation of the arm
- flexion of the arm
- The sternocostal head, with the arm raised and fixed, can raise the trunk as in climbing
**All Muscles Attached to Bicipital groove*
Adduct and Medially rotate the arm
Pectoralis Minor Origin and insertion
Origin: from outer surfaces of 3rd, 4tg and 5th ribs close to their costal cartilages
Insertion: Coracoid process of the scapula
Pectoralis minor nerve supply
medial pectoral nerve
Pectoralis Minor action
- Protraction of the scapula
- Depression of the shoulder
- If the scapula is fixed, it elevates the ribs
Serratus Anterior Origin and Insertion
Origin: the side of the chest from the upper 8 ribs (6?)
insertion: the entire length of the anterior aspect of the medial border of the scapula
Serratus Anterior nerve supply
nerve to surratus anterior (long thoracic nerve)
Action of Serratus Anterior
- Protraction of the scapula
- rotation of the scapula upward during raising the arn above the head
Serratus Anterior Paralysis
also known as winging of the scapula
what are the muscles connecting the upper limb with vertebral column
trapezius and the latissimus dorsi
trapezius nerve supply and action
nerve supply: Spinal accessory nerve
action: elevates the shoulder
latissimus dorsi nerve supply and actions
nerve supply: thoracodorsal nerve
actions:
1. adduction and medial rotation
2. extension of the arm
(swimming)
what muscles connect the scapula with humerus
muscles of the shoulder:
deltoid
supraspinatus
subscapularis
deltoid nerve supply and actions
nerve supply: axillary nerve
action: middle fibers Abductor of the arm (15⁰ -90⁰)
symptoms of deltoid muscle paralysis
atrophy of the shoulder
unable to abduct the arm to 90⁰
supraspinatus nerve supply and actions
nerve supply: suprascapular nerve
action: initiates abduction of the arm (from 0-15⁰)
subscapularis nerve supply and actions
nerve supply: upper amd lower subscapulaf nerves
action: adduction and medial rotation of the arm
muscles of the arm
front: (bbc)
1. corachobrachialis
2. Biceps Brachii
3. Brachialis
they are all supplied by Musculotaneous nerve and they are flexors
Back:
Triceps
Its supplied by radial nerve, and it is an extensor
coracobrachialis nerve supply and action
nerve supply: musculocutaneous nerve
action: flexion of the arm
biceps brachii has 2 heads (?)
short (medial) head
long (lateral) head [with the capsule of the shoulder joint]
nerve supply and actions of biceps brachii
nerve supply: musculocutaneous nerve
actions:
1. Flexion of the arm
2. Flexion of the elbow
3. Supinator of the semi-flexed forearm
Brachialis nerve supply and action
nerve supply: musculocutaneous nerve (its lateral fibers are supplied by the radial nerve)
action: main flexor of the forearm
the Triceps brachii has 3 heads (?)
long, lateral and medial heads
triceps brachii nerve supply and action
nerve supply: radial nerve
action: main extensor of the forearm
