Download Muscles of the Scapula Muscles of the Upper Limb

Muscles of the Scapula
Stabilize the Scapula – All Insert on the scapula
Muscle/Nerve
Origin
Trapezius –
Spinal accessory nerve (XI)
Ligamentum nuchae and
C7 - T12
Levator Scapulae (Ventralis) –
Dorsal scapular nerve and the anterior rami
of C3 and C4 (lateral branches of cervical
spinal nerves 3-5)
Rhomboids –
Dorsal scapular nerve
Pectoralis Minor –
Medial pectoral nerve (lateral branches of
cervical spinal nerves C7, C8, and T1)
Serratus Anterior (Ventralis) –
Long thoracic nerve
Action
Elevates, retracts (ADducts),
rotates, and depresses the
scapula.
C1 - C4
Elevates the scapula, flexes neck
laterally (lateral side bending),
and rotates the scapula.
C7 - T5
Retracts (ADducts), elevates, and
rotates the scapula
Ribs 3 - 5
Depresses, protracts (ABducts),
and rotates the scapula.
Ribs 1 - 9
Protracts (ABducts) and rotates
the scapula.
Muscles of the Upper Limb
“Rotator Cuff” (SITS) – All Insert on the humerus and originate on the scapula
Muscle/Nerve
Supraspinatus – Suprascapular nerve
Infraspinatus – Suprascapular nerve
Teres Minor – Axillary nerve
Subscapularis – Upper and Lower
subscapular nerves (C5 and C6)
Origin
Supraspinous fossa of scapula
Infraspinous fossa of scapula
Lateral (axillary) border of
scapula (superior 2/3 )
Subscapular fossa of scapula
Action
ABducts the arm (humerus)
Laterally rotates the arm (humerus)
Medially rotates the arm (humerus)
Muscles of the Upper Limb
Move the arm – All Insert on the humerus
Muscle/Nerve
Origin
Deltoid –
Axillary nerve
Lateral 1/3 of the clavicle, acromion,
and spine of the scapula
Pectoralis Major –
Medial and Lateral
Pectoral nerves (C5 - T1)
Latissimus Dorsi –
Thoracodorsal nerve
Teres Major –
Lower Subscapular nerve
Coracobrachialis –
Musculocutaneous nerve
Sternum, costal cartilage of ribs 1-6
(or 7), clavicle, and aponeurosis of the
external oblique muscle
Iliac crest, T7 – T12 , ribs 10-12, and
the lumbar fascia
Lateral (axillary) border of scapula
(inferior 1/3)
Coracoid process of the scapula
Action
Prime flexor and ABdctor of the arm
(humerus). Extends and hyperextends
the arm (humerus); laterally and
medially rotates the arm (humerus).
ADducts, flexes, and medially rotates
the arm (humerus), sternal portion
extends the arm (humerus).
Extends, hyperextends, ADducts, and
medially rotates the arm (humerus).
Extends, ADducts, and medially rotates
the arm (humerus).
Flexes and ADducts the arm (humerus);
stabilizes the shoulder joint.
Muscles of the Forearm
Move the Forearm
Muscle/Nerve
Origin and Insertion
Action
FLEXORS
Brachialis –
Musculocutaneous nerve
Origin: Supraglenoid tubercle and coracoid
process of the scapula
Insertion: radial tuberosity of radius and
bicipital aponeurosis
Origin: Anterior surface of the humerus
Insertion: ulna
Brachioradialis –
Radial nerve
Origin: Supracondylar ridge of the humerus
Insertion: radius
Biceps Brachii –
Musculocutaneous nerve
Flexes the forearm and supinates
(laterally rotates) forearm and wrist
(hand); short head flexes the arm
(humerus).
Flexes the forearm.
Flexes the forearm (stabilizes forearm
for small, quick, movements –
“hammering muscle”).
EXTENSORS
Triceps Brachii –
Radial nerve
Anconeus –
Radial nerve
Origin: Infraglenoid tubercle and shaft of
the humerus
Insertion: ulna
Origin: Lateral epicondyle of the humerus
Insertion: ulna
Extends the forearm;
long head extends and adducts arm
(humerus).
Extends the forearm.
Muscles of the Hand
Move the hand
Muscle/Nerve
PRONATORS:
Pronator Teres –
Median nerve
Pronator Quadratus –
Median nerve
SUPINATORS:
Supinator –
Radial nerve
Biceps Brachii –
Musculocutaneous nerve
Origin and Insertion
Origin: medial epicondyle of the humerus
and coronoid process of the ulna.
Insertion: lateral aspect of the radius at its
midpoint
Origin: distal ¼ of the ulna.
Insertion: distal ¼ of the radius.
Origin: lateral epicondyle of the humerus
and posterio-lateral proximal ulna.
Insertion: anterior proximal radius.
Origin: supraglenoid tubercle and coracoid
process of the scapula.
Insertion: radial tuberosity of the radius
and bicipital aponeurosis.
Action
Pronates (medially rotates) forearm and
wrist (hand); assists elbow flexion.
Pronates (medially rotates) forearm and
wrist (hand).
Supinates (laterally rotates) forearm and
wrist (hand).
Flexes the forearm and supinates
(laterally rotates) forearm and wrist
(hand); short head flexes the arm
(humerus).
Muscles of the Wrist or the Digits
Move the wrist or the digits – All Insert on the carpals or digits
Muscle/Nerve
FLEXORS
Flexor Carpi Radialis –
Median nerve
Flexor Digitorum Superficialis –
Median nerve
Palmaris Longus (human only) –
Median nerve
Flexor Carpi Ulnaris –
Ulnar nerve
Flexor Digitorum Profundus –
½ Median nerve and
½ Ulnar nerve
EXTENSORS
Extensor Carpi Radialis Longus –
Radial nerve
Extensor Carpi Radialis Brevis –
Radial nerve
Extensor Digitorum (Communis) –
Radial nerve
Extensor Digitorum Lateralis
(cat only) – Radial nerve
Extensor Carpi Ulnaris –
Radial nerve
Origin
Medial epicondyle of the
humerus at the common flexor
tendon (*Note: Flexor digitorum
superficialis has a broad origin
that includes parts of the radius
and ulna.)
Proximal 75% of the ulna
Lateral supracondylar ridge of
the humerus
Lateral epicondyle of the
humerus at the common extensor
tendon
Lateral epicondyle of the
humerus
Lateral epicondyle of the
humerus at the common extensor
tendon
Action
Flexes and ABducts the wrist (hand)
Flexes the wrist (hand) and the digits
2-5.
Flexes the wrist (hand).
Flexes and ADducts the wrist (hand).
Flexes the wrist (hand) and the digits
2-5.
Extends and ABducts the wrist (hand).
Extends the wrist (hand) and the digits
2-5.
Extends the digits.
Extends and ADducts the wrist (hand).
Sources:
Louis J.Zanella, The Human Body - An Owners Manual – 1995
Modified by William C. Johnson (Dr. J) – 2008, to be simplified and yet consistent with
Drake et al. -2010. (Most recent update – 8/11/13)