the upper limb - pdfs.semanticscholar.org · surface anatomy m. triceps brachii caput longum,...
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The upper limb
Muscles That Move the Pectoral Girdle
Originate on the axial skeleton and insert on the clavicle and scapula.
Stabilize the scapula and move it to increase the arm’s angle of movements.
Some of the superficial muscles of the thorax are grouped together according to the scapular movement they direct.
elevation, depression, protraction, or retraction
The muscles of back Superficial group
Trapezius
Latissimus dorsi
Levator scapulae
Rhomboideus
Deep group
Erector spinae
Splenius
Thoracolumbar fascia
The muscles of thorax Extrinsic muscles
Pectoralis major
Pectoralis minor
Serratus anterior
Intrinsic muscles
Intercostales externi
Intercostales interni
Intercostales intimi
The Muscles of Upper Limb
Muscles of shoulder
Deltoid
supraspinatus
Infraspinatus
Teres minor
Teres major
subscapularis
Major muscles of upper limb
Deltoid
Origin: lateral third of clavicle, acromion, and spine of scapula
Insertion: deltoid tuberosity of humerus
Action: abducts,flexes and medically rotates, extends, and laterally rotates arm
Teres major
Origin: dorsal surface of inferior angle of scapula
Insertion: crest of lesser tubercle of humerus
Action: medially rotates and adducts arm
Foramen axillare laterale et mediale
Arm Muscles That Move the Shoulder/Elbow Joint
(Flexor) compartment
Posterior (extensor) compartment
Anterior compartment
primarily contains shoulder/elbow flexors
Posterior compartment contains elbow extensors
the principal flexors biceps brachii, brachialis, and brachioradialis
muscles that extend the elbow joint triceps brachii and the anconeus
Muscles of arm
Antererior group
Biceps brachii
Coracobrachialis
Brachialis
Posterior group – triceps brachii
Biceps brachii Origin: long head,
supraglenoid tubercle; short head, coracoid process
Insertion: radical tuberosity Action: supinator of forearm,
flexor of elbow joint, weak flexor of should joint
Pronator teres Origin: medical epicondyle of
humerus and deep fascia of forearm
Insertion: middle of lateral surface of radius
Action: pronation of forearm and flexion of elbow
Triceps brachii
Origin: long head, infraglenoid tubercle; lateral head, above groove for radical n., medical head, below groove for radical n.
Insertion: olecranon of ulna
Action: extends elbow joint), long head can extend and adduct shoulder joint
Surface anatomy
M. triceps brachii
caput longum, medialis, lateralis
Surface elements
Skin thick and movable
Subcutaneous tissue well expressed
n. cutaneus brachii posterior
n. cutaneus brachii lateralis inferior
n. cutaneus antebrachii posterior
Posterior of the arm
Deep structures
А. Fascia brachialis
- Thick, thins distally
B. Neurovascular bundles
1. Upper - in canalis humero-muscularis, between:
- sulcus n. radialis
- medial and lateral head of m. triceps brachii
1.1. n. radialis – lies on the humerus
- n. cutaneus brachii lateralis inerior
- n. cutaneus antebrachii posterior
- rr. musculres
1.2. a. profunda brachii
- a. collateralis media
- collateralis radialis
Lower neurovascular bundle
behind medial epicondyle
n. ulnaris
a. collateralis ulnaris inferior
Elbow region
Anterior elbow
Surface anatomy
Three eminences
Two grooves
Elements
Lateral groove - v. cephalica, n. cutaneus
antebrachii lateralis
Medial groove – v. basilica, n. cutaneus
antebrachii medialis
V. mediana cubiti
Deep structures
А. Muscles
Flexors of forearm – medial eminence
Extensors of forearm – lateral eminence
Brachial muscles, mm. biceps, brachialis –
middle eminence
Deep structures
B. Vessels and nerves
Medial bundle - between m. biceps brachii and pronator
teres
- a.v. brachialis, n. medianus
Lateral bundle - between m. brachialis and
brachioradialis
- n. radialis, a. collateralis radialis, a. recurrens radialis
C. Cubital fossa
Boundaries
- m. brachioradialis (lateral), m. pronator teres (medial)
Content
- tendo m. brachialis, m. biceps brachii, bursa bicipitoradialis
Layers of the elbow
Venous
1 v. cephalica
2 v. basilica
3 v. mediana cubiti
Apponeurotic
1 aponeurosis bicipis
2 tendo m. biceps brachii
Neurovascular
1 a. brachialis
2 n. medianus
Muscle
1 m. supinator
2 m. brachialis
3 tendo m. biceps brachii
Bone
1 humerus
2 radius
3 ulna
Anterior elbow
Arteries of upper limb Axillary artery
Continuation of subclavian artery at lateral border of first rib
Becomes brachial artery at lower border of teres major
Divided into three parts by overlying pectoralis minor First portion, above muscle-gives rise
to thoracoacromial a.
Second portion, behind muscle-gives rise to lateral thoracic a.
Third portion, below muscle-gives rise to subscapular a. divides into throcodorsal a.
and circumflex scapular a.
anterior and posterior humeral circumflex a.;
Brachial artery
Continuation of axillary artery
Divides into radial and ulnar arteries at level of neck of radius
Branches Deep brachial a. accompanies
radial nerve
Superior ulnar collaeral a. accompanies ulnar nerve
Inferior ulnar collateral a.
Radial artery and branches
Radial recurrent a.
Superfical palmar branch
Principal artery of thumb
Ulnar artery and branches
Ulnar recurrent a.
Common interosseous artery
Anterior interossous a.
Posterior interosseous a.
Deep palmar branch
Basilic vein
Arises from the medial side of the dorsal venous rete of hand
Ascends on the ulnar side of forearm to the elbow and then in the medial bicepital brachii furrow to middle of the arm where it pierces the deep fascia and joins the brachial vein or axillary vein
Median cubital vein
links cephalic vein and basilic vein in the cubital fossa. It is a frequent site for venipuncture to remove a sample of blood or add fluid to the blood
The lymphatic drainage of upper limb Lymphatic vessels
Superficial-follow the superficial veins, drain into supratrochlear and axillary lymph nodes
Deep-accompany main vessels, end in axillary lymph nodes
Lymph nodes
Cubital lymph node: lies above medial epicondyle of humerus
Axillary lymph node-arranged in five groups
Axillary lymph nodes Arranged in five groups
Lateral lymph nodes lie around the distal end of axillary vein , receiving drainage from the arm, forearm, and hand
Pectoral lymph nodes lie along lateral thoracic vessels, receive afferents from anterior thoracic wall including central and lateral portion of mamma
Subscapular lymph node along subscapular vessels, receive lymph from nape and scapular region
Efferents above three groups pass to central lymph node
Brachial plexus Formation: Five roots: anterior rami of C5-C8
and T1 spinal nerves, roots C5-C7give rise to long thoracic n.
Three trunks Upper trunk formed by the joining of
roots C4,C5,C6. Middle trunk continuation of root C7. Lower trunk formed by the joining of
roots C8 and T1.
Six divisions: above clavicle, trunks form anterior and posterior divisions
Three cords: below clavicle, divisions form three cords that surround the second portion of axillary a.
Position:
passes through the scalene fissure to posterosuperior of subclavian artery, then enters the axilla to form lateral, medial and posterior cords
Main branches Lateral cord
Musculocutaneous n.
Lateral root to median n.
Medial cord
Medial root to median n.
Ulnar n.
Medial brachial cutaneous n.
Medial antebrachial cutaneous n.
Posterior cord
radial n.
axillary n.
thoracodorsal n.
Musculocutaneous nerve
Supplies:
Muscles -‘BBC nerve’
Biceps brachii,
Brachalis
Coracobrachialis;
skin on the anterior aspect of forearm
Median nerve Supplies:
Flexors of forearm except brachioradialis,
Flexor carpi ulnaris
flexor digitorum profundus - ulnar half
Thenar except adductor pollicis, two lateral lumbricals;
Skin of thenar, central part of palm, palmar aspect of radial three and one-half fingers, including middle and
distal fingers on dorsum
Injury: Ape hand
produces sign of benediction, the index and middle fingers cannot be flexed and the thumb cannot be opposed
Ulnar nerve
Supplies:
flexor carpi ulnaris,
ulnar half of flexor digitorum profundus,
hypothenar muscles, interossei,
3rd and 4th lumbricals and adductor pollicis;
skin of hypothenar, palmar surface of ulnar one and one-half fingers, ulnar half of dorsum of hand, posterior aspect of ulnar two and one-half fingers
Injury: claw hand
Radial
Supplies:
Extensor muscles of arm and forearm,
Brachioradialis;
skin on back of arm, forearm, and radial side of dorsum of hand and radial two and one-half fingers
Injury: Wrist drop
Axillary nerve
Supplies:
Deltoid and teres minor muscle;
skin over deltoid and upper posterior aspect of arm
Injury:
deltoid and teres minor paralysis (loss of shoulder abdution and wheel external rotation)
loss of sensation over the deltoid
Forearm Muscles
Supinate and Pronate Supinator muscle supinates the forearm. Biceps brachii supinates the forearm. Pronator teres and pronator quadratus pronate the forearm.
Move the Wrist Joint, Hand, and Fingers
Muscles in the forearm move the hand at the wrist and/or the fingers.
Extrinsic muscles of the wrist and hand originate on the forearm, not the wrist or hand.
Tendons of forearm muscles typically are surrounded by tendon (synovial) sheaths and held adjacent to the skeletal elements by strong fascial structures.
At the wrist, the deep fascia of the forearm forms thickened, fibrous bands termed retinacula.
The forearm extends
from elbow to wrist.
It posses two bones
radius laterally & Ulna
medially.
The two bones are
connected together
by the interosseous
membrane.
This membrane
allows movement of
Pronation and
Supination while the two bones are
connected together.
Also it gives origin for the deep muscles.
Sheath of deep fascia attached to the posterior border of the ulna .
The fascial sheath, interosseous membrane & fibrous intermuscular septa, divide the forearm into 3 compartments, each having its own muscles, nerves, and blood supply.
Fascial Compartments of the Forearm
I-Superficial: 4
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
II-Intermediate: 1
Flexor digitorum superficialis
These muscles: 8 Act on the elbow & wrist joints and those of the fingers. Form fleshy masses in the proximal part and become tendinous in the distal part of the forearm. •Arranged in three groups:
III- Deep: 3
Flexor digitorum profundus
Flexor pollicis longus
Pronator quadratus
FLEXOR GROUP
Superficial Flexors:
They arise - more or less- from the common flexor origin (front of medial epicondyle).
All are supplied by median nerve except one, flexor carpi ulnaris, FCU (ulnar).
All cross the wrist joint except one, pronator teres, (PT).
Muscles of forearm Superficial layer
Brachioradialis
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
common flexor origin (front of medial epicondyle)
supplied by median nerve except flexor carpi ulnaris
All cross the wrist joint except pronator teres
Second layer
Flexor digitorum superficials
Origin:
Common flexor origin,
Coronoid process of ulna;
Anterior surface of radius
Insertion:
Base of middle phalanges of 2nd to 5th fingers.
Action:
Flexes middle and proximal phalanges of 2nd to 5th fingers, and the hand
Third layer
Flexor digitorum profundus
Flexor pollicis longus
Fourth layer Pronator quadratus
Action: flex radiocarpal joint and fingers, pronate forearm
Lateral compartment (3) Brachioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Common extensor origin, (front of lateral epicondyle of the humerus), EXCEPT, 2 (BR & ECRL).
Cross the wrist EXCEPT brachioradialis.
Supplied by deep branch of radial nerve
Posterior compartment (8)
Superficial layer (3)
Extensor digitorum
Extensor digiti minimi
Extensor carpi ulnaris
Common extensor origin, (front of lateral epicondyle of the humerus),
Cross the wrist.
Supplied by deep branch of radial nerve
Deep layer (5)
Supinator
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
Extensor indicis
Action: extend radiocapral joint and fingers, and supinate forearm
Extensor carpi radialis brevis:
base of 3rd metacarpal bone.
Extensor digitorum:
Extensor expansion of the
medial 4 fingers.
Extensor digiti minimi:
Extensor expansion of the
little finger.
Extensor carpi ulnaris:
Base of the 5th metacarpal
bone.
INSERTION
Supination
and
pronation
It occurs in the superior
and inferior radioulnar
joints;
Muscles produce
supination
Biceps brachii.
Supinator.
Muscles produce
pronation
Pronator teres.
Pronator quadratus.
NB. Brachioradialis put
the forearm in midprone-
position.
Human hand – masterpiece of art
Muscles of hand (palm)
Lateral group thenar (4) Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollicis
Adductor pollicis
Action: flex, abduct, adduct and oppose thumb
Medial group hypothenar (3) Abductor digiti minimi
Flexor digiti minimi brevis
Opponens digiti minimi
Action: flex, abduct , and oppose little finger
Intermedial group
Lumbricals (4) flex fingers at MP joints; extend fingers at IP joints
Palmar interossei (3) adduct fingers towards middle finger at MP joints
Dorsal interossei (3) abduct fingers away from middle finger at MP joints
Arteries of upper limb Axillary artery
Continuation of subclavian artery at lateral border of first rib
Becomes brachial artery at lower border of teres major
Divided into three parts by overlying pectoralis minor First portion, above muscle-gives rise
to thoracoacromial a.
Second portion, behind muscle-gives rise to lateral thoracic a.
Third portion, below muscle-gives rise to subscapular a. divides into throcodorsal a.
and circumflex scapular a.
anterior and posterior humeral circumflex a.;
Brachial artery
Continuation of axillary artery
Divides into radial and ulnar arteries at level of neck of radius
Branches Deep brachial a. accompanies
radial nerve
Superior ulnar collaeral a. accompanies ulnar nerve
Inferior ulnar collateral a.
Radial artery and branches
Radial recurrent a.
Superfical palmar branch
Principal artery of thumb
Ulnar artery and branches
Ulnar recurrent a.
Common interosseous artery
Anterior interossous a.
Posterior interosseous a.
Deep palmar branch
Superficial palmar arch
Formed by ulnar artery and superficial palmar branch of radial artery
Curve of arch lies across the palm, level with the distal border of fully extended thumb
Gives rise to three common palmar digital arteries each then divides into two proper palmar digital arteries
Deep palmar arch
Formed by radial artery and deep palmar branch of ulnar artery
Curve of arch lies across upper part of palmar at level with proximal border of extended thumb
Gives rise to three palmar
metacarpal arteries
Veins of the upper limb Deep veins: accompany the arteries of
the same region and bear similar names
Superficial veins
Cephalic vein Arises from the lateral side of the
dorsal venous rete of hand
Ascends on radial side of the forearm to the elbow and then in the lateral side of biceps brachii furrow, continues up the arm in the deltopectoral groove and then to the infraclavicular fossa, where it pierces clavipectoral fascia to drain into axillary vein