Transcript Elbow Anatomy - PA

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Elbow Anatomy
Elbow Anatomy - bones
• Humerus
– medial epicondyle
– lateral epicondyle
• Radius
• Ulna
– Olecranon
Elbow Joint
• New seats today
• Complaining is expected
Elbow Region Joints
• 3 Main Joints:
– Humeroulnar Joint =
“true elbow joint”
– Humeroradial Joint
– Proximal Radioulnar
Joint
Humeroulnar Joint
• Synovial Joint Hinge
• Movements:
– Flexion
– Extension
Humeroradial Joint
• Synovial Joint Gliding or Plane
• No real “true”
movement
Proximal Radioulnar Joint
• Synovial Joint - Pivot
• Ligaments:
• Ulnar Collateral
Ligament
• Radial Collateral
Ligament
• Annular Ligament
• Movements:
– Supination
– Pronation
Proximal Radio-Ulnar Joint
Annular Ligament
Medial Collateral Ligament (MCL)
Resists valgus
forces
Limits extension
UCL
Anterior
Medial
Collateral
Ligament
Posterior
Medial
Collateral
Ligament
Transverse ligament
Lateral Collateral
• Resists varus stress
• Weaker than MCL
• RCL
Elbow Movement & Limitations
Elbow Extension
• Concavity (trochlear
notch) of ulna moves on
the trochlea of humerus
• Extension limited by
olecranon process into
olecranon fossa
• No articulartion between
radius and humerus in
elbow extension
Elbow Movement & Limitations
Elbow Flexion
• Coronoid process of
ulna moves into the
coronoid fossa of the
humerus
• The radial head slides
over the capitulum
and enters the radial
fossa
Nerves
• All of the nerves that
travel down the arm
pass across the elbow
• Three main nerves
begin together at the
shoulder: the radial
nerve, the ulnar nerve,
and the median nerve.
• These nerves carry
signals from the brain to
the muscles that move
the arm. The nerves
also carry signals back
to the brain about
sensations such as
touch, pain, and
temperature.
Nerves
• Each nerve travels
through its own tunnel as
it crosses the elbow.
• Because the elbow must
bend a great deal, the
nerves must bend as
well.
• Constant bending and
straightening can lead to
irritation or pressure on
the nerves within their
tunnels and cause
problems such as pain,
numbness, and
weakness in the arm and
hand.
Blood Vessels
• The largest artery is the
brachial artery that travels
across the front crease of
the elbow. If you place
your hand in the bend of
your elbow, you may be
able to feel the pulsing of
this large artery.
• The brachial artery splits
into two branches just
below the elbow: the
ulnar artery and the
radial artery that
continue into the hand.
• Damage to the brachial
artery can be very serious
because it is the only
blood supply to the hand.
Blood Vessels
• basilic vein
• it unites with the Median
antebrachial vein(s) to
form the axillary v.
• basilic v. communicates
with deep veins of the
forearm through
perforating veins,
especially in the cubital
region
Blood Vessels
• Cephalic Vein
• It drains into the
Subclavin Vein
• median cubital vein
usually pushes some
of the blood collected
by the cephalic v. to
the basilic v.
Blood Vessels
• Median Cubital Vein
• Some Blood runs
from the Cephalic
Vein through the
median Cubital into
Basilic Vein
• The Most Common
Vein for
phlebotomists
Muscles
Anconeus
• Origin Lateral epicondyle
of humerus
• Insertion Lateral surface
of olecranon
• Action Assists triceps in
extending forearm;
stabilizes elbow joint;
• Innervation Radial nerve
(C7, C8 and T1)
Anconeus
Biceps Brachii
• Origin
• Short head: tip of coracoid
process of scapula
Long head: supraglenoid
tubercle of scapula
• Insertion Tuberosity of radius
and fascia of forearm via
bicipital aponeurosis
• Action Supinates forearm and,
when it is supine, flexes
forearm
• Innervation
Musculocutaneous nerve (C5
and C6 )
Biceps Brachii
Brachialis
• Origin Distal half of
anterior surface of
humerus
• Insertion Coronoid
process and tuberosity of
ulna
• Action Major flexor of
forearm -- flexes forearm
in all positions primarily
pronated
• Innervation
Musculocutaneous nerve
(C5 and C6)
Brachioradialis
O: Proximal 2/3 of lateral
supracondylar ridge of
humerus
I: Styloid process of radius
N: Radial nerve
A: Flexes forearm after flexion
has been started by biceps,
semipronator and
semisupinator
Brachioradialis
Brachioradialis
Triceps Brachii
• Origin
• Long head: infraglenoid
tubercle of scapula
Lateral head: posterior
surface of humerus, superior to
radial groove
Medial head: posterior surface
of humerus, inferior to radial
groove
• Insertion Olecranon process
of ulna and fascia of forearm
• Action Chief extensor of
elbow
• Long head extends the
shoulder as well
• Innervation Radial nerve (C6,
C7 and C8)
Triceps Brachii
Triceps Brachii
Pronator Teres
O: Humeral head- medial
epicondylar ridge and common
flexor tendon
Ulnar head- coronoid process
of ulna
I: Middle of lateral surface of
radius
N: Median nerve
A: Pronates forearm, assists in
flexing forearm
Pronator Teres
Palmaris Longus
O: Medial epicondyle of humerus
I: Transverse carpal ligament and
palmar aponeurosis
N: Median nerve
A: Flexes wrist, assists in
pronation and flexion of
forearm
Palmaris Longus
Flexor Carpi Radialis
Origin Medial epicondyle of humerus
Insertion Base of 2nd metacarpal
Action Flexes and abducts hand (at
wrist)
Innervation Median nerve (C6 and C7)
(C6, C7)
Flexor Carpi Radialis
Flexor Carpi Ulnaris
O: medial epicondyle of humerus
olecranon and dorsal border of
ulna
I: Pisiform, hamate, 5th
metacarpal
N: Ulnar nerve
A: Flexes wrist and assists in
ADD, assists in flexing forearm
Flexor Carpi Ulnaris
Flexor Digitorum Superficialis
O: Humeral head- medial
epicondyle of humerus
Ulnar head- coronoid process
Radial head- oblique line of
radius
I: Palmar surface of middle
phalanx of medial 4 digits
N: Median nerve
A: Flex middle and proximal
phalanges of medial 4 digits,
aids wrist and forearm flexion
Flexor Digitorum Superficialis
Deep Layer of the Forearm
Flexor Pollicis Longus
O: Volar surface of radius,
interosseous membrane,
coronoid process of ulna
I: Base of distal phalanx of thumb
on palmar surface
N: median nerve
A: Flexes thumb
Flexor Pollicis Longus
Pronator Quadratus
O: Distal 4th volar surface of ulna
I: Distal 4th of lateral border on
volar surface of radius
N: median nerve
A: Pronates forearm
Pronator Quadratus
Extensor Carpi Radialis Longus
O: Lateral supracondylar ridge of
humerus
I: Dorsal surface of base of 2nd
metacarpal
N: Radial nerve
A: Wrist extension, ABD of hand
Extensor Carpi Radialis Longus
Extensor Carpi Radialis Brevis
O: Lateral epicondyle of
humerus, radial collateral
ligament
I: Dorsal surface of base of 3rd
metacarpal
N: Radial nerve
A: Wrist extension, ABD hand
Extensor Carpi Radialis Brevis
Extensor Digitorum
O: Lateral epicondyle of humerus
I: Lateral and dorsal surface of
phalanges of medial 4 digits
N: Radial nerve
A: Extends medial 4 digits,
assists in wrist extension
Extensor Digitorum
Extensor Digiti Minimi
O: Lateral epicondyle of humerus
I: Dorsum of proximal phalanx of
5th digit
N: Radial nerve
A: 5th digit extension
Extensor Carpi Ulnaris
O: Lateral epicondyle of humerus
I: Medial side of base of 5th
metacarpal
N: Radial nerve
A: Wrist extension, ADD hand
Extensor Carpi Ulnaris
Supinator
O: Lateral epicondyle of
humerus, lateral ligament of
elbow and annular ligament,
supinator crest and fossa of
ulna
I: Lateral and anterior surface of
radius
N: Radial nerve
A: Supinates forearm