Arm, Forearm, Wrist-Mod 3

Front 1

Describe the features of the distal humerus

Back 1

• Condyle (articulating surface)
– Capitulum • Articulates with the radius
– Trochlea • Articulates with ulna
• Two epicondyles (ms. attachment) – Medial & Lateral
• Three Fossae – Radial
– Coronoid – Olecranon

"CRTU"

Front 2

What are the differences between the radius and ulna?

Back 2

• Ulna longer proximally
• Radius longer distally
• Radius rotates around ulna
• Joined by interosseous membrane
• Both articulate with distal humerus

Front 3

What attaches at the radial tuberosity?
2. What articulates at the ulnar notch?

Back 3

1. biceps attach
2. site of articulation w/ ulna

Front 4

Describe the following joints
1) humeroulnar
2) humeroradial
3) proximal radioulnar
4) distal radioulnar

Back 4

• Humeroulnar *
– Hinge
– Flexion/extension
• Humeroradial *
– Modified Hinge
– Flexion/extension
– Supination/pronation
• Proxmial Radioulnar *
– Pivot
•
– Supination/pronation
Distal Radioulnar
– Pivot
– Supination/Pronation

Front 5

What happens to the olecranon process in extension and in flexion?

Back 5

In extension: olecronon process is in cose approximation to distal humerus in olecranon fossa

In flexion - olecranon process pulls away from distal humerus

Front 6

When does supination and pronation occur?

Back 6

• Supination occurs as the radial head spins on the capitulum
• Includes
– Humeroradial joint
– Proximal and distal radioulnar joints

Front 7

Supporting structures: Elbow region
1) Annular Ligament
2) Lateral Collateral Ligament
3) Medial collateral ligament

Back 7

1) •Encircles head of radius
•Holds the head of the radius against the ulna
•Protects against distal dislocation of the radius
2) •Protects against varus (medial) deviation of forearm
•Blends with annular ligament of radius
3) •Medial epicondyle of humerus to coronoid process and olecranon process
•Protects against valgus (lateral) deviation of forearm

Front 8

What are the 2 compartments of the muscles acting on the elbow

Back 8

anterior compartment: biceps brachii, brachialis (musculocutaneous nerve)
-used in flexion

posterior compartment
-triceps brachii, anconeus, brachioradialis
-radial nerve

Front 9

Describe the biceps brachii attachments, action, and innervation

Back 9

Attachments:
Short head
- coracoid process of the scapula
Long head
- supraglenoid tubercle
Both heads: radius via bicipital tendon
Action: flexes elbow (SH flex humerus)
supinates the forearm
Innervation: musculocutaneous n.

Front 10

What are the names of the biceps brachii based on?

Back 10

based on the lengths of the tendon, NOT the muscle.

Front 11

Brachilalis attachments, action, and innervation

Back 11

Attachments: - distal, anterior humerus
- coronoid process of the ulna + ulnar tuberosity
Action: flexes the elbow Innervation: musculocutaneous n.

Front 12

Triceps brachii attachments, action, and innervation

Back 12

Attachments:
Long head
- infraglenoid tubercle
Lateral head
- posterior sup. humerus
Medial head (deep)
- posterior inf. humerus All Heads: olecranon of the ulna
Action: Extend elbow (LH-ext, shoulder)
Long Head
Innervation: radial nerve

Front 13

Anoconeus attachments, action, and innervation

Back 13

Attachments: - lateral epicondyle of humerus
- olecranon of the ulna
Action: assists in extending the elbow Innervation: radial nerve

Front 14

Brachioradialis attachments, action, and innervation

Back 14

Attachments
-Lateral supracondylar ridge
- lateral distal radius
Action: Flexes elbow
Innervation:Radial nerve

Front 15

Muscles acting on radioulnar joints

Supinator (2) attachments, action, and innervation

Back 15

Attachments
- lateral epicondyle of humerus, supinator fossa, crest of ulna
- lateral, posterior and anterior surface of radius
Action Supinates forearm
Innervation Deep branch of radial nerve

Front 16

Biceps Brachii (another supinator)

Back 16

Attachments:
Short head
- coracoid process of the scapula
Long head
- supraglenoid tubercle
Both heads: radius via bicipital aponeurosis
Action: flexes elbow (SH flex humerus) supinates the forearm
Innervation: musculocutaneous n.

Front 17

Pronator teres attachments, action, and innervation

Back 17

Attachments
- Coronoid process and medial epicondlye
- Lateral surface of radius
Action Pronates and flexes forearm

Innervation: median nerve

Front 18

Pronator quadratus

Back 18

Attachments: distal, anterior ulna
-distal anterior radius

action: pronates forearm
Innervation: median nerve

Front 19

Describe the 2 rows of the carpal bones

Back 19

Proximal row apprximates with radius
Scaphoid, lunate, triquetrum, and pisiform

Distal row approximates with metacarpals
Hammate, capitate, trapezoid, trapezium (Med-Lat)

"So Long to Pinky, Here Comes the Thumb"
clockwise from thumb on volar surface

Front 20

Articulations of Wrist?

Back 20

1) Radiocarpal: between distal radius and proximal carpals
•condyloid type •wrist flexion/extension •wrist AB/AD

2) Midcarpal
between proximal and distal row of carpal bones
•plane synovial joint •gliding motions between carpals

Distal radioulnar joint: between distal end of radius and ulna
pivot synovial joint supination/pronation

Front 21

What's Colle's fracture?

Back 21

70% of these fractures occur in post- menopausal Women
Mechanism of injury is usually a fall on an outstretched arm
Dorsal Displacement of Distal Fragment

Front 22

What are the stabilizing ligaments?

Back 22

1. extensor retinaculum
2. flexor retinaculum- transverse carpal ligament

Front 23

What are the extensor muscles of the wrist?
What are the flexor muscles of the wrist?

Back 23

Extensors: extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris (radial)

Flexors: flexor carpi radialis (median), flexor carpi ulnaris

Front 24

ECRL attachments?
ECRB attachments/
ECU attachments/

Back 24

1) base of 2nd metacarpal
2) base of 3rd metacarpal
3) base of the 5th metacarpal

Also all attached to lateral epicondyle of humerus

Action: wrist extension
Innervation: radial nerve

Front 25

What is lateral epicondylitis?

Back 25

Repeated forceful flexion and extension of the wrist may strain the attachment of the common extensor tendon, producing inflammation of the periosteum of the lateral epicondyle (lateral epicondylitis).

Front 26

Attachments for the flexors, action,a dn innervation

Back 26

Attachments: medial epicondyle of humerus
FCR/FCU: base of metacarpals
PL: fascia of the palm

Action: wrist flexion
Innervation:
FCR - median
PL - median
FCU - ulnar

Front 27

What is the palmar fascia?

Back 27

Palmar fascia is a sheet of fibrous CT in the palm that helps stabilize and protect the structures of the palm.

Palmar fascia - aponeurosis

Front 28

Dupuytren's contracture?

Back 28

Dupuytren contracture is a benign, slowly progressive condition causing contracture of the palmar fascia. It has has no clear etiology or pathogenesis.

Front 29

Describe wrist abduction and adduction.

Back 29

Wrist ABduction (Radial Deviation) occurs as a result of contraction of both the ECRL and FCR
Wrist ADduction (Ulnar Deviation) occurs as a result of contraction of both the ECU and FCU

Front 30

Blood Supply

1) where does the axillary artery change names?

Back 30

1) at the inferior border of teres major, axillary artery changes to brachial artery
-brachial profunda artery is a major branch off the brachial artery

Front 31

At the level of the elbow, what does the brachial artery divide into?

Back 31

-radial artery
-ulnar artery: has anterior and posterior interosseous arteries

Front 32

1) superficial palmar arch
2) deep palmar arch

Back 32

1) ulnar artery continues into the hand and is the main supply to this
2) radial artery continues into hand and is main supply to this.

Front 33

1) what drains the superficial and deep venous palmar arches?
2) what happens as this network is prolonged proximally on the lateral side?
3) where does the basiclic vein arise?

Back 33

1) dorsal venous networks
2) prolonged as cephalic vein
3) basilic vein from medial side of dorsal venous networks

Front 34

1) axillary vein
2) median cubital vein

Back 34

he basilic and cephalic veins ultimately drain into the origin and termination of the axillary vein, respectively.
The median cubital vein is the communication between the basilic and the cephalic veins in the cubital fossa.

Front 35

What forms the triangular interval, and what passes through it?

Back 35

Borders: long and lateral heads of triceps and teres major.
Radial nerve and profunda brachii pass through it

Front 36

What is the triangular space bound by? What passes through it?

Back 36

Teres minor, teres major, and long head of triceps. Circumflex scapular artery passes through it

Front 37

What is the quandrangular space bordered by? What passes through it?

Back 37

Boundaries: teres minor, teres major, long head of triceps, and surgical neck of humerus

Axillary nerve and posterior humeral circumflex artery pass through it.