Arm and forearm Flashcards
4, 7, 11
6,912,3
Describe the articulations at the elbow
-Capitulum of humerus with radial head
-Trochlear of humerus with trochlear notch of ulna
-Olecranon of ulna with olecranon fossa of humerus
What muscles flex the elbow joint?
-Biceps
-Brachialis
-Brachioradialis
-Pronator teres
-Flexor carpi radialis
What structures run in spiral groove?
-Radial nerve
-Profunda brachii vessels
What is the clinical picture of a radial nerve injury at the spiral groove?
-Denervation of wrist extensors–> wrist drop
-Denervation of finger extensors–> finger drop
-Loss of sensation in first web space
What fracture is this?
Supracondylar fract
What injuries would be associated with supracondylar fracture?
-Brachial artery injury (loss of distal pulsation)
-AIN injury (unable to flex IPJ of thumb, DIPJ index and middle)
-Ulnar nerve injury (claw hand)
-Radial nerve injury (wrist drop, finger drop)
What is the origin/insertion/action/innervation of coracobrachialis?
Origin: Coracoid process
Insertion: mid humerus, medial
Action: flexion, adduction
Innervation: musculocutaneous nerve
Biceps brachii origin/insertion/action/innervation. What are the relations to the biceps tendon?
Origin
–> Coracoid process (short head)
–> supraglenoid tubercle (long head)
Insertion:
–> radial tuberosity
Action
–> flexion, supination
Innervation:
–> musculocutaneous nerve
Relations to biceps tendon:
–> Medial: median nerve and brachial artery
–> lateral: radial nerve
Brachialis origin, insertion, action, innervation
O: Anterior humerus
I: Ulnar tuberosity (anterior)
Action: flexing forearm
Innervation: musculocutaneous
Triceps origin, insertion, action, innervation. What lies between medial and lateral heads?
O:
–> infraglenoid (long head)
–>Posterior humerus (lateral head)
–> Posterior humerus (medial head)
I: olecranon
Action
-extension of elbow
-long head can adduct humerus and extend it from flexed position
Innervation:
-radial nerve
-Radial nerve and profunda brachii muscle lie between medial and lateral heads
What is the origin/insertion/action and innervation of pronator teres
Origin:
–> medial epicondyle humerus and coronoid process of ulna
Insertion
–> Mid-lateral radius
Action
–> pronation, flexing forearm
Innervation:
–> median nerve
Origin/insertion/action/innervation of flexor carpi radialis
O:
–> Medial epicondyle
I:
–> 2nd + 3rd MC bases
Action
–> flexes wrist
Innervation:
–> median nerve
Palmaris longus
O:Medial epicondyle
I:
–> palmar aponeurosis
Action:
–> Flexing wrist
Innervation:
–> Median nerve
Flexor carpi ulnaris:
O:
–> medial epicondyle and posterior ulna
I:
–> pisiform, base of 5th metacarpal
Action
–> flexing wrist
Innervation:
–> ulnar nerve
FDS origin, insertion, action, innervation
O:
–> Medial epicondyle, proximal anterior ulnar, anterior radius
I:
–> Base of middle phalanges
Action:
–> Flexion PIPJ
Innervation:
–> Median nerve
What is the common flexor origin?
-Medial epicondyle
-Where superficial flexors of forearm originate (pronator teres, FCRL, Palmaris longus, FDS, FCU)
What is the innervation of the superficial flexors of the forearm?
Median nerve except flexor carpi ulnaris
What are the superficial flexors of forearm?
-Pronator teres
-FCRL
-Palmaris longus
-FDS
-Flexor carpi ulnaris
What are the deep flexors of the forearm?
-FDP, FPL, pronator quadratus
What is the innervation of the deep flexor muscles of the forearm?
Median –> anterior interosseous nerve except ulnar half FDP
What is the origin/insertion/action of FDP?
Origin:
–> anterior and medial ulna
Insertion
–> base of distal phalanx
Action:
–> Flexing DIPJ
Innervation;
-radial half median
-ulnar half ulnar
What is the origin/insertion/action of FPL
O:
-Anterior and lateral radius
I:
-Base of distal phalanges
Action:
–> flexing IPJ thumb
What is the origin/insertion/action of pronator quadratus?
O: Distal ulna
I: volar radius
Action: pronating hand
What are the superficial extensors of the forearm?
-Brachioradialis
-ECRL
-ECRB
-Anconeus
-Extensor digitorum
-Extensor digiti minimi
-Extensor carpi ulnaris
What is the origin/insertion/action/innervation of brachioradialis?
O: lateral supracondylar humerus
I: lateral distal radius
Action: flexing forearm
Innervation: radial nerve
What is the origin/insertion/action/innervation of ECRL?
O: lateral supracondylar humerus
I: second metacarpal base
Action: extending wrist
Innervation: radial nerve
What is the origin/insertion/action/innervation of ECRB?
O: Lateral epicondyle of humerus
I: third metacarpal base
Action: extending wrist
Innervation: radial nerve
What is the origin/insertion/action/innervation of Anconeus?
O: lateral epicondyle of humerus
I: third metacarpal base
Action: extending wrist
Innervation: radial nerve
What is the origin/insertion/action/innervation of Extensor digitorum?
O: lateral epicondyle of humerus
I: extensor aponeurosis
Action: extending digits
Innervation: radial –> PIN
What is the origin/insertion/action/innervation of Extensor digiti minimi?
O: common extensor tendon
I: small finger extensor expansion over P1
Action: extending small finger
Innervation: Radial–> PIN
What is the origin/insertion/action/innervation of extensor carpi ulnaris?
O: lateral epicondyle of humerus
I: 5th metacarpal base
Action: extending/adducting hand
Innervation: radial –> PIN
What are the deep extensors of the forearm?
Supinator
Anductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
Extensor indicis proprius
What is the origin/insertion/action/innervation of supinator?
O: lateral epicondyle of humerus, ulna
I: dorsolateral radius
Action
-Supinates forearm
What is the innervation of the deep extensors of the forearm?
Posterior interosseous nerve
What muscles does the posterior interosseous nerve innervate?
-Extensor digitorum
-Extensor digiti minimi
-Extensor carpi ulnaris
-Deep extensors of forearm
What is the origin/insertion/action/innervation of Abductor pollicis longus?
O: dorsal ulna/radius
I: first metacarpal base
Action: abducting/extending thumb
What is the origin/insertion/action/innervation of Extensor pollicis brevis
O: dorsal radius
I: thumb proximal phalanx base
Action: extending thumb MCPJ
Extensor pollicis longus
O: dorsolateral unla
I: thumb dorsal phalanx base
Action: extending thumb IPJ
What is the origin/insertion/action/innervation of extensor indicis proprius
O: dorsolateral ulna
I: index finger extensor apparatus (ulnar aspect)
Action: extending index finger
What are the boundaries of the cubital fossa?
-Superolateral: brachioradialis muscle
-Medially: pronator teres
-Floor: brachialis
What is the contents of the cubital fossa?
Lateral to medial:
-radial nerve
-Biceps tendon
-Brachial artery
-Median nerve
