MSK Upper Limb 2 Flashcards
Label the superficial & intetermidiate muscles of the anterior forearm
Where do the superficial forarm flexors attach
Medial epicondyl of the ulnar via the common flexor tendon
State the order of the superficial forearm flexors of the forearm from medial to lateral
What is the action of pronator teres?
Pronation of forearm
Apart from flexing the wrist, which superficial muscle is involved in abduction (radial deviation) of the wrist joint
Flexor carpi radialis
Apart from flexing the wrist, which superficial muscle is involved in adduction (ulnar deviation) of the wrist joint
Flexor carpi ulnaris
What nerve supplies the superficial muscles of the anterior compartment of the forearm
Median Nerve:
Flexor Carpi Radialis
Flexor Digitorum superficialis
Pronator Teres
Ulnar Nerve:
Flexor Carpi Ulnaris
Where is the flexor digitum located
Lies immediately deep to the superficial group of flexors in the forearm and is seen as the only muscle on the intermediate group of the forearm
Origin
Insertion of FDS
Action
Origin:
Humeroulnar head: Medial epicondyle of humerus, coronoid process of ulna
Radial head: Proximal half of anterior border of radius
Insertion:
All fingers except thumb at the middle phalanx
Action:
Metacarpophalangeal and proximal interphalangeal joints 2-5: Finger flexion
State the bone names of the hand
Name the carpel bones
What is special about the brachioradialis
Only muscle in the anterior forearm which is not a flexor
Label the Deep Group of Muscles in the anterior compartment of the forearm
Flexor Digitorum Profundus
Action:
Innervation:
Action:
Flexion of hand and both intephalangeal joints
Innervation:
Medial side (Ring and pinky) :
Ulnar Nerve
Lateral side:
Median Nerve
Flexor Pollicis Longus (FPL) Innervation
Action
Innervation
Action:
Flexes thumb
Innervation
Median Nerve
Pronator Quadratus
Action
Innervation
Action:
Pronator at both the proximal and distal radioulnar joints.
Innervation:
Median Nerve
Fill in the blanks:
The median nerve enters the forearm to the brachial artery.
It then heads under the muscle and passes down the forearm between the FDS and FDP.
It enters the carpal tunnel the flexor retinaculum.
The median nerve enters the forearm medial to the brachial artery. It then heads under the pronator teres muscle and passes down the forearm between the FDS and FDP.
It enters the carpal tunnel under the flexor retinaculum
Which muscle(s) does the median nerve not supply in the anterior forearm?
Flexor carpi ulnaris and medial half of flexor digitorum profundus
Fill in the blanks:
After passing posterior to the of the humerus the ulnar nerve enters the forearm by passing between the heads of
Both the ulnar nerve and ulnar artery descend close to each other down the medial aspect of the forearm
The ulnar nerve lies to the ulnar artery at the level of the wrist
After passing posterior to the medial epicondyle of the humerus the ulnar nerve enters the forearm by passing between the heads of flexor carpi ulnaris muscle. Both the ulnar nerve and ulnar artery descend close to each other down the medial aspect of the forearm
The ulnar nerve lies medial to the ulnar artery at the level of the wrist
What two muscles anchor the fibrous flexor reticulum?
The scaphoid and the trapezium on the lateral side
The pisiform and hamate bone on the medial side.
Contents of Carpal Tunnel
4 tendons of flexor digitorum superficialis
4 tendons of flexor digitorum profundus
1 tendon of pollicis longus
median Nerve
State the 5 compartments of the hand
1) Thenar compartment
2) Hypothenar compartment
3) Lumbricals and long flexor tendons – central compartment
4) Adductor compartment
5) Interosseous compartmen
State the thenar muscles
· Abductor pollicis brevis (APB)
· Flexor pollicis brevis (FPB)
· Opponens pollicis (OP)
Nerve supply of thennar compartment
Median Nerve (C8, T1)
Except the deep belly of FPB- ulnar
State the Hypothenar Muscles
· Abductor digiti minimi
· Flexor digiti minimi
· Opponens digiti minimi
Nerve supply of hypothenar
Ulnar Nerve (C8-T1)
Muscles of the central compartment
Innervation
- flexor digitorum profundus
- flexor digitorum superficialis
- Flexor pollicis longus
- Lumbricals (4 which originate in the hand)
Functions of Lumbricals
Flex the fingers at the metacarpophalangeal joints
extend the interphalangeal joint of 2nd to 5th digits.
Innervation of lumbricals
The medial two lumbricals are innervated by ulnar nerve and the lateral two are innervated by median nerve.
Abductor Pollicus
Origin
Insertion
Action
Origin:
- *Transverse head:** Palmar base of metacarpal bone 3
- *Oblique head:** Capitate bone, palmar bases of metacarpal bones 2 & 3
Insertion:
Medial base of proximal phalanx 1 (via ulnar sesamoid bone)
Action:
Adducts the thumb
How many interossei muscles are there and whats their innervation and action
4 dorsal
3 Plantar
Innervation:
Ulnar Nerve (T1)
Action:
Dorsal- abduct
Palmar- adduct
DAB and PAD
Which artery is the main contributor of the deep palmar arch
Radial
Which artery is the main contributor of superficial palmar arch?
Ulnar Artery
Label
What sits between the ulna and the carpal bones?
Articular disk (condyloid joint)
Which carpel bone does the radius articulate with
scaphoid and lunate
What type of fluid is found between the forearm and carpal bones?
synovial
Flexion of the wrist joint is caused by contraction of the muscles in the ……….
Anterior compartment
Extension of the wrist joint is caused by contraction of the muscles in the ……..
Posterior compartment
The combined action of flexor and extensor carpi ulnaris cause ………..or ……….. of the wrist
The combined action of flexor and extensor carpi ulnaris cause ulnar deviation or adduction of the wrist
Which muscles are responsible for radial deviation or abduction of the wrist
flexor and extensor carpi radialis
Circumduction of the joint is the rotation of the wrist using a combination of what
Flexor and extensor carpi radialis and ulnaris
Name the bones in the hand (all of them) as well as the joints of the fingers
Groups of the muscles of the posterior forearm
1) Muscles that extend and abduct or adduct the hand at the wrist joint
2) Muscles that extend the medial four digits
3) Muscles that extend or abduct the thumb
Label
What are the muscles that extend and abduct or adduct the hand at the wrist joint
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
What is the action of extensor carpi radialis longus and brevis on the wrist joint?
They both extend and abduct the wrist joint.
What other action are they involved with the help of flexor carpi radialis?
They cause radial deviation of the wrist
What are the muscles that extend the medial four digits
Extensor digitorum
Extensor indicis
Extensor digiti minimi
Label
What are the muscles that extend or abduct the thumb
Abductor pollicis longus (APL)
Extensor pollicis brevis (EPB)
Extensor pollicis longus (EPL)
Summerise the innervation and action for these muscles
Name the 2 branches of the radial nerve as it leaves the cubital fossa
Deep branch (aka posterior interosseus nerve)
Superficial branch (purely sensory)
Label these branches of the radial nerve
What is this
Extensor retinaculum
Borders of the anatomical snuff box
Medial border (1 tendon)
Extensor pollicis longus tendon
Lateral Border (2 tendons)
Tendons of extensor pollicis brevis and abductor pollicis longus
Floor (2 carpal bones)
scaphoid and trapezium
Which artery can you feel pulsating on its floor?
Radial artery
Innervation and action
Extensor pollicis longus
Extensor pollicis brevis
Abductor pollicis longu
Extensor pollicis longus - Extends wrist and distal phalanx of thumb
Extensor pollicis brevis - Extends wrist and proximal phalanx of thumb
Abductor pollicis longus - Extend wrist and abduct thumb
All Innervated by posterior intersosseus nerve (radial nerve)
Which muscles attach onto the extensor expansion?
- lumbricals
- extensor digitorum brevis
- dorsal interosseous
- Palmar interosseous
