18 - MSK Shoulder to Hand Flashcards
which ligaments stablize the bones f the pectoral girdle
acromioclavicular ligament
coracoclavicular ligament
coracoacromial ligament
(names after the bones they bind together)
What would happen if ligrament was damaged
sprain
shoulder seperation
What is a shoulder dislocation
synovial joint no longer communicates
force
- hyperabducted
pectralis major draws humerus medially
Which nerves from the brachial plexus are at risk of injury in a shoulder dislocation
musculotaneous nerve (antibrachium)
axillary nerve (brachium)
what are the roattor cuff muscles
arise from the scapula to insert around the head of the humerus
stabalize the glenohumeral joint and contribute to circumduction of the shulder
SITS
- supraspinatus (initiate abduction) suprascapular nerve
- infraspinatus supracapular nerve
- teres minor axillary nerve
- subscapularis subscapular nerve
no muscles at the bottom
what are the muscles moving the radius and ulna
posterior extension
triceps brachii (3 tendons) radial nerve
anterior flexor musculocutaneous nerve
- brachialis
- biceps brachii
what does the bicipital aponeurosis do
aid in flexion of the forearm
attatched to ulna
What does the true tendon do
insert upon radial tuberoisity (bump on radius)
when put forearm in pronation, bump gets folded over
allows for supination of the forearm
What is the bicep muscle known as
screwdriver muscle
- flex elbow
- turning elbow
What does the brachial artery do
supplies the structures of the arm, forearm and hand
What are the two functions of the biceps brachii
What is it innervated by
true tendon: supination of forearm (radio-ulnar joint)
aponeurosis: flexion of forearm (elbow)
innervataed by musculocutaneous nerve
What does the tricep muscle do
What is it innervated by
extension of the forearm (elbow)
innervated by radial nerve
- radial groove runs through
What would a humeral fracture result in
peripheral nerve injuries
- axillary (proximal, high up)
- radial
- median (distally)
because of radial groove
Where do the superficial muscles of the anterior flexor compartment of the forearm arise from
arise from medial epicondyle
What are the anterior superficial muscles moving the forearm
pronator teres (pronation of forearm)
- attatched to radius
flexor carpi radialis (flexion of carpus)
palmaris longus
flexor carpi ulnaris (ulnar deviation when contracted)
innervated by the medial nerve
except for flexor carpi ulnaris (ulnar nerve)
Which muscles faciliate pronation of the forearm
pronator teres: superficial, proximal, strong
- median nerve
pronator quadratus: deep, distal, weak
- median nerve
position of radial tuberoistity follows
What muscles faciliate flexion of the carpus (wrist)
flexor carpi radialis: wrist flexion, radial deviation
- median nerve
flexor carpi ulnaris: wrist flexion, ulnar deviation
- ulnar nerve
independently these muscles cause radial or ulnar deviation of the wrist
What are the deep muscles moving the digits and thumbs of the anterior compartment
flexor digitorum superficialis (median nerve)
- sends tendon to intermediate phalanx
flexor digitrum produndus (ulnar nerve)
- sends tendons to distal phalanx
FDS –> capral –> FLDP –> finger tips
flexor pollicis (median nerve)
arise from interosseous membrane
What is the flexor digitorum produndus
flex distal interphalageal joint
- median and ulnar nerve
arises from the bones and interosseus membrane of the forearm
What is the flexor digitorum superficialis
flexion of proximal interphalangeal joint
- median nerve
Where do the superficial muscles of the posterior (extensor) compartment arise from
What innervates
lateral epicondyle of the humerus
radial nerve
What are the superficial muscles of the posterior compartments
extensor carpi radialis and ulnaris - extend the carpals
- circumduct the wrist
radialis: start as arm muscle fr radial deviation
ulnaris: extension of carpals
extensor digitorum - extend the digits
- extend the interphalangeal joints
- extend the MCP joints
- extend the radio-carpal joint
(crosses the interphalangeal joints, metacarpophalangeal joints and carpals)
Where do the deep muscles of the posterior (extensor) compartment arise from
What innervates
bones and interosseus membrane
radial nerve
What are the deep muscles of the posterior compartments
abductor pollicis - abducts the thumb
extensor pollicis - extends the thumb
come off radius
What is epicondylitis
What are the types
excessive forces that cause injury to the tendinous insertion sites
medial epicondyle: constantly extending the wrist, contracting flexi-carpal muscles to keep wrist straight
(golfers elbow)
lateral epicondylitis: extensor carpi muscles contracting
(tennis elbow)
What is cubital tunnel syndrome (funny bone)
compression of the ulnar nerve (c8-t1) in the cubital tunnel can lead to sensory and motor
- loss of sensation in the cutaneous distribution (palm and pink/ring finger) of the ulnar nerve (front and back of hand)
- weakinging of muscles of the hand and forearm having an action on the digits
What can happen after fall on out-stretched hand (FOOSH)
fracture in the distal radius (colle’s fracture)
radius absorbing most at fall because biggest at distal
(ulna big at proximal)
results in dinner fork deformity
What are the carpal bones
scaphoid - at base of thumb
capitate - in centre
- median nerve comes through)
pisiform and hamate - form the ulnar canal
- have ligament running through to create ulnar canal (ulnar nerve goes through and into palm muscles to innervate)
What is the carpal tunnel
where the digital flexor tendons and the median nerve enter the hand
- floor = carpal bones
- roof = transverse carpal ligament
What is the transverse carpal ligament
aka flexor retinaculum
roof of hand (palm side): keep all tendons down
What is the ulnar canal
form between pisiform and hamate (hook)
deep to pisi-hamate ligament
What would happen if there were a scaphoid fracture (FOOSH)
proximal segment of the scaphoid is prone to avascular necrosis
- death of bone
inflammed, funny colours –> death
“to the elbow we go”
pain in anatomical snuffbox
What is carpal tunnel syndrome
injury to median nerve through the carpal tunnel
- loss of sensation in the cutaneous distribution of the median nerve (thumb, 2, 3)
- muscles weakening of the intrinsic muscles of the thumb and hand (abduction and flexion of thumb)
Floor = carpal bones
Roof = transverse carpal ligament
due to inflammation of the digital flexor tendons (tendinitis)
recurrent branch: nerve takes uturn
What are clinicla tests to confirm carpal tunnel
tinel’s sign (pressing down on nerve)
tingle or pain down cutaneous distribution when
extreme flexion
(phalen’s test), more pressure on median nerve
