Upper limb injuries Flashcards
what is thoracic outlet syndrome? What 2 things can cause it? AXILLA
- compression of nerves and vessels in the apex of the axilla
- trauma
- repetition in arm lifting
what does thoracic outlet syndrome present with? AXILLA
- pain in affected limb (depending on severity and no. of nerves damaged)
- tingling
- muscle weakness and discolouration
what can be biopsied to test for breast cancer and why? AXILLA
- axillary lymph nodes
- most of lymph from breast tissue drains here
what is the name for the removal of axillary lymph nodes? What can this lead to the damage of and what does this cause as a consequence? AXILLA
- axillary clearance
- damamge to long thoracic nerve which will cause a winged scapula as serratus anterior is innervated by this nerve (holds scapula against ribcage)
what vein connects the basillic and cephalic vein and what is it commonly used for? CUBITAL FOSSA
- median cubital vein
- venepuncture
how is a suprachondylar fracture caused? CUBITAL FOSSA
-falling on a flexed elbow
fractures affecting blood flow into the forearm from the brachial artery causes what (specific name)? explain. CUBITAL FOSSA
- volkmanns ischaemic contractures
- ischaemia resulting in flexors of forearm becoming fibrotic and short=uncontrolled flexion of wrist
what is carpel tunnel syndrome and what can it cause if left untreated? CARPAL TUNNEL
- compression of median nerve due to thickened ligaments and tendon sheath
- cause atrophy and weakness of thenar muscles
what 2 physcial examinations can be done to test for carpal tunnel syndrome? CARPAL TUNNEL
- lightly touch wrist to detect pain
- flex wrist for 60 secs to detect pain
Tenderness in the anatomical snuffbox is caused by what? How does this most commonly occur? ANATOMICAL SNUFFBOX
- fracture of the scaphoid
- falling on an outstretched hand
Why can scaphoid fractures be an emergency? ANATOMICAL SNUFFBOX
- arterial supply is distal to proximal
- fracture towards proximal end of scaphoid can cause avascuar necrosis of the bone tissue=arthritis
What causes a winged scapula? SCAPULA
- damage to long thoracic nerve
- loss of innervation to serratus anterior
- can no longer hold scapula against ribcage
Give 3 ways of damaging the long thoracic nerve
- trauma to shoulder
- repetitive movements involving shoulder
- inflammation of structures around the nerve
How can you test for a winged scapula
push against a wall
what is the most common point of fracture on the clavicle? CLAVICLE
junction of medial 2/3 to lateral 1/3
What movement occurs to lateral 1/3 of clavicle when fractured and why?
- inferior and medial
- inferior due to weight of upper limb
- medial due to pec major
What movement occurs to medial 2/3 of clavicle when fractured and why?
-superiorly due to sternocleidomastoid
Upwards movement of medial 2/3 of clavicle can result in what position and why?
- waiters tip position (erbs palsy)
- damage to suprascapula nerve which supplies supra and infraspinatus which are lateral rotators
- results in unopposed medial rotation of upper limb
Why can a mid shaft fracture of the humerus cause wrist drop? HUMERUS
- damage to radial nerve which is tightly adhered to the radial groove
- innervates wrist extensors in forearm and so unopposed flexion occurs
what type of humerus fracture can cause ischaemic volkamnns contracture?
- distal humerus
- e.g. supracondylar, medial epicondyle, supraepicondylar fracture
what nerve in particular can be damaged by a medial epicondyle fracture and what happens as a result?
- ulnar nerve
- ulna claw and loss of sensation to medial 1 and a half fingers (dorsal and ventral)
name the 2 fractures associated with the radius and ulna and state what happens in each case.
DISTAL fracture
- colle’s fracture (distal part goes posteriorly)
- smiths fracture (distal part goes anteriorly)
what is a boxers fracture? METACARPALS
- 5th metacarpel (little finger)
- punching
- neck fracture-distal part displaces posteriorly
what is a bennets fracture? METACARPALS
- 1st metacarpal base fracture
- caused by hyperabduction of thumb
what is the common cause of accessory nerve damage?
-iatrogenic-medical procedures
how can you test for accessory nerve damage?
- trapezius test
- shrug shoulders
what nerves and roots are affected in ERBs palsy? BRACHIAL PLEXUS
C5 and 6
-musculocutaneous, axillary, nerve to subclavius, suprascapular
what muscles are affected in ERBs palsy?
- M=all bicep muscles (BBC)
- A=deltoid and teres minor
- N to S=subclavius
- S=supraspinatus and infraspinatus
What motor functions are compromised in ERBs palsy?
- supinationof forearm, flexion of shoulder
- abduction of shoulder and lateral rotation
what sensory functions are lost in ERBs palsy?
lateral side of arm (axillary and musculocutaneous innervations)
Give 2 ways ERBs palsy can occur and explain what happens to the angle between the shoulder and neck.
- trauma (e.g. falling off motorbike)
- shoulder dystocia (difficult birth)
- angle increases
what is the name of the position that forms during Erbs palsy?
waiters tip
what causes klumpkes palsy? Give 2 examples
- being pulled from the arm at birth
- catching a branch above when falling from a tree
what brachial plexus roots are affected in klumpkes palsy?
C8 and T1
Mainly what nerve is affected in klumpkes palsy?
ulna nerve
what muscles are affected in klumpkes palsy and what is the presenting feature?
- intrinsic muscles of the hand
- some of forearm
- claw like hand
describe the motor and sensory implications of axillary nerve damage
motor-no abduction due to lack of innervation to deltoid and teres minor
sensory-loss of sensation over regimental badge area
With long standing axillary nerve damage, what can be palpated due to deltoid atrophy?
greater tuberosity of humerus
How can the musculocutaneous nerve be injured?
stab wound to axilla region
what motor functions are affected with a musculocutaneous nerve injury?
flexion at shoulder and elbow is weakened as well as supination
Radial nerve damage in the axilla-motor and sensory loss?
yes
Radial nerve damage in the radial groove. Does it fully damage triceps brachii? What happens in sensory innervation?
- no, only partially
- only superficial branch out of 4 cutaneous nerves affected as other branches already arisen. Loss of hand innervation
Name 2 other injuries of radial nerve besides axilla and radial groove injuries.
- deep branch (motor)
- superficial branch (sensory)
In superficial and deep branch of radial nerve injuries, how do they occur and what happens?
-superficial=laceration or stabbing
-deep=radial head fracture
Sensory-hand innervation lost
Motor-post forearm muscles affected, however ECRL is strong extensor and isnt affected so WRIST DROP does NOT occur
what is the most common area of fracture at the elbow, in an ulna nerve damage?
-medial epicondyle
at the elbow, damage to the ulnar nerve results in what sensory and motor loss?
sensory-all lost
motor-abduction occurs (due to inability to adduct using FCU), no abd or adduction of fingers (interossei), lack of movement of little and ring finger (lumbricals)
In ulnar nerve damage at the wrist, what is the difference between sensory loss here and sensory loss when damaged at the elbow.
at the wrist, the dorsal branch isnt affected and so the dorsal one and a half medial fingers as well as their associated palmar areas are not affected
what are the presenting features of the ulna claw after damage at the WRIST? why does this occur?
Applying to medial 2 fingers (little and ring)
-unopposed hyperextension of MCP joint and flexion of IP joint due to loss of lumbrical function-hyperextension because only the extensors in post forearm are acting and flexion at IP due to ant forearm muscles working
Explain the ulnar paradox
- expect hand to look more deformed but in actual fact, looks more normal
- damage at the elbow
- flexor digit profundus affected here and so flexion at distal IP joint doesnt occur-only proximal IP joint flexion occurs
What is the presenting feature in median nerve damage at the elbow?
when ASKED to make a fist, patient can only flex little and ring finger
- lateral 2 fingers cannot flex at the MCP joint due to loss of lumbrical function
- cannot flex at the IP joints due to loss of function of ant forearm muscles
what is acromioclavicular joint dislocation also known as?
separated shoulder
what can be caused from fracture of the scaphoid? where does the tenderness arise? what will the fracture increase likelihood of?
avascular necrosis
anatomical snuffbox
arthritis
what carpal bone dislocates when falling on a dorsiflexed (extended) wrist? what syndrome occurs as a result?
- lunate
- moves anteriorly and compresses contents of carpal tunnel=carpal tunnel syndrome
what 3 things occur as a result of the lunate bone dislocation?
- avascular necrosis
- parasthesia (pins and needles) of sensory distribution in median nerve area
- weakness of thenar muscles
