Cortex- General Trauma Flashcards
what fractures are associated with substantial blood loss
pelvis and femur
what is primary bone healing
occurs when there is a minimal fracture gap and the bone simply bridges the gap with new bone formed from osteoblasts (hairline fractures + fixed fractures)
what is secondary bone healing
when there is a gap at fracture site
involves an inflammatory process and the recruitment of pluropotential stem cells which differentiate into different cells during the healing process
what are the stages of secondary bone healing
Fracture occurs
Haematoma occurs with inflammation from damaged tissues
Macrophages and osteoclasts remove debris and resorb the bone ends
Granulation tissue forms from fibroblasts and new blood vessels
Chondroblasts form cartilage (soft callus)
Osteoblasts lay down bone matrix (collagen type 1)– Enchondral ossification
Calcium mineralisation produces immature woven bone (hard callus)
Remodelling occurs with organization along lines of stress into lamellar bone
how long do the soft and hard callus take to form
soft= 2nd to 3rd week
hard= 6-12 weeks
what does secondary bone healing require
blood supply, nutrients, stem cells, a little movement (compression or tension)
what might cause atrophic fracture non union
lack of blood supply, no movement, too big a gap (rigid fixation with a fracture gap), soft tissue trapped in gap (interposition)
what might impair fracture healing
smoking (vasospasm), vascular disease, chronic ill health, malnutrition, no movement
what causes hypertrophic non unions
excessive movement at the fracture sight with abundant hard callous formation
what is and causes a transverse fracture
how can it present
occur with pure bending force where the cortex on one side fails in compression and the other in tension
may not shorten (unless completely displaced) but may angulate or result in rotational malalignment
what causes oblique fractures, how can they be fixed, how can they present
occur with a shearing force (fall from height, deceleration)
can be fixed with interfragmentary screw
tend to shorten and may angulate
what causes spiral fractures, how can they be fixed, how can they present
torsional forces
interfragmentary screws
most unstable to rotational forces, may angulate
what causes comminuted fractures,
what are they,
how can they be fixed,
how can they present
high energy/ poor bone quality
fractures with three or more fragments
tend to be stabilised surgically
may be soft tissue swelling and periosteal damage with reduced blood supply to the site (impaired healing). very unstable
what are segmental fractures and how are they fixed
when bone is fractured in two different places
very unstable require stabilisation with long rods or plates
how can a fracture of a long bone be described
according to site: proximal, middle or epiphyseal
according to type of bone involved: diaphyseal (shaft), metaphyseal or epiphyseal
how can fractures at the end on a lone bone (metaphyseal/ epiphyseal) be described
can be intra (extending into the joint)/ extra articular
what do intra articular fractures have a greater risk of
stiffness, pain, post traumatic OA,
what does fracture displacement depend on
degree of translocation, angulation and rotation
what are the directions of translation of a fracture
distal fragment can go anteriorly or posteriorly displaced
or
medially or laterally translated
what words describe displacement in the forearm and hand
volar (or palmar) and dorsal
ulnar and radial
what is an off ended fracture
one where end is 100% (% of width of bone) displaced
what is angulation
the direction which the fragments point towards and the degree of deformity
how can angulation be described- generally and in upper and lower limbs
medial or lateral and anterior or posterior
upper limb- radial, ulnar, dorsal, volar
lower limb- varus (distal fragment pointing towards midline) and valgus (distal away from the midline)
how is angulation measured
in degrees from the longitudinal axis of the diaphysis of a long bone
what does angulation tell you
direction of forces of injury
reversed direction of forces required to reduce a fracture
what can residual displacement/angulation lead to
deformity, loss of function, abnormal pressure on joints (post traumatic OA)
why is the rotation of the distal fragment inportant
as rotational malalignment is poorly tolerated and needs to be corrected when managing fractures
what are the clinical signs of a fracture
localised bony tenderness- not diffuse mild tenderness
swelling
deformity
crepitus (bone ends grating)
what is a useful rule to determine if a patient needs an x ray to exclude a fracture
if they can weight bear
what should the assessment of an injured limb include
open or closed?
distal neurovascular status (pulses, cap refill, temp, colour, sensation, motor power)
compartment syndrome?
status of the skin and soft tissue envelope
what usually views are done in x rays for fractures
AP and lateral (two views always required)
when are oblique views helpful
complex views: scaphoid, acetabulum, tibial plateau
what is a tomogram
moving x ray to take images of complex bones- mandibular fractures
when is CT used in fractures
asses fractures of complex bones (vertebrae, pelvis, calcaneus, scapular glenoid)
can help to determine the degree of articular damage and help surgical planning for complex intra-articular fractures (tibial plateau, distal tibia)
when is an MRI used for fractures
to detect occult (hidden) fractures when suspected but not on x ray (hip scaphoid)
when are technetium, bone scans used in fractures
to detect stress fractures (hip, femur, tibia, fibula, 2nd metatarsal) as these may fail to show up until hard callus begins to appear
what is the initial management for a long bone fracture
clinical assessment, analgesia (usually IV morphine), splintage/ immobilisation, investigation (usually X rays)
what might splintage or immobilisation involve
the application of a temporary plaster slab (backslab), sling, orthosis, thomas splint (femoral shaft fractures
when should reduction of a fracture be done before x rays
if there is obvious fracture dislocation or if there is risk of skin damage from excessive pressure
how are undisplaced, minimally displaced and minimally angulated fractures which are considered stable treated
non operatively with a period of splintage or immobilisation and then rehab
what do displaced or angulated fractures need
reduction under anaesthetic
closed reduction and cast application may be performed with serial x rays to ensure no loss of position
how are unstable injuries be treated
with surgical stabilisation
how are unstable extra articular diaphyseal fractures treated
open reduction and internal rotation (ORIF)
or external fixation (but pin site infection and loosening)
when should ORIF be avoided
where the soft tissues are too swollen or blood supply is tenuous, where ORIF might cause extensive blood loss or is plate fixation may be prominent
in this case- closed reduction and indirect internal fixation with intramedullary nail
what do displaced intra articular fractures need
anatomical reduction and rigid fixation by way of ORIF
if involving joint mat need joint replacement or arthrodesis
eldery patients with co morbidities, osteoporosis and dementia are at higher risk of what?
complications of surgery, failure of fixation, failure to rehabilitate
why are older patients more likely to be treated non surgically
as lower functional demand usually
what are the early local complications of fractures
compartment syndrome, vascular injury with ischaemia, nerve compression/ injury, skin necrosis
what are the early systemic complications of fractures
hypovolaemia, fat embolism, shock, acute respiratory distress syndrome, acute renal failure, systemic inflammatory response syndrome (SIRS), multi organ dysfunction syndrome, death
what are the late local complications of fractures
stiffness, loss of function, chronic regional pain syndrome, infection, non union, mal union, volkmann’s ischaemic contracture, post traumatic osteoarthritis, DVT
what are the main late systemic complications of a fracture
PE- several days to weeks after fraction
what causes the pressure to rise in compartment syndrome
bleeding and inflammatory exudate from fracture and injury
what does the rise in pressure in compartment syndrome cause
can compress the venous system causing congestion within the muscle and secondary ischaemia as arterial blood cannot supply the congested muscle
how does muscle ischaemia manifest
severe pain
compression of nerves can cause paraesthesiae and sensory loss
what are the cardinal clinical signs of compartment syndrome
increase pain on passive stretching of the involved muscle
severe pain outwith the anticipated severity in the clinical contex
what are the physical signs of compartment syndrome
limb will be tensely swollen and the muscle is tender to touch
loss of pulses- end stage ischaemia (diagnosis has been made too late)
what must be done when a diagnosis of compartment syndrome has been made
removal of any tight bandages
emergency fasciotomies
(open wound left for a few days)
secondary closure
what happens if compartment syndrome is left untreated
ischaemic muscle will necrose= fibrotic contracture a.k.a. volkmann’s ischaemic contracture and poor function
name the nerve injury commonly affected by a colles fracture
acute median nerve compression/ carpal tunnel syndrome
name the nerve injury commonly affected by an anterior shoulder dislocation
axillary nerve palsy
name the nerve injury commonly affected by a humeral shaft fracture
radial nerve palsy (in spiral groove)
name the nerve injury commonly affected by a supracondylar fracture of the elbow
median nerve injury
name the nerve injury commonly affected by a posterior dislocation of the hip
sciatic nerve injury
name the nerve injury commonly affected by a ‘bumper’ injury to lateral knee
common peroneal nerve palsy
how can vessels be damaged
stretches, compressed, torn or transected
when can vascular damage cause arterial occulusion
partial tears affected the arterial intima can thrombose
what injuries have a higher risk of vascular injuries
penetrating injuries knee dislocation (popliteal artery) paediatric supracondylar fracture of the elbow (brachial artery) shoulder trauma (axillary artery) pelvic fractures
what are signs of reduced distal circulation
reduced/ absent pulses, pallor, delayed cap refill, cold to touch
what what can help distinguish location of a arterial occulsion
urgent angiography in theatre
how can temporary restoration of circulation be achieved
shunt or vascular repair with bypass graft or endoluminal stent
how can haemorrhage from arterial injury in the pelvis be controlled
angiographic embolisation performed by interventional radiologists
why might skin breakdown after a fracture
if there is a protruding spike/ tension on the skin it can cause devitalisation and necrosis
what needs to be done when there is tenting of the skin seen with ‘blanching’ - why
fracture should be reduced as an emergency (under analgesia +/- sedation)
to avoid subsequent necrosis
what is de gloving and what can it cause
when a shearing force caused avulsion of the skin from the underlying blood vessels
can result in skin ishaemia and necrosis
underlying haematoma may also increase pressure on the skin occluding the capillaries
what are the signs of de gloving
will not blanch on pressure and may be insensate
what is a fracture blister
when inflammatory exudates cause lifting of the epidermis of the skin
what are the signs of fracture healing
resolution of pain and function
absence of point tenderness
no local oedema
resolution of movement at fracture site
what are the signs of non union
ongoing pain
ongoing oedema
movement at fracture site
bridging callus may be seen on x ray
which bones heal slowly
tibia (16 weeks- over a year)
femoral shaft (3-4 months)
cortical fractures heal slower than metaphyseal fractures
what is delayed union
when a fracture has not heal in the expected time
how can infection influence delayed union
infection can cause delayed union
if diagnosed can be suppressed with antibiotics and healing can occur
if not treated can cause infected non union
what type of non union can infection cause
infected, atrophic, hypertrophic
what fractures are prone to poor healing due to poor blood supply
scaphoid, distal clavicle, subtrochanteric of the femur, jones fracture of the fifth metatarsal
why might intraarticular fractures not heal (hip, scaphoid)
synovial fluid inhibits healing of fracture gap
when do DVTs occur after fractures
pelvic or lower limb fractures with a period of instability
what prophylaxis should be given for DVTs
LMWH
is suspected do duplex scanning and anticoagulation
what is fracture disease
stiffness and weakness due to the fracture and subsequent splintage in cast
how is fracture disease treated
most resolve, may be helped with physio
what fractures are prone to developing AVN
femoral neck, scaphoid, talus
what is the treatment of symptomatic cases of AVN
surgical management- THR, arthrodesis
what can cause post traumatic OA
intraarticular fracture, ligamentous instability, fracture malunion
what is complex regional pain and syndrome
chronic pain response to injury- constant burning or throbbing, sensitivity to stimuli (allodynia), chronic swelling, stiffness, painful movement, skin colour changes
what can cause CRPS
idiopathic (type 1)
peripheral nerve injury (type 2)
what is the management for CRPS
analgesics, anti depressants (amitriptyline), anticonvulsants (gabapentin), steroids might help
tens machine, physio, lidocaine patches, nerve blocking injections
can fractures will an infection lasting more than 2-3 weeks still heal
yes if suppressed by metal work will need to be removed
what are the two causes open fractures
inside out- bone punctures skin
outside in- laceration of the skin from tearing or penetrating injury
what is the main priority in treating open fractures
avoiding infection
what do infection of long bone after open fractures often require
extensive removal of bone with shortening- surgery to lengthen
sometimes amputation
what does gustiol classification do
describes the degree of contamination, the size of the wound- whether it can be closed or requires plastic surgery cover, and the presence of an associated vascular injury
what does initial management of an open fracture include
IV broad spectrum antibiotics (flucloxacillin- gram pos, gentamicin- gram neg, metronidazole- anaerobes if soil contamination)
application of sterile/ antiseptic soaked dressing
fairly prompt surgery
what does surgical management of an open fracture involve
removal of all contaminated or non viable soft tissue (debridement)
internal or external fixation
how can haematoma spread infection
acts as culture medium
what can wound tension result in
skin necrosis and wound breakdown
how can wounds that cannot be primarily closed be treated
skin graft, local flap coverage
what tissues readily accept a skin graft
muscle, fascia, granulation tissue, paratendon, periosteum
what does a delayed reduction increase the risk of
requiring an open reduction
recurrent instability
what conditions can cause hypermobility
ehlers danlos and marfans
what injuries can be associated with dislocations
tendon tears
nerve injuries
vascular injuries
compartment syndrome
what might recurrent dislocations require
soft tissue repair
reconstruction
occasionally bony surgical procedures
what is fracture dislocation
when fractures occur with dislocation
what are the types of ligament ruptures
1- sprain
2- partial tear
3- complete tear
what is the mainstay of treatment for soft tissue injuries
RICE- rest, ice, compression, elevation
why do you elevate a soft tissue injury
to reduce initial swelling
why should you have early movement in a ligament injury
to prevent stiffness
what do some complete ligament ruptures need
repair, tightening, graft reconstruction
what tendons when completely torn require surgical repair
ones fundamental for function- quads tendon, patellar tendon
what complete tendon tears can be treated conservatively
achilles, rotator cuff, long head of biceps brachii, distal biceps
what tendons can commonly divided with penetrating incised wounds
flexor and extensor tendon injuries in the hand and wrist- require surgical repair
what are the presenting features of septic arthritis
acute onset of a severely painful, hot, swollen and tender joint with severe pain on any movement
how does an infection get into a joint
spread by blood, adjacent tissue, direct penetration, intra articular surgery
why is early diagnosis of septic arthritis important
as bacterial infections can irreversible damage hyaline articular cartilage within days
what should be looked for if more than one joint is affected by septic arthritis
endocarditis (septic emboli)
list the bacteria known to commonly cause septic arthritis
S aureus - adults streptococci- 2nd most common haem influenza- children neisseria gonorrhoea- in YA e coli- elderly, IVDU, seriously ill
what is the treatment for septic arthritis
aspiration before antibiotics given (if frank pus aspirated then defos SA) to confirm diagnose, choose best antibiotic
surgical wash out (open/ arthroscopic)
antibiotics
response measured by clinical findings and CRP
