Ortho unit 5 Flashcards
history after a trauma
what happened - energy transferred determines injury to bone as well as soft tissue and extent to which blood supply is disrupted
how did it happen - injuries follow a pattern e.g. hit by a car - get certain injuries
where and when - may limit treatment
what were they like before the injury
who is the person
the signs of a fracture (8)
pain - never move suddenly and never without a splint
deformity - the position of the distal fragment of determined by gravity and the position of the proximal fragment by muscle. sometimes it is influenced by the direction of the force
tenderness - hurts when touched
swelling - excessive swelling is painful and makes recovery more difficult so elevate injured part (above heart)
discolouration/bruising - possible to age an injury. at first it is dark because of deoxygenated blood loss to the soft tissue. then as Hb in RBC is broken down and carried by scavenger cells to the liver, the colour changes to green then yellow.
loss of function
crepitus - patient wont appreciate you looking for this sign
injury to other tissues - skin, fat, blood vessels, nerves
investigating fractures
x rays - two views. sagittal and coronal
tomograms - slice through part of the body. modern machines use electronic detectors in place of x ray film. v useful where an area is difficult to distinguish because of many overlapping structures e.g. cervical spine hard to se from jaw and skull and teeth
computerised axial tomography - computers can be used to generate tomograms on a video screen. this technique is computer aided tomography (CAT)
US - show the resulting accumulation of fluid due to a fracture
Radioisotope scanning - inject radioisotope into blood, attaches to phosphate molecules which are taken up by bone. x ray then obtained. the more metabolically active the faster isotope is taken up so the sites of unusual metabolic activity can be seen. where there is clinical doubt this scan can help. more useful in non acute. highly sensitive - often used when a scaphoid fracture is suspected as its not easily seen on x ray at first.
describing fractures
which bone is broken and on which side
is it open or closed
where on the bone is it broken - intraarticular, mid shaft, prox, middle, distal
what shape
spiral - occur from twisting. common low energy injury. associated with little soft tissue injury so blood supply is preserved and healing isn’t an issue
oblique
transverse
oblique and transverse are caused by buckling or direct injury to the bone. it involves a lot of energy, resulting in soft tissue stripping and damage to blood supply so usually take longer to heal
how many fragments
butterfly
simple
comminuted
what position is the distal fragment - must be descried in three dimensions. position of the distal fragment described in relation to the proximal one - makes sense as proximal fragment takes position based on new muscle balanced so treatment is aimed at changing the position of the distal one.
describe the fragment in terms of
displacement - anterior, posterior, medial, lateral
angulation - anterior, posterior, valgus, varus
rotation - internal, external
could it be a pathological fracture? - fracture seems out of proportion to the violence of injury. suggests one is weak as a result of osteoporosis or cancer etc
immediate management
Pain relief
use of pain killing drugs - injection of morphine or pethidine
splint age - can relieve pain alone. encompasses the joint below and above the injury e.g. binding arm to the chest or binding two legs together. alternative to splint age is traction - may be used in early treatment to relieve spasm - major component of post fracture pain. particular useful of fractures of the femoral neck where splint age is impossible to apply
Blood loss
for most upper limb and peripheral lower limb fractures blood loss isn’t usually a major issue and is well tolerated even by the elderly. in major long bones e.g. femur and sometimes tibia major blood loss is an issue - fem fracture could lose 2-3 units of blood (tibia is 1 which is tolerable but with other injuries may become significant)
major pelvis fractures particularly if unstable are associated with major venus plexus bleeding from the venous plexuses - can lose 6 units. if combined with other injuries can be lethal unless replaced
all patients with major long bone injury need to be cross matched and a good sized venous line for blood transfusion needs to be established asap. for pelvic two lines may be needed and a central venous line should be established so transfusion is keeping up with loss.
Open fractures
skin broken
violent usually - result in bone being contaminated by bacteria from the environment
need to clean out and remove all dead tissue as soon as possible
SURGICAL EMERGENCY - all debris and suspected dead tissue removed. wide excision must be made to explore down to the bone - make sure no clothing ect is left
wounds are bettie left open if there is any doubt that closure can be achieved without tension on the skin - so majority are left to heal spontaneously or closed as a second procedure a few days later. thesis patents all need broad spectrum AB and some form of tetanus protection
Definitive management
the technique used after bleeding and pain have been controlled to restore normal function. will depend on the person, the injury and the surgeon
the person - everyone has diff functional demands e.g. old person with comorbidities inc osteoporosis may be treated to gain a less than perfect result e.g. by local anaesthesia in A+E, but they stay out of hospital so don’t get pressure sores , UTI, pneumonia etc. benefit must outweigh risk
RULES
if the fracture passes into a joint then the anatomy must be restored accurately if acceptable function is to be achieved.
if it occurs through the shaft of a log bone then the margin for error is larger and something less than perfect is acceptable.
restoration to the normal position = reduction - must be held here until the bone heals
- reduction
- holding
- traction
reduction
closed reduction may be achieved by traction of the distal fragment and then a relocation of that distal part back onto the proximal part by manipulation. need to take adequate analgesia, and general or regional anaesthesia may be used. if unsuccessful open reduction may be required
holding
once the fracture is realigned it must be held in position until the bone becomes strong enough to support itself - united, and then protected until strong enough to bear some load - consolidated.
may be held in place by cast, external fixation, internal fixation, traction
casting
plaster of paris until union, must be maintained at the proper length - too long may delay union. in order to ensure complete control of all dimensions the cast must immobilise the joints below and above the fracture. A plaster cast is moulded so that pressure is exerted at three points - plaster cast is moulded to mimic the direction of the reducing force. disadvantages: heavy and they immobilise joints, clinicians cant examine the covered part or use x rays so need to remove them to assess progress, immobility leads to muscle wasting and limited mobility due to joint stiffness. Braces can overcome the disadvantages of casts by freeing the joints. to maintain accurate 3 dimensional control of the fracture the cast must be supported by accurate moulding and the provision of hinges which permit movement in one direction - usually flexion and extension. they are v dependent on an accurate fit so are usually used after a few weeks once swelling and pain has settled. plaster of paris si brittle and messy and heavy, takes 3 days to dry. new stronger and lighter materials have been developed based on glass fibre and polyurethane resin combinations. they are not as versatile as plaster of paris so are used as a secondary cast a week or so after the injury once swelling has settled. they make ideal cast braces.
external fixation
in high energy fractures where there is soft tissue damage and often results in breaking of the skin, and blood supply is severely damaged its important to give the soft tissue time to heal. plaster splints are therefore unsuitable as the wounds become inaccessible. internal fixation is hazardous because of ischaemia and wound contamination increases a risk of infection being introduced during the surgery. a device which is fixed to the bones by pins and which stabilises the limb by an external scaffold has its attractions. it provides stability of the bones and allows soft tissue access for dressings and secondary surgery such as grafting. in the past external fixators were removed once soft tissue had healed and fracture was treated by other means, but now we can treat it definitely with the external fixator especially if it can be adjusted in the later stages to permit some movement (dynamisation). however it still has problems - pins are an easy route for infection
internal fixation
when a high degree of accuracy is required or other methods fail internal fixation of fractures is used. it holds the fractured bone together with plates/screws/nails. it is v demanding and has many complications - most importantly it prevents natural healing. it can be achieved in a number of ways
apposition - once fractures are realigned they need to be held in apposition (together). can be achieved by semi flexible wires - K wires. they hold position without causing immobility so healing occurs by natural callus formation - they can be left standing proud of the bone so can be pulled out once union is established and before consolidation.
inter fragmentary compression - holding two bone fragments firmly together. usually achieved by screws or sometimes tension band wires. achieve accuracy and are v valuable in cancellous bone around joints. also useful in long bones paretic in upper limb but in these situations extra support is needed by only device
inter fragmentary compression plus onlay device - onlay device consists of a plate of metal - used to buttress weak structures around joints and to fix long bones in the upper limb. may be used in lower limb but they are generally not strong and deffs cant be used in lower limb without inter fragmentary compression. these v rigid systems inhibit natural bone union and although they permit early movement of the while leg, they ultimately delay healing and full load bearing as they inhibit natural healing by eliminating micro-movement at the fracture site
inlay device - (intramedullary nail) most satisfactory method. achieve correct alignment without unduly disturbing natural bone healing. relatively inaccurate method of restoring anatomical position and so are not useful around joints. great strength mean they are good for long bone fractures esp lower limb. if fractures are commented or rotated then cross screws can be inserted into the bone by using x rays
following fixation the bone next to a fixation device is weaker, the adjacent non supported bone is normal so a boundary is formed between normal and weak, foxed bone leads to stresses at the boundary. long term risk of biological implants is unknown, disturbing reports of tumours arising around implants so probably safer esp in young people to remove implants - but this has risks of removing through scar tissue e.g. infection, damage to blood vessels and nerves
traction
using traction as a holding device involves the application of a small weight which experts a pull along the axis of the broken limb (at most 5kg), it stimulates the muscles to contract which will hold a broken bone in the position achieved at reduction (contrast to traction in reduction where a large force is used to overcome muscle resistance to achieve alignment). can be applied in a number of ways:
static - used for short periods, the pull is applied against another part of the body. in the thomas splint the pul is applied against the ring which presses against the pelvis
dynamic - used when joints are still permitted to move but by means of pulleys, the pull is still maintained along the line of the bone. weights provide the pull and the counter force is achieved by tilting the bed.
balanced used when static is in danger of causing damage to a part of the body through pressure. the pull against the ring is balanced by a weight attached to the whole splint taking the pressure off the skin around the ring while maintaining traction on the leg.
may be applied using strapping stuck onto the skin. weight used are only small and only applied for a few days - useful when its being used to relieve pain - results in change in muscle tone, relieving spasm and reducing need for pain killers
for long term traction needing larger weights, a pin inserted through the bone is preferable and in the long run easier to manage - but problematic if they loosen/infection. need regular nursing care to keep them dry and clean
useful where other external treatment methods are problematic. often used for fractures of the femur esp where splint age to include the hip joint is impractical. also useful alternative to external fixation when there is a large amount of soft tissue damage. the main problem with traction is that the injured person must remain in bed, making hospital stay prolonged and nursing care difficult
how fractures heal
bone tissue can regenerate unlike other connective tissues which heal with fibrous tissue forming a scar.
bones heal in the presence of some movement - it stimulates union but it just be small movement and only in certain directions. they are stimulated to heal by microenvironment directed along the long axis of the bone at right angles to the break. they heal least efficiently if subjected to shearing forces or large movements
first 2 weeks - swelling
2-6 weeks - callus formation
6-12 weeks - bone forming
6-12 months - bone
1-2 years - remodelling has taken place and the bone returns to normal
bones will heal if there is no movement - just v slowly and by a diff process which doesn’t involve natural callus formation but have v accurate alignment. most marked in long bones and less problematic in cancellous bone which tends to heal quite quickly.
all bone healing is dependent on good blood supply
management of low energy injuries
low velocity, little soft tissue damage, greater fracture stability. treated by manipulation and casting. if holding is a difficulty e.g. femur then traction may be used. other methods include functional bracing and internal fixation (justified if this leads to early mobilisation). if risk of op is low or benefit is high then fixation is generally justified.
management of fractures involving joints
generally need internal fixation if the fracture is displaced. reduction to the degree of accuracy needed for intra-articular fractures is unusual without operation. around joints where cancellous bone tends to be fragmented and often with little soft tissue support, cling requires accurate reconstruction of the fragments, usually with screws to aid stability
