Ortho unit 5

Question 1

Periosteum

Answer 1

membrane which covers the outside of bones- has a nerve supply

Question 2

Immediate consequences of breaking a bone

Answer 2

Pain (nerve supply), blood loss- early management of fracture must minimise both of these consequences. Blood supply must be reestablished for bone to heal.

Question 3

What helps surgeon decide appropriate treatment

Answer 3

Condition of blood vessels

Question 4

Clinical aspects of history after trauma

Answer 4

What happened, how did it happen, where and when, what was the injured person like before it happened- full history, who is the person- social history
Medico-legal aspects- keep meticulous notes

Question 5

Signs of a fracture

Answer 5

Pain
Deformity- position of distal fragment determined by gravity, proximal part determined by attachment of the muscles
Tenderness
Swelling- injured part elevated to reduce swelling
Discolouration or bruising- can age injury
Loss of function
Crepitus- grating feeling when examining an injury

Question 6

Investigating fractures

Answer 6

X rays- usually 2 views- sagittal and coronal planes
Tomogram- view of slice through part of the body - useful where an area is difficult to distinguish die to overlapping structures
CAT scanner- computerised axial tomography
Ultrasound- can show accumulation of fluid
Radioisotope scanning-

Question 7

Radioisotope scanning

Answer 7

injecting radioactive substance into the bloodstream of an injured person- attaches to phosphate molecules which are actively taken up by bone- radioactive substance therefore ends up in bones. X ray plate is exposed to affected part of body and radiograph of bone is obtained. More metabolically active the bone is, the faster it takes up the radioactive substance. Sites of unusual metabolic activity can clearly be seen on the radiograph
Helpful in determining if a bone is fractured or not, if there is clinical doubt. More useful in non acute situations. Highly sensitive but doesn’t tell us anything about the fracture other than the fact that its there.

Question 8

What suspected fracture is radioisotope scanning useful for

Answer 8

scaphoid bone fracture

Question 9

Describing fractures

Answer 9

Which bone is broken and on which side
Open or closed fracture
Where on the bone is it broken (intra articular, mid shaft, proximal etc)
What shape is the fracture- spiral, oblique, transverse
How many fragments- simple, butterfly, comminuted
Position of the distal fragment- position of distal fragment described relative to the proximal one-
Displacement, angulation, rotation
Could it be a pathological fracture

Question 10

What causes spiral fractures

Answer 10

Twisting, little soft tissue damage so the blood supply to the bone is preserved

Question 11

what causes oblique and transverse fractures

Answer 11

bucking or direct injury to the bone

Question 12

Displacement

Answer 12

anterior, posterior, medial or lateral

Question 13

Angulation

Answer 13

anterior, posterior, varus or valgus

Question 14

Rotation

Answer 14

internal or external

Question 15

Immediate management of fracture

Answer 15

Pain relief-
Pain killing drugs- injections of morphine or pethidine
Splintage- splint should encompass the joint above and below an injury. Alternative to splint is traction- may be used in early treatment to relieve muscle spasm - particularly useful in fractures of femoral neck

Question 16

Blood loss

Answer 16

significant in major long bone fractures, particularly the femur. Major pelvic fractures, particularly if unstable, are associated with major venous bleeding from the pelvic plexuses- blood loss can be considerable- amounting to 6 units or so. In general, all patients with major long bone injuries should be cross matched for blood and a good size venous line for blood transfusion should be established ASAP. For pelvic fractures, 2 lines may be needed and a central venous line should be established to ensure transfusion is keeping up with loss

Question 17

Open fractures

Answer 17

Skin is broken. More violent injuries and result in bone being contaminated by bacteria from the environment. Treatment strategy is to clean out fracture and remove all dead tissue to prevent a contamination becoming an infection.

Question 18

Open fracture

Answer 18

surgical emergency- patient should be taken to the operating theatre ASAP- wound extended surgically and all debris and suspected dead tissue removed- exploration down to bone. Wounds either left open if theres any doubt that closure can be achieved without tension on the skin. This means that the vast majority of woulds should be left opened and closed either as a secondary procedure after a few days or left to heal spontaneously. Patient s all need supplementary broad spectrum antibiotics and some form of tetanus protection

Question 19

Definitive management of fractures

Answer 19

functional requirements vary from individual to individual

Question 20

Reduction

Answer 20

restoration of fracture to normal position
Closed reduction may be achieved by traction on the distal fragment and then a relocation of the distal part back onto the proximal fragment by manipulation. Adequate analgesia necessary to achieve a reduction
Open reduction may be required whereby the fracture site is opened surgically and the fragments are relocated directly under vision

Question 21

Holding

Answer 21

Once fracture is realigned - it myst be held in the desired position until the bone has become strong enough to support itself (united) and then protected until it is strong enough to bear load (consolidated)

Question 22

How can fractures be held in place

Answer 22

Casting
External fixation- external bar outside the body attached to pins sited in the broken bones
Internal fixation- holding bones together using plates and screws inside the body
Traction- pulling on broken limb to realign the bones

Question 23

Casting

Answer 23

Hold limb in plaster of paris cast until union- fracture must be held in the correct position by the cast and it must be maintained at the proper length. Cast must immobilise the joints above and below the fracture site, as joint movement may result in distortion in one or more dimensions. Cast acts as a splint- pressure is exerted at 3 points holding the bone in the correct position until it heals.

Question 24

Disadvantages of casts

Answer 24

Many- heavy and immobilise the joints.
Clinicians can’t examine the covered part or use X ray
Immobility results in muscle wasting and limited mobility due to joint stiffness

Question 25

Functional brace

Answer 25

Frees the joint. Necessary to support the cast at the joints by a combination of accurate moulding and the provision of hinges, which permit motion in one direction, usually flexion and extension, in order to maintain 3D control of the fracture Braces are highly dependent on a very accurate fit and so tend to be used after a few weeks, when pain and swelling have settled

Question 26

modern casting materials

Answer 26

Plaster of paris- brittle, hard to apply, heavy and awkward, takes up to 3 days to dry. New materials- based on glass fibre and polyurethane resin combinations- make ideal cast braces

Question 27

External fixation

Answer 27

High energy fractures- associated with extensive soft tissue damage, which often results in breaching of the skin or even loss of soft tissue. In such cases, because the blood supply is severely damaged, its important to have an initial phase of soft tissue healing. Plaster splits are unsuitable. Internal fixation is hazardous because of ischaemia and wound contamination increases the risk of infection being introduced during surgery. Compromise- device which is fixed to the bones by pins and which stabilises the limb by means of an external scaffold.. It provides stability of the bones and allows access to the soft tissues for dressings and secondary surgery such as skin grafting.

Question 28

Internal fixation

Answer 28

Used where a high degree of accuracy is required, or other methods fail. Involves holding of the fractured bone with devices such as screws, nails or plates.

Question 29

Ways to achieve internal fixation

Answer 29

Apposition Inter fragmentary compression Inter fragmentary compression plus only device Inlay device

Question 30

Apposition

Answer 30

Once fractures are realigned they may only need to be held in apposition (together in alignment) for healing to proceed. Particularly true in children- semi flexible K or Kirschner wires- hold position without producing immobility so healing occurs by natural callus formation. Can be left standing proud of the bone and so can easily be pulled out once union is established

Question 31

Inter fragmentary compression

Answer 31

Firmly holding 2 bone fragments together- usually achieved by screws or occasionally by tension band wires. Achieve great accuracy and are particularly valuable in cancellous bone around joints. Also useful in ling bones, particularly in the upper limb- in these situations extra support is requires from an only device.

Question 32

Only devices

Answer 32

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 generally not strong. They inhibit natural bona union, although they provide early movement of the whole leg, they ultimately delay healing and full load bearing because they inhibit the natural healing by eliminating micro- movement at the fracture sire

Question 33

Inlay/intramedulary devices

Answer 33

In many ways the most satisfactory method of fixation. Achieve the correct alignment of the broken bones without unduly disturbing the natural bone healing. Relatively inaccurate method of restoring anatomical position- not useful around joints. Great strength makes them ideal for treating long bone fractures, esp in lower limb. If fractures are badly comminuted or rotated- cross screws can be inserted into the bone using an x ray image intensifier to show the bone and nail during surgery

Question 34

Removal of implants

Answer 34

Whether internal fixation devices should be removed or not - controversial. Bone next to fixation device is weaker as it shares the load with the fixation device. The adjacent unsupported bone is normal- boundary created between normal bone and weak, fixed bone leading to stresses at the abnormal/normal bone interface. Probably safest to remove implants in young people.

Question 35

Traction

Answer 35

Can be used to hold a reduction. As a holding device- application of relatively small weight to a limb (5kg at most), which exerts a pill along the axis of the broken limb- stimulates muscles to contract. This small contraction of muscle is sufficient to hold a broken bone in position (as muscles surround the bone).

Question 36

Types of traction

Answer 36

static dynamic balanced

Question 37

Static traction

Answer 37

Relatively short periods, pull is applied against another part of the body. Thomas splint- pull applied against the ring which presses against the pelvis.

Question 38

Balanced traction

Answer 38

used where static traction is in danger of causing damage to a part of the body through pressure. Here, pull against the ring and this the pelvis is balanced by a weight attached to the whole splint- takes pressure of the skin while maintaining traction on the leg

Question 39

Dynamic traction

Answer 39

Traction applied using strapping stuck on to the skin. Weights used aren't large and are only applied for a few days. Particularly

Question 40

when is dynamic traction particularly useful

Answer 40

when traction is being used to relieve pain, such as following a fracture of the femoral neck- results in change in muscle tone, relieving muscle spasm and diminishing need for pain killing drugs.

Question 41

Long term traction requiring larger weights

Answer 41

Pin inserted through the bone is preferable and easier to manage- pins can be problematic if they loosen and/or become infected- regular nursing required.

Question 42

When is traction freq used

Answer 42

fractures of the femur where splint age to include the hip joint is impractical. Also useful when there is a large degree of soft tissue damage.

Question 43

Main problem with traction

Answer 43

Patient must remain in bed- making hospital stay prolonged and nursing care difficult

Question 44

How do bones heal

Answer 44

Bone tissue can be regenerated after injury. They heal in the presence of some movement. Bones are stimulated to heal by micoromovement 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. Without this movement- bones heal very slowly

Question 45

Stages of bone healing

Answer 45

``` First 2 weeks- swelling 2-6 weeks- callus forming 6-12 weeks- bone forming 6-12 months- bone 1-2yrs- remodelling has taken place and the bone returns to normal ```

Question 46

What is all bone healing dependent upon

Answer 46

Good blood supply

Question 47

What happens when bones are fixed rigidly e.g. internal fixation

Answer 47

they will heal slowly

Question 48

Low energy injuries

Answer 48

Most fractures to shafts of long bones are cause by a low velocity impact- relatively little soft tissue damage and greater fracture stability- can be treated with manipulation and casting (providing holding is possible)- if holding is an issue e.g. femur- traction may be used, Internal fixation may be justified is this leads to early mobilisation of the injured person

Question 49

fractures involving joints

Answer 49

Great deal of internal fixation is justified if the fracture is displaced. Around joints where cancellous bone tends to be fragmented and often with little soft tissue support, holding requires accurate reconstruction of the fragments- usually with screws to aid stability

Question 50

High velocity injuries

Answer 50

Require special attention whether opened or closed- due to damage to blood supply. External fixators- particularly valuable in this type of injury

Question 51

Why are fractures in elderly commonly held using internal fixation techniques

Answer 51

to permit early mobilisation and thus a return to normal function as soon as possible

Question 52

Early primary (as a consequence of injury) complications

Answer 52

``` blood loss infection fat embolism renal failure soft tissue injury compartment syndrome ```

Question 53

Early secondary (as a consequence of treatment) complications

Answer 53

``` plaster disease renal stones immobility infection compartment syndrome ```

Question 54

Late primary complications

Answer 54

``` non union delayed union mal union growth arrest arthritis ```

Question 55

late secondary complications

Answer 55

mal union | infection

Question 56

Infection

Answer 56

after open fractures or internal fixation. Provided a fracture is held stable- it will unite despite infection. If an open fracture that isn't stable or an unstable fixed fracture becomes infected- stabilisation by internal fixation followed by surgical wound cleansing and later bone grafting will be required

Question 57

Fat embolism

Answer 57

Not common, found typically after the fracture of a long bone in men under 20yrs old.

Question 58

Symptoms of fat embolism

Answer 58

Commence within 2-5 days from injury- may initially present as rapid shallow breathing (tachypnoea) and mild confusion. Injured person may have a rash on their chest and neck. Severe cases- res distress increases to the point where ventilation is required- even with support- condition carries significant mortality. Younger men more prone to full blown condition.

Question 59

Treatment of fat embolism

Answer 59

high percentage oxygen, chest physio. Steroids given early or even prophylactically are said to reduce the severity- remains controversial. Early diagnosis- essential

Question 60

Renal failure

Answer 60

People with massive soft tissue injuries who are trapped for prolonged periods- particularly when limbs are ischaemic are prone to develop kidney failure. Myoglobin is found in abundance in the kidneys of people who die from this

Question 61

compartment syndrome

Answer 61

Volkmanns ischamia. Following fracture with excessive localised soft tissue swelling- classically in forearm or calf. All muscles are surrounded by fascia, groups of muscles surrounded by fascial sheath. Sheath supports the muscles and gives them shape swell as anchoring them to bone and surrounding soft tissues. Fascial sheets act as boundaries between groups of muscles- creating compartments.

Question 62

Compartment syndrome cause

Answer 62

Fracture occurs- bleeding into adjacent compartments and swelling from inflammatory reaction- leading to increase in pressure within the compartment. This rise in pressure can reduce blood flow locally to the tissues- results in ischaemia. Rarely- compartment syndrome can occur without fracture- shin splints?

Question 63

Compartment syndrome symptoms

Answer 63

Pain- out of proportion to the injury. Loss of function of the muscles and often altered sensation over the compartment. Pulse distal to the compartment is normal. Diagnostic test- stretch the muscles of the compartment- should precipitate extreme pain

Question 64

Intervention for compartment syndrome

Answer 64

Remove dressing and split plasters. If this fails- surgical intervention is inevitable. Condition can be prevented by early elevation of injured limb

Question 65

Immobility

Answer 65

People must begin to mobilise and rehab as soon after the injury as possible.

Question 66

Fracture diease

Answer 66

Muscle wasting and skin sores

Question 67

What does early mobilisation discourage the development of

Answer 67

``` Osteoporosis renal stone formation- caused by calcium from the thinning bone stiffness muscle wasting skin sores ```

Question 68

Non union- most common site

Answer 68

tibia

Question 69

Non union- contributing factors

Answer 69

excess movement, too little movement, soft tissue interposition, poor blood supply, infection, excessive traction or splinting of bones too far apart, intact adjacent bone.

Question 70

When is non union said to occur

Answer 70

when injured person and/or surgeon feels that the healing has taken to long- 20 weeks in lower limb and 10 in upper

Question 71

How long should it take for fractures to heal in upper and lower limb

Answer 71

upper- 6weeks | lower-12 weeks

Question 72

delayed union

Answer 72

less specific- period between expected union and accepted non union

Question 73

treatment for non union

Answer 73

removing underlying cause- then stimulating union Stabilising the fracture sufficiently then adding a bone graft seems to stimulate the union Bone graft- usually autologous (taken from bone of same individual) and placed next to fracture- switches on the hitherto deficient healing mechanism

Question 74

mal union

Answer 74

fracture has been allowed to heal in a position that precludes normal function. Once recognised- may be treated by open reduction and internal fixation

Question 75

Growth arrest

Answer 75

If fracture breaches the germinal layer of the epiphyseal growth plate- bone growth may be arrested at the point of breach- resulting in deformity. Rare injuries and difficult to manage. Children have great capacity to remodel mal united fractures- although they will not remodel rotary deformities

Question 76

arthritis

Answer 76

will develop secondary to a fracture if a joint is excessively stresses- likely if a fracture goes across a joint and disturbs the surfaces sp that the joint is no longer congruent, Occasionally- direct damage to articular cartilage will result in arthritis