SA Fractures 3

Question 1

Evaluation of fracture healing.

Answer 1

3 A’s immediately post op:
- Alignment – leg straight.
- Apposition – fracture surfaces apposed.
– Apparatus – implant position, loosening, breakage etc.
4 A’s for later x-rays add:
- Activity – callus, fracture healing.

Question 2

Considerations for post op care of fractures.

Answer 2

Bandage - reduce swelling and increase comfort.
Restrict exercise - house/cage/4-6w.
Analgesia - opioids, NSAIDs.
Recheck(s) - x-ray every 3-6w.
Once healed - gradual return to normal exercise.
Px - guarded for articular, good for diaphysis.
Complications - infection, delayed or non union, malunion, refracture, implant complications.
– breakage, loosening etc.

Question 3

Open fracture classification.

Answer 3

Grade I - small puncture wound (<1cm) caused by bone puncturing skin.
Grade II - wound (>1cm) larger skin wound caused by external trauma.
Grade III - extensive loss of skin and bone often severe fractures.

Question 4

Why is an open fracture classed as an orthopaedic ‘emergency’?

Answer 4

Tissue devitalisation, ischaemia, FBs all promote a contaminated wound becoming infected.

Question 5

Managing open fractures.

Answer 5

Institute haemostasis.
Cover wound with sterile dressing.
Wear sterile apparel.
Apply water soluble gel to wound.
Clip hair.
Flush wounds with large volumes of saline (water).
Take bacterial swab.
Apply sterile dressing and bandage/splint.
Dress w/ non-adherent.
Wet to dry swabs.
Debridement:
- GA / sedation.
- remove dead fat and muscle (and skin).
- Preserve tendon, ligament, nerves, blood vessels, bone.
- Serial debridement over several days.
Stabilise:
- ESF – open grade I and III.
- simple grade I - internal fixation methods?

Question 6

The ‘golden’ period for open fractures.

Answer 6

Operate within the first 6-8hrs.
Perform adequate debridement and lavage.
Open fracture can be treated as a closed fracture e.g. w/ internal fixture.
Bacteria not had enough time to proliferate.

Question 7

1. What is osteomyelitis?
2. Osteomyelitis aetiology?

Answer 7

1. Any inflammatory condition of the bone / marrow / periosteum.
2. Sources of infection:
   - iatrogenic following surgery 70%.
   - haematogenous – endogenous.
   - extension from local lesion.
   - external source (bite wound).
   - Open fracture.
   - nosocomial (infection acquired during hospitalisation).

Question 8

Osteomyelitis - aetiopathogenesis…
1. sequestrum.
2. involucrum.

Answer 8

1. A necrotic bone fragment.
   Radiographically appears as a dense area of bone with sharp well defined edges.
2. The body attempts to wall off sequestrum by an avascular wall of fibrous tissue and sclerotic bone.

Question 9

Clinical signs of osteomyelitis.

Answer 9

Acute:
- Hx e.g. recent surgery, fracture repair.
- Pain, swelling, pyrexia, lameness, abscess.
- no bony changes radiographically, just soft tissue swelling.
Chronic:
- Hx (prev. Sx months or years ago).
- less severe clinical signs:
– lameness, pain.
– discharging sinuses.
- radiographic changes evident.

Question 10

Dx of osteomyelitis.

Answer 10

Radiographic changes:
- soft tissue swelling.
- periosteal bone.
- lucencies.
- disuse osteopenia.
- sequestra and involucrum.
- loose implants.
Causative organisms:
- bacteria.
– S. aureus, strep, E.coli, proteus, pasteurella, pseudomonas, nocardia, mycobacteria.
- fungi.
– cryptococcus, aspergillus.

Question 11

Treatment of acute osteomyelitis.

Answer 11

ABX:
- obtain sample for C&S.
- treat for 6w.
- repeat culture 3-5d after end of course.
Assess and address fracture stability.
Debridement.
Drainage.

Question 12

Treatment of chronic osteomyelitis.

Answer 12

Identify cause and remove.
- sequestrum.
- implants.
Lavage.
Primary or secondary closure.
Bacterial culture.
Assess fracture stability.

Question 13

Glycocalyx.

Answer 13

Implants may be covered by a gelatinous mucinous carbohydrate layer where bacteria can lie dormant and protected from abx.
All implants may need removal for infection to resolve.

Question 14

Delayed or non union.

Answer 14

Delayed union - fracture has not healed in the time normally expected for that type of fracture to heal.
Non union - fracture healing has stopped and union will not occur without surgical intervention.
*consider - age, breed, spp, bone affected and level, fracture type, soft tissue injury, method of fixation.

Question 15

Aetiopathogenesis of delayed union / non union.

Answer 15

Loss of blood supply.
Inadequate immobilisation.
General factors.
Inadequate reduction.
Infection.
Loss of bone.

Question 16

Clinical signs of delayed union / non union.

Answer 16

Motion at the fracture site.
Pseudoarthrosis (false joint).
Progressive deformity.
Disuse of limb.
Muscle atrophy.
Joint stiffness.

Question 17

Dx of delayed and non union.

Answer 17

Imaging:
- radiolucent gap.
- feathery appearance and moderate / no callus.
- sealed medullary canal.
- rounded fracture ends.

Question 18

Tx of delayed or non union.

Answer 18

Ensure no major nerve damage or fracture disease.
Provide rigid fixation.
Stimulate osteogenesis.
Treat infection.

Question 19

Malunion.

Answer 19

A fracture that has healed or is healing in an abnormal position.
Caused by improper immobilisation or reduction.
If malunion causes lameness / problems, may need to treat by osteotomising the bine and correcting malalignment.