8: Open Fractures & Fracture Healing Flashcards
define an open fracture
when there is direct communcation between the fracture site and external environment
- most often through the skin but pelvic fractures can also internally open by penetrating the vagina or rectum
how might a fracture become open
- ‘in-to-out’ injury: sharp bone penetrates the skin from beneath
- ‘out-to-in’ injury: high energy injury penetrates the skin and traumatises the subtending soft tissues and bone
what are the most common sites of open fractures
- tibia
- phalanges
- forearm
- ankle
- metacarpals
what are the 4 outcomes of an open fracture
- skin: very small wound to significant tissue loss where plastic surgery intervention is needed i.e. skin grafting or local/free flap
- soft tissue
- neurovascular: nerves/vessels may be decompressed due to limb deformity - arteriospasm
- infection: rate of infection v high due to direct contamination, reduced vascularity, systemic compromise + need for metalwork insertion
how will patients with an open fracture present
- pain
- swelling
- deformity
- overlying wound or punctum
what is the initial management of an open fracture
- O/E, check neurovasc status and overlying skin for losses
- deal with evidence of contamination
- identify need for plastic surgery early on
- urgent realignment and splinting of limb
- broad spectrum abx + tetanus vaccination
- photograph wound and debride, wash and dress with saline soaked gauze
how are open fractures classified
Gustilo-Anderson classification
* Type 1: <1cm wound and clean
* Type 2: 1-10cm wound and clean
* Type 3A: >10cm wound and high-energy, but with adequate soft tissue coverage (ortho only)
* Type 3B: >10cm wound and high-energy, but with inadequate soft tissue coverage (plastics)
* Type 3C: All injuries with vascular injury (vascular)
what investigations do all patients with suspected open fractures require
bloods incl clotting screen and G&S
- plain radiograph
- comminuted or complex fractures may require CT
what is the definitive management of an open fracture
debridement of the wound and fracture site to remove all devitalised tissue
- should be immediate if contaminated with marine, agricultural or sewage material
- 12-24hrs in all other cases
- skeletal stabilisation
what are the 5 stages of fracture healing
- Haemostasis: mins to hours after injury, vasospasm of adjacent vessels, platelet plug formation, generation of fibrin
- Inflammation: days 1-5, neutrophilsl migrate into wound (function impaired in diabetes)), growth factors released including basic fibroblast growth factor and vascular endothelial growth factor, fibroblasts replicate within the adjacent matrix and migrate into wound, macrophage ad fibroblasts couple matrix regeneration and clot substitution
- Regeneration: days 7-56, platelet derived growth factor and transformation growth factors stimulate fibroblasts and epithelial cells, fibroblasts produce collagen network, angiogenesis occurs and wound resembles granulation tissue
- Remodelling: 6weeks-1year, longest phase, fibroblasts become differentiated and facilitate wound contraction, collagen fibres are remodelled, microvessels regress leaving pale scar
what are local factors affecting fracture healing
-
blood supply: reduced can lead to delayed union or non-union
- bone blood supply should also be considered e.g. IM nails compromise 50-80% endosteal circulation
- looser fitting nails will allow better endosteal reperfusion
-
fracture characteristics: extensive soft tissue damage can delay union
- segemental/buttergly fragment fractures have higher chance of non-union - infection
Which medication will slow bone healing after a fracture
- NSAIDs: COX enzyme inhibitions
- steroids
- immunosuppressive agents
what are the 3 important steps of fracture management
reduce
hold
immobilise
describe the reduction stage of fracture and what it allows for
restores anatomical alignment of fracture or dislocation of deformed limb
- tamponade of bleeding at fracture site
- reduces traction of surrounding tissues and therefore swelling
- reduces pressure on traversing blood supply so restores blood supply
describe the hold stage of fracture and what it allows for
immobilises fracture using simple splints or plaster casts
- for the first 2 weeks, plaster casts are not circumferential to reduce risk of compartment syndrome to allow swelling
- if axial instability (if fracture can rotate along its long axis) then plaster should cross both joint above and below
- important to remember about thromboprophylaxis and education about symptoms of compartment syndrome
