Fracture Healing Flashcards
Fracture
Breach in continuity of bone
When do fractures occur
- non-physiological loads applied to normal bone
- physiological loads applied to abnormal bome
Describing fractures
Site
Pattern
Displacement/angulation
Joint involvement
Skin involvement
Describing fractures - site
Bone
Part of bone - proximal, middle , distal
Describing fractures - patterns
Transverse
Oblique
Spiral
Comminuted
Segmented
Avuksed
Impacted
Torus
Greenstick
Describing fractures - displacement/angulation
Displacement %
Angulation of distal part
Describing fractures - joint involvement
Extra-articular
Intra-articular
Describing fractures - skin involvement
Open/closed
Open fracture
Breach in skin
-orthopaedic emergency
- requires urgent treatment
- soft tissue injury determines outcome
Fracture patterns unique to children
Epiphyses open and bone more plastic
Heal quickly
Increased deformity remodelling
Fracture healing stages
Haematoma
Inflammation
Repair
Remodelling
Fracture healing - haematoma
Bleeding - endosteal and periosteal vessels, muscles etc
Decreased blood flow
Periosteal stripping
Osteocyte death
Length of haematoma stage of fracture healing
Hours
Fracture healing - inflammation
Fibrin clot organisation - platelets rich in chemo-attractants
Neovascularisation
Cellular invasion
- haematopoeitic cells = clear debris and express repair cytokines
- osteoclasts = resorb dead bone
- mesenchymal stem cells = form osteoblasts for repair
Function of haematopoeitic cells in inflammation
Clear debris
Express repair cytokines
Function of osteoclasts in inflammation
Resorb dead bone
Function of mesenchymal stem cells in inflammation
Differentiate into osteoblasts for bone repair
Length of inflammation stage of fracture repair
Days
Fracture healing - repair
Callus formation
Progressive matrix mineralisation
High vascukarity
Callus formation
Fibroblasts produce fibrous tissue (high strain)
Chondroblasts form cartilage (strain <10%)
Osteoblasts form osteoid (strain <1%)
Length of repair stage of fracture healing
Weeks
Fracture healing - remodelling
Woven bone structure replaced by lamellar bone - osteonal remodelling
Increased bone strength
Vascularity returns to normal
Healing without scar- unique
Length of remodelling stage of fracture repair
Months to years
Principles of fracture management
Reduce the fracture
Immobilise the part
Rehabilitate the patient
Types of fracture fixation
Slings
Casts and splints
Extra-medullary devices- plates and screws
Intra-medullary devices- nails
External fixation
Factors the influence fracture healing - patient
Age
Nutrition
Smoking
Drugs – NSAIDs, steroids
Factors the influence fracture healing - tissue
Bone type: cancellous vs. cortical
Bone site: upper limb vs. lower limb
Vascularity / soft tissue damage
Bone pathology - # in metastatic deposit does not heal
infection
Factors the influence fracture healing - treatment
Apposition of fragments
Stability (ability to resist force without deforming)
Micromotion (<1mm)
Types of fracture complications
Early/late
Local/general
Early local fracture complications
Vessel damage
Nerve damage
Compartment syndrome
infection
Early general fracture complications
Hypovolaemic shock
ARDS
VTE
Fat embolism
Late local fracture complications
Malunion
Non-union
Avascular necrosis
Ischaemic contractures
Joint stiffness
Myositis ossificans
Complex regional pain syndrome
Osteoarthritis
Late general fracture complications
Poor mobility
Functional disability and social isolation
Pressure sores
Disuse osteoporosis
Loss of income / job
Myositis ossificans
reaction to a bruise in a muscle that has been injured. During the healing of the bruise, calcium can become deposited in the bruise causing a hard bone like structure within the muscle.
