Principles of fracture Flashcards
Mechanism of fracture pattern
- Twisting causes a spiral fracture.
- Compression causes a short oblique fracture.
- Bending causes triangular‘butterfly’ fragment.
- Tension tends to break the bone transversely; in some cases it may simply avulse a small fragment of bone at the points of ligament or tendon insertion.
How to describe fracture displacement
Translation- shifted sideway, backward or forward in relation to each other
Angulation- Tilted in relation to each other
Rotation- Twisted around its longitudinal axis
Length- fracture distracted/ overlap causing shortening of bone due to muscle spasm
Cons of primary bone healing
Long period bone depends entirely upon metal implant, risk of implant failure
Implant drive stress away from bone, which. may become osteoporotic and may not recover fully until metal is removed
Stages of secondary bone healing
Haematoma formation
Inflammation
Soft callus formation- after 2-3 weeks
Hard callus formation- 3-4 months
Remodelling- few month to several years
Type of internal fixation
Interfragmentary lag screw
Plates and screws
Intramedullary nails
Type of plates
Complication of fracture
Early complication
- Visceral injury
- Vascular injury
- Nerve injury
- Compartment syndrome
- Haemarthrosis
= Infection
- Gas gangrene
Late
- Delayed union
- Non union
- Malunion
- AVN
What is Volkmann’s ischemic contracture
When muscle infarcted and nerve can never recover and is replaced by inelastic fibrous tissue
Regions that are notorious for developing bone necrosis after injury
Head of femur
Proximal part of scaphoid
Lunate
Body of talus
What is CRPS
Late stage of post traumatic reflex sympathetic dystrophy / algodystrophy
Type 1: reflex sympathetic dystrophy that develops after injurious
type 2: Causalgia that develops after nerve injury
Pathomechanism of stress fracture
Occur in normal bone due to repetitive stresses eg: bending and compression
= Bending cause deformation, osteoclastic resorption exceeds osteoblastic formation and zone of relative weakness develops and leading to breach in codex eg: gym
- Compressive stresses act on soft cancellous bone
Causes of pathological fracture
Generalised bone disease
- Osteogenesis imperfecta
- Post menopausal osteoporosis
- Metabolic bone disease
- Paget’s disease
Local benign
- Chronic infection
- Solitary bone cyst
- Aneurysmal bone cyst
- Chondroma
Primary malignant
- Chondrosarcoma
- Osteosarcoma
- Ewing tumour
Metastatic tumours
Classification of physical injury
SALTER HARRIS
Type 1: Separation of Epiphysis. Transverse fracture through hypertrophic or calcified zone
Type 2: Through physics and metaphysis. most common. AKA Thurston Holland fragment
Type 3: Intraarticular fracture of epiphysis. Damage reproductive layers of physics and result in growth disturbance
Type 4: Splitting of physics and epiphysis. Extends into metaphysis, asymmetrical growth
Type 5: Longitudinal compression injury of physics, no visible fracture by growth plate is crushed and result in growth arrest
Physical injury in Xray
Widening of physical gap, incongruity of joint, tilting of epiphyseal axis
What is apprehension test
Stressing at joint to almost to reproduce suspected dislocation; patient develops sense of impending disaster and violently resists further manipulation
