MSK Trauma - fractures Flashcards
Define fracture.
A break in the continuity of the bone.
Initiates a complex tissue repair process through bone death or damage to periosteum and blood vessels.
What groups may experience a complicated fracture repair process?
Osteoporosis
Diabetes
Infection
Diminished blood supply to area
older patients
outline the process of fracture repair:
- Vascular damage
2,. fracture haematoma - Fibrin mesh develops
- Granulation tissue containing inflammatory cells , fibroblasts, bone and cartilage forming cells.
- Precallus cartilaginous tissue forms and anchors ends of bone
- Osteoblasts form bony callus tissue collars broken end so healing can occur.
- Overtime callus tissue is replaced by normal bone as injury heals.
Define dislocation:
Complete loss of continuity of two bones forming joint.
Define subluxation:
Partial loss of continuity of 2 bones forming joint
Define open fracture:
A direct communication between the fracture and the external environment.
What are 3 causes of fractures:
- injury mechanism that exceeds maximum force bone can withstand (normal + abnormal bone)
- comorbidity that increased risk of fracture after injury
- Comorbidity that increases risk of injuries.
What are some congenital and acquired syndromes that increase risk of fracture after injury?
- Congenital e.g. osteogenesis imperfecta
- Acquired e.g.
metabolic such as rickets and osteomalacia or
degenerative like osteoporosis or tumours.
What are some types of complete fractures?
- Simple fractures: transverse, oblique, spiral
- Complex fractures
- Compression fractures
- extra/intra articular involvement.
What 3 things should you think about when requesting a radiograph?
- Specific area, XR joint, beam divergence
- 2+ views AP and lateral
- Special views to request e.g. mortise and scaphoid.
What is primary healing?
Primary fracture healing is direct healing without fracture callus, requires absolute stability hence only occurs in surgery. Haversian remodelling.
What is secondary healing
Secondary healing is all other types of fracture healing. Requires relative stability of fracture; endochondral ossification occurs involving inflammation repair and remodelling.
What happens in the inflammation stage of endochondral ossification?
haematoma and inflammatory cells, osteoblasts and fibroblasts proliferate, granulation tissue forms around bone edges.
What happens in the first repair stage of endochondral ossification?
New blood vessels and internal/external callus forms <2 weeks, primary soft callus is cartilage and is wider then bone contour for strength
What happens in the second repair stage of endochondral ossification?
Soft cartilage is replaced by woven bone (hard callus) which is produced rapidly but is disorganized and not stress oriented therefore weak.
What happens in the remodelling stage of endochondral ossification?
begins in the middle of repair stages. Woven bone is remodelled to laminar bone via cutting cones. Wolff’s law, stress orientated formation, and can take years.
What are 3 options for non-operative management and what are the positives and negatives of this?
- Nothing
- splints for comfort
- Devices to help control position
Positives: Cheap, easy to apply, no risks that are involved with operating.
Negatives: Stiffness, not fully controlled, pressure issues with casts and swelling, patient comfort.
What are the positives and negatives of operative fracture management?
Positives: Less immobilisation, earlier rehab and pain control, anatomical reduction and fixation prevents further disability especially when involving articular surfaces
Negatives: Expensive, may slow healing, risk of complications.
What are 3 features of high energy trauma?
- Poly trauma
- Complex and displaced fracture patterns
- Soft tissue injuries
What is the A->E assessment map for ortho trauma?
A - airway and c-spine control
B - breathing
C - circulation
D - disability
E - exposure
What is ATOM FC
reversible life threatening trauma:
A - Airway obstruction
T - Tension pneumothorax
O - Open pneumothorax
M - Massive haemothorax
F - Flail chest
C - Cardiac tamponade
What is important to remember in the ED management of open fractures? (6)
There is an increased risk of infection that could lead to infective non-union.
- Early ABX IV
- Anti tetanus jab if no within 5 years
- Splint or cast to connect length and alignment.
- tamponade bleeding vessel
- Sterile saline soaked dressing to cover wound
- Take a photo before dressing!!
How are open fractures managed in surgery?
- Sequential operations
- First for wound debridement and skeletal stabilisation
- Second for tissue inspection, further debridement and wound closure by plastics
What are the symptoms of compartment syndrome with a tibial shaft fracture?
- Serve pain that increases with severity
- Pain on passive stretching of toes
- Paraesthesia
- Normal pulses
- Muscles in calf feel tight
- PAIn disproportionate to injury
What is compartment syndrome? (3)
- Increased pressure inside fixed fascial compartment
- Results in reduced tissue perfusion, severe muscle pain from pressure ischemic
- Tissues in compartment go from ischemia to neurotic then become irreversible damaged and result in amputation.
What is the vicious cycle of compartment syndrome?
- injury leads to tissue swelling
- Increased compartment pressure
- Decreased perfusion pressure
- Local hypoxia
- Cell membrane damage
- Leads to increased tissue swelling.
Where are the most common locations for compartment syndrome to occur?
Leg, forearm and thigh but can occur anywhere in the fascial layer.
Give an example of how to describe a radiograph:
There is a (displaced/nondisplaced) fracture of the (proximal, midshaft, distal) bone (name)
Add qualifiers (complex, articular involvement, oblique, spiral, transverse)
Outline the process in primary fracture healing? (7)
- Cutting cones form at ends of osteons
- The tips of the cutting cones consist of osteoclasts.
- These tips cross the fracture line and generate longitudinal cavities
- The cavities are eventually filled by bone that is produced by osteoblasts.
- This causes the bony union to generate while also restoring Haversian systems, formed in an axial direction.
- The Haversian systems enable blood vessels carrying osteoblasts to enter the area.
- Bridging osteons eventually mature into lamellar bone.
What is the function of the central resorption cavity in haversian remodelling?
Products of bone resorption are secreted and osteoprogenitor cells can migrate freely.
Define what union means in fracture healing?
Union = hard callus has formed fully across the fracture
What is the healing time range for humerus and for distal radius fractures?
Humerus = 6-12 weeks
Distal radius = 5-6 weeks
What is the healing time range for ankle, tibia and femur fractures?
ankle = 6 weeks
Tibia = 12 weeks (variable)
Femur = 24 weeks
What is mal-union
When bone heals in a suboptimal position
What is a delayed union?
When bone heals but in longer than expected time frame
What is a non-union?
When fracture fragments remain separate
What are some patient related factors affecting fracture healing time?
Smoking
Alcohol use
Malnutrition
NSAID use
Comorbidities such as diabetes or vascular insufficiency
What are some fracture related factors affecting fracture healing time?
- Energy transfer of fracture
- Blood supply to bone
- Associated soft tissue injury
- Morphology
Which bone are particularly important when considering effect of blood supply on fracture healing times?
Scaphoid, talus, femoral and humeral heads.
What are some treatment related factors on fracture healing time?
- Adequate stability
- Adequate fixation
- Soft tissue dissection as too much strips periosteum
- infection with surgery
- Patient compliance
what are two known unstable fracture patterns?
ankle-talar shift and wrist volar displacement
What distinguishes stable from unstable fractures?
- Displacement under minimum physiological load
- Alignment of bones
- Soft tissue support
What are some absolute indications of operative management?
- Displaced intra-articular fractures
- Open fractures
- Pathological fractures
- Polytrauma to stabilize long bones
What is an important consideration with metatarsal fractures?
- Almost always from punching inanimate or animate object
- Fight bite needs to be treated as an open fracture.
