Fracture Overview
A fracture is defined as a break in the continuity of a bone.
Fracture Classification
Open vs Closed Fractures
| Fracture type | Description |
|---|---|
| Open fracture | The fractured bone creates direct communication between the bone and the external environment (i.e. the overlying skin is NOT intact)
Open fracture carries a higher risk of infection |
| Closed fracture | The overlying skin is intact, with no communication between the fracture site and the external environment (the fractured bone did not breach through the skin) |
Complete vs Incomplete Fractures
| Fracture type | Description |
|---|---|
| Complete fracture | The fracture line completely traverses the entire width of the bone, disrupting the cortex circumferentially (all the way around) |
| Incomplete fracture | The fracture line does not traverse completely through the bone, leaving one opposing cortex intact
More common in children |
Displaced vs Undisplaced Fractures
| Fracture type | Description |
|---|---|
| Displaced fracture | Any fracture that loses its normal anatomical alignment between the bone fragments
There are 4 main subtypes of displaced fracture (depending on how the fracture has moved out of place):
|
| Undisplaced fracture | The bone fragments remain in near-normal anatomical alignment |
Fracture Pattern
Fracture patterns are based on the visual geometric layout of the bone break:
| Fracture pattern | Definition | Typical mechanism of injury | Typical bone involvement |
|---|---|---|---|
| Transverse | Fracture line runs perpendicular to the long axis of the bone | Direct blunt force | Long bones (e.g. radius, ulna, tibia) |
| Oblique | Fracture line runs diagonally across the bone | Combination of bending and compression forces | Specific long bones (e.g. tibia, fibula, metacarpal / metatarsal) |
| Spiral | Fracture line twists around the shaft of the bone in a spiral / helical pattern
*It can be difficult to distinguish from an oblique fracture, especially on 2D radiographs |
Torsional / rotational twisting force | Specific long bones (e.g. tibia, fibula, metacarpal / metatarsal) |
| Avulsion | A bone fragment is pulled away from the main bone at the attachment site of a tendon or ligament | Sudden traction / pulling force | Occurs at tendon / ligament attachment sites (e.g. medial epicondyle of humerus, base of 5th metatarsal, ASIS, malleolus) |
| Comminuted | Bone is broken into more than 2 distinct fragments | High-energy crush or impact injury | Major long bones (e.g. femur, tibia, humerus) |
| Impacted | One bone fragment is driven into the adjacent fragment, causing the fragments to become wedged together | Axial loading along the long axis of the bone | Intracapsular NoF fracture, distal radius fracture, proximal humeral fracture, vertebral compression fracture |
Cause-Based Classification
| Cause | Definition | Examples |
|---|---|---|
| Traumatic fracture | Occurs due to an acute external force applied to normal, healthy bone | Falls, road traffic accidents, sports injury |
| Stress fracture | Occurs due to repetitive loading over time, causing microdamage to accumulate faster than bone can repair | Metatarsal stress fracture in a runner |
| Fragility fracture | Occurs after low-energy trauma that would not normally cause a fracture, usually due to reduced bone strength | Osteoporotic NoF or vertebral compression fracture |
| Pathological fracture | Occurs through abnormal bone that has been weakened by an underlying disease | Fracture through bone metastasis, primary bone tumour or bone cyst |
Paediatric Fracture Patterns
| Fracture type | Description |
|---|---|
| Greenstick fracture | An incomplete fracture where one side of the bone breaks while the opposite cortex bends |
| Buckle / torus fracture | An incomplete compression injury where the cortex buckles without a complete break through the bone |
| Physeal fracture | A fracture involving the growth plate. This is clinically important because growth plate injury may affect future bone growth
Classified using the Salter-Harris classification (higher grades are associated with more severe injuries):
|
Clinical Features
Fractures typically present as:
- Pain
- Swelling
- Tenderness
- Deformity
- Loss of function
- Reduced ROM
- Inability to weight bear (in lower limb fractures)
Assessment and Diagnosis
Clinical assessment:
- Assess distal neurovascular status
- Nerve injury suggested by change in sensory / paraesthesia / weakness
- Vascular injury suggested by delayed capillary refill time / weak pulse / cold skin
- Check for compartment syndrome (suggested by severe pain out of proportion or severe pain on passive stretch)
- Assess joint above and below
1st line investigation: plain X-ray
- If X-ray is inconclusive, CT may be considered (but not routinely necessary)
Complications
| Acute complications |
|
| Early complications |
|
| Long-term complications | Healing-related complications:
Other complications:
In children, fractures affecting the growth plate (physeal fractures) can affect future bone growth |
Management
General management principles:
- A-E assessment for major trauma
- Analgesia
- Immobilise the limb to prevent further soft tissue or neurovascular injury
- Reduction and/or fixation
Reduction and Fixation
Reduction and fixation are 2 related but separate management principles in orthopaedics:
- Reduction = attempting to restore the fracture fragments into anatomical position
- Fixation = keeping the fracture fragments in position while healing occurs
Types of reduction:
- Closed reduction: fracture is manipulated back into position without surgically exposing the bone (e.g. manipulation of a displaced distal radial fracture)
- Often followed by cast, splint, brace or sling
- Open reduction: fracture is surgically exposed to allow direct visualisation and realignment (e.g. managing a NoF fracture)
Types of fixation:
- Internal fixation: metal work is placed inside the body to hold the bone fragments in place (e.g. plates, screws, intramedullary nails, wires)
- External fixation: screws or wires are inserted through the skin directly into the bone fragment, which are then connected to a metal frame on the outside of the body
- Primarily used in severe fractures, fractures with extensive soft tissue damage, limb lengthening and deformity correction, temporary stabilisation (until oedema resolves and internal fixation can be safely performed)
Key indications for open reduction internal fixation (ORIF):
- Failed closed reduction
- Open fracture
- Unstable fracture
- Significantly displaced fracture
- Intra-articular fracture
- Neurovascular compromise
- Fracture-dislocation
- Multiple fractures / polytrauma
Open Fracture Management
Open fracture is an orthopaedic emergency due to infection risk:
- Urgent IV empirical antibiotics
- Check tetanus status (see the Tetanus Prophylaxis article for more information)
- Urgent orthopaedic referral for surgical debridement and washout