This is a general introduction to fractures. The aim is to familiarise yourself with the process of identifying fractures, both clinically and radiologically, and understand the different management options available.
A fracture is defined as a disruption in bone continuity. The degree of disruption can vary from a crack in the cortex to multifragmentation. Fractures are often associated with local tissue trauma. Again, the severity can vary; from mild oedema to vascular compromise. Fractures are common, and most people will sustain one across a lifetime. There is a typical 3 peak incidence, childhood, young adulthood and in the elderly.
Bone is a relatively brittle material; it maintains sufficient strength to withstand regular day to day activities. Fractures are a result of trauma to bone, when applied force exceeds bone strength. The degree of force typically relates to the outcome, greater force results in greater severity of injury, conversely less severe injuries result from lower applied force. When fractures occur at abnormally low impact they are termed ‘pathological’.
> Open and Closed
> Complete and Incomplete
The mechanism of injury often determines the fracture pattern:
> Sudden trauma
> Repetitive stress
Causes mechanical strain and fatigue, a stress fracture can result, categorised as an incomplete fracture.
See image below for examples of different fracture patterns.
Almost always a good history of the injury (either elicited from the patient, parent or witness) will indicate if a fracture is likely.
It will be common for the patient to report an inability to use the injured limb.
Ensure you take details of the trauma, fall, and landing as relevant.
Think about the mechanism of injury and force distribution, fractures may not always be at the site of impact.
Associated numbness, weakness and bleeding are important- You need to determine if the affected limb is neurovascularly intact.
Enquire about previous injuries.
Don't focus your examination entirely on the suspected fracture.
Examine the person as a whole for any complications and associated injury. Don't overlook ABC.
Always compare limbs- that's why we have two.
MOVE ( ! If appropriate)
NB: When examining for spinal fractures, the patient must be log-rolled and a full peripheral nervous system examination performed.
X-Rays of a suspected fracture are mandatory and usually diagnositic. Medical practioners have a low threshold for requesting x-ray if the history or clincal exam is sugestive of bone injury.
Always remember the rule of two:
Special views of certain injuries are preferred. These include Scaphoid views and Mortis view at the ankle.
Usually required when the fracture is multifragmetory, it allows assessment of the fracture pattern. CT is most useful in planning surgical management of complex fractures and identifying articular involvement.
Not frequent in the diagnosis of fractures, but commonly used for assessing for Avascular Necrosis (AVN) and soft tissue injury.
This imaging identifies areas of new bone formation and is most helpful in diagnosing stress fractures.
Fracture repair can be roughly divided into healing with or without callus formation. Repair with callus will occur where there is a degree of movement at the fracture site, where there is no movement direct repair takes place.
Where there is no movement stimulating callus formation, bone is laid down directly across the fracture site. This occurs where rigid fixation is chosen. Mechanical stability is provided by the implant, and callus is not required as a splint. Oestoclasts begin to degrade bone debris with oestoblasts follow behind laying down new bone.
When a bone is able to withstand normal stresses it is functionally repaired. However remodeling will continue after this point, as will restoration of bone density.
Complete repair of bone can take considerable time. The rate is dependent on the type of bone, type of fracture, health of tissue and patient age. The healing process in children is almost half that of an adult.
Diagnosis is often simple but management options are more complex. Three principles are used when treating fractures: Reduction, Stabilisation, and Rehabilitation.
Due to the force of impact or surrounding muscle groups, the normal alignment of the affected bone may be compromised. If this is the case and the alignment of the bone is not satisfactory, the position of the fragments will need to be altered in order to maximise bone healing in the correct position.
Not all fractures result in misalignment, and in these circumstances reduction will not be indicated. Figure 3 demonstrates some examples of deformities that may need to be reduced.
Soft tissue swelling post injury can cause difficulty in reduction and for this reason there should be no unnecessary delay.
> Closed reduction:
If the degree of displacement is minimal, or in most peadiatric fractures, the option of closed reduction is preferred. This can be with: Repositioning in a regular clinical setting with analgesia or Manipulation Under Anaesthetic (MUA), where the patient is taken to theatre and the fracture is reduced by the surgeon with the assistance of x-ray.
> Open reduction:
Surgical intervention is required if closed reduction fails, or if initially the degree of displacement is significant. Open reduction is usually the first stage to internal fixation (Open Reduction and Internal Fixation ORIF)
The theory behind stabilising the fracture is to hold the bone fragments in a good position for healing, prevent excessive movement that could hamper fracture union (this may require joint immobilsation proximal and/or distally) and reduce pain. There is no hard and fast rule for which fracture should be stabilised by which method. Each fracture is individual and should be managed as such, also taking into account patient factors.
Stabilisation falls into two broad categories, Conservative and Operative. Methods of fracture stabilisation are discussed respectively.
1) Casting, usually with Plaster of Paris (POP). This acts as a splint to maintain the either original or post reduction position.
2) Traction, a calculated force is applied to the long axis of the bone, causing opposing fragments to separate and align in the correct position. This is enabled with specialised equipment using weights to generate the traction force. Traction can be applied in one of two methods: Skin traction where the device is applied superficially, around the skin; or secondly where per cutaneous pins, are directly attached to the the distal bone fragment.
Usually termed Open Reduction and Internal Fixation (ORIF)
1) Krishner Wires, also known as K-Wires. Per cutaneous insertion, across the fracture site to maintain alignment. K wires are only temporary, and can be removed once union is established. Metaphysial fractures, and fractures of short bones (ie metacarpal) are often managed with this type of fixation.
2) Plates and Screws, usually used in conjunction. Plates provide mechanical stability as well as ensuring maintainance of alignment. There is many design of plate, tailored for specific regions and fracture pattern. Screws can also be used independently, across a fracture site.
3) Intramedullary nailing, most commonly used in long bones. A nail is passed along the long axis of the bone, within the cortex, acting as an internal splint.
4) External Fixation, provides stability away from the fracture site, without interruption of soft tissue structures. Per cutaneous screws are applied to the proximal and distal fragments of the bone, and attached to a external frame.
5) Hemi and Total Arthroplasty, partial and total joint replacement. This is not a common management of fracture but can be considered in certain intra-articular circumstances and at the femoral neck where there is a risk of Avascular Necrosis (AVN).
Once the fracture has been stabilised and the healing process is underway, attention is diverted to functional improvement and a return to normality. Early mobilisation is often encouraged, providing stability is not compromised. This aids in avoiding joint stiffness, loss of muscle power and oedema.
Rehabilitation is tailored according to both the injury and patient circumstance. Multidisciplinary input is used in varying degrees, this can including the expertise of Physiotherapists and Occupational Therapists if necessary.
Open fractures are a surgical emergency.
Complications that can potentially result from a fracture are divided into local and general effects, but also according to their onset: Early (within hours), Intermediate (days- weeks), Late (weeks-months).
British Orthopaedic Association www.boa.co.uk
Crash Course: Rheumatology and Orthopaedics; Annabel Coote, Paul Haslam; 2nd edition; Mosby; 2004.
Consise System of Orthopaedics and Fractures; Graham Apley, Louis Solomon; 2nd edition; Butterworth Heinemann; 1994.
Essential Orthopaedics and Trauma; David Dandy, Dennis Edwards; 4th edition; Churchill Livingstone; 1999.
Wheeless' Textbook of Orthopaedics; www.wheelessonline.com
Fastbleep © 2019.