By: 17 April 2019
BOAST Guidelines for management of ankle fractures

The British Orthopaedic Association Standards for Trauma (BOASTs) sets out guidelines for best practice of specific injuries. The guidelines for management of ankle fractures were introduced in August 2016. Similar to the guidelines for distal radius fractures we looked at last year, Sam Anand now looks at management of ankle fractures, as it is once again a common injury which is encountered in daily practice

The inclusion criteria are all closed fractures and syndesmotic ankle injuries in skeletally mature patients and these guidelines exclude all pilon fractures, open ankle fractures and ankle fractures in skeletally immature patients.

The mechanism of injury and clinical findings, including skin integrity, assessment of circulation and sensation, should be precisely documented at presentation.
This is hopefully standard practice at most A&E departments. For purposes of looking at the guidelines we will assume this to be an isolated injury. Documentation of distal neuro vascular status is of critical importance.

Co-morbidities that might influence treatment choice and outcome should be documented. These might include pre-existing mobility impairment, diabetes mellitus, peripheral neuropathy, peripheral vascular disease, osteoporosis, renal disease, smoking and alcohol abuse.
These are part of a good history and should be well documented, including medication history and also a note made of when the patient last ate or drank. This is important if surgical management is deemed necessary.

Reduction and splinting should be performed urgently for clinically deformed ankles. Radiographs should be obtained before reduction unless this will cause an unacceptable delay.
All displaced fractures especially with the ankle joint subluxed or frankly dislocated should be reduced asap. If getting radiographs is going to delay this it is better to reduce the deformity to a neutral position to take pressure of the soft tissues.

Radiographs should be centred on the ankle and should include a true lateral and mortise view.
This would be standard practice in most units. Additional Xrays, such as of the knee or higher of the fibula are done when syndesmotic injuries are suspected.

Additional radiographs of the whole leg are required when clinical examination suggests a more proximal fracture of the fibula (Maisonneuve injury). Separate radiographs of the foot and knee should be obatained if clinically indicated. CT imaging may be helpful in defining fracture configuration in more complex patterns particularly where the posterior malleolus is involved.
Additional imaging is purely based on the individual fracture pattern and should be only done on a case-by- case basis.

Following reduction, neurovascular examination must be repeated and documented.
As mentioned before, neuro vascular status examination and documentation is critical and should be repeated after any intervention.

Adequate reduction must be confirmed by review of repeat radiographs and documented before transfer from ED.
This is important even in undisplaced fractures, as with inherently unstable fracture patterns there is a small chance that fractures can displace following application of any form of splinting.

Fractures considered stable should be treated with analgesia, splinting and patients allowed to weight bear as tolerated. Further follow up may not be necessary.
This is for very distal undisplaced fibular fractures below the level of the ankle mortise. If the patient is seen in a next day fracture clinic by the trauma team and the injury confirmed as indeed stable, further follow up may not be necessary.

In fracture patterns where stability is uncertain, patients should be reviewed within two weeks with further radiographs (weight bearing if possible) to confirm the position remains acceptable.
If the radiographs at two weeks show further displacement in comparison to the original position a decision can be made for further intervention as necessary.

Early fixation (on the day or day after) is recommended in the majority of patients under 60 years when the ankle mortis is unstable. The use of external fixation is rarely indicated in the presence of gross instability associated with soft tissue compromise.
There should be a big push for early surgical intervention with internal fixation and ideally these fractures are best surgically fixed within six hours of presentation if possible. If this is not possible and gross instability persists with soft tissue compromise, external fixation will be necessary.

In patients over 60 years, close contact casts are an option if reduction can be maintained.
This is an acceptable method of management in the elderly with co-morbidities or other contra indications to surgery, for example poor quality of overlying soft tissues. However, if this is the treatment option pursued regular follow-up at weekly intervals, especially in the first few weeks, is necessary with radiographs to make sure there is no displacement of the fractures.

Surgery should aim to achieve anatomic reduction and stabilisation of the ankle mortise. The syndesmosis should then be assessed and stabilised if unstable. Intra-operative radiographs should be obtained to confirm reduction.
As with any fracture fixation surgery especially with peri-articular fractures anatomical reduction is essential. If there is any doubts about the syndesmosis there should be a low threshold for stabilising the syndesmosis

Most patients should be allowed to weight bear as tolerated in a splint or cast unless there are specific concerns regarding the stability of the fixation or contra indications, such as peripheral neuropathy or particular concerns about the status of the soft tissues.
As long as anatomical reduction is achieved of the ankle mortise and fixation is stable, early weight-bearing as tolerated should be encouraged.

After surgery, patients should be followed up in fracture clinic within six weeks of surgery to detect complications and confirm maintenance of reduction on radiographs.
Following surgical fixation of fractures, ideally a two-week check to look at soft tissues and a six-week check with radiographs should be aimed for.

Thromboprophylaxis risk assessment should follow agreed local protocols.
All ankle fractures are significant lower limb injuries and all these patients are at a higher risk of developing deep vein thombosis and there should be a low threshold to start patients on some form of thromboprophylaxis according to local protocol.

All patients should receive information regarding expected functional recovery and rehabilitation including advice about return to normal activities such as work and driving. A mechanism should be in place for patients to self-refer to the fracture service if progress is not as anticipated.
Detailed information regarding the injury should be available to the patients, preferably in a written format. Ideally, patients should not be discharged from the fracture service till full clinical evidence of recovery. Routine removal of any metal ware used for surgical fixation is not necessary unless it is symptomatic.

Ankle fractures are common injuries which are encountered every day in A&E departments and fracture clinics. The above guidelines give us a good framework to stick to in the management of this not so uncommon injury. This will be a good audit tool for A&E and trauma departments to implement quality improvement projects.