A broken ankle, also called an ankle fracture, involves a break in one or more of the three bones that make up the ankle. It often results from a twisted ankle. Ankle fracture is a common injury in children. Some fractures are minor, and the bones remain in place. Other fractures are more serious, such as when the broken bones are displaced from each other or even come through the skin. These fractures can affect the way the bones grow. Serious disruption of the growth plates may result in leg deformity.
Minor fractures are often treated by placing the injured leg in a removable fibreglass splint or a plaster cast. These devices may also be used for some displaced fractures after the displaced fracture parts have been put back into place. However, displaced fractures often require surgery. An operation enables the surgeon to put the broken bone pieces back into their correct places. Screws, plates and pins are typically used to hold the bones in place. The leg is usually placed in a plaster cast while the bones heal.
Results of the search
We searched medical databases up to September 2015 and included three randomised studies reporting results for 189 children. All the children were considered by the treating clinicians to have minor ankle fractures that were at low risk of growth-plate complications.
Two studies compared the use of a removable prefabricated ankle brace with a rigid cast. One study used a removable fibreglass splint for two weeks, and the other used a below-the-knee plaster walking cast for three weeks. Both studies provided some evidence of a quicker recovery of self reported function at four weeks in children who were treated with an ankle brace compared with those treated with a rigid cast. One study reported more complications, such as pressure marks and blisters, in the brace group. Most of these were attributed to a protective sock not being worn with the brace. The other study reported more unscheduled visits to healthcare providers for problems in the rigid-cast group. In this study, children much preferred the brace, which could be removed after five days, than the cast, which remained on for three weeks. Neither study reported results in the long term.
The third study compared the Tubigrip bandage plus crutches and advice versus a plaster of Paris walking cast for two weeks. This study found some weak evidence of an earlier return to former activities of around six days (14 compared with 20 days) in children in the Tubigrip group. The study did not report on complications or long-term outcome.
Quality of the evidence
All three studies had weaknesses that could have affected the reliability of their results. We considered the evidence to be generally of low or very low quality, which means we are unsure of these results.
Using an ankle brace rather than a rigid cast, in particular a non-removable walking cast, may result in quicker recovery in children with minor ankle fractures. Further studies are required to identify the best treatment for broken ankles in children.
There is low-quality evidence of a quicker recovery of self reported function at four weeks in children with clinically diagnosed low-risk ankle fractures who are treated with an ankle brace compared with those treated with a rigid cast, especially a non-removable walking cast. There is otherwise a lack of evidence from randomised controlled trials to inform clinical practice for children with ankle fractures. Research to identify and address priority questions on the treatment of these common fractures is needed.
Ankle fractures, which usually occur after a twisting incident, are a diverse collection of injuries with different levels of complexity and severity. They have an incidence of 1 in 1000 a year in children. Treatment generally involves splints and casts for minor fractures and surgical fixation with screws, plates and pins followed by immobilisation for more serious fractures.
To assess the effects (benefits and harms) of different interventions for treating ankle fractures in children.
We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (22 September 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 8), MEDLINE (1946 to September Week 2 2015), MEDLINE In-Process & Other Non-Indexed Citations (21 September 2015), EMBASE (1980 to 2015 Week 38), CINAHL (1937 to 22 September 2015), trial registers (17 February 2015), conference proceedings and reference lists of articles.
We included randomised and quasi-randomised controlled trials evaluating interventions for treating ankle fractures in children.
Two review authors independently screened titles, abstracts and full articles for inclusion, assessed risk of bias and collected data. We undertook no meta-analysis.
We included three randomised controlled trials reporting results for 189 children, all of whom had a clinical diagnosis of a "low risk" ankle fracture. These were predominantly classified as undisplaced Salter-Harris type I fractures of the distal fibula. All three trials compared non-surgical management options. The three trials were at high risk of bias, primarily relating to the impracticality of blinding participants and treating clinicians to the allocated interventions.
Two trials compared the Aircast Air-Stirrup ankle brace versus a rigid cast, which was a removable fibreglass posterior splint in one trial (trial A) and a below-knee fibreglass walking cast in the other trial (trial B). In trial A, both devices were removed at around two weeks. In trial B, removal of the brace was optional after five days, while the walking cast was removed after three weeks. There was low-quality evidence of clinically important differences in function scores at four weeks in favour of the brace groups of both trials. Function was measured using the Activities Scale for Kids-performance (ASKp; score range 0 to 100, higher scores mean better function) in trial A and using a modified version of the ASKp score (range 0 to 100%, higher percentages mean better function) in trial B. The results for trial A (40 participants) were median 91.9 in the brace group versus 84.2 in the splint group. The results for trial B (104 participants) were 91.3% versus 85.3%; mean difference (MD) 6.00% favouring brace (95% confidence interval (CI) 1.38% to 10.62%). Trial B indicated that 5% amounted to a clinically relevant difference in the modified ASKp score. Neither trial reported on unacceptable anatomy or related outcomes or long-term follow-up. There was very low-quality evidence relating to adverse events, none of which were serious. Trial A found twice as many children with pressure-related complications in the brace group (10 of 20 versus 5 of 20). In contrast, trial B found four times as many children in the cast group had adverse outcomes assessed in terms of an unscheduled visit to a healthcare provider (4 of 54 versus 16 of 50). Both trials linked some of the adverse events in the brace group with the failure to wear a protective sock. There was very low-quality evidence indicating an earlier return to pre-injury activity in the brace groups in both trials. Trial B provided low-quality evidence that children much prefer five days or more wearing an ankle brace than three weeks immobilised in a walking ankle cast. There was moderate-quality evidence of a lack of difference between the two groups in pain at four weeks.
The third trial compared the Tubigrip bandage plus crutches and advice versus a plaster of Paris walking cast for two weeks and reported results at four weeks' follow-up for 45 children with an inversion injury of the ankle. The trial found very low-quality evidence of little difference in pain and function between the two groups, measured using a non-validated pain and function score at four weeks. The trial did not report on adverse effects. There was very low-quality evidence of an earlier return to normal activities, averaging six days, in children treated with Tubigrip (mean 14.17 days for Tubigrip versus 20.19 days for cast; MD -6.02 days, 95% CI -8.92 to -3.12 days).
Recent evidence from magnetic resonance imaging studies of the main category of injury evaluated in these three trials suggests that most of the injuries in these trials were sprains or bone bruises rather than fractures of the distal fibular growth plate.