Toddlers Fractures - Cast Versus Removable Boot

A toddler's fracture is a fracture that occurs in the lower leg, oven the shin, of children 9 months to four years of age. It usually happens when a young child twists the leg while running or jumping. It is one of the most common injuries of the leg in this age group. In Canada and the United States there are about 80,000 cases per year that present to emergency departments. The good news is that these fractures are stable injuries and heal exceptionally well, without any reported concerns for problems in the future. Despite this, most children with this fracture are managed in a restrictive full circular cast, often including the entire leg, for three to six weeks. This cast management then also includes about two to three repeat visits to see a bone doctor, where the cast is often changed and new x-rays are taken with each visit. However, none of these things has ever been shown to change the way these young children's fractures heal. Further, casting can cause harm such as skin irritation or poor cast fit which may result in problems that are more distressing than the fracture itself. There are also costs to consider. The needless excess costs of the current management strategy in Canada alone can be estimated to be about 1.8 million dollars annually. And so, increasingly, some doctors are choosing to manage these stable fractures with a supportive device on the lower leg, a removable walking boot. This type of device can be taken off as needed by the parent and child and used only as long as the child needs it to manage the pain that results from this stable fracture. This makes caring for the child much easier and allows the child to return to activities when the child is ready. Further, families do not necessarily need to return to a bone doctor for cast changes or x-rays or reassessment. Since this fracture recovers so well, patients can see their family doctor to make sure their child is returning to activity as expected and have their questions about recovery answered. But, in order to be sure that the removable walking boot works as well as a cast in these fractures, we need to do a well-designed study to make sure we consider all the important aspects of making this change. As a result, in children with toddler's fractures, we will compare the traditional treatment of cast placement to a removable walking boot with respect to how each immobilization strategy controls pain and how quickly children return to their usual activities. We hope that children treated with a removable walking boot will still be able to achieve good pain control while their injury is healing. It is possible too those children will even return to their activities sooner and this newer strategy could save the health care system money.

Background:

Toddler's fractures (TF) are characterized as stable, spiral or oblique fractures of the tibial diaphysis or distal metaphysis that mainly occur in children between nine months and four years of age. Despite its inherent stability, the most frequent treatment option remains an above/below knee casting for three to six weeks, without clear and strong evidence to do so. Casting and orthopedic follow-up results in further burden including unnecessary visits to an orthopedic surgeon, additional sets of lower extremity radiographs and day-to-day inconveniences/complications (e.g. bathing/showering, problems of fit, breakage, and skin related complications). Commercially available removable immobilization devices have been applied successfully to low-risk stable extremity pediatric fractures, and have numerous advantages over conventional immobilization with casts (e.g. easy care, comfort and application/removal convenience) but have not properly been studied in the management of TF.

Study Aims:

To compare the recovery of children with TF when treated with a commercial, removable immobilization device versus an above-knee walking fiberglass cast.

Hypothesis:

The removable pediatric walking boot will be at least as effective as the walking above-knee cast with respect to pain with ambulation as measured by the EVENDOL scale at four weeks after injury.

Research Design:

This is a multi-centre, two-arm, non-inferiority randomized control trial. All independently weight-bearing children age 9 months to 4 years who present to the ED within five days of a lower extremity injury/complaint and diagnosed clinically and radiolographically with an accidental TF will be eligible for enrolment. Study participants will be randomly assigned to receive either a removable below knee device or a circumferential walking cast. The main outcome will be pain with ambulation as measured by the EVENDOL pain scale at four weeks. Complications, day-to-day burdens, unscheduled visits will be ascertained, as the impact and satisfaction with the treatment device. Accounting to a maximal 20% drop-off rate, a sample size of 160 participants was calculated to have a power of 90% to identify a difference of 2 with an alpha value of 0.025. About one-third of participants will be recruited at CHU Sainte-Justine (n=54).

Relevance:

Current practice patterns predominately include treatment with a circumferential cast for several weeks. This type of rigid immobilization is likely unnecessary for such a stable injury. However, the research to date comparing casting with removable devices in children with TF has significant limitations and has not been of sufficient quality to change the immobilization and follow-up practice of TF. Specifically, retrospective design and analyses of data collected for a different purpose is subject to methodological limitations such as bias, missing data, and inconsistent measurement of outcomes. Further, these data have typically been limited to a single site, limiting generalizability. Other research has gathered data using surveys, which is limited by the fact that what physicians say they do does not necessarily represent what they actually do, and hence does not necessarily accurately represent clinical practice or outcomes. Finally, no research to date has considered the perspectives of families who need to care for these injured toddlers at home. Therefore, to secure the confidence of all relevant stakeholders, we need to provide high quality evidence to determine the most effective and convenient management strategy for this common childhood injury. If we can demonstrate that a removable device is at least as safe and effective as a circumferential cast in the treatment of TF, there are likely to be similar benefits for these fractures as it has been found with other minor pediatric fractures (e.g. comfort/convenience, safety, recovery, and cost-effectiveness advantages). As this is a common injury in childhood, the use of a removable device to manage this injury is highly likely to result in lower morbidity and save costs for the health care system and population, and these advantages will also generalize nationally and internationally.

Eligibility Criteria:
Inclusion Criteria:

* Otherwise healthy, independently weight-bearing children aged 9 months to 4 years
* Present to the ED at SickKids, LHSC or CHU Sainte-Justine within five days of a lower extremity injury
* Diagnosed clinically and radiographically with an accidental TF will be eligible for enrolment

Exclusion Criteria:

* Children at risk for pathological fractures (Appendix 1) or those with chronic conditions (arthritis or neuromuscular disorders) since these children have different management requirements and potentially different pain and recovery timelines
* Children with multi-limb injuries
* Children with neuromotor deficits such that assessment of recovery or pain is confounded by the deficits
* Children whose parents/guardians who are unable to provide consent or complete follow-up procedures due to an insurmountable language barrier, or no access to a phone or electronic mail
* Children with diagnostic uncertainty of a TF (e.g. occult TF) or those whose TF might be the result of non-accidental injury