Waterproof Casting for Pediatric Distal Radius Fractures

Distal radius fractures are one of the most commonly seen fractures in children.
Traditionally, minimally angulated or non-displaced distal radius fractures are treated with
short or long-arm cast immobilization for up to 8 weeks. The traditional fiberglass casts
used must be kept dry to prevent inflammation and potential infection. If a fiberglass cast
gets wet, it must be removed and replaced. In general, waterproof casting has been shown to
improve patient comfort and overall satisfaction.

We intend to explore the efficacy of a new, waterproof cast made of a hybrid mesh in the
treatment of minimally angulated distal radius fractures in children using a randomized,
controlled, cross-over study design. We will include patients between 4 and 14 years of age
with minimally angulated distal radius fractures (<15 degrees of angulation on sagittal or
coronal planes) presented to the Orthopaedic Institute for Children Urgent Care Facility
within 7 days of injury. As determined by a power analysis, a total of 26 patients will be
enrolled in the study.

Patients eligible for the study will be randomized into one of two equally sized (n=13)
groups: patients in Group 1 will receive a short arm cast made of the waterproof hybrid mesh
material and patients in Group 2 will receive a regular fiberglass cast. Both groups will
follow-up at two weeks for clinical and radiological evaluation, after which they will be
transitioned into a regular fiberglass cast (Group 1) or a hybrid mesh waterproof cast (Group
2) for an additional two weeks. This crossover will allow both groups to experience each type
of cast. After four weeks of immobilization, patients in both groups will discontinue casting
and be advised to avoid contact sports or strenuous activities until week 8.

Patients in both groups will follow up 8 weeks after initial treatment for clinical and
radiological evaluation to evaluate range of motion, pain, and fracture alignment. Physical
function will be evaluated at weeks 1, 2, and 4 using the Activities Scale for Kids -
Performance, a validated, highly reliable, self-reported measure that assesses physical
function in children between 5 and 15 years. Pain will be evaluated using the Faces Pain
Scale, a validated, highly reliable scale commonly used in the pediatric population. Patient
satisfaction will be measured at Weeks 1, 2, and 4, and the radiographs at Week 8 will be
compared with initial radiographs to assess fracture displacement and angulation. Skin
changes will be assessed at week 2 and week 4 by an independent observer blinded to the type
of cast that has been removed and digital photographs will be obtained and analyzed using
ImageJ Image Processing and Analysis Software to calculate the surface area of any described
skin changes as a percentage of total skin area originally covered by the cast. Itching will
be assessed at weeks 1, 2, and 4 using a visual analogue scale in which a horizontal line of
100 mm will be presented to the patient with "no itching" at the left end of the scale and
"strongest itching" at the right end.

We hope to determine whether the new, waterproof cast can result in similar clinical outcomes
and patient satisfaction for distal radius fractures as compared with the traditional
fiberglass cast.