Is Casting of Displaced Pediatric Distal Forearm Fractures Non-inferior to Reduction in General Anesthesia?

Pediatric distal forearm fractures (DFF) are very common and accounts for 25-30% of all fractures in children.(1,2) Up to half of all pediatric DFF are displaced to an extent where surgery has been the preferred treatment option.(3) However, surgery does come with a cost.

The most common treatment of displaced pediatric DFF has long been closed reduction with or without pin fixation (or in rare cases plate and screw fixation) under general anesthesia, followed by immobilization in a cast.(4) Pin-related complications vary from 4-23%, depending on what is reported as complications,(5-11) and up to 40% has been reported when including re-displacements.(12) The insertion of a metal wire or plate also requires subsequent procedures to remove these implants again.

Numerous small cohort studies and case series have found pin fixation advantageous in achieving anatomic reduction and avoiding re-displacement.(5-11) However, whether anatomic reduction and stabilization is important regarding the patient-reported functional outcome has not been investigated since most studies use only radiographic or objective measures (e.g. range of motion). In addition, children's bones, and in particular the metaphysis and epiphysis, have a unique ability to heal and remodel throughout the growth period until puberty.(13) Almost 20 years ago, Do et al. (14) stated that "the tremendous capacity of distal metaphyseal radius fractures to heal and remodel makes this one of the most rewarding fractures to treat non-operatively. […]". In accordance with Do et al., other studies indicate that displaced DFF fractures in prepubertal children might heal without manipulation, and that most displaced fractures will remodel within a year or two to almost anatomical position with no functional impairment.(14-17) Although most surgeons are aware that children's bones have this remodeling potential, they still find it challenging to deal with the uncertainty of whether the bone will actually remodel to an acceptable position. Furthermore, surgeons might have difficulties with how families will react to the waiting time until the misaligned arm looks normal again.

If non-surgical treatment of displaced pediatric DFF were more common, the costs associated with surgery could be minimized. Unfortunately, there is limited evidence to guide the decision to operate or not. The available studies are typically small, retrospective cohort studies or case series of low quality with no predefined follow-up or outcome measures. To our knowledge, there are no published randomized controlled trials (RCTs) comparing non-surgical treatment with surgical treatment, and no studies report outcomes from the patient's perspective.

The aim of this trial is to investigate the patient-reported functional outcome after non-surgical treatment of displaced DFF in children aged 4-10 years. Our hypothesis is, that casting without manipulation is non-inferior to surgical treatment.

Inclusion criteria

• Children 4-10 years of age with open physes
• Fractures in the distal metaphyseal radius (with or without concomitant ulna fracture), including extraarticular physeal fractures (SH I-II)

• Overriding fractures
• Angulated fractures of 20-40°
• The on-duty surgeon finds reduction under anesthesia with or without fixation indicated

Exclusion criteria

• Open fractures
• Nerve or vascular affection
• All intraarticular fractures including SH III-V
• Ulnar physeal fractures
• Polytrauma
• Concomitant ipsi- or contralateral upper extremity fractures (except distal ulna fracture)
• Pathologic fractures
• The injury is >7 days old
• Other conditions that may affect bone healing