Radiograph-Negative Lateral Ankle Injuries in Children

Abstract

IMPORTANCE Lateral ankle injuries without radiographic evidence of a fracture are a common pediatric injury. These children are often presumed to have a Salter-Harris type I fracture of the distal fibula (SH1DF) and managed with immobilization and orthopedic follow-up. However, previous small studies suggest that these injuries may represent ankle sprains rather than growth plate fractures. OBJECTIVES To determine the frequency of SH1DF using magnetic resonance imaging (MRI) and compare the functional recovery of children with fractures identified by MRI vs those with isolated ligament injuries. DESIGN, SETTING, AND PARTICIPANTS A prospective cohort study was conducted between September 2012 and August 2014 at 2 tertiary care pediatric emergency departments. We screened 271 skeletally immature children aged 5 to 12 years with a clinically suspected SH1DF; 170 were eligible and 140 consented to participate. INTERVENTIONS Children underwent MRI of both ankles within 1 week of injury. Children were managed with a removable brace and allowed to return to activities as tolerated. MAIN OUTCOMES AND MEASURES The proportion with MRI-confirmed SH1DF. A secondary outcome included the Activity Scale for Kids score at 1 month. RESULTS Of the 135 children who underwent ankle MRI, 4 (3.0%; 95% CI, 0.1%-5.9%) demonstrated MRI-confirmed SH1DF, and 2 of these were partial growth plate injuries. Also, 108 children (80.0%) had ligament injuries and 27 (22.0%) had isolated bone contusions. Of the 108 ligament injuries, 73 (67.6%) were intermediate to high-grade injuries, 38 of which were associated with radiographically occult fibular avulsion fractures. At 1 month, the mean (SD) Activity Scale for Kids score of children with MRI-detected fibular fractures (82.0% [17.2%]) was not significantly different from those without fractures (85.8% [12.5%]) (mean difference, −3.8%; 95% CI, −1.7% to 9.2%). CONCLUSIONS AND RELEVANCE Salter-Harris I fractures of the distal fibula are rare in children with radiograph fracture-negative lateral ankle injuries. These children most commonly have ligament injuries (sprains), sometimes associated with radiographically occult avulsion fractures. Children with fractures detectable only by MRI had a comparable recovery with those with sprains when treated with a removable ankle brace and self-regulated return to activities. This work has the potential to simplify the care of these common injuries, safely minimizing the inconveniences and costs of overtreatment.

Nationwide survey on current management strategies of toddler’s fractures

“…In the case of distal radial buckle fractures and suspected Salter-Harris 1 fractures of the distal fibula, randomized controlled trials have shown that healing occurs without casting with low complication rates. [13][14][15][16][17][18][19][20][21] In addition, family satisfaction was significantly higher in those groups managed without casting or with the most minimally invasive strategy. 18 Similar to the above-mentioned injuries, TFs are non-displaced fractures, have intact bony cortices, and do not involve the proximal or distal tibial growth plates.…”

“…Although accessibility, cost-effectiveness, and radiation exposure may be limiting factors, magnetic resonance imaging, bone scintigraphy, and computed tomography have been shown to improve the diagnostic accuracy of children with other occult fractures. 16,22 There is a paucity of literature regarding the diagnostic gold standard to rule in or rule out presumed TF. In the era of point-ofcare testing, ultrasonography may prove to be helpful in bridging this diagnostic gap.…”

Adverse Events from Emergency Physician Pediatric Extremity Radiograph Interpretations: A Prospective Cohort Study

“…A severe injury included those that required an urgent orthopedic intervention (e.g., fracture reduction, operation) and/or hospitalization . At the study institution, distal radius buckle fractures and nondisplaced distal fibular Salter‐Harris I or II and avulsion fractures are treated with a removable splint and follow‐up with the primary care physician and thus were classified as “mild injuries.” At the study institution, orthopedics/plastics is consulted for any patient that may require an emergent fracture reduction or stabilization. For those stable injuries that do not require an emergent or urgent procedure or those postprocedure that are dischargeable, it is routine practice to refer moderate to severe injuries to the orthopedic or plastics hand clinic, and patients are seen within 1 week of the index ED visit.…”

Ankle and Foot Injuries in the Young Athlete

“…Children with lateral ankle injuries and no radiographic abnormality are presumed to have a SH type I fracture of the distal fibula and are managed with immobilization and orthopaedic follow-up. A prospective study by Boutis et al 58 of 135 children demonstrated that only 3% of patients with normal ankle radiographs after lateral ankle injury had a distal fibular SH type I fracture, and most patients had ligamentous injuries followed by bone contusions. Almost 30% of patients with ligamentous injuries also had radiographically occult fibular avulsion fractures.…”