Acceptable Reduction Parameters for Pediatric Radius Fractures
For children under 9 years of age, accept up to 15° of angulation and complete displacement; for children 9 years and older, accept up to 15° of angulation for distal fractures and 10° for proximal fractures, with up to 30° of malrotation. 1
Age-Stratified Angulation Limits
Children < 9 Years Old
- Angulation: Up to 15° is acceptable at any level of the radius 1
- Displacement: Complete bayonet apposition is acceptable, particularly for distal radius fractures, provided angulation does not exceed 20° and at least 2 years of growth remain 1
- Malrotation: Up to 45° is acceptable 1
Children ≥ 9 Years Old
- Distal radius fractures: Up to 15° of angulation is acceptable 1
- Proximal radius fractures: Up to 10° of angulation is acceptable 1
- Malrotation: Up to 30° is acceptable 1
- Displacement: Complete bayonet apposition remains acceptable if angulation stays within limits and growth potential exists 1
Fracture Location-Specific Considerations
Distal Radius Fractures
- Greater remodeling potential allows more liberal acceptance of displacement in younger children 1
- Distal radius fractures demonstrate the highest rate of loss of reduction at 44%, compared to 17% for mid-shaft and 14% for proximal fractures 2
- Bicortical metaphyseal fracture patterns increase odds of loss of reduction by 2.3-fold 3
Mid-Shaft and Proximal Fractures
- Stricter angulation limits apply, particularly in older children 1
- Mid-shaft and proximal fractures maintain reduction better with sugar-tong splinting (17% and 14% loss of reduction rates respectively) 2
Critical Risk Factors for Loss of Reduction
High-Risk Fracture Characteristics
- Pre-reduction translation ≥51% of radial shaft width increases loss of reduction odds by 2.3-fold 3
- Bicortical metaphyseal pattern increases loss of reduction odds by 2.3-fold 3
- Non-anatomic closed reduction increases loss of reduction odds by 1.9-fold 3
- Concomitant ulna fracture increases loss of reduction odds by 1.71-fold 4
- Initial radius displacement >75% increases loss of reduction odds by 5.4-fold 4
Timing of Redisplacement
- 80-90% of all loss of reduction occurs within the first 2 weeks after closed reduction 2, 4
- Radiographs at 1 and 2 weeks post-reduction are critical for detecting early angulation 1, 4
- The 4-week radiograph adds minimal clinical value, as no statistically significant alignment changes occur after week 2 4
Translation Tolerance
Any residual translation at the time of closed reduction significantly increases redisplacement risk 3
- Dedicated effort should minimize fracture translation at primary closed reduction—not because of remodeling concerns, but to prevent angulation-driven loss of reduction 3
- Pre-reduction translation ≥51% is an independent predictor of failure 3
Common Pitfalls to Avoid
Reduction Technique Errors
- Greenstick fractures: Reduce by rotating the forearm so the palm is directed toward the fracture apex 1
- Complete fractures: Manipulate with traction and rotation, then immobilize in well-molded plaster casts 1
- Failure to achieve anatomic reduction at initial closed reduction increases loss of reduction risk 3
Follow-Up Imaging Errors
- Obtain radiographs between 1-2 weeks after initial reduction to detect early angulation 1
- Do not rely solely on 4-week radiographs, as 100% of interventions are based on findings within the first 2 weeks 4
- The rate of radiographic loss of reduction is 44% overall, with 11% shifting ≥20° 3
Age-Related Miscalculations
- Patient age, sex, and BMI are not significant predictors of loss of reduction 3
- The key determinants are fracture characteristics and quality of initial reduction, not patient demographics 3