Diagnostic algorithm for a validated displacement grading of pediatric supracondylar fractures
Nicolas Lutz1, Laurent Audigé, Peter Schmittenbecher
1Service de Chirurgie Pediatrique CHUV-HEL, Lausanne, Switzerland.
Insights
A new grading system for pediatric supracondylar fractures demonstrates high reliability and accuracy. This classification aids surgeons in distinguishing stable from unstable injuries in clinical practice and research.
Area of Science:
- Orthopedic surgery
- Pediatric trauma
- Fracture classification
Background:
- Established the first AO comprehensive pediatric long bone fracture classification system.
- Developed and validated a grading system for pediatric supracondylar fracture displacement.
Purpose of the Study:
- To specify and evaluate a grading system for displacement of pediatric supracondylar fractures.
- To assess the reliability and accuracy of the new classification system.
Main Methods:
- An iterative process involving 5 experienced pediatric surgeons (Phase 1) and 26 raters in a multicenter study (Phase 2).
- Evaluated 154 supracondylar fractures using standard radiographs.
- Calculated kappa (κ) coefficients for inter-rater reliability.
Main Results:
- Classified fractures into 4 grades (I-IV) based on displacement.
- Achieved overall κ coefficients of 0.68 (Phase 1) and 0.61 (Phase 2).
- Demonstrated high accuracy in distinguishing complete, unstable fractures (κ=0.84 and 0.83).
Conclusions:
- The new grading system is reliable and accurate for supracondylar fracture displacement.
- The system is suitable for both clinical routine and research applications in pediatric orthopedics.
Background:
The first AO comprehensive pediatric long bone fracture classification system has been established following a structured path of development and validation with experienced pediatric surgeons.
Methods:
A follow-up series of agreement studies was applied to specify and evaluate a grading system for displacement of pediatric supracondylar fractures. An iterative process comprising an international group of 5 experienced pediatric surgeons (Phase 1) followed by a pragmatic multicenter agreement study involving 26 raters (Phase 2) was used. The last evaluations were conducted on a consecutive collection of 154 supracondylar fractures documented by standard anteroposterior and lateral radiographs.
Results:
Fractures were classified according to 1 of 4 grades: I=incomplete fracture with no or minimal displacement; II=Incomplete fracture with continuity of the posterior (extension fracture) or anterior cortex (flexion fracture); III=lack of bone continuity (broken cortex), but still some contact between the fracture planes; IV=complete fracture with no bone continuity (broken cortex), and no contact between the fracture planes. A diagnostic algorithm to support the practical application of the grading system in a clinical setting, as well as an aid using a circle placed over the capitellum was proposed. The overall κ coefficients were 0.68 and 0.61 in the Phase 1 and Phase 2 studies, respectively. In the Phase 1 study, fracture grades I, II, III, and IV were classified with median accuracies of 91%, 82%, 83%, and 99.5%, respectively. Similar median accuracies of 86% (Grade I), 73% (Grade II), 83% (Grade III), and 92% were reported for the Phase 2 study. Reliability was high in distinguishing complete, unstable fractures from stable injuries [ie, κ coefficients of 0.84 (Phase 1) and 0.83 (Phase 2) were calculated]; in Phase 2, surgeons' accuracies in classifying complete fractures were all above 85%.
Conclusions:
With clear and unambiguous definition, this new grading system for supracondylar fracture displacement has proved to be sufficiently reliable and accurate when applied by pediatric surgeons in the framework of clinical routine as well as research.
Level Of Evidence:
Diagnostic study, Level II.
