Are distal radius fracture classifications reproducible? Intra and interobserver agreement.
OBJECTIVE
Various classification systems have been proposed for fractures of the distal radius, but the reliability of these classifications is seldom addressed. For a fracture classification to be useful, it must provide prognostic significance, interobserver reliability and intraobserver reproducibility. The aim here was to evaluate the intraobserver and interobserver agreement of distal radius fracture classifications.


METHODS
This was a validation study on interobserver and intraobserver reliability. It was developed in the Department of Orthopedics and Traumatology, Universidade Federal de São Paulo - Escola Paulista de Medicina.


METHODS
X-rays from 98 cases of displaced distal radius fracture were evaluated by five observers: one third-year orthopedic resident (R3), one sixth-year undergraduate medical student (UG6), one radiologist physician (XRP), one orthopedic trauma specialist (OT) and one orthopedic hand surgery specialist (OHS). The radiographs were classified on three different occasions (times T1, T2 and T3) using the Universal (Cooney), Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF), Frykman and Fernández classifications. The kappa coefficient (kappa) was applied to assess the degree of agreement.


RESULTS
Among the three occasions, the highest mean intraobserver k was observed in the Universal classification (0.61), followed by Fernández (0.59), Frykman (0.55) and AO/ASIF (0.49). The interobserver agreement was unsatisfactory in all classifications. The Fernández classification showed the best agreement (0.44) and the worst was the Frykman classification (0.26).


CONCLUSIONS
The low agreement levels observed in this study suggest that there is still no classification method with high reproducibility.
Belloti
João Carlos
JC
Department of Orthopedics and Traumatology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil. jbelloti@terra.com.br
Tamaoki
Marcel Jun Sugawara
MJ
Franciozi
Carlos Eduardo da Silveira
CE
Santos
João Baptista Gomes dos
JB
Balbachevsky
Daniel
D
Chap Chap
Eduardo
E
Albertoni
Walter Manna
WM
Faloppa
Flávio
F
D000328:Adult; D003100:Colles' Fracture / Q000145:classification / Q000000981:diagnostic imaging; D006801:Humans; D015588:Observer Variation; D011379:Prognosis; D011859:Radiography; D011885:Radius Fractures / Q000145:classification* / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity