The comparison of two classifications for trochanteric femur fractures: the AO/ASIF classification and the Jensen classification.

This study compares the reproducibility of two classifications for trochanteric femur fractures: the Jensen classification and the AO/ASIF classification. Furthermore we evaluated the agreement on fracture stability, choice of osteosynthesis, fracture reduction and the accuracy of implant positioning. In order to calculate the inter-, and intra-observer variability 10 observers classified 50 trochanteric fractures. The inter-observer agreement of the AO/ASIF classification and the Jensen classification was kappa0.40 and kappa0.48. The kappa coefficient of the intra-observer reliability of the AO/ASIF classification was kappa0.43 and kappa0.56 for the Jensen classification. Preoperative agreement on fracture stability and type of implant showed kappa values of kappa0.39 and kappa0.65. The postoperative agreement on choice of implant, fracture reduction and position of the implant was kappa0.17, kappa0.29 and kappa0.22, respectively. Both classifications showed poor reproducibility. This study suggests that the definition of stability of trochanteric fractures remains controversial, which possibly complicates the choice of osteosynthesis.