Integrated risk scoring model for predicting dynamic hip screw treatment outcome of intertrochanteric fracture.

BACKGROUND Dynamic hip screw (DHS) is a common device for treating intertrochanteric fracture (ITF). Various risk factors have been reported to be associated with the operative treatment outcome. However, an integrated risk scoring prediction model is lacking. In this study, we aimed to develop a prediction model for treatment outcome of intertrochanteric fracture. METHODS We analyzed 442 AO/OTA 31-A1 and A2 fractures which were treated with DHS during the period January 2000 to June 2014 in a level I trauma center. Risk factors including age, gender, injured side, lag screw position, AO/OTA classification, tip-apex distance, postoperative lateral wall fracture, reduction patterns were analyzed to determine their influence on treatment outcome. Integrated risk scores of significant predictors were used to construct a prediction model. RESULTS AO/OTA 31-A2 classification, postoperative lateral wall fracture, posteriorly inserted lag screw and varus reduction pattern were significant risk predictors for DHS failure. The failure risk for low- and high-risk groups were significantly different (P<0.001) CONCLUSION: AO/OTA 31-A2 classification, postoperative lateral wall fracture, posteriorly inserted lag screw and varus reduction pattern were significant risk predictors for DHS failure. We developed a model that integrates these factors to predict the treatment outcome, which had excellent prediction accuracy and discriminatory ability. The models may provide useful information for orthopedic doctors to identify patients who need early intervention as well as ITF patients who require more frequent follow-up in the postoperative period.