OBJECTIVES

: This study evaluated the rates of breakage of intramedullary nailing (IMN) and factors associated with breakage over two years following IMN for trochanteric, intertrochanteric and subtrochanteric femur fractures.

METHODS

: This retrospective observational cohort analysis used the IBM® Marketscan® Medicare Supplemental database between 2010 and 2017. All patients 65 years or older with a claim for IMN procedure for femur fractures (trochanteric, intertrochanteric and subtrochanteric) in an inpatient setting were included. The date of IMN procedure was defined as the index date. Rates of breakage for trochanteric, intertrochanteric subtrochanteric or combinations of these femoral fractures were reported at two-years post-index hospital discharge. Multivariable logistic regression was conducted to identify the factors that predict the risk for breakage over two years period.

RESULTS

: A total of 36,544 patients with intramedullary nailing for trochanteric, intertrochanteric, subtrochanteric or combinations of these femoral fractures were identified. The mean (standard deviation, SD) age for the cohort was 83.7 (7.6) years and most patients were female (72.4%). The mean (SD) length of stay for the IMN procedure was 6.7 (4.2) days. Crude rates of breakage at the 2-year time point were 0.10% for intertrochanteric only, 0.16% for subtrochanteric only, 1.2% for trochanteric only and 0.33% for sub- and intertrochanteric. The overall rate of breakage was 0.12%. Results from the logistic regression analysis showed that increased age (odds ratio [OR], 2.63), female sex (OR, 1.53), higher Elixhauser score (OR, 2.52), osteoporosis (OR, 10.30) and rheumatoid arthritis (OR, 2.39) were statistically significantly associated with breakage of IMN (All p<0.05).

CONCLUSIONS

: Femoral fractures treated by IMN had an overall breakage rate of 0.12% within 2 years after implant. In this study population, the results indicate treatment of femoral fractures with IMN is associated with low rates of breakage two years after implant.