Nationwide Analysis of Lower Extremity Periprosthetic Fractures

Although the annual incidence of primary total joint arthroplasty is increasing, trends in the annual incidence of periprosthetic fractures have not been established. This study aimed to define the annual incidence of periprosthetic fractures in the United States.

Inpatient admission data for 60,887 surgically treated lower extremity periprosthetic fractures between 2006 and 2015 were obtained from the National Inpatient Sample database. The annual incidence of periprosthetic fractures was defined as the number of new cases per year and presented as a population-adjusted rate per 100,000 US individuals. Univariable methods were used for trend analysis and comparisons between groups.

The national annual incidence of periprosthetic fractures presented as a population-adjusted rate of new cases per year peaked in 2008 (2.72; 95% confidence interval [95% CI], 2.39-3.05), remained stable from 2010 (1.65; 95% CI, 1.45-1.86) through 2013 (1.67; 95% CI, 1.55-1.8) and increased in 2014 (1.99; 95% CI, 1.85-2.13) and 2015 (2.47; 95% CI, 2.31-2.62). The proportion of femoral periprosthetic fractures managed with total knee arthroplasty revision remained stable (P_trend = .97) with an increase in total hip arthroplasty (THA) revision (P_trend < .001) and concurrent decrease in open reduction and internal fixation (ORIF) (P_trend < .001). Revision THA was significantly more costly than revision total knee arthroplasty (P = .004), and both were significantly more costly than ORIF (P < .001 for both).

The annual incidence of periprosthetic fractures remained relatively stable throughout our study period. The proportion of periprosthetic fractures managed with revision THA increased, whereas ORIF decreased. Our findings are encouraging considering the significant burden an increase in periprosthetic fracture incidence would present to the health care system in terms of both expense and patient morbidity.