Intraoperative Fractures in Primary Total Knee Arthroplasty: Incidence and Outcomes From a Matched Analysis

Intraoperative fractures during primary total knee arthroplasty (TKA) are rare, but potentially devastating complications. Given their infrequent occurrence, the true incidence, epidemiology, fixation strategies, and outcomes are not well understood.

Using natural language processing, electronic medical records were queried to identify all intraoperative fractures during primary TKA from 2016 to 2021. These patients were matched 1:6 to patients who did not have intraoperative fractures, using age, sex, and surgical date. The incidence of intraoperative fracture, fracture characteristics, treatment, lengths of stay, discharge disposition, and survivorship were compared.

The incidence of intraoperative fracture during primary TKA was 0.21% (43 of 20,089). Most fractures (n = 31; 72%) occurred in the femur, 11 (26%) occurred in the tibia, and one (2%) occurred in the patella. The majority were treated with screw fixation alone or in conjunction with a stemmed and/or constrained implant. The mean surgical duration was 128 minutes in the fracture cohort and 95 minutes in the control group (P < 0.001). The mean length of stay was 95 versus 50 hours in the fracture and control cohorts, respectively (P < 0.008). Regarding discharge, 32 (74%) patients in the fracture cohort discharged home versus 205 (80%) in the control cohort (P value across all categories: 0.269). Survival free from all-cause reoperation was similar between the two groups (hazard ratio, 0.97). The one-, two-, and five-year survivorship free from all-cause reoperation for the fracture versus control cohorts was as follows: one year (98 versus 98%), two year (95 versus 96%), and five year (93 versus 91%).

At a single, high-volume institution, the incidence of intraoperative fracture during primary TKA was 0.21% over a 5-year period. Despite this, the outcomes were similar compared to a propensity-score-matched cohort, suggesting that prompt identification and management using basic fracture and arthroplasty principles can minimize adverse consequences.

IV, retrospective cohort study.