Periarticular Hardware Retention does not Increase Reoperation Risk in Conversion Total Knee Arthroplasty

Total knee arthroplasty (TKA) in the setting of retained periarticular hardware presents technical challenges and may influence surgical complexity and outcomes. This study aimed to evaluate whether hardware retention at the time of conversion TKA impacts reoperation risk, perioperative outcomes, and patient-reported outcome measures.

A retrospective cohort study was conducted of 320 patients who underwent conversion or primary TKA between 2009 and 2019. Patients were categorized into three groups: no retained hardware (n = 171), retained "minor" hardware (n = 90), and retained "major" hardware (n = 59), based on intraoperative complexity. The primary outcome was risk of reoperation and was assessed using a risk-adjusted Fine-Gray subdistribution hazard model that adjusted for death as a competing event. The secondary outcomes included operative time, blood loss, lengths of stay, complications, and patient-reported outcome measures (University of California, Los Angeles (UCLA) Activity Score, Veterans RAND 12-Item (VR-12) Health Survey Physical and Mental Component Scores) were assessed using univariate tests.

There were no significant differences in the risk of reoperation among the three groups (multivariable Fine-Gray analysis: P = 0.162). Operative time and blood loss were significantly higher in the major hardware group (P < 0.001). Lengths of stay and complication rates also varied across groups (P < 0.05). The PROMs at one and two years showed minor differences, with lower improvements in VR-12 Mental Scores and UCLA scores in the major hardware group at one year (P = 0.034 and P = 0.016, respectively).

While periarticular hardware retention in conversion TKA was associated with increased operative time, blood loss, and early complications, especially with plates or intramedullary nails, it was not associated with higher reoperation rates or two-year patient-reported outcomes.