Preoperative Platelet and International Normalized Ratio Thresholds and Their Impact on Complications Following Revision Total Joint Arthroplasty

Background Traditional thresholds of platelet counts ≥50,000/μL and international normalized ratio (INR) < 1.5 may not adequately capture the risks of mild coagulopathy. This study evaluated complication rates across varying preoperative platelet and INR values in patients undergoing revision total joint arthroplasty. Methods Patients undergoing revision total knee or hip arthroplasties were retrospectively identified from a health care database. Patients were stratified by preoperative platelet counts (50,000 to 100,000/μL, 100,000 to 150,000/μL, >150,000/μL) and INR (<1.0, 1.1 to 1.5, 1.6 to 2.0, >2.0) recorded within 30 days of surgery. Following 1:1 propensity score matching to adjust for confounders, evaluated outcomes included transfusions, bleeding, thromboembolic events, wound complications, periprosthetic joint infection (PJI), reoperation, and mortality up to 2 years. Results Platelet counts of 50,000 to 100,000/μL were associated with increased transfusions, greater 90-day bleeding, and higher 2-year PJI and mortality. Counts of 100,000 to 150,000/μL were similarly linked to higher transfusions, PJI, and mortality. An INR of 1.1 to 1.5 correlated with increased 90-day transfusions, wound complications, and thromboembolic events, alongside higher 2-year PJI, reoperation, and mortality. INR levels >1.5 were consistently associated with elevated 90-day thromboembolic events and increased 2-year PJI, with levels of 1.6 to 2.0 also linked to higher mortality. Conclusions The findings from this study indicate that preoperative platelet counts below 150,000/μL and INR values above 1.0 were associated with higher rates of complications following revision total joint arthroplasty. These results suggest stricter optimization of hematologic parameters preoperatively may reduce complications.