Patient-Specific Instrumentation Affects Perioperative Blood Loss in Total Knee Arthroplasty

Abstract Patient-specific instrumentation (PSI) may contribute to reduced blood loss related to total knee arthroplasty (TKA). The purpose of this study was to compare the estimated hemoglobin (Hb) and red blood cell volume (RBC) losses in two groups of patients undergoing TKA with PSI and conventional instrumentation. Pre- and postoperative blood samples were collected from 22 patients randomly assigned to receive a PSI-assisted or conventional TKA. Post- to preoperative Hb difference was calculated and RBC loss was estimated according to Sehat et al. A significant difference in Hb reduction in favor of the PSI group was registered on the last day of stay (p = 0.0084) and significant treatment effect (p = 0.027) on Hb reduction after intervention was found with a regression model for longitudinal measurements. This study demonstrated that PSI leads to a significant trend in earlier Hb regain. These promising results suggest a beneficial effect of PSI in blood loss reduction.