Plain radiograph evaluation of concurrent filling of tibial peg holes with bone in cementless total knee arthroplasty

This study aimed to evaluate the effectiveness of a novel technique for securing the tibial component in cementless total knee arthroplasty (TKA) by utilizing resected cancellous bone to fill the peg holes. It was hypothesized that this method would reduce the incidence of radiolucent lines (RLLs) on plain radiographs. To test this hypothesis, a retrospective comparison of plain radiographs from patients who underwent the bone-filling technique (bone filling group) versus those who did not receive this treatment (conventional group) was conducted. Participants were 151 patients (213 joints) who underwent TKA with the NexGen trabecular metal (TM) modular tibia (Zimmer Biomet) from 2011 to 2016 [bone filling group, 54 patients (69 joints); conventional group, 100 patients (144 joints); 3 patients had 1 joint in each group]. Clinical evaluations, plain radiographs, and operative time were compared between groups. The mean follow-up period was 5 years and 5 months. Knee Society Scores and Knee Society Functional Scores did not differ significantly between groups; however, the bone filling group had a significantly lower incidence of RLLs ( p ​< ​0.05) and significantly more longitudinal trabecular thickening below the pegs ( p ​< ​0.05). Multiple logistic regression analysis with the presence/absence of RLLs as the dependent variable revealed a significant effect of bone filling (odds ratio ​= ​2.820, 95% confidence interval 1.033–7.700; p ​< ​0.05). Concurrent peg hole bone filling significantly reduces the incidence of RLLs and significantly increases longitudinal trabecular thickening below the pegs during TKA with the NexGen TM modular tibial component. • Radiolucent lines can appear after cementless total knee arthroplasty. • Peg holes were filled with resected cancellous bone to fix the tibial component. • This study compared plain radiographs in groups with and without bone filling. • Peg hole bone filling significantly reduced the incidence of radiolucent lines. • It also significantly increased longitudinal trabecular thickening below the pegs.