Does tibial sclerosis severity infuence bone resorption risk following total knee arthroplasty?

Abstract

Aims Stress shielding, particularly affecting the proximal medial tibial bone, is a significant concern following total knee arthroplasty (TKA). This study investigates how tibial sclerosis severity, implant configurations, and rotational alignment techniques infuence bone resorption patterns in the medial proximal tibia. Methods Finite element analysis (FEA) was performed using tibial models with four sclerosis levels (0 to 3) representing progressive sclerosis penetration. Four implant configurations combining baseplate shapes (symmetrical vs anatomical) and keel designs (longer (40 mm) vs shorter (30 mm)) were evaluated with two rotational alignment protocols, generating 32 models (4 & times; 4 & times; 2). Bone resorption rates in four medial cortical regions were quantified using strain energy density (SED) criteria. Results A dose-dependent relationship was demonstrated between sclerosis severity and bone resorption rates. In the total medial cortical region, a substantial increase occurred at Level 3 over Level 0 (67.8% vs. 64.8%, respectively, p < 0.001). Keel design emerged as the dominant factor, with shorter keels demonstrating significantly lower absolute resorption rates than longer keels across all sclerosis levels (59.9% to 64.0% vs. 69.8% to 71.7%, p = 0.029). However, when changes were analyzed relative to baseline sclerosis severity, shorter keels exhibited significantly greater increases in bone resorption rates than longer keels (4.1% vs 1.9% at Level 3, p = 0.029), indicating greater sensitivity to sclerosis progression. Contrary to implant configurations, no significant differences were observed between the maximum-coverage method and Insall&apos;s method across all sclerosis severity levels (p = 0.486). Conclusion Proximal medial tibial sclerosis severity demonstrates a clear dose-dependent relationship with bone resorption risk following TKA. Although shorter keel configurations provide lower absolute bone resorption rates, they exhibit greater sensitivity to sclerosis progression than longer keels. Rotational alignment techniques showed no significant effects on bone resorption patterns in sclerotic bone conditions. These findings support preoperative sclerosis assessment for surgical planning and highlight the complex interaction between implant design and bone quality.