Abstract
Given the higher incidence of bone tumors in younger populations, achieving post-operative biomechanical stability is critical to maintaining long-term mobility. The objective of this study was to evaluate the biomechanical impact of endoprosthetic reconstruction in patients with distal femur and proximal tibia bone tumors in comparison with a control group. The Embase, Scopus, PubMed, and Cochrane databases were systematically searched until January 2025, according to PRISMA guidelines. Heterogeneity was assessed via Cochran's Q statistic and quantified using the I(2) statistic. A total of 23 studies with 692 participants were included, providing data on gait, knee muscle strength, energy expenditure during walking, physical activity level, balance, and joint position sense. Patients demonstrated significant reductions in gait velocity, cadence, and stride length relative to healthy controls, with abnormalities also observed in ground reaction forces, joint internal moments, and joint power. Additionally, both knee flexion strength and extension strength decreased markedly. This study highlights that endoprosthetic reconstruction substantially altered the biomechanical characteristics of the lower limb in patients with distal femur and proximal tibia tumors. These findings have shown the need for further refinement of surgical techniques, rehabilitation strategies, and follow-up programming.