BACKGROUND: Talus is a critical component of the ankle joint that allows multidirectional movement essential for gait and mobility. Talus prostheses are typically used in cases of severe trauma, avascular necrosis, or end-stage arthritis. Adjacent joint arthritis is the most common complication after total talar replacement (TTR). While intervention is rarely required, varying degrees of postoperative degenerative changes have been reported in surrounding joints. Therefore, a detail evaluation of /the mechanical stability and stress distribution within talus prostheses is crucial. Recent advancements, including patient-specific implants and improved biomaterials, show promise in enhancing long-term outcomes and reducing complication rates. AIM: This study investigates the mechanical stability and stress distribution changes in a talus prosthesis after the sequential removal of surrounding ligaments and the application of varying thicknesses of cartilage overlays. METHODS: Finite element analysis (FEA) was employed using CT data to create a 3D model of the talus prosthesis. The model was refined using Mimics, Geomagic, and SolidWorks, and then analyzed with Ansys. The mechanical properties of bone, prosthesis, skin, ligament, and cartilage were incorporated into the model. Various ankle positions, including neutral, dorsiflexion (5° and 10°), and plantarflexion (5°, 10°, 15°, 20°and 30°), were simulated under different ligament removal conditions. RESULTS: The sequential removal of surrounding ligaments, including lateral, medial, sinus tarsi, and talonavicular ligaments, did not significantly affect the stability of the talus prosthesis. Stress values ranged from 2.2257 to 3.0218 MPa, and displacement values were stable around 1.6611 to 2.2119 mm across different conditions. By comparing the effects of different cartilage thicknesses on contact area and contact stress across various flexion angles, we have the optimized the cartilage thickness, and identified a 0.5mm cartilage overlay resulted in stress distributions most similar to a normal ankle joint, enhancing the prosthesis performance. CONCLUSION: The study demonstrates that the removal of surrounding ligaments does not compromise the stability of the talus prosthesis. Importantly, a 0.5 mm cartilage overlay is optimal for achieving stress distributions comparable to a normal ankle joint. These findings offer valuable preliminary insights into stress distribution patterns following talus prosthesis implantation; however, they represent an initial step, and further experimental and clinical studies are needed to validate and extend these results. LEVEL OF EVIDENCE: Level V, computational simulation study.