Total hip arthroplasty (THA) is a highly successful surgical procedure for the treatment of degenerative hip disorders, providing significant pain relief and functional improvement. Increasing life expectancy and higher functional expectations have resulted in a growing number of both primary and revision procedures, highlighting complex challenges such as instability, severe bone loss, and pelvic discontinuity. Modular implant systems allow intraoperative adjustment of key biomechanical parameters, including femoral offset, anteversion, and leg length, thereby optimizing anatomical and functional restoration. In revision settings, modular tapered stems offering distal fixation and modular acetabular shell–liner constructs provide important reconstructive flexibility. However, modular junctions may be associated with mechanical complications such as fretting and corrosion. In cases of advanced acetabular bone loss and pelvic discontinuity, custom-made triflange implants enable anatomical conformity and rigid fixation, representing a valuable reconstructive option. Nevertheless, increased cost, manufacturing time, and limited long-term data remain important limitations. Integration of spinopelvic mobility assessment into surgical planning, along with digital planning tools, additive manufacturing technologies, and artificial intelligence–assisted systems, has shifted THA toward a more personalized and predictive approach. Implant selection should therefore be individualized based on patient-specific biomechanical requirements and clinical characteristics.