Presently, our knowledge of the hip capsule and its role in human mechanics remains largely incomplete. Therefore, this research proposal seeks to address this critical gap by investigating the active and passive roles of the hip capsule in hip mechanics and particularly how this impacts the outcomes of hip replacement surgery. Specifically, we will examine the impact of implant design, anatomical variance, and surgical handling on the mechanical properties of the hip capsule. This research has the potential to enhance surgical techniques and implant designs, optimizing patient outcomes and enhancing long-term performance following hip arthroplasty.