Gait After THA: Direct Anterior vs Manual Posterior vs Robotic Posterior

Single-center, three-arm, partially randomized interventional study comparing gait biomechanics after primary total hip arthroplasty (THA) via (1) manual direct anterior approach (DAA), (2) manual posterior approach (PA), and (3) robotic-assisted posterior approach (rPA). One surgeon's patients are randomized to DAA vs PA; the second surgeon's patients receive rPA per routine practice. Outcomes assessors are blinded (motion-capture suit conceals dressings/scars). Gait and sit-to-stand analyses are performed pre-op and at 6 and 12 weeks post-op using a Vicon motion capture system with force plates and surface EMG. Patient-reported outcomes are collected with standard instruments. The trial evaluates short-term biomechanical recovery and patient-reported outcomes across approaches.