Three-dimensional (3D) printing has revolutionized orthopedic surgery by enabling the fabrication of patient-specific implants tailored to individual anatomical requirements. This study evaluates the clinical efficacy, biomechanical performance, and long-term outcomes of 3D-printed custom orthopedic implants. A systematic review of 57 clinical studies and trials was conducted, analyzing implant design, material selection, surgical integration, and postoperative recovery. Results indicate that 3D-printed implants enhance osseointegration, reduce surgical time, and improve functional outcomes compared to traditional implants. Challenges such as regulatory hurdles, cost, and material limitations are also discussed. The findings suggest that 3D printing holds significant promise for advancing personalized orthopedic care, though further long-term studies are needed.