Rapid Fabrication of Patient Specific Implants for Soft and Hard Tissue Replacement

Abstract

Implanted treatments aim to alleviate pain and restore the natural body. Currently, surgical procedures focus on a modular system, shaping patients to the nearest generically sized implant rather than tailoring to fit patient anatomies. Improper implant sizing or positioning can result in abnormal biomechanics, consequently leading to early failure. The rise in additive manufacturing has presented unique opportunities for patient specific implants. Custom devices have often been associated with shorter operative times, faster recoveries and lower rates of infection. Despite these inherent benefits, key remaining challenges facing its commercial viability include cost, delivery timeframe and quality assurance. This research details the design, development and validation of a system to fabricate patient specific implants through merging traditional and modern manufacturing techniques with patient adaptability. The templating system was explored in two applications, spine and skull reconstruction, with particular focus on the development of a regenerative, biomimetic intervertebral disc replacement. The functional and commercial feasibility of the templating system and resultant implants were examined. The templating system successfully generated a regenerative disc replacement that met geometrical, mechanical and biological requirements. Novel materials were developed into a custom disc implant that supported cell proliferation and biomechanical loads comparable with the native spine. The templating system was also applied clinically, providing superior aesthetic results when surgically used for cranioplasty. The findings of this thesis indicated the rapid templating system may overcome significant logistical limitations in shifting toward individualised treatments. Overall, the presented system exhibited strong functional and commercial potential toward integrating implants that were patient specific anatomically and mechanically into the healthcare domain.