Computer-assisted arthroplasty using bio-engineered autografts.

Recent advances in tissue-engineered cartilage open the door to new clinical treatments of joint lesions. Common to all therapies with in-vitro engineered autografts is the need for optimal fit of the construct, to allow screwless implantation and optimal integration into the live joint. Computer Assisted Surgery techniques are prime candidates to ensure the required accuracy while at the same time simplifying the procedure. A pilot study has been conducted aiming at assembling a new set of methods to support ankle joint arthroplasty using bio-engineered autografts. Computer assistance allows planning of the implant shape on a CT image, manufacturing the construct according to the plan and interoperatively navigating the surgical tools for implantation. A rotational symmetric model of the joint surface was used to avoid segmentation of the CT image; a new software was developed to determine the joint axis and make the implant shape parameterisable. A complete cycle of treatment from planning to operation was conducted on a human cadaveric foot, thus proving the feasibility of computer-assisted arthroplasty using bio-engineered autografts.