Innovations in revision total knee arthroplasty

Osteoarthritis (OA) is the most common joint disorder in the world and total knee arthroplasty (TKA) is thought to be the gold standard for the surgical treatment of end-stage OA. Despite good results, a significant proportion of patients need to have their knee prosthesis replaced, and an increase of the number of these so called revision TKAs (rTKAs) is seen and is expected to grow further.This thesis focuses on new techniques in rTKA and is divided into three parts: options during rTKA, alignment measurements and computer-assisted surgery (CAS).In the first part of this thesis survival rates were compared between primary and specially designed revision prostheses when implanted during rTKA. Trabecular Metal (TM) cones are designed to fill up major bone defects. Tibial components can be implanted in combination with a stem, but it is unclear whether this is necessary after reconstruction with a TM cone. This was investigated in this thesis. Prosthesis position is generally measured on conventional long-leg radiographs, but these measurements are not always accurate. With the EOS 2S/3D system the prosthesis position can be measured in 3D. In the second part of this thesis it is investigated whether EOS 3D measurements can be an alternative for measuring prosthesis position. CAS is developed to improve knee prosthesis position. It is not investigated yet if CAS also improves rotation of the prosthesis. It is also unknown whether CAS improves prosthesis position when used during rTKA. Both are being investigated in the third part of this thesis