As an orthopaedic surgeon with extensive clinical experience, I am grateful to the University of Leuven giving me the opportunity to conduct reversed translational research: from bed to test bench and back.
I have been interested in total knee arthroplasty since the early days of my residency, and even before that as a student. During my orthopaedic career, I kept asking myself the same questions during each Total Knee Arthroplasty (TKA) procedure, “What am I doing here and why am I doing it this way?”
From my first years of practice in the 1980s, I have felt that there was still a significant need for improvement in the practice of knee replacement. During the 1990s, I became involved in the development of a new version of an existing type of TKA with the special feature of a rotating tibial platform (R.P.). Convinced that this was the new pathway to follow, I collaborated with Dr. Rick Bassett (Harlingen, Texas, USA) and the orthopaedic industry to design the Performance RP (Performance, Biomet Spain Orthopaedics, S.L. Calle Islas Baleares, 50, 46988 Fuente del Jarro, Valencia, Spain). From 1995 through 2007, we conducted a prospective observational study of 1,152 TKAs by a nonrandomized method.
In 2006, I began developing my doctoral thesis, aided by the invaluable guidance of Professor Johan Bellemans, who stimulated me and assisted in the publication of several publications. The kinematic and wear analysis appeared to support benefits from the rotating platform system; however, the patient outcome study failed to show any advantage of the R.P. over other systems.
At that time, the focus of the field of orthopaedics was on accuracy with the introduction of computer aided navigation and later the patient-matched guides. Since patient satisfaction remained less optimal and long-term studies became available that discussed the relationship between restoration of the mechanical axis to 3° varus/valgus and patient outcome, my attention was drawn to ligament balancing issues.
After reading a number of publications that noted quotes as this one, “Looks good, but feels bad.”, I became interested in the function of the soft tissue envelope of the human knee. As a consequence the title of my doctoral thesis became: Collateral Ligament Strain of the Native Human Knee Joint and after Total Knee Arthroplasty.
Subsequently, the actual experimental work was begun to measure the strains in the collateral ligaments during several motor tasks in the native knee as well in the replaced one. During my work as a doctoral student, I was able to investigate existing clinical problems by bringing them back to the experimental laboratory. I attempted to obtain solutions, which might be subsequently useful in a daily orthopaedic practice. My main hypothesis was that restoration of constitutional rather than neutral mechanical alignment may lead to a more physiological strain pattern in the collateral ligaments; therefore, it could potentially be beneficial to patients.
The flowchart of my reasoning developed after observing results in patients and studying the literature is described below. This has evolved from assessing new designs and surgical techniques to more basic investigations evaluating the behavior of the soft tissue envelope in the native and the replaced knee.