Added value
First, conventional indentation testing devices perform mechanical testing at the mm to cm scale, so they
cannot assess tissue properties at the cellular to molecular level, i.e. at the scale were the biochemical
processes occur and also where most diseases start. Hence, reliable detection of alterations occurring
at all levels of the cartilage architecture is crucial for obtaining a more comprehensive understanding
eventually leading towards an early diagnosis of the disease which, in turn, is a prerequisite for
developing more effective interventions for stopping or even curing osteoarthritis. Second, from the
perspective of orthopedic surgeons, the initial key application of the arthroscopic AFM is in the quality
control of transplanted autologous cartilage tissue as well as of tissue engineered constructs (both
approaches are already available to the clinician) where it is of major interest to trace the development
of the transplanted or tissue engineered cartilage over time in terms of mechanical stability and
biocompatibility. Third, unlike any other applied technique used for assessing the morphological and
biomechanical state of articular cartilage the AFM enabled us to directly image, measure and manipulate
the tissue in situ by employing multifunctional tips.
In the context of new applications of nanoscience, the arthroscopic AFM will move from the bench to the
patient. The arthroscopic AFM might be just the beginning of a new generation of nanotools for minimally
invasive interventions of other parts of the body such as, for example, the detection of vulnerable plaques
in the heart coronary arteries by a catheter-based approach. In that perspective, we are still living in
the “stone age” of scanning probe-based clinical tools. However, we believe that scanning probe
devices will eventually help surgeons to more effectively detect diseases and to repair the human body.