Endochondral ossification in the damaged joint

The worldwide burden of knee cartilage damage and OA is rising rapidly, especially in relatively young patients. When damaged, articular cartilage possesses little regenerative capacity. Joint homeostasis and a process called ‘endochondral ossification’ are disturbed which leads to continued joint degeneration. When total knee arthroplasty is performed in young patients, they are at increased risk for revision arthroplasty later in life. Therefore, more attention for joint preserving strategies is needed. This thesis describes the results of cartilage repair surgery, assessed, among others, by high-resolution MRI. Several factors like previous surgeries, prolonged time of symptoms, and a higher age negatively influence the outcome of cartilage repair surgery. Furthermore, it was assessed how the process of endochondral ossification could be influenced to improve the treatment of cartilage damage in the joint. Finally, an innovative drug delivery system was developed that is able to reduce inflammation in the knee joint and possibly improve the joint homeostasis. The work presented in this thesis demonstrates that the improvement of joint preservation can be addressed at these different levels and from different viewpoints/insights (e.g., cell and patient).