The doctoral dissertation in the field of Applied Physics will be examined at the Faculty of Science, Forestry and Technology, Kuopio campus and online.
What is the topic of your doctoral research? Why is it important to study the topic?
Osteoarthritis (OA) is a degenerative joint disease affecting over forty-six million individuals in the European Union alone. The disease continues to present significant challenges in healthcare due to its poorly understood mechanisms and the lack of an effective early diagnostic tool. My doctoral thesis made significant advances in understanding the progression of OA and the development of new approaches for its early detection and treatment. The PhD thesis employed a multidisciplinary approach, combining mechanical testing, spectroscopy, and machine learning to explore the progression of OA at both cellular and tissue levels.
What are the key findings or observations of your doctoral research?
A key finding of the thesis is the identification of the cartilage pericellular matrix (PCM), a narrow region surrounding the cell, as the first region to experience OA-related changes. These changes impair cellular function, initiating a cascade of degeneration that spreads to the extracellular matrix in advanced disease stages. The study also highlights that cartilage degradation is not uniform, with tibial cartilage showing faster mechanical deterioration and reduced stiffness compared to femoral cartilage, offering new perspectives for precise diagnostics. A groundbreaking aspect of the research is the development of a diagnostic method using near-infrared (NIR) spectroscopy combined with machine learning. This innovative technique demonstrated the ability to distinguish healthy cartilage from early OA-affected tissue with high sensitivity, paving the way for a real-time diagnostic tool that could transform procedures like arthroscopic surgery.
How can the results of your doctoral research be utilised in practice?
The findings of the thesis have several practical implications. By uncovering the early biochemical changes in the PCM, the research provides a foundation for therapies to restore cells and PCM function to maintain tissue health and slow disease progression. Furthermore, the compositional and mechanical differences identified in cartilage across joint regions can enhance computational models used to predict OA progression, enabling tailored interventions for individual patients. This research underscores the importance of addressing OA at its earliest stages. By focusing on the mechanisms behind the disease and improving diagnostic capabilities, we can create targeted therapies that fundamentally improve patient outcomes.
What are the key research methods and materials used in your doctoral research?
The research involved analyzing human cartilage samples from cadaveric knees using biomechanical testing to assess stiffness and functional properties, spectroscopy to investigate chemical composition, and machine learning models to classify disease severity. Samples were graded following the Osteoarthritis Research Society International (OARSI) guidelines, revealing critical biochemical and mechanical changes associated with OA progression. This dissertation is a significant contribution to the field of osteoarthritis research as it provides a pathway to earlier diagnosis, enabling targeted and personalized treatments to address the growing global burden of osteoarthritis.
The doctoral dissertation of Awuniji Linus, MSc, entitled Infrared spectroscopic and biomechanical characterization of human articular cartilage and chondrocyte microenvironment will be examined at the Faculty of Science, Forestry and Technology, Kuopio Campus and online. The opponent will be Professor Janne Ihalainen, University of Jyväskylä, and the custos will be Adjunct Professor Petri Tanska, University of Eastern Finland. Language of the public defence is English.
