Knee joints bear the full weight of a lifetime of movement, yet the tissues that make this possible remain surprisingly difficult to study. When osteoarthritis sets in, cartilage and meniscus gradually deteriorate, but the underlying processes are still murky, partly because the tools most commonly used to examine these tissues each come with significant blind spots. MRI struggles with resolution; histology can only capture a single flat slice and requires destroying the sample in the process.
This PhD project took a different route, asking whether techniques from large-scale research facilities could offer a clearer view. The work focused on three approaches: synchrotron phase-contrast tomography, neutron tomography, and quasi-elastic neutron scattering. Together, these made it possible to examine cartilage and meniscus samples in three dimensions and in a state close to natural, without the preparation steps that traditionally alter tissue structure.
Neutrons proved especially valuable here. Unlike X-rays, they interact strongly with hydrogen, which makes them naturally well-suited to water-rich biological tissues. By swapping ordinary water for heavy water in the samples, the experiments could track how fluid moves through cartilage and meniscus at a scale no existing imaging method had captured directly. The results suggest that water transport in these tissues is considerably more complex than current models assume.
The synchrotron work added another dimension, producing detailed three-dimensional maps of cartilage cells and revealing signs of degeneration that matched – and in some cases surpassed – what classical histology could show. Taken together, the studies establish a baseline for what these techniques can reveal about joint tissue, healthy and diseased alike.
The broader ambition is for future research to build on these methods with sharper, more targeted questions – whether about how degeneration unfolds mechanically, or about what changes when tissue is placed under load. The tools now exist; the next step is putting them to work on the mechanisms that matter.