Radiation enhanced diffusion in cartilages as a physical mechanism underlying radiation treatments of osteoarthritis and related disorders

Abstract

Degradation of joint cartilages can result in osteoarthritis (OA) affecting about 10\% of the US population and responsible for significant hospitalization costs. While observations show that low dose radiation treatments (LDRT) bring improvements for a majority of OA patients, the underlying mechanism is not sufficiently understood. Here, we show how the radiation enhanced diffusion (RED) can boost the molecular transport in cartilages promoting cartilage self-healing rendering a mechanism for the observed positive LDRT effects on OA. Along with quantitative estimates for RED, we predict a related phenomenon of the electric charge build up that allows LDRT schedules promoting desirable types of molecular transports dominated by either positive or negative molecular species. Our analyses call upon further experimental verifications and clinical trials with curative rather than palliative intent. In addition to OA applications, our developed approaches can be useful for sports medicine dealing with damage or degeneration of the articular cartilages.