Coloured X-ray of the hands of a female 85-year-old patient. The scan shows bone demineralisation (dark orange). There is major osteoarthritis attacking the finger joints. Osteoarthritis (or arthrosis) is a common degenerative disease characterised by a loss of the cartilage that lines the joints between bones. This leads to pain, swelling and occasionally may result in the loss of function of the affected joint.