Cartilage wear or arthrosis of the knee could be quite painful, especially for elderly patients. With aging, cartilage will become eroded and thinner by the time and movements of the knee joint will become limited. Pain could appear even at night or while sleeping and the only solution is seemingly the replacement of the cartilage by implanting knee prosthesis.
Many people fear this, yet everybody is entitled to make their own decision whether or not to undertake such a big surgery. For example, with considering if the patient can expect the support of the family or other helpers during post-operative rehabilitation.
Even if the date of operation couldn't be canceled, it could still be deferred with some conservative solutions, perhaps without a hyaluronate injection that helps restore joint fluid.