Short answers, pulled from the story.
Arthritis is a general medical term for a specific type of joint disorder where the smooth cartilage layer that lines a joint is lost. This mechanical failure results in bone grinding on bone during movement.
Osteoarthritis pain tends to be related to activity initially then becomes constant while rheumatoid arthritis is generally worse in the morning associated with stiffness lasting over 30 minutes. Other symptoms include swelling, redness, warmth, decreased range of motion, and fatigue.
John Charnley completed the first hip replacement in England to treat arthritis during the 1960s establishing modern surgical standards for joint disorders. Joint replacement surgery known as arthroplasty has been incorporated since the 1950s to repair damage restore function or relieve pain.
The first known traces of human arthritis date back as far as 4500 BC found in skeletal remains of Native Americans in Tennessee and Olathe Kansas. Evidence has been discovered throughout history from Ötzi mummy found along border of modern Italy and Austria to Egyptian mummies.
A CDC survey based on data from 2013 to 2015 showed 54.4 million adults had self-reported doctor-diagnosed arthritis representing 22.7% of adults. Disability due to musculoskeletal disorders increased by 45% from 1990 to 2010 making osteoarthritis the fastest increasing major health condition.