Function of the hand. Also it is one of the most common joint disease allover the world. that is, no one factor triggers the process that results in cartilage. Osteoarthritis of the hand and wrist joints can be classified acording to the actiology into primary ( when no obvious cause can be found ) and secordary ( when it follows a demonstrable abnormality) or clinically according to the numbers of affected joints into monoarti ccular, pauciarticular and polyarticular (generalized) osteoarthritis. But the most commonly used classification is the conbination of the aertiological and the clinical classifications.