Oligoarthritis (persistent and extended) and polyarthritis rheumatoid factor negative are the most prevalent of the seven types. These facts suggest an environmental component to the occurrence of juvenile arthritis. Children younger than age 6 accounted for 45% of SPARC discharges. Ambulatory Care During 2008-2010, physician visits for juvenile arthritis averaged more than1 million per year. Costs In 2012, total hospital charges related to SPARC was $4.45 billion.1 Top of Page VIII. For example, for systemic type JIA, about 50% of cases develop short stature (<95th percentile) in adulthood. Overall, about 30% of people with JIA had significant functional limitations 10 or more years after onset.1 Top of Page IX. Unique Characteristics Transient childhood arthritis may follow certain infectious diseases.