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Juvenile rheumatoid arthritis
Juvenile rheumatoid arthritis is arthritis affecting a child (under 16) in several joints where evidence exists that the condition is autoimmune - ie the child's own immune system is attacking its joints.
Juvenile traction osteochondritis
Juvenile traction osteochondritis is an overuse syndrome where jumping activities in a young person causes excessive pulling of the patellar tendon on the tibial tubercle.