Hi
Thanks for the query to H C M .
As you mentioned that your grand daughter is just 6 years old and she is having painful knee joint for 4 years .
Still diagnosis is not established , ii is very peculiar .
May be due to these possibilities , these include:
1
Rickets due to dietary or absorption deficiency of Vitamin D .
2 Osgood-Schlatter's disease in this disease proximal tibial
epiphysis gradually be avulsed from the shaft which is part of metaphysis ( since pain is almost for 4 years ,so we should concentrate rare disease ).
3
Gout ,
rheumatoid arthritis are other diseases.
In my opinion without physical examination , reports and findings it is very difficult to establish any diagnosis merely on the basis of this short history.
So upload complete data or consult one more ORTHOPEDIC doctor for diagnosis .
Hope this information will be useful for you.
Good luck for little one.