A high platelet count is called thrombocytosis. By definition, any platelet count over 450 thousand is considered to be high. However, only levels above 750 thousand are routinely worked up unless other concerning symptoms accompany the thrombocytosis. This is because slightly elevated platelet counts rarely cause any major problems, and they have many causes.
Moderately high platelet counts such as yours sometimes means that another inflammatory disease or infection is ongoing. If you just got over a bad infection, your platelet count will be higher. Your sore right hip makes me a bit concerned for an inflammatory arthritis
. If this is the case, then this could explain your high platelet count. If you get an other complete blood count drawn, and you platelet count is higher, then you may deserve a workup for primary thrombocytosis.
Since a platelet count of 664 thousand does not suggest any particular diagnosis, I think you should first schedule an appointment with your primary care physician
. He or she can take a look at the rest of your complete blood count to look for any other abnormalities. In addition, your doctor
can order blood tests to look for other common causes of a mild elevation in platelet count. If something comes back positive, you may need referral to a specialist.