Q: My 13 years old son is having hip necrosis because he is using cortisone. Now his MRI shows stage 3. What is the best treatment for the worst case? Is a hip replacement an answer? If we do replace the hip, will he still grow taller as he ages? Do you do hip replacement and how much it costs?

A:AVN of the hip is a serious complication of steroid therapy and occurs particularly in the setting of diseases such as Systemic lupus(SLE). I am unclear about your childs primary diagnosis as it is very seldom that cellcept is used for Henoch Schnolein Purpura. The skin manifestation of HSP can resemble the ones seen in SLE. So I have two suggestions: 1. Clarification of the primary diagnosis as in SLE there are certain antibodies such as anticardiolipin antibodies that thicken the blood and may predispose to AVN. These patients benefit from low dose aspirin. 2. A trail of the drug alendronate under strict medical supervision as there are recent reports that suggest alendronate can stabalize AVN, help in prevention of collapse of the femoral head and relieve the pain as well. Core decompression is not an option as the growth plate would be open at this age. Hip replacement, if needed should be preferably deferred till after growth has been completed.