Sickle cell haemoglobinopathy is the third most common genetic blood disorder in Oman. The genetic background of the Omani population is heterogeneous and hence there are several haplotypes including African (e.g. Benin, Bantu) and the Arab-Indian resulting in different disease severity ranging from very mild to very severe. In our population, there are some other factors that can modify the course of the disease like co-inheritance of alpha thalassemia that is highly prevalent in the Omani population (amounting to about 50%) and is believed to be associated with development of avascular necrosis (AVN) of the hip. AVN of the femoral head is a common complication in patients with sickle cell disease (SCD), and collapse of the femoral head occurs in 90% of the patients within five years of the diagnosis of osteonecrosis. In our hospital, we follow more than 500 children with SCD and 32 of them have developed AVN over the last 10 years. Our experience will be descuss in this letter.