Alcohol-associated osteonecrosis of the femoral head with subsequent development in the contralateral hip: A report of two cases

Although the pathogenesis of non-traumatic osteonecrosis of the femoral head (ONFH) has not been clarified, high-dose oral corticosteroid therapy and heavy consumption of alcohol have been associated with its occurrence [1e3]. Epidemiological surveys in Japan have found that 34% of ONFH patients have a history of heavy alcohol consumption [1]. The necrotic area of ONFH is determinedwhen it occurs, and the possibility of necrotic area extension is extremely low even if the patient continues taking oral corticosteroids or consuming large quantities of alcohol. The probability of ONFH occurring in both femoral heads is 50e80% [4], with bilateral ONFH thought to occur at almost the same time. Patients with unilateral ONFH rarely develop new ONFH in the contralateral hip. To our knowledge, only two previous case reports have described the occurrence of new ONFH in the contralateral hip: one with alcohol associated ONFH [5] and the other accompanying an increased dosage of corticosteroid [6]. This report describes two patients with alcoholassociated ONFH who developed ONFH of the contralateral hip following treatment of the first side. The patients and their families were informed that data from the cases would be submitted for publication, and gave their consent.