Avascular necrosis of the talus in pediatric acute lymphoblastic leukemia: Current concepts

Avascular necrosis (AVN) is a disease due to the interruption of the blood supply to the bone. It is one of the most common and debilitating therapy-related sequelae of the antileukemic treatment and it may not be clinically recognized. Symptomatic AVN have been reported in 1-17% of children with acute lymphoblastic leukemia (ALL) during treatment or thereafter although an incidence of up to 72% of asymptomatic AVN has been detected with systematic screening by magnetic resonance imaging (MRI). In all cases AVN is related to ALL treatment and in particular to high-dose steroids. While the AVN of the hip is frequently reported in the literature, reports regarding AVN of the talus are lacking; moreover, there is little consensus about its incidence, diagnostic algorithm and treatment. Talus is an articular weight-bearing bone with over 60% of the surface covered by cartilage and a specific limited vascular supply. The aim of this article is to provide an up-to-date review about management of avascular necrosis of the talus highlighting the importance of early diagnosis based on ankle MRI imaging in pediatric patients affected with ALL.