Pyle disease

Pyle disease is a bone disorder characterized by knock knees (genu valgum), relative constriction of the diaphysis or shaft of the bone and flaring of the metaphysis or end of the bone (Erlenmeyer flask deformity), widening of the ribs and collarbones, flattening of the bones of the spine (platyspondyly), and thinning of outer (cortical) layer of bone. Other findings may include excessive bone formation of the skull. Pyle disease is caused by mutations in the SFRP4 gene and is inherited in an autosomal recessive manner.^[1][2][3] Treatment may include management of resulting bone fractures and other orthopedic concerns.^[4]

Pyle disease in inherited in an autosomal recessive manner, which means both copies of the gene in each cell have mutations.^[1][2] The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they often don't have any signs and symptoms of the condition. Some carriers (obligate heterozygotes) of Pyle disease show minor skeletal changes.^[2]