An adolescent girl with infantile osteopetrosis presenting with a proximal femur fracture

摘要

Infantile osteopetrosis is a rare autosomal recessive genetic disorder that is characterised by abnormal osteoclastactivity leading to increased bone density [1]. It usually presents during infancy and the survival beyond the first decadeof life is rare [2]. A 15-year-old girl fell out of bed and presented to the emergency department with pain and deformity ofright thigh. She was a child of consanguineous parents and was diagnosed with osteopetrosis during infancy based onthe classical radiological changes (diffuse sclerotic bone changes) and clinical features [3]. She had multiple complicationssuch as severe global developmental delay, growth retardation (less than 3 rd percentile), seizure disorder, bilateralpseudoproptosis with visual impairment, bilateral hearing impairment, obstructive sleep apnoea, hepatosplenomegaly,anaemia and thrombocytopenia. She did not have previous fractures. She was haemodynamically stable on admission.X-rays showed a diffuse dense skeleton (Figure 1A) with a rugger-jersey spine (Figure 1C) and a right proximal femurfracture (Figure 1B-Arrow). The distal pulses were felt with an oxygen saturation of 98%. She was managed non-operatively with skin traction and analgesics and was later lost to follow up. Although this condition is well described,it is most unusual for infantile-onset osteopetrosis of such severe degree to survive up to adolescence and such patientsinvariably have multiple complications. We opted to manage the fracture non-operatively as internal fixation is extremelychallenging in such patients.