David Michael Ayoub MD, Presenter: Nothing to Disclose

Marvin Miller MD, Abstract Co-Author: Nothing to Disclose

Chuck Hyman MD, Abstract Co-Author: Nothing to Disclose

There is a high prevalence of hypovitaminosis D (HvD) in pregnant women, neonates and young infants. Furthermore, rickets is included in the differential diagnosis of fractures in alleged nonaccidental injury (NAI). The purpose of our study was to characterize and assess the prevalence of radiographic signs of healing rickets associated with HvD in infants with unexplained fractures.

We reviewed pertinent medical records and analyzed radiographs of young infants presenting with unexplained fractures and lab confirmed HvD in either infants and/or their mothers.

Twenty infants whose mean age at presentation was 11.9 ± 6.1 weeks-old (range 4-22 weeks) were eligible for the study. Mean 25-hydroxyvitamin D was 24.8 ± 10.4 ng/ml (range <4.0 – 45.0) in infants and 16.1 ± 4.3 ng/ml in mothers (range 7.6 – 24.0). Each infant had multiple signs of metabolic bone disease, including calvarial mineralization defects (75%), intracortical tunneling (65%), subperiosteal resorption (50%), Looser Zones (45%), kyphoscoliosis (50%), and mild bowing deformities of the distal tibia or mid fibula (70%) All infants had fractures (mean= 9.4 ± 5.0 per infant; range 1-37) that were usually clinically occult. Findings indicative of healing rickets and recent mineralization of excess osteoid were metaphyseal hyperdense bands (100%), metaphyseal clubbing (95%), periosteal neostosis (45%) and trabecular sclerosis (75%). Classical findings of ulnar cupping (60%) and rachitic rosary (55%) were less common while genu varum and metaphyseal fraying/splaying were not identified. Sixty-five growth plate abnormalities were identified in 16 infants (mean= 4.1 ± 3.0), were radiographically similar to lesions of healing rickets depicted in the medical literature and similar to classical metaphyseal lesions.

HvD in early infancy is associated with multiple fractures and diverse radiographic findings including those consistent with healing rickets.

Recognition of signs of healing rickets in early infancy may be valuable in identifying an underlying state of skeletal fragility and fracture susceptibility and may assist in distinction from NAI.

Ayoub, D, Miller, M, Hyman, C, The Forgotten Signs of Healing Rickets in Early Infantile Hypovitaminosis D.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9016026.html