Rachitic change and vitamin D status in young children with fractures.

Objective: To examine the association between rachitic changes and vitamin D levels in children less than 2 years old with fractures.

Methods: Children less than 2 years old who were admitted to a large children's hospital for a fracture and underwent a skeletal survey were included. Two pediatric radiologists blinded to the children's vitamin D levels independently reviewed the skeletal surveys for the following rachitic findings: demineralization, widened sutures, rachitic rosary, Looser zones, and metaphyseal changes. Kappa coefficients were calculated to assess inter-rater agreement. Logistic regression was used to test the association between vitamin D level and rachitic findings.

Results: There were 79 subjects (40 female and 39 male) with a median age of 4 months. Vitamin D levels ranged from 11.6 to 88.9 ng/ml and were low in 27. Questionable demineralization was noted in seven subjects; mild to moderate demineralization was observed in four subjects. Widened sutures were noted in seven subjects, many also with concurrent intracranial hemorrhage. Lower vitamin D levels were associated with increased odds of demineralization after adjusting for age, gender, and prematurity (P < 0.015). An association was not found between the vitamin D level and suture widening (P = 0.07). None of the cases demonstrated Looser zones, rachitic rosary, or metaphyseal changes of rickets.

Conclusions: Infants and toddlers with fractures frequently have suboptimal vitamin D levels, but radiographic evidence of rickets is uncommon in these children.