Prevalence of Vitamin D Deficiency in Korean Children Presenting with Nonspecific Lower-Extremity Pain

PURPOSE Although interest in the role played by vitamin D in bone health is increasing, little is known about the role of this vitamin in musculoskeletal pain in children. This study aimed to assess the prevalence of vitamin D deficiency in children presenting with nonspecific lower extremity pains. MATERIALS AND METHODS From 2011 to 2012, 183 children underwent evaluation for nonspecific lower-extremity pains. Patients with valid causes, such as fractures or transient synovitis, were excluded, as were those with underlying medical conditions, such as cerebral palsy and metabolic disease. Ultimately, 140 patients met the inclusion criteria. Levels of serum 25-hydroxy vitamin D [25-(OH)D], the ideal indicator of vitamin D status, were measured in these children. RESULTS Eighty-seven boys (62.1%) and 53 girls (37.9%) were included. The mean age at presentation was 5.2 years (range, 2-15). Serum 25-(OH)D levels were <10 ng/mL in 5.7% of patients, 10 to <20 ng/mL in 51.4%, 20 to <30 ng/mL in 37.9%, and ≥30 ng/mL in only 5.0%. Most patients visited the hospital in the winter (41.4%) (summer, 12.9%), and serum 25-(OH)D levels were also lowest in the winter (17.2±5.5 ng/mL). CONCLUSION This study found a high prevalence of vitamin D deficiency or insufficiency in Korean children with nonspecific lower-extremity pains, indicating a positive association between vitamin D deficiency and growing pains. More attention should be directed toward vitamin D and its role in the optimization of bone health.