Abstracts / Bone 45 (2009) S59–S111
Results: To date, 28 cases and 17 controls are enrolled. The mean (±SD) age of cases [7.1 (±1.4) years] and the proportion who were male (61%) did not differ from the controls [7.0 (±1.5) years] and 64% respectively. The mean 25-hydroxy vitamin D level for cases [22.6 (±7.9) ng/mL, (range 10–38 ng/mL)] was significantly lower than that of controls [29.1 (± 7.5) ng/mL, (range 15–46 ng/mL)] (p = 0.009). More cases (11/28, 39%) were vitamin D insufficient compared to controls (2/17, 11.8%, OR = 4.85, 95% CI = 0.92–25.5). All DXA scan results were consistent with normal bony mineralization for age (z-score > −2). The mean total body z-score for cases [0.6 (±0.9)] did not differ significantly from controls [0.9 (±0.9)] (p = 0.25). Conclusions: Mean serum vitamin D levels are significantly lower in African American children with fractures than matched controls. Future analyses will incorporate measurements of calcium and vitamin D intake, physical activity, sun exposure, body mass index and genetic analysis. Vitamin D insufficiency may play a previously unrecognized role in childhood fractures. doi:10.1016/j.bone.2009.04.156
PF-11 Malignant infantile osteopetro-rickets: The paradox of plenty A. Shalash, J. Rajah Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates Objective: The aim of this case report is to highlight: 1) the rare paradoxical presence of rickets in children with osteopetrosis, with its attendant complications. 2) that MIOPR is a medical emergency. Methods: A 3 month infant presented to the orthopedic department with a fracture of the upper third of the R femur. The child was in a cast and in traction. Parents were consanguineous (1st cousins) from Pakistan. Neonatal records revealed that he was investigated for thrombocytopenia. Weight and height measurements were on the 3rd centile. Clinical exam revealed, frontal bossing, widened wrists, roving nystagmus with pale optic disks and 4–5 cm hepatosplenomegaly. Results: Skeletal survey revealed osteopetrosis and rickets as well as the fracture femur. CT scan and MRI showed narrowing at the optic foramina. ALP was 1450 IU/L. Calcium was 2 mmol/L and phosphorus 0.69 mmol/L. Intact PTH was 29.1 pmol/L and 25 hydroxy vit D 14 nmol/L. Treatment consisted of calcium, calcitriol, ergocalciferol and interferon gamma. Conclusions: Unless early diagnosis is made and therapy started, these children die of infection or bleeding (encroachment of marrow space) or get permanent disability (blindness and deafness from compression of the optic and auditory foraminae and nasal obstruction from thickening of nasal bones). Rickets develops paradoxically when the Ca × PO4 product is decreased. Even though total body Ca is increased, it remains “trapped” in bone because of osteoclast dysfunction. Rickets further complicates the picture by promoting fractures, causing further irritability and poor feeding. Osteopetro-rickets may also attenuate the effectiveness of bone marrow transplantation as the new osteoclasts are unable to resorb bone in osteoid. doi:10.1016/j.bone.2009.04.157
PF-12 Multiple bone fractures in children — Environmental determinations A. Rusinska, D. Chlebna-Sokol, I. Michalus, A.M. Prochowska Department of Paediatric Propedeutics and Bone Metabolic Diseases, Medical University of Lodz, Lodz, Poland
S99
Aim: The aim of the study was the analysis of the relationships between selected environmental factors and bone fractures in children. Patients and methods: The study comprised 112 children aged 5–17 years, 81 patients with history multiple bone fractures and 31 healthy patients in control group. In all children densitometric examination of the skeleton with DXA method at total body and spine was taken. Moreover questionnaire examination taking into consideration the environmental factors which are probably connected with bone fractures was carried out. Results: In examined group more children than in controls were inhabitants (90 v. 78%, p < 0.05). The mean fracture number was higher in patients subjected to tobacco smoking (5.3 v. 3.3, p < 0.05). There was no observed relationship between mean time of sunlight exposure or number of children in family and fractures. Fathers of children with fractures predominantly have a vocational education (47%), in control group the most often was mean technical education (35%); there was negative correlation between the father's education and the number of fracture (R = − 0.29, p < 0.05). There was an observed significant relationship between the time of children school physical education and bone mineral density (R = 0.27 i 0.22, p < 0.05). Moreover, there was a negative correlation between the time of physical home activity and fracture number (R = − 0.26, p < 0.05). Conclusions: Multiple bone fractures in children may be also determined by environmental factors. Exposure to tobacco smoking, decreased physical activity and father's education seem to be connected with consecutive fractures in the developmental period. Acknowledgements: The study was partly financed by grant no. N407 063 32/2713. doi:10.1016/j.bone.2009.04.158
PF-13 Bone fractures in children — Evaluation of bone mineral density by dual energy X-ray absorptiometry and quantitative ultrasound D. Chlebna-Sokol, A. Rusinska, J. Golec, I. Michalus Department of Paediatric Propedeutics and Bone Metabolic Diseases, Medical University of Lodz, Lodz, Poland Aim: To evaluate the relationship between densitometry and quantitative ultrasound parameters of bone mineral density and fractures in children. Material and methods: The study involved 380 children aged 5–18 years, including 157 girls and 223 boys. In 10 children vertebral fractures were reported and 177 of them suffered from present or past long bones fractures. Dual energy X-ray absorptiometry and ultrasound examination of calcaneus was performed to assess bone mineral density. Results: The study revealed a statistically significant positive correlation between the results of bone mineralization obtained by densitometry and ultrasounds. The highest correlation coefficients were observed for Stiffness and BUA (broadband ultrasound attenuation) parameters and bone mineral density measured in total body. The analysis of the relationship between bone mineralization measurements and fractures revealed significantly lower mean Zscore parameters both in total body and spine in children with vertebral fractures. The values of ultrasound parameters in this group of patients were also lower, but the differences were not statistically significant. There were no significant differences observed between the patients with and without fractures of long bones for all bone mineralization results, even after detailed analysis in each age group was performed.