TY - JOUR T1 - Bone JF - Archives of Disease in Childhood JO - Arch Dis Child SP - A56 LP - A58 VL - 90 IS - suppl 2 A2 - , Y1 - 2005/04/01 UR - http://adc.bmj.com/content/90/suppl_2/A56.abstract N2 - J. May1, J. Dutton2, J. Morris3, W. D. Fraser2, A. J. B. Emmerson1, M. Z. Mughal4.1Neonatal Medicine, St Mary’s Hospital for Women & Children, Manchester, UK; 2Clinical Biochemistry, Royal Liverpool Hospital, Liverpool, UK; 3Medical Statistics, University of Manchester, Manchester, UK; 4Paediatric Medicine, St Mary’s Hospital for Women & Children, Manchester, UK Background: In healthy singleton infants 31 to 42 weeks gestation, tibial speed of sound (m/s) measured at median age of 2.1 days after birth increased with gestational age. Method: In this longitudinal study we measured the knee–heel limb length (mm) using an electronic neonatal knemometer (FORCE Institutes, Denmark) and tibial speed of sound using the Sunlight Omnisense quantitative ultrasound device (Sunlight Medical Ltd., Israel), in the same limb, in 82 preterm infants. The median (range) gestation and birth weight of infants was 27 weeks (23 to 37.6 weeks) and 903 grams (418 to 1495 grams), respectively. Measurements were performed weekly; median period of 4 weeks (2 to 14 weeks). There was a significant increase in lower limb length (r 0.96; p<0.001), (see fig 1) but a significant decrease (within subject correlation, r −0.28; p<0.001) in tibial speed of sound with postnatal age (fig 2). Abstract G136, figure 1 Abstract G136, figure 2 Results: In a subgroup of 24 infants, changes in serum concentration of bone specific alkaline phosphatase (BSALP; a marker of bone formation) and urinary excretion of urinary deoxypyridinoline to creatinine ratio (DPD; a non-reducible cross link of collagen that is a marker of bone resorption) were measured on the same day and around the same time as lower limb length and tibial speed of sound measurements. The serum concentration of BSALP (r +0.44; p 0.001) and urinary DPD/creatinine (r +0.24; … ER -