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Influence of Food Restriction Combined With Voluntary Running on Bone Morphology and Strength in Young and Mature Male Rats
Abstracts Advantage competitive binding chemiluminescence immunoassay (reference range 10-68 ng/mL, intra-assay precision 3.9% at 20.3 ng/mL, 3.0% at 49.9 ng/ mL, and 3.6% at 57.8 ng/mL, lower limit of sensitivity 7 ng/mL; Quest Diagnostics Clinical Trials Laboratory Test Development Department, Van Nuys, CA, USA) from a central laboratory. Lumbar spine (L2-L4) BMD was measured by DXA (GE Healthcare Lunar Prodigy). Lumbar spine TBS was derived from DXA lumbar spine examinations. Results: Mean serum (25OHD) level was 27.212.2 ng/ml and mean BMI was 26.95.2 kg/m2. Age, weight, height and BMI were not correlated to serum (25OHD). Age, weight, height, BMI and serum (25OHD) were not correlated to TBS. Conclusion: These results suggest that serum (25OHD) is not a determinant of TBS in postmenopausal women. Further research is needed to identify the determinants of TBS in postmenopausal women. Disclosure of Interest: None Declared
P107 SPEED OF BONE ACCRETION ASSESSED BY DUAL X-RAY ABSORPTIOMETRY (DXA) AND QUANTITATIVE ULTRASOUND (QUS) IN MEXICAN HEALTH WORKERS COHORT STUDY R. Rivas Ruiz1,*, P. Clark2, J. O. Talavera1, J. Tamayo3, G. Huitron4, J. Salmeron5; 1Coordinacion de Investigacion en Salud, Instituto Mexicano del Seguro Social, Mexico City, 2Clincal Epidemiology, Hospital Infantil de Mexico, Mexico City, 3Comite Mexicano para la prevencion de la osteoporosis, Mexico City, 4Universidad Aut onoma del Estado de Mexico, Toluca, 5Instituto Mexicano del Seguro Social, Cuernavaca, Mexico Aims: To assess the speed of bone accretion and critical bone periods in children from 1-25 years by using DXA and QUS in a large Mexican population sample. Methods: This is a longitudinal cross-sectional evaluation of participants in the Mexican Health Workers Cohort Study. DXA and QUS measurements were performed using Sunlight Omnisense 8000P. Locally weighted regression smoothing scatterplot (LOESS) model to identify different phases of bone accretion and sequential stratified model was used using a linear regression model, finally the growth of speed was calculated. Results: A total of 3525 participants aged 1-25 were included. 56.4% were female, we found four different moments of bone accretion using the LOESS. Bone accretion was present in women vs. men as follow: From 1-6 years was of 53.04 vs. 20% (p!0.01), 6-13 (63.50 vs. 25%) (p!0.01), 13-19 (90.96 vs. 60.71%) (p50.03) and 19-25 years (98.83 vs. 97.86%) (p50.56) until peak bone mass. Conclusion: Our study shows the age- and sex-dependent changes and different phases of bone development as assessed with SoS and DXA. Identify the bone accretion in each stage could help to promote healthy lifestyles to prevent OP in elderly. Acknowledgement: Thanks to Dr Gabriela Huerta for all the support for this paper Disclosure of Interest: None Declared
P108 INFLUENCE OF FOOD RESTRICTION COMBINED WITH VOLUNTARY RUNNING ON BONE MORPHOLOGY AND STRENGTH IN YOUNG AND MATURE MALE RATS S. Hattori1,*, J.-H. Park2, U. Agata1, M. Higano1, M. Oda1, N. Omi1; 1University of Tsukuba, Tsukuba, Japan, 2Konkuk University, Seoul, Republic of Korea Aims: Athletes, in particular endurance athletes are chronically exposed to a state of low energy availability due to insufficient dietary energy intake and massive exercise energy expenditure. Low energy availability sometimes causes bone fragility, thereby increasing the risk of bone disorders. However, the bone disorders such as stress fracture are less frequent in the mature athlete than that in the young athlete. We hypothesized the influence of low energy availability on
405 bone tissue was different according to the developmental stage. The purpose of this study was to examine the influence of food restriction combined with voluntary running training on bone morphology and strength in young and mature male rats. Methods: Young (4 weeks old) and mature (14 weeks old) male Sprague Dawley rats were divided randomly into eight groups, respectively: the Control (C) group, Food restriction (R) group, Exercise (Ex) group, and Food restriction plus exercise (REx) group. For the R and REx groups, 30% food restriction was carried out in comparison with the C group. The Ex and REx groups were housed with free access to a wheel cage (circumference -1 m). Bone strength, BMD, bone architecture were measured after a 13-week experimental period. One-way analysis of variance was used to test for statistically significant differences among groups. If a significant difference was detected among groups, these groups were further evaluated using the post hoc Turkey test. The significance level for major effects was set at p!0.05. Results: In the young group, the bone strength in the REx group was significantly lower than that in the C group (p!0.001). BMD was significantly lower than that in the C group (p!0.05). Moreover, trabecular bone volume and cortical bone volume were significantly lower than that in the C group (p! 0.05, p!0.001, respectively). In the mature group, the bone strength was not significantly lower in the REx group compared with the C group. The BMD, trabecular bone volume, and cortical bone volume showed no difference compared with the C group. Conclusion: These findings indicate that the food restriction combined with voluntary running training caused the low bone strength in the young and mature rat. It caused the low BMD and microarchitectural deterioration in the young rats. In contrast, it little affected the BMD and the bone morphology in the mature rats. Our results suggested the low energy availability likely to greatly influence young rats from mature rats. Acknowledgement: We acknowledge the grand of Ibaraki Society of Physical Education, Health and Sport Science. Disclosure of Interest: None Declared
P109 OSTEOPOROTIC ELBOW: DOES MICRODENSITOMETRY COULD IMPROVE OSTEOSYNTHESIS? S. Abrassart1,*, P. Hoffmeyer2; 1Orthopaedic Surgery, 2HUG, Geneva, Switzerland Aims: Elbow is a complex joint and synthesis quite delicate. Elbow fractures, especially distal humeral part and olecranon are very common in old people. We aimed to provide an anatomical basis for surgical techniques in elbow osteosynthesis. The purpose of this study was to investigate the 3-dimensional trabecular BMD in the humeral distal part and proximal ulna to determine areas of low density. Limited information exists for elbow to understand its mechanical behaviour Methods: 20 fresh elbows without any surgery or arthritis were included (10 men, 10 women) mean age 75 years. We had excluded surgery and arthritis .The humeral part and the olecranon was analyzed in a mCT (HR-pQCT Scanco) with slice of 80 microns. Manual definition of the areas; external column, internal column and center. Software Scanco provided to us, osseous volume, trabecular thickness, trabecular space, trabecular number and bone density (BV/TV). Results: Humeral part: Density of internal column (BV/TV50.4) is greater than the density of the external column (BV/TV50.2) .The center is very rich in trabeculae but these one are very thin and far from each other (TB sp51 mm) The density of the center is the same that the external column (BV/TV50.2). The shape and the direction of the trabeculae are described. Olecranon and ulna proximal have a bone architecture quite complex: Corono€ıdal process and olecranon beak have a high density .There is an area of bone fragility between proximal ulna and metaphysis. Conclusion: Microarchitecture of distal humeral bone and proximal ulnar may explain the map of the fractures. Emphasis has traditionally been placed on cortical bone as quality predictor due to its stiffness for achieving primary stabilisation. However, screws are mainly in contact with cancellous part of bone, and mechanical characteristics of cancellous bone also influence the load-bearing capacity of implant-bone union. This study is interesting in showing areas of poor cancellous bone quality and may help to improve surgical techniques. References: Diederichs G, et al. J Shoulder Elbow Surg 2009;18:399 Disclosure of Interest: None Declared
Journal of Clinical Densitometry: Assessment & Management of Musculoskeletal Health
Volume 17, 2014
P107 SPEED OF BONE ACCRETION ASSESSED BY DUAL X-RAY ABSORPTIOMETRY (DXA) AND QUANTITATIVE ULTRASOUND (QUS) IN MEXICAN HEALTH WORKERS COHORT STUDY R. Rivas Ruiz1,*, P. Clark2, J. O. Talavera1, J. Tamayo3, G. Huitron4, J. Salmeron5; 1Coordinacion de Investigacion en Salud, Instituto Mexicano del Seguro Social, Mexico City, 2Clincal Epidemiology, Hospital Infantil de Mexico, Mexico City, 3Comite Mexicano para la prevencion de la osteoporosis, Mexico City, 4Universidad Aut onoma del Estado de Mexico, Toluca, 5Instituto Mexicano del Seguro Social, Cuernavaca, Mexico Aims: To assess the speed of bone accretion and critical bone periods in children from 1-25 years by using DXA and QUS in a large Mexican population sample. Methods: This is a longitudinal cross-sectional evaluation of participants in the Mexican Health Workers Cohort Study. DXA and QUS measurements were performed using Sunlight Omnisense 8000P. Locally weighted regression smoothing scatterplot (LOESS) model to identify different phases of bone accretion and sequential stratified model was used using a linear regression model, finally the growth of speed was calculated. Results: A total of 3525 participants aged 1-25 were included. 56.4% were female, we found four different moments of bone accretion using the LOESS. Bone accretion was present in women vs. men as follow: From 1-6 years was of 53.04 vs. 20% (p!0.01), 6-13 (63.50 vs. 25%) (p!0.01), 13-19 (90.96 vs. 60.71%) (p50.03) and 19-25 years (98.83 vs. 97.86%) (p50.56) until peak bone mass. Conclusion: Our study shows the age- and sex-dependent changes and different phases of bone development as assessed with SoS and DXA. Identify the bone accretion in each stage could help to promote healthy lifestyles to prevent OP in elderly. Acknowledgement: Thanks to Dr Gabriela Huerta for all the support for this paper Disclosure of Interest: None Declared
P108 INFLUENCE OF FOOD RESTRICTION COMBINED WITH VOLUNTARY RUNNING ON BONE MORPHOLOGY AND STRENGTH IN YOUNG AND MATURE MALE RATS S. Hattori1,*, J.-H. Park2, U. Agata1, M. Higano1, M. Oda1, N. Omi1; 1University of Tsukuba, Tsukuba, Japan, 2Konkuk University, Seoul, Republic of Korea Aims: Athletes, in particular endurance athletes are chronically exposed to a state of low energy availability due to insufficient dietary energy intake and massive exercise energy expenditure. Low energy availability sometimes causes bone fragility, thereby increasing the risk of bone disorders. However, the bone disorders such as stress fracture are less frequent in the mature athlete than that in the young athlete. We hypothesized the influence of low energy availability on
405 bone tissue was different according to the developmental stage. The purpose of this study was to examine the influence of food restriction combined with voluntary running training on bone morphology and strength in young and mature male rats. Methods: Young (4 weeks old) and mature (14 weeks old) male Sprague Dawley rats were divided randomly into eight groups, respectively: the Control (C) group, Food restriction (R) group, Exercise (Ex) group, and Food restriction plus exercise (REx) group. For the R and REx groups, 30% food restriction was carried out in comparison with the C group. The Ex and REx groups were housed with free access to a wheel cage (circumference -1 m). Bone strength, BMD, bone architecture were measured after a 13-week experimental period. One-way analysis of variance was used to test for statistically significant differences among groups. If a significant difference was detected among groups, these groups were further evaluated using the post hoc Turkey test. The significance level for major effects was set at p!0.05. Results: In the young group, the bone strength in the REx group was significantly lower than that in the C group (p!0.001). BMD was significantly lower than that in the C group (p!0.05). Moreover, trabecular bone volume and cortical bone volume were significantly lower than that in the C group (p! 0.05, p!0.001, respectively). In the mature group, the bone strength was not significantly lower in the REx group compared with the C group. The BMD, trabecular bone volume, and cortical bone volume showed no difference compared with the C group. Conclusion: These findings indicate that the food restriction combined with voluntary running training caused the low bone strength in the young and mature rat. It caused the low BMD and microarchitectural deterioration in the young rats. In contrast, it little affected the BMD and the bone morphology in the mature rats. Our results suggested the low energy availability likely to greatly influence young rats from mature rats. Acknowledgement: We acknowledge the grand of Ibaraki Society of Physical Education, Health and Sport Science. Disclosure of Interest: None Declared
P109 OSTEOPOROTIC ELBOW: DOES MICRODENSITOMETRY COULD IMPROVE OSTEOSYNTHESIS? S. Abrassart1,*, P. Hoffmeyer2; 1Orthopaedic Surgery, 2HUG, Geneva, Switzerland Aims: Elbow is a complex joint and synthesis quite delicate. Elbow fractures, especially distal humeral part and olecranon are very common in old people. We aimed to provide an anatomical basis for surgical techniques in elbow osteosynthesis. The purpose of this study was to investigate the 3-dimensional trabecular BMD in the humeral distal part and proximal ulna to determine areas of low density. Limited information exists for elbow to understand its mechanical behaviour Methods: 20 fresh elbows without any surgery or arthritis were included (10 men, 10 women) mean age 75 years. We had excluded surgery and arthritis .The humeral part and the olecranon was analyzed in a mCT (HR-pQCT Scanco) with slice of 80 microns. Manual definition of the areas; external column, internal column and center. Software Scanco provided to us, osseous volume, trabecular thickness, trabecular space, trabecular number and bone density (BV/TV). Results: Humeral part: Density of internal column (BV/TV50.4) is greater than the density of the external column (BV/TV50.2) .The center is very rich in trabeculae but these one are very thin and far from each other (TB sp51 mm) The density of the center is the same that the external column (BV/TV50.2). The shape and the direction of the trabeculae are described. Olecranon and ulna proximal have a bone architecture quite complex: Corono€ıdal process and olecranon beak have a high density .There is an area of bone fragility between proximal ulna and metaphysis. Conclusion: Microarchitecture of distal humeral bone and proximal ulnar may explain the map of the fractures. Emphasis has traditionally been placed on cortical bone as quality predictor due to its stiffness for achieving primary stabilisation. However, screws are mainly in contact with cancellous part of bone, and mechanical characteristics of cancellous bone also influence the load-bearing capacity of implant-bone union. This study is interesting in showing areas of poor cancellous bone quality and may help to improve surgical techniques. References: Diederichs G, et al. J Shoulder Elbow Surg 2009;18:399 Disclosure of Interest: None Declared
Journal of Clinical Densitometry: Assessment & Management of Musculoskeletal Health
Volume 17, 2014