Abstract
Physical activity is beneficial for skeletal development. However, impact sports during adolescence, leading to bone growth retardation and/or bone quality improvement, remains unexplained. This study investigated the effects of in vivo low (LI), medium (MI), and high (HI) impact loadings applied during puberty on bone growth, morphometry and biomechanics using a rat model. 4-week old rats (n = 30) were divided into control, sham, LI, MI, and HI groups. The impact was applied on the right tibiae, 5 days/week for 8 weeks mimicking walking (450 µε), uphill running (850 µε) and jumping (1250 µε) conditions. Trabecular and cortical parameters were determined by micro-CT, bone growth rate by calcein labeling and toluidine blue staining followed by histomorphometry. Bio-mechanical properties were evaluated from bending tests. HI group reduced rat body weight and food consumption compared to shams. Bone growth rate also decreased in MI and HI groups despite developing thicker hypertrophic and proliferative zone heights. HI group showed significant increment in bone mineral density, trabecular thickness, cortical and total surface area. Ultimate load and stiffness were also increased in MI and HI groups. We conclude that impact loading during adolescence reduces bone growth moderately but improves bone quality and biomechanics at the end of the growing period.
Highlights
A fundamental tenet of bone biomechanics is the adaptation phenomenon of bone microstructure under regularly applied mechanical loading[1,2]
We hypothesize that bone morphometry and biomechanics can be improved, but bone growth would remain unaffected under the controlled impact loading applied during the adolescence period
This study aimed to use an animal model to investigate the effects of well controlled in vivo low, medium and high impact loadings applied during puberty on bone growth, morphometry and biomechanics
Summary
A fundamental tenet of bone biomechanics is the adaptation phenomenon of bone microstructure under regularly applied mechanical loading[1,2]. Ground reaction forces, which generate stresses and strains on our weight-bearing bones, are determinant factors of bone remodeling. They are greater when we move faster and/or more intensively, vary according to the type of physical activities[6]. There are a few clinical and animal studies investigating the effects of impact loading on adolescent growth, but results are inconsistent. We hypothesize that bone morphometry and biomechanics can be improved, but bone growth would remain unaffected under the controlled impact loading applied during the adolescence period. This study aimed to use an animal model (rat tibia) to investigate the effects of well controlled in vivo low, medium and high impact loadings applied during puberty on bone growth, morphometry and biomechanics
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
