ArticleJournal of biomechanics2009
Six months of disuse during hibernation does not increase intracortical porosity or decrease cortical bone geometry, strength, or mineralization in black bear (Ursus americanus) femurs.
Article in Journal of biomechanics, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
21 citing papers in PubMed, 56 citations in OpenAlex.
- A review on ecological and physiological studies in bears from a One Health perspective.The Journal of veterinary medical science · 2025Review
- Hypothyroidism in hibernating brown bears.Thyroid research · 2023Article
- Differential bone remodeling mechanism in hindlimb unloaded rats and hibernating Daurian ground squirrels: a comparison between artificial and natural disuse.Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology · 2021Article
- Transcriptional changes and preservation of bone mass in hibernating black bears.Scientific reports · 2021Article
- Cardiomyocyte Protection by Hibernating Brown Bear Serum: Toward the Identification of New Protective Molecules Against Myocardial Infarction.Frontiers in cardiovascular medicine · 2021Article
- Shallow metabolic depression and human spaceflight: a feasible first step.Journal of applied physiology (Bethesda, Md. : 1985) · 2020Article
- Calcium homeostasis during hibernation and in mechanical environments disrupting calcium homeostasis.Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology · 2020Review
- Adult Stem Cells in Hibernation: Future Perspectives of Space Travel.International journal of stem cells · 2019Review
- Krogh's principle for musculoskeletal physiology and pathology.Journal of musculoskeletal & neuronal interactions · 2018Article
- Novel treatment strategies for chronic kidney disease: insights from the animal kingdom.Nature reviews. Nephrology · 2018Review
- Insights from the Den: How Hibernating Bears May Help Us Understand and Treat Human Disease.Clinical and translational science · 2015Review
- Suppressed bone remodeling in black bears conserves energy and bone mass during hibernation.The Journal of experimental biology · 2015Article
- Evidence for the adverse effect of starvation on bone quality: a review of the literature.International journal of endocrinology · 2015Review
- Endocrine regulation of bone and energy metabolism in hibernating mammals.Integrative and comparative biology · 2014Review
- Metabolic changes in summer active and anuric hibernating free-ranging brown bears (Ursus arctos).PloS one · 2013Article
- Serum immune-related proteins are differentially expressed during hibernation in the American black bear.PloS one · 2013Article
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- Thirteen-lined ground squirrels (Ictidomys tridecemlineatus) show microstructural bone loss during hibernation but preserve bone macrostructural geometry and strength.The Journal of experimental biology · 2011Article
- Vitamin D status and bone and connective tissue turnover in brown bears (Ursus arctos) during hibernation and the active state.PloS one · 2011Article
Corrections and comments
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Authors and funding
8 authors at 3 institutions in 1 country.
Funding
Abstract
Disuse typically uncouples bone formation from resorption, leading to bone loss which compromises bone mechanical properties and increases the risk of bone fracture. Previous studies suggest that bears can prevent bone loss during long periods of disuse (hibernation), but small sample sizes have limited the conclusions that can be drawn regarding the effects of hibernation on bone structure and strength in bears. Here we quantified the effects of hibernation on structural, mineral, and mechanical properties of black bear (Ursus americanus) cortical bone by studying femurs from large groups of male and female bears (with wide age ranges) killed during pre-hibernation (fall) and post-hibernation (spring) periods. Bone properties that are affected by body mass (e.g. bone geometrical properties) tended to be larger in male compared to female bears. There were no differences (p>0.226) in bone structure, mineral content, or mechanical properties between fall and spring bears. Bone geometrical properties differed by less than 5% and bone mechanical properties differed by less than 10% between fall and spring bears. Porosity (fall: 5.5+/-2.2%; spring: 4.8+/-1.6%) and ash fraction (fall: 0.694+/-0.011; spring: 0.696+/-0.010) also showed no change (p>0.304) between seasons. Statistical power was high (>72%) for these analyses. Furthermore, bone geometrical properties and ash fraction (a measure of mineral content) increased with age and porosity decreased with age. These results support the idea that bears possess a biological mechanism to prevent disuse and age-related osteoporoses.
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Registered trials
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