1
|
Maki N, Fujimoto K, Nakagawa R, Hashiba D, Arai H, Ohtori S. Impending Atypical Femoral Fracture on the Contralateral Side Progressed to a Complete Fracture Early after Surgery for an Atypical Femoral Fracture: A Case Report. J Orthop Case Rep 2024; 14:135-139. [PMID: 38911004 PMCID: PMC11189085 DOI: 10.13107/jocr.2024.v14.i06.4530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/21/2024] [Indexed: 06/25/2024] Open
Abstract
Introduction Long-term bisphosphonate (BP) administration may cause an atypical femoral fracture that is occasionally bilateral. We encountered a case of an impending atypical femoral fracture on the contralateral side that progressed to a complete fracture early after surgery for an atypical femoral fracture. Case Report An 83-year-old woman who had received long-term BP therapy developed a right femoral atypical incomplete fracture that progressed to a complete fracture 5 days after surgery for an atypical complete left femoral fracture. Conclusion The findings from this case suggest that when an atypical femoral fracture occurs in patients receiving long-term BP therapy, the possibility of an impending atypical femoral fracture on the contralateral side should be considered, and radiographs or CT images should be obtained for both legs. To prevent long-term bed rest in older adults, one- or two-stage bilateral surgery should be considered when imaging reveals bilateral atypical femoral fractures.
Collapse
Affiliation(s)
- Narumi Maki
- Department of Orthopaedic Surgery, Kohnodai Hospital, National Center for Global Health and Medicine, Chiba, Japan
| | - Kazuki Fujimoto
- Department of Orthopaedic Surgery, Kohnodai Hospital, National Center for Global Health and Medicine, Chiba, Japan
| | - Ryosuke Nakagawa
- Department of Orthopaedic Surgery, Kohnodai Hospital, National Center for Global Health and Medicine, Chiba, Japan
| | - Daisuke Hashiba
- Department of Orthopaedic Surgery, Kohnodai Hospital, National Center for Global Health and Medicine, Chiba, Japan
| | - Hajime Arai
- Department of Orthopaedic Surgery, Kohnodai Hospital, National Center for Global Health and Medicine, Chiba, Japan
| | - Seiji Ohtori
- Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan
| |
Collapse
|
2
|
Ning B, Londono I, Laporte C, Villemure I. Zoledronate reduces loading-induced microdamage in cortical ulna of ovariectomized rats. J Mech Behav Biomed Mater 2024; 150:106350. [PMID: 38171139 DOI: 10.1016/j.jmbbm.2023.106350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 12/22/2023] [Accepted: 12/24/2023] [Indexed: 01/05/2024]
Abstract
As a daily physiological mechanism in bone, microdamage accumulation dissipates energy and helps to prevent fractures. However, excessive damage accumulation might bring adverse effects to bone mechanical properties, which is especially problematic among the osteoporotic and osteopenic patients treated by bisphosphonates. Some pre-clinical studies in the literature applied forelimb loading models to produce well-controlled microdamage in cortical bone. Ovariectomized animals were also extensively studied to assimilate human conditions of estrogen-related bone loss. In the present study, we combined both experimental models to investigate microdamage accumulation in the context of osteopenia and zoledronate treatment. Three-month-old normal and ovariectomized rats treated by saline or zoledronate underwent controlled compressive loading on their right forelimb to create in vivo microdamage, which was then quantified by barium sulfate contrast-enhanced micro-CT imaging. Weekly in vivo micro-CT scans were taken to evaluate bone (re)modeling and to capture microstructural changes over time. After sacrifice, three-point-bending tests were performed to assess bone mechanical properties. Results show that the zoledronate treatment can reduce cortical microdamage accumulation in ovariectomized rats, which might be explained by the enhancement of several bone structural properties such as ultimate force, yield force, cortical bone area and volume. The rats showed increased bone formation volume and surface after the generation of microdamage, especially for the normal and the ovariectomized groups. Woven bone formation was also observed in loaded ulnae, which was most significant in ovariectomized rats. Although all the rats showed strong correlations between periosteal bone formation and microdamage accumulation, the correlation levels were lower for the zoledronate-treated groups, potentially because of their lower levels of microdamage. The present study provides insights to further investigations of pharmaceutical treatments for osteoporosis and osteopenia. The same experimental concept can be applied in future studies on microdamage and drug testing.
Collapse
Affiliation(s)
- Bohao Ning
- Department of Mechanical Engineering, Polytechnique Montréal, P.O. Box 6079, Station Centre-Ville, Montréal, QC, H3C 3A7, Canada; CHU Sainte-Justine Research Centre, 3175 Côte-Sainte-Catherine Road, Montréal, QC, H3T 1C5, Canada
| | - Irène Londono
- CHU Sainte-Justine Research Centre, 3175 Côte-Sainte-Catherine Road, Montréal, QC, H3T 1C5, Canada
| | - Catherine Laporte
- CHU Sainte-Justine Research Centre, 3175 Côte-Sainte-Catherine Road, Montréal, QC, H3T 1C5, Canada; Department of Electrical Engineering, École de Technologie Supérieure, 1100 Notre-Dame Street West, Montréal, QC, H3C 1K3, Canada
| | - Isabelle Villemure
- Department of Mechanical Engineering, Polytechnique Montréal, P.O. Box 6079, Station Centre-Ville, Montréal, QC, H3C 3A7, Canada; CHU Sainte-Justine Research Centre, 3175 Côte-Sainte-Catherine Road, Montréal, QC, H3T 1C5, Canada.
| |
Collapse
|
3
|
Xia C, Pu Y, Zhang Q, Hu Q, Wang Y. The feasibility of discriminating BRONJ lesion bone with Raman spectroscopy. Front Endocrinol (Lausanne) 2023; 14:1099889. [PMID: 37223036 PMCID: PMC10202174 DOI: 10.3389/fendo.2023.1099889] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 04/20/2023] [Indexed: 05/25/2023] Open
Abstract
Background With the frequent use of Bisphosphonates (BPs), the morbidity of BP-related osteonecrosis of the jaw (BRONJ) is also increasing. However, the prevention and treatment of BRONJ is faced with enormous challenges. This study aimed to illuminate the influence of BP administration in the rat mandible and explore the feasibility of discriminating BRONJ lesion bone with Raman spectroscopy. Materials and methods First, we explored the time- and mode-dependent effects of BP administration on the rat mandible with Raman spectroscopy. Second, the BRONJ rat model was constructed, and the lesion and healthy bone components were analyzed using Raman spectroscopy. Results When only BPs were administered, no rats showed BRONJ symptoms, and no difference could be found in the Raman spectra. However, when combined with local surgery, six (6/8) rats showed BRONJ symptoms. The Raman spectra also showed a significant difference between the lesion and healthy bone. Conclusion In the progression of BRONJ, BPs and local stimulation play an essential role. Both BPs administration and local stimulation need to be controlled to prevent BRONJ. Moreover, BRONJ lesion bone in rats could be discriminated with Raman spectroscopy. This novel method would become a complement in the treatment of BRONJ in the future.
Collapse
|
4
|
Haider IT, Loundagin LL, Sawatsky A, Kostenuik PJ, Boyd SK, Edwards WB. Twelve Months of Denosumab and/or Alendronate Is Associated With Improved Bone Fatigue Life, Microarchitecture, and Density in Ovariectomized Cynomolgus Monkeys. J Bone Miner Res 2023; 38:403-413. [PMID: 36533719 DOI: 10.1002/jbmr.4758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/25/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
Prolonged use of antiresorptives such as the bisphosphonate alendronate (ALN) and the RANKL inhibitor denosumab (DMAb) are associated with rare cases of atypical femoral fracture (AFF). The etiology of AFF is unclear, but it has been hypothesized that potent osteoclast inhibitors may reduce bone fatigue resistance. The purpose of this study was to quantify the relationship between antiresorptive treatment and fatigue life (cycles to failure) in bone from ovariectomized cynomolgus monkeys. We analyzed humeral bone from 30 animals across five treatment groups. Animals were treated for 12 months with subcutaneous (sc) vehicle (VEH), sc DMAb (25 mg/kg/month), or intravenous (iv) ALN (50 μg/kg/month). Another group received 6 months VEH followed by 6 months DMAb (VEH-DMAb), and the final group received 6 months ALN followed by 6 months DMAb (ALN-DMAb). A total of 240 cortical beam samples were cyclically tested in four-point bending at 80, 100, 120, or 140 MPa peak stress. High-resolution imaging and density measurements were performed to evaluate bone microstructure and composition. Samples from the ALN (p = 0.014), ALN-DMAb (p = 0.008), and DMAb (p < 0.001) groups illustrated higher fatigue-life measurements than VEH. For example, at 140 MPa the VEH group demonstrated a median ± interquartile range (IQR) fatigue life of 1987 ± 10593 cycles, while animals in the ALN, ALN-DMAb, and DMAb groups survived 9850 ± 13648 (+395% versus VEH), 10493 ± 16796 (+428%), and 14495 ± 49299 (+629%) cycles, respectively. All antiresorptive treatment groups demonstrated lower porosity, smaller pore size, greater pore spacing, and lower number of canals versus VEH (p < 0.001). Antiresorptive treatment was also associated with greater apparent density, dry density, and ash density (p ≤ 0.03). We did not detect detrimental changes following antiresorptive treatments that would explain their association with AFF. In contrast, 12 months of treatment may have a protective effect against fatigue fractures. © 2022 American Society for Bone and Mineral Research (ASBMR).
Collapse
Affiliation(s)
- Ifaz T Haider
- Human Performance Lab, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Lindsay L Loundagin
- Human Performance Lab, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, SK, Canada
| | - Andrew Sawatsky
- Human Performance Lab, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Paul J Kostenuik
- Phylon Pharma Services, Newbury Park, CA, USA.,School of Dentistry, University of Michigan (Adjunct), Ann Arbor, MI, USA
| | - Steven K Boyd
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - W Brent Edwards
- Human Performance Lab, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Biomedical Engineering, Schulich School of Engineering, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
5
|
Erbaş İM, İlgün Gürel D, Manav Kabayeğit Z, Koç A, Ünüvar T, Abacı A, Böber E, Anık A. Clinical, genetic characteristics and treatment outcomes of children and adolescents with osteogenesis imperfecta: a two-center experience. Connect Tissue Res 2022; 63:349-358. [PMID: 34107839 DOI: 10.1080/03008207.2021.1932853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Osteogenesis imperfecta (OI), is a heritable, heterogeneous connective tissue disorder, characterized by fragile bones. There are conflicting results about genotype-phenotype correlations and efficiency of bisphosphonate treatment in this disorder. AIM We aimed to evaluate the clinical, genetic characteristics, and long-term follow-up results of children and adolescents with OI. MATERIALS AND METHODS A two-center retrospective study was conducted using demographic, clinical, and genetic data obtained from the medical records of the patients. RESULTS Twenty-nine patients (62% male, median age; 3.6 years) with OI diagnosis from 26 families were included in the study. Thirteen different variants (nine were novel) were described in 16 patients in COL1A1, COL1A2, and P3H1 genes. Our siblings with homozygous P3H1 variants had a severe phenotype with intrauterine and neonatal fractures. Twenty-two patients were treated with bisphosphonates (17 of them with pamidronate, five with alendronate) with a median duration of 3.0 (1.6-4.8) years. Eleven patients (50%) suffered from fractures after the treatment. Haploinsufficiency variants in COL1A1 caused a milder skeletal phenotype with less fracture count and better treatment outcomes than structural variants. When compared with the anthropometric measurements at the initial diagnosis time, height Z-scores were lower on the last clinical follow-up (p = 0.009). CONCLUSIONS We could not find an obvious genotype-phenotype correlation in Turkish OI patients with COL1A1 or COL1A2 variants. Treatment with pamidronate was effective in reducing fracture counts, without any long-term adverse effects.
Collapse
Affiliation(s)
- İbrahim Mert Erbaş
- Division of Pediatric Endocrinology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Deniz İlgün Gürel
- Department of Pediatrics, Faculty of Medicine, Aydın Adnan Menderes University, Aydın, Turkey
| | - Zehra Manav Kabayeğit
- Department of Medical Genetics, Faculty of Medicine, Aydın Adnan Menderes University, Aydın, Turkey
| | - Altuğ Koç
- Department of Medical Genetics, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Tolga Ünüvar
- Division of Pediatric Endocrinology, Faculty of Medicine, Aydın Adnan Menderes University, Aydın, Turkey
| | - Ayhan Abacı
- Division of Pediatric Endocrinology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Ece Böber
- Division of Pediatric Endocrinology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Ahmet Anık
- Division of Pediatric Endocrinology, Faculty of Medicine, Aydın Adnan Menderes University, Aydın, Turkey
| |
Collapse
|
6
|
Xuan Y, Wang J, Zhang X, Wang J, Li J, Liu Q, Lu G, Xiao M, Gao T, Guo Y, Cao C, Chen O, Wang K, Tang Y, Gu J. Resveratrol Attenuates High Glucose-Induced Osteoblast Dysfunction via AKT/GSK3β/FYN-Mediated NRF2 Activation. Front Pharmacol 2022; 13:862618. [PMID: 35677434 PMCID: PMC9169221 DOI: 10.3389/fphar.2022.862618] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 03/29/2022] [Indexed: 11/13/2022] Open
Abstract
Osteoblast dysfunction, induced by high glucose (HG), negatively impacts bone homeostasis and contributes to the pathology of diabetic osteoporosis (DOP). One of the most widely recognized mechanisms for osteoblast dysfunction is oxidative stress. Resveratrol (RES) is a bioactive antioxidant compound to combat oxidative damage. However, its role in the protection of HG-induced osteoblast dysfunction has not been clarified. Therefore, our study aimed to explore potential regulatory mechanisms of RES for attenuating HG-induced osteoblast dysfunction. Our results showed that osteoblast dysfunction under HG condition was significantly ameliorated by RES via the activation of nuclear factor erythroid 2-related factor (NRF2) to suppress oxidative stress. Furthermore, using Nrf2-shRNA and wortmannin, we identified that activation of NRF2 via RES was regulated by the AKT/glycogen synthase kinase 3β (GSK3β)/FYN axis.
Collapse
Affiliation(s)
- Yue Xuan
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Jie Wang
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Xiaohui Zhang
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Jie Wang
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Jiahao Li
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Qingbo Liu
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Guangping Lu
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Mengjie Xiao
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ting Gao
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yuanfang Guo
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Cong Cao
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ou Chen
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Kunli Wang
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yufeng Tang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Shandong First Medical University, Jinan, China
| | - Junlian Gu
- School of Nursing and Rehabilitation, Cheeloo College of Medicine, Shandong University, Jinan, China
| |
Collapse
|
7
|
Jeddi S, Yousefzadeh N, Kashfi K, Ghasemi A. Role of nitric oxide in type 1 diabetes-induced osteoporosis. Biochem Pharmacol 2021; 197:114888. [PMID: 34968494 DOI: 10.1016/j.bcp.2021.114888] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/09/2021] [Accepted: 12/09/2021] [Indexed: 12/18/2022]
Abstract
Type 1 diabetes (T1D)-induced osteoporosis is characterized by decreased bone mineral density, bone quality, rate of bone healing, bone formation, and increased bone resorption. Patients with T1D have a 2-7-fold higher risk of osteoporotic fracture. The mechanisms leading to increased risk of osteoporotic fracture in T1D include insulin deficiency, hyperglycemia, insulin resistance, lower insulin-like growth factor-1, hyperglycemia-induced oxidative stress, and inflammation. In addition, a higher probability of falling, kidney dysfunction, weakened vision, and neuropathy indirectly increase the risk of osteoporotic fracture in T1D patients. Decreased nitric oxide (NO) bioavailability contributes to the pathophysiology of T1D-induced osteoporotic fracture. This review discusses the role of NO in osteoblast-mediated bone formation and osteoclast-mediated bone resorption in T1D. In addition, the mechanisms involved in reduced NO bioavailability and activity in type 1 diabetic bones as well as NO-based therapy for T1D-induced osteoporosis are summarized. Available data indicates that lower NO bioavailability in diabetic bones is due to disruption of phosphatidylinositol 3‑kinase/protein kinase B/endothelial NO synthases and NO/cyclic guanosine monophosphate/protein kinase G signaling pathways. Thus, NO bioavailability may be boosted directly or indirectly by NO donors. As NO donors with NO-like effects in the bone, inorganic nitrate and nitrite can potentially be used as novel therapeutic agents for T1D-induced osteoporosis. Inorganic nitrites and nitrates can decrease the risk for osteoporotic fracture probably directly by decreasing osteoclast activity, decreasing fat accumulation in the marrow cavity, increasing osteoblast activity, and increasing bone perfusion or indirectly, by improving hyperglycemia, insulin resistance, and reducing body weight.
Collapse
Affiliation(s)
- Sajad Jeddi
- Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Nasibeh Yousefzadeh
- Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Khosrow Kashfi
- Department of Molecular, Cellular, and Biomedical Sciences, Sophie Davis School of Biomedical Education, City University of New York School of Medicine, NY, USA.
| | - Asghar Ghasemi
- Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
8
|
Yousefzadeh N, Jeddi S, Kashfi K, Ghasemi A. Diabetoporosis: Role of nitric oxide. EXCLI JOURNAL 2021; 20:764-780. [PMID: 34121973 PMCID: PMC8192884 DOI: 10.17179/excli2021-3541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 03/31/2021] [Indexed: 11/29/2022]
Abstract
Diabetoporosis, diabetic-related decreased bone quality and quantity, is one of the leading causes of osteoporotic fractures in subjects with type 2 diabetes (T2D). This is associated with lower trabecular and cortical bone quality, lower bone turnover rates, lower rates of bone healing, and abnormal posttranslational modifications of collagen. Decreased nitric oxide (NO) bioavailability has been reported within the bones of T2D patients and can be considered as one of the primary mechanisms by which diabetoporosis is manifested. NO donors increase trabecular and cortical bone quality, increase the rate of bone formation, accelerate the bone healing process, delay osteoporosis, and decrease osteoporotic fractures in T2D patients, suggesting the potential therapeutic implication of NO-based interventions. NO is produced in the osteoblast and osteoclast cells by three isoforms of NO synthase (NOS) enzymes. In this review, the roles of NO in bone remodeling in the normal and diabetic states are discussed. Also, the favorable effects of low physiological levels of NO produced by endothelial NOS (eNOS) versus detrimental effects of high pathological levels of NO produced by inducible NOS (iNOS) in diabetoporosis are summarized. Available data indicates decreased bone NO bioavailability in T2D and decreased expression of eNOS, and increased expression and activity of iNOS. NO donors can be considered novel therapeutic agents in diabetoporosis.
Collapse
Affiliation(s)
- Nasibeh Yousefzadeh
- Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sajad Jeddi
- Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Khosrow Kashfi
- Department of Molecular, Cellular, and Biomedical Sciences, Sophie Davis School of Biomedical Education, City University of New York School of Medicine, NY, USA
- PhD Program in Biology, City University of New York Graduate Center, New York,NY, USA
| | - Asghar Ghasemi
- Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
9
|
Burr DB. Fifty years of bisphosphonates: What are their mechanical effects on bone? Bone 2020; 138:115518. [PMID: 32622873 DOI: 10.1016/j.bone.2020.115518] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/26/2020] [Accepted: 06/30/2020] [Indexed: 12/12/2022]
Abstract
After fifty years of experience with several generations of bisphosphonates (BPs), and 25 years after these drugs were approved for use in humans, their mechanical effects on bone are still not fully understood. Certainly, these drugs have transformed the treatment of osteoporosis in both men and women. There is no question that they do prevent fractures related to low bone mass, and there is widespread agreement that they increase strength and stiffness of the vertebrae. There is less consensus, however, about their effects on cortical bone, or on bone tissue properties in either trabecular or cortical bone, or their effects with longer periods of treatment. The consensus of most studies, both those based on ovariectomized and intact animal models and on testing of human bone, is that long-term treatment and/or high doses with certain BPs make the bone tissue more brittle and less tough. This translates into reduced energy to fracture and potentially a shorter bone fatigue life. Many studies have been done, but Interpretation of the results of these studies is complicated by variations in which BP is used, the animal model used, dose, duration, and methods of testing. Duration effects and effects on impact properties of bone are gaps that should be filled with additional testing.
Collapse
Affiliation(s)
- David B Burr
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, United States of America; Department of Biomedical Engineering, Indiana University-Purdue University, Indianapolis, Indianapolis, IN 46202, United States of America.
| |
Collapse
|
10
|
Haider IT, Schneider PS, Edwards WB. The Role of Lower-Limb Geometry in the Pathophysiology of Atypical Femoral Fracture. Curr Osteoporos Rep 2019; 17:281-290. [PMID: 31410718 DOI: 10.1007/s11914-019-00525-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSEOF REVIEW The etiology of atypical femoral fracture (AFF) is likely multifactorial. In this review, we examined the recent literature investigating the role of lower-limb geometry in the pathophysiology of AFF. RECENT FINDINGS Increased femoral bowing was associated with prevalent AFF and a greater likelihood of a diaphyseal versus a subtrochanteric AFF location. Femoral neck geometry or hip alignment may also be related to AFF, but findings remain equivocal. Differences in femoral geometry may, in part, be responsible for the high rate of AFF in Asian compared with Caucasian populations. Finally, simulation studies suggest that lower-limb geometry influences AFF risk via its effects on mechanical strain of the lateral femoral cortex. Femoral geometry, and bowing in particular, is related to prevalent AFF, but more prospective investigation is needed to determine whether measurements of geometry can be used for clinical risk stratification.
Collapse
Affiliation(s)
- Ifaz T Haider
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, KNB 418, 2500 University Dr. NW, Calgary, Alberta, T2N 1N4, Canada
- McCaig Institute for Bone and Joint Health, University of Calgary, HRIC 3A08, 3280 Hospital Drive NW, Calgary, Alberta, T2N 4Z6, Canada
| | - Prism S Schneider
- McCaig Institute for Bone and Joint Health, University of Calgary, HRIC 3A08, 3280 Hospital Drive NW, Calgary, Alberta, T2N 4Z6, Canada
- Department of Surgery; Department of Community Health Sciences, Cumming School of Medicine, Foothills Campus, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
| | - W Brent Edwards
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, KNB 418, 2500 University Dr. NW, Calgary, Alberta, T2N 1N4, Canada.
- McCaig Institute for Bone and Joint Health, University of Calgary, HRIC 3A08, 3280 Hospital Drive NW, Calgary, Alberta, T2N 4Z6, Canada.
| |
Collapse
|
11
|
Mohsin S, Baniyas MM, AlDarmaki RS, Tekes K, Kalász H, Adeghate EA. An update on therapies for the treatment of diabetes-induced osteoporosis. Expert Opin Biol Ther 2019; 19:937-948. [PMID: 31079501 DOI: 10.1080/14712598.2019.1618266] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: Currently, 424 million people aged between 20 and 79 years worldwide are diabetic. More than 25% of adults aged over 65 years in North America have Type 2 diabetes mellitus (DM). Diabetes-induced osteoporosis (DM-OS) is caused by chronic hyperglycemia, advanced glycated end products and oxidative stress. The increase in the prevalence of DM-OS has prompted researchers to develop new biological therapies for the management of DM-OS. Areas covered: This review covered the current and novel biological agents used in the management of DM-OS. Data were retrieved from PubMed, Scopus, American Diabetes Association and International Osteoporosis Foundation websites, and ClinicalTrials.gov. The keywords for the search included: DM, osteoporosis, and management. Expert opinion: Several biological molecules have been examined in order to find efficient drugs for the treatment of DM-OS. These biological agents include anti-osteoporosis drugs: net anabolics (parathyroid hormone/analogs, androgens, calcilytics, anti-sclerostin antibody), net anti-resorptive osteoporosis drugs (calcitonin, estrogen, selective estrogen receptor modulators, bisphosphonates, RANKL antibody) and anti-diabetic drugs (alpha glucosidase inhibitors, sulfonylureas, biguanides, meglitinides, thiazolidinediones, GLP-1 receptor agonists, dipeptidylpeptidase-4 inhibitors, sodium glucose co-transporter-2 inhibitors, insulin). Biological medications that effectively decrease hyperglycemia and, at the same time, maintain bone health would be an ideal drug/drug combination for the treatment of DM-OS.
Collapse
Affiliation(s)
- Sahar Mohsin
- a Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University , Al Ain , United Arab Emirates
| | - May Myh Baniyas
- a Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University , Al Ain , United Arab Emirates
| | - Reem Smh AlDarmaki
- a Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University , Al Ain , United Arab Emirates
| | - Kornélia Tekes
- b Department of Pharmacodynamics, Faculty of Pharmacy, Semmelweis University , Budapest , Hungary
| | - Huba Kalász
- c Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University , Budapest , Hungary
| | - Ernest A Adeghate
- a Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University , Al Ain , United Arab Emirates
| |
Collapse
|
12
|
Buitendijk SKC, van de Laarschot DM, Smits AAA, Koromani F, Rivadeneira F, Beck TJ, Zillikens MC. Trabecular Bone Score and Hip Structural Analysis in Patients With Atypical Femur Fractures. J Clin Densitom 2019; 22:257-265. [PMID: 29661684 DOI: 10.1016/j.jocd.2018.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 03/13/2018] [Indexed: 01/03/2023]
Abstract
Bisphosphonate use has declined dramatically in recent years, partly because of fear of rare side effects like atypical femur fractures (AFFs). It is therefore desirable to have a diagnostic method to identify those at risk of AFF to prevent this serious complication. We compared trabecular microarchitecture and hip geometry between 30 patients with AFF and 141 controls of similar age and sex, using bisphosphonates. Trabecular bone score (TBS) and hip structural analysis (HSA) were used to assess trabecular microarchitecture and macroscopic hip geometry from dual-energy X-ray absorptiometry images of the lumbar spine and hip, respectively. General characteristics, TBS, and HSA were compared between patients with AFF and controls using Student's t tests and chi-square statistics. Associations between AFF and TBS and femur geometric characteristics by HSA were adjusted for sex, age, height, weight, ethnicity, duration of bisphosphonate use, and glucocorticoid use. Additionally, the analysis of TBS was adjusted for lumbar spine bone mineral density and the time difference between dual-energy X-ray absorptiometry scanning and the diagnosis of AFF. Patients with AFF had significantly higher body mass index than controls, had used bisphosphonates longer, and glucocorticoids and proton pump inhibitors more frequently. Sex-specific T-score was significantly higher in patients with AFF at the lumbar spine (p = 0.004), but not at the femoral neck (p = 0.190) after adjustment for age, height, and weight. TBS did not differ significantly between patients with AFF and controls. Neither neck shaft angle nor any geometric variables at the femoral shaft measured by HSA differed between patients with AFF and controls. At the narrow neck, patients with AFF had lower buckling ratio and higher centroid position, consistent with a lower risk of classical fragility hip fractures. The findings at narrow neck and higher bone mineral density might be explained by the fact that the majority of patients with AFF used bisphosphonates to prevent glucocorticoid-induced osteoporosis. Based on our results, TBS and HSA do not appear to have value in detecting patients at risk of AFF.
Collapse
Affiliation(s)
- Sanne K C Buitendijk
- Bone Center, Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
| | | | - Alexandra A A Smits
- Bone Center, Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Fjorda Koromani
- Bone Center, Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; Department of Epidemiology, Erasmus MC, Rotterdam, The Netherlands
| | - Fernando Rivadeneira
- Bone Center, Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; Department of Epidemiology, Erasmus MC, Rotterdam, The Netherlands
| | | | - M Carola Zillikens
- Bone Center, Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands.
| |
Collapse
|
13
|
Hunckler MD, Chu ED, Baumann AP, Curtis TE, Ravosa MJ, Allen MR, Roeder RK. The fracture toughness of small animal cortical bone measured using arc-shaped tension specimens: Effects of bisphosphonate and deproteinization treatments. Bone 2017; 105:67-74. [PMID: 28826844 DOI: 10.1016/j.bone.2017.08.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/17/2017] [Accepted: 08/17/2017] [Indexed: 01/22/2023]
Abstract
Small animal models, and especially transgenic models, have become widespread in the study of bone mechanobiology and metabolic bone disease, but test methods for measuring fracture toughness on multiple replicates or at multiple locations within a single small animal bone are lacking. Therefore, the objective of this study was to develop a method to measure cortical bone fracture toughness in multiple specimens and locations along the diaphysis of small animal bones. Arc-shaped tension specimens were prepared from the mid-diaphysis of rabbit ulnae and loaded to failure to measure the radial fracture toughness in multiple replicates per bone. The test specimen dimensions, crack length, and maximum load met requirements for measuring the plane strain fracture toughness. Experimental groups included a control group, bisphosphonate treatment group, and an ex vivo deproteinization treatment following bisphosphonate treatment (5 rabbits/group and 15 specimens/group). The fracture toughness of ulnar cortical bone from rabbits treated with zoledronic acid for six months exhibited no difference compared with the control group. Partially deproteinized specimens exhibited significantly lower fracture toughness compared with both the control and bisphosphonate treatment groups. The deproteinization treatment increased tissue mineral density (TMD) and resulted in a negative linear correlation between the measured fracture toughness and TMD. Fracture toughness measurements were repeatable with a coefficient of variation of 12-16% within experimental groups. Retrospective power analysis of the control and deproteinization treatment groups indicated a minimum detectable difference of 0.1MPa·m1/2. Therefore, the overall results of this study suggest that arc-shaped tension specimens offer an advantageous new method for measuring the fracture toughness in small animal bones.
Collapse
Affiliation(s)
- Michael D Hunckler
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Ethan D Chu
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Andrew P Baumann
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Tyler E Curtis
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Matthew J Ravosa
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA; Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Matthew R Allen
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Ryan K Roeder
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA.
| |
Collapse
|
14
|
Jin A, Cobb J, Hansen U, Bhattacharya R, Reinhard C, Vo N, Atwood R, Li J, Karunaratne A, Wiles C, Abel R. The effect of long-term bisphosphonate therapy on trabecular bone strength and microcrack density. Bone Joint Res 2017; 6:602-609. [PMID: 29066534 PMCID: PMC5670367 DOI: 10.1302/2046-3758.610.bjr-2016-0321.r1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Objectives Bisphosphonates (BP) are the first-line treatment for preventing fragility fractures. However, concern regarding their efficacy is growing because bisphosphonate is associated with over-suppression of remodelling and accumulation of microcracks. While dual-energy X-ray absorptiometry (DXA) scanning may show a gain in bone density, the impact of this class of drug on mechanical properties remains unclear. We therefore sought to quantify the mechanical strength of bone treated with BP (oral alendronate), and correlate data with the microarchitecture and density of microcracks in comparison with untreated controls. Methods Trabecular bone from hip fracture patients treated with BP (n = 10) was compared with naïve fractured (n = 14) and non-fractured controls (n = 6). Trabecular cores were synchrotron scanned and micro-CT scanned for microstructural analysis, including quantification of bone volume fraction, microarchitecture and microcracks. The specimens were then mechanically tested in compression. Results BP bone was 28% lower in strength than untreated hip fracture bone, and 48% lower in strength than non-fractured control bone (4.6 MPa vs 6.4 MPa vs 8.9 MPa). BP-treated bone had 24% more microcracks than naïve fractured bone and 51% more than non-fractured control (8.12/cm2vs 6.55/cm2vs 5.25/cm2). BP and naïve fracture bone exhibited similar trabecular microarchitecture, with significantly lower bone volume fraction and connectivity than non-fractured controls. Conclusion BP therapy had no detectable mechanical benefit in the specimens examined. Instead, its use was associated with substantially reduced bone strength. This low strength may be due to the greater accumulation of microcracks and a lack of any discernible improvement in bone volume or microarchitecture. This preliminary study suggests that the clinical impact of BP-induced microcrack accumulation may be significant. Cite this article: A. Jin, J. Cobb, U. Hansen, R. Bhattacharya, C. Reinhard, N. Vo, R. Atwood, J. Li, A. Karunaratne, C. Wiles, R. Abel. The effect of long-term bisphosphonate therapy on trabecular bone strength and microcrack density. Bone Joint Res 2017;6:602–609. DOI: 10.1302/2046-3758.610.BJR-2016-0321.R1.
Collapse
Affiliation(s)
- A Jin
- Department of Mechanical Engineering, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - J Cobb
- Imperial College London, Charing Cross Hospital, Fulham Palace Road, London W6 8RF, UK
| | - U Hansen
- Department of Mechanical Engineering, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - R Bhattacharya
- Musculoskeletal Sciences, Surgery and Cancer, Imperial College London, Charing Cross Hospital, 7L21, East Lab Block MSk Lab, Margravine Road, London W6 8RP, UK
| | - C Reinhard
- Diamond Light Source Ltd, Fermi Avenue, Didcot OX11 0DE, Oxfordshire, UK
| | - N Vo
- Diamond Light Source Ltd, Fermi Avenue, Didcot OX11 0DE, Oxfordshire, UK
| | - R Atwood
- Diamond Light Source Ltd, Fermi Avenue, Didcot OX11 0DE, Oxfordshire, UK
| | - J Li
- Department of Mechanical Engineering, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - A Karunaratne
- Bioengineering, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - C Wiles
- Musculoskeletal Sciences, Surgery and Cancer, Imperial College London, Charing Cross Hospital, 7L21, East Lab Block MSk Lab, Margravine Road, London W6 8RP, UK
| | - R Abel
- Musculoskeletal Sciences, Surgery and Cancer, Imperial College London, Charing Cross Hospital, 7L21, East Lab Block MSk Lab, Margravine Road, London W6 8RP, UK
| |
Collapse
|
15
|
Allen MR. Preclinical Models for Skeletal Research: How Commonly Used Species Mimic (or Don’t) Aspects of Human Bone. Toxicol Pathol 2017; 45:851-854. [DOI: 10.1177/0192623317733925] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Preclinical studies play an indispensable role in exploring the biological regulation of the musculoskeletal system. They are required in all drug development pipelines where both small and large animal models are needed to understand efficacy and side effects. This brief review highlights 4 aspects of human bone, longitudinal bone growth, intracortical remodeling, collagen/mineral interface, and age-related changes, and discusses how various animal models recapitulate (or don’t) these aspects of human skeletal physiology.
Collapse
Affiliation(s)
- Matthew R. Allen
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, Indiana, USA
| |
Collapse
|
16
|
Shao Y, Hernandez-Buquer S, Childress P, Stayrook KR, Alvarez MB, Davis H, Plotkin LI, He Y, Condon KW, Burr DB, Warden SJ, Robling AG, Yang FC, Wek RC, Allen MR, Bidwell JP. Improving Combination Osteoporosis Therapy in a Preclinical Model of Heightened Osteoanabolism. Endocrinology 2017; 158:2722-2740. [PMID: 28637206 PMCID: PMC5659666 DOI: 10.1210/en.2017-00355] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/15/2017] [Indexed: 11/19/2022]
Abstract
Combining anticatabolic agents with parathyroid hormone (PTH) to enhance bone mass has yielded mixed results in osteoporosis patients. Toward the goal of enhancing the efficacy of these regimens, we tested their utility in combination with loss of the transcription factor Nmp4 because disabling this gene amplifies PTH-induced increases in trabecular bone in mice by boosting osteoblast secretory activity. We addressed whether combining a sustained anabolic response with an anticatabolic results in superior bone acquisition compared with PTH monotherapy. Additionally, we inquired whether Nmp4 interferes with anticatabolic efficacy. Wild-type and Nmp4-/- mice were ovariectomized at 12 weeks of age, followed by therapy regimens, administered from 16 to 24 weeks, and included individually or combined PTH, alendronate (ALN), zoledronate (ZOL), and raloxifene (RAL). Anabolic therapeutic efficacy generally corresponded with PTH + RAL = PTH + ZOL > PTH + ALN = PTH > vehicle control. Loss of Nmp4 enhanced femoral trabecular bone increases under PTH + RAL and PTH + ZOL. RAL and ZOL promoted bone restoration, but unexpectedly, loss of Nmp4 boosted RAL-induced increases in femoral trabecular bone. The combination of PTH, RAL, and loss of Nmp4 significantly increased bone marrow osteoprogenitor number, but did not affect adipogenesis or osteoclastogenesis. RAL, but not ZOL, increased osteoprogenitors in both genotypes. Nmp4 status did not influence bone serum marker responses to treatments, but Nmp4-/- mice as a group showed elevated levels of the bone formation marker osteocalcin. We conclude that the heightened osteoanabolism of the Nmp4-/- skeleton enhances the effectiveness of diverse osteoporosis treatments, in part by increasing hyperanabolic osteoprogenitors. Nmp4 provides a promising target pathway for identifying barriers to pharmacologically induced bone formation.
Collapse
Affiliation(s)
- Yu Shao
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Selene Hernandez-Buquer
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Paul Childress
- Department of Orthopedic Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Keith R. Stayrook
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Marta B. Alvarez
- Department of Orthopedic Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Hannah Davis
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Lilian I. Plotkin
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Yongzheng He
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana 46202
- Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Keith W. Condon
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - David B. Burr
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Stuart J. Warden
- Center for Translational Musculoskeletal Research, School of Health and Rehabilitation Sciences, Indiana University, Indianapolis, Indiana 46202
- Department of Physical Therapy, School of Health and Rehabilitation Sciences, Indiana University, Indianapolis, Indiana 46202
| | - Alexander G. Robling
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Feng-Chun Yang
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Ronald C. Wek
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Matthew R. Allen
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
- Richard A. Roudebush Veterans Administration Medical Center, Indianapolis, Indiana 46202
| | - Joseph P. Bidwell
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| |
Collapse
|
17
|
Allen MR, McNerny E, Aref M, Organ JM, Newman CL, McGowan B, Jang T, Burr DB, Brown DM, Hammond M, Territo PR, Lin C, Persohn S, Jiang L, Riley AA, McCarthy BP, Hutchins GD, Wallace JM. Effects of combination treatment with alendronate and raloxifene on skeletal properties in a beagle dog model. PLoS One 2017; 12:e0181750. [PMID: 28793321 PMCID: PMC5549927 DOI: 10.1371/journal.pone.0181750] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 07/06/2017] [Indexed: 12/18/2022] Open
Abstract
A growing number of studies have investigated combination treatment as an approach to treat bone disease. The goal of this study was to investigate the combination of alendronate and raloxifene with a particular focus on mechanical properties. To achieve this goal we utilized a large animal model, the beagle dog, used previously by our laboratory to study both alendronate and raloxifene monotherapies. Forty-eight skeletally mature female beagles (1–2 years old) received daily oral treatment: saline vehicle (VEH), alendronate (ALN), raloxifene (RAL) or both ALN and RAL. After 6 and 12 months of treatment, all animals underwent assessment of bone material properties using in vivo reference point indentation (RPI) and skeletal hydration using ultra-short echo magnetic resonance imaging (UTE-MRI). End point measures include imaging, histomorphometry, and mechanical properties. Bone formation rate was significantly lower in iliac crest trabecular bone of animals treated with ALN (-71%) and ALN+RAL (-81%) compared to VEH. In vivo assessment of properties by RPI yielded minimal differences between groups while UTE-MRI showed a RAL and RAL+ALN treatment regimens resulted in significantly higher bound water compared to VEH (+23 and +18%, respectively). There was no significant difference among groups for DXA- or CT-based measures lumbar vertebra, or femoral diaphysis. Ribs of RAL-treated animals were smaller and less dense compared to VEH and although mechanical properties were lower the material-level properties were equivalent to normal. In conclusion, we present a suite of data in a beagle dog model treated for one year with clinically-relevant doses of alendronate and raloxifene monotherapies or combination treatment with both agents. Despite the expected effects on bone remodeling, our study did not find the expected benefit of ALN to BMD or structural mechanical properties, and thus the viability of the combination therapy remains unclear.
Collapse
Affiliation(s)
- Matthew R. Allen
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Orthopedics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, Indiana, United States of America
- * E-mail:
| | - Erin McNerny
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Mohammad Aref
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Jason M. Organ
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, Indiana, United States of America
| | - Christopher L. Newman
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Brian McGowan
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Tim Jang
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - David B. Burr
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Orthopedics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, Indiana, United States of America
| | - Drew M. Brown
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Max Hammond
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, Indiana, United States of America
| | - Paul R. Territo
- Department of Radiology and Imaging Sciences Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Chen Lin
- Department of Radiology and Imaging Sciences Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Scott Persohn
- Department of Radiology and Imaging Sciences Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Lei Jiang
- Department of Radiology and Imaging Sciences Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Amanda A. Riley
- Department of Radiology and Imaging Sciences Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Brian P. McCarthy
- Department of Radiology and Imaging Sciences Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Gary D. Hutchins
- Department of Radiology and Imaging Sciences Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Joseph M. Wallace
- Department of Orthopedics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, Indiana, United States of America
| |
Collapse
|
18
|
Bögl HP, Aspenberg P, Schilcher J. Undisturbed local bone formation capacity in patients with atypical femoral fractures: a case series. Osteoporos Int 2017; 28:2439-2444. [PMID: 28474166 DOI: 10.1007/s00198-017-4058-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 04/12/2017] [Indexed: 01/13/2023]
Abstract
UNLABELLED We excised the fracture site in 8 patients with incomplete atypical femoral fractures by drilling an 11-mm-diameter hole. New bone formation could be seen in the hole within a normal time frame. Delayed healing of these fractures might be unrelated to an impaired capacity to form bone. INTRODUCTION Incomplete atypical femoral fractures (undisplaced cracks) heal slowly or not at all, and often progress to a complete fracture with minimal trauma. The impaired healing has been attributed to an impaired biologic healing capacity related to bisphosphonate use, or, alternatively, to the mechanical environment within the fracture crack. This study aimed to investigate the capacity for bone formation after resection of the fracture site. METHODS Between 2008 and 2014, we recruited eight patients with incomplete atypical femoral fractures. All used oral bisphosphonates before the fracture for on average 8 years (range 4 to 15) and complained of thigh pain. The fractures were stabilized with reamed cephalomedullary nails. During surgery, the fracture site in the lateral cortex was resected with a cylindrical drill (diameter 11.5 mm). The cylindrical cortical defect allowed radiographic evaluation of new bone formation, and the patients were followed clinically and radiologically for 24 months (range 15 to 92). RESULTS After 3 months, newly formed bone could be seen in the cortical defects in all patients. After 13-26 months, the previous defects showed continuous cortical bone. At final follow-up, all patients reported full recovery of pre-surgical complaints. No complications occurred and no reoperations were performed. CONCLUSIONS New bone formation occurred within a time frame that appears normal for healing of cortical bone defects. This suggests that the capacity to form new bone is intact.
Collapse
Affiliation(s)
- H P Bögl
- Department of Experimental and Clinical Medicine, Faculty of Health Science, Linköping University, SE-581 85, Linköping, Sweden
| | - P Aspenberg
- Department of Experimental and Clinical Medicine, Faculty of Health Science, Linköping University, SE-581 85, Linköping, Sweden
| | - J Schilcher
- Department of Orthopedic Surgery, Gävle hospital, SE-80 324, Gävle, Sweden.
| |
Collapse
|
19
|
Meixner CN, Aref MW, Gupta A, McNerny EMB, Brown D, Wallace JM, Allen MR. Raloxifene Improves Bone Mechanical Properties in Mice Previously Treated with Zoledronate. Calcif Tissue Int 2017; 101:75-81. [PMID: 28246928 PMCID: PMC5459622 DOI: 10.1007/s00223-017-0257-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 02/16/2017] [Indexed: 12/18/2022]
Abstract
Bisphosphonates represent the gold-standard pharmaceutical agent for reducing fracture risk. Long-term treatment with bisphosphonates can result in tissue brittleness which in rare clinical cases manifests as atypical femoral fracture. Although this has led to an increasing call for bisphosphonate cessation, few studies have investigated therapeutic options for follow-up treatment. The goal of this study was to test the hypothesis that treatment with raloxifene, a drug that has cell-independent effects on bone mechanical material properties, could reverse the compromised mechanical properties that occur following zoledronate treatment. Skeletally mature male C57Bl/6J mice were treated with vehicle (VEH), zoledronate (ZOL), or ZOL followed by raloxifene (RAL; 2 different doses). At the conclusion of 8 weeks of treatment, femora were collected and assessed with microCT and mechanical testing. Trabecular BV/TV was significantly higher in all treated animals compared to VEH with both RAL groups having significantly higher BV/TV compared to ZOL (+21%). All three drug-treated groups had significantly more cortical bone area, higher cortical thickness, and greater moment of inertia at the femoral mid-diaphysis compared to VEH with no difference among the three treated groups. All three drug-treated groups had significantly higher ultimate load compared to VEH-treated animals (+14 to 18%). Both doses of RAL resulted in significantly higher displacement values compared to ZOL-treated animals (+25 to +50%). In conclusion, the current work shows beneficial effects of raloxifene in animals previously treated with zoledronate. The higher mechanical properties of raloxifene-treated animals, combined with similar cortical bone geometry compared to animals treated with zoledronate, suggest that the raloxifene treatment is enhancing mechanical material properties of the tissue.
Collapse
Affiliation(s)
- Cory N Meixner
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, MS 5035, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - Mohammad W Aref
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, MS 5035, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - Aryaman Gupta
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, MS 5035, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - Erin M B McNerny
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, MS 5035, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - Drew Brown
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, MS 5035, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - Joseph M Wallace
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, IN, USA
| | - Matthew R Allen
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, MS 5035, 635 Barnhill Dr., Indianapolis, IN, 46202, USA.
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.
- Department of Biomedical Engineering, Indiana University Purdue University of Indianapolis, Indianapolis, IN, USA.
- Roudebush Veterans Administration Medical Center, Indianapolis, IN, USA.
| |
Collapse
|
20
|
Role of cortical bone in hip fracture. BONEKEY REPORTS 2017; 6:867. [PMID: 28277562 DOI: 10.1038/bonekey.2016.82] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 09/03/2016] [Indexed: 12/23/2022]
Abstract
In this review, I consider the varied mechanisms in cortical bone that help preserve its integrity and how they deteriorate with aging. Aging affects cortical bone in two ways: extrinsically through its effects on the individual that modify its mechanical loading experience and 'milieu interieur'; and intrinsically through the prolonged cycle of remodelling and renewal extending to an estimated 20 years in the proximal femur. Healthy femoral cortex incorporates multiple mechanisms that help prevent fracture. These have been described at multiple length scales from the individual bone mineral crystal to the scale of the femur itself and appear to operate hierarchically. Each cortical bone fracture begins as a sub-microscopic crack that enlarges under mechanical load, for example, that imposed by a fall. In these conditions, a crack will enlarge explosively unless the cortical bone is intrinsically tough (the opposite of brittle). Toughness leads to microscopic crack deflection and bridging and may be increased by adequate regulation of both mineral crystal size and the heterogeneity of mineral and matrix phases. The role of osteocytes in optimising toughness is beginning to be worked out; but many osteocytes die in situ without triggering bone renewal over a 20-year cycle, with potential for increasing brittleness. Furthermore, the superolateral cortex of the proximal femur thins progressively during life, so increasing the risk of buckling during a fall. Besides preserving or increasing hip BMD, pharmaceutical treatments have class-specific effects on the toughness of cortical bone, although dietary and exercise-based interventions show early promise.
Collapse
|
21
|
Aref MW, McNerny EMB, Brown D, Jepsen KJ, Allen MR. Zoledronate treatment has different effects in mouse strains with contrasting baseline bone mechanical phenotypes. Osteoporos Int 2016; 27:3637-3643. [PMID: 27439372 PMCID: PMC5543625 DOI: 10.1007/s00198-016-3701-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 07/06/2016] [Indexed: 12/16/2022]
Abstract
UNLABELLED Two strains of mice with distinct bone morphologies and mechanical properties were treated with zoledronate. Our results show a different response to drug treatment in the two strains providing evidence that baseline properties of structure/material may influence response to zoledronate. INTRODUCTION Bisphosphonates are highly effective in reducing fracture risk, yet some individuals treated with these agents still experience fracture. The goal of this study was to test the hypothesis that genotype influences the effect of zoledronate on bone mechanical properties. METHODS Skeletally mature male mice from genetic backgrounds known to have distinct baseline post-yield properties (C57/B6, high post-yield displacement; A/J, low post-yield displacement) were treated for 8 weeks with saline (VEH) or zoledronate (ZOL, 0.06 mg/kg subcutaneously once every 4 weeks) in a 2 × 2 study design. Ex vivo μCT and mechanical testing (4-pt bending) were conducted on the femur to assess morphological and mechanical differences. RESULTS Significant drug and/or genotype effects were found for several mechanical properties and significant drug × genotype interactions were found for measures of strength (ultimate force) and brittleness (total displacement, strain to failure). Treatment with ZOL affected bone biomechanical measures of brittleness (total displacement (-25 %) and strain to failure (-23 %)) in B6 mice significantly differently than in A/J mice. This was driven by unique drug × genotype effects on bone geometry in B6 animals yet likely also reflected changes to the tissue properties. CONCLUSION These data may support the concept that properties of the bone geometry and/or tissue at the time of treatment initiation play a role in determining the bone's mechanical response to zoledronate treatment.
Collapse
Affiliation(s)
- M W Aref
- Department of Anatomy and Cell Biology, MS 5035, Indiana University School of Medicine, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - E M B McNerny
- Department of Anatomy and Cell Biology, MS 5035, Indiana University School of Medicine, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - D Brown
- Department of Anatomy and Cell Biology, MS 5035, Indiana University School of Medicine, 635 Barnhill Dr., Indianapolis, IN, 46202, USA
| | - K J Jepsen
- Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, MI, USA
| | - M R Allen
- Department of Anatomy and Cell Biology, MS 5035, Indiana University School of Medicine, 635 Barnhill Dr., Indianapolis, IN, 46202, USA.
- Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA.
| |
Collapse
|
22
|
|
23
|
Burr DB. The use of finite element analysis to estimate the changing strength of bone following treatment for osteoporosis. Osteoporos Int 2016; 27:2651-2654. [PMID: 27447170 DOI: 10.1007/s00198-016-3707-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 07/08/2016] [Indexed: 02/03/2023]
Affiliation(s)
- D B Burr
- Department of Anatomy and Cell Biology, MS 5035, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Department of Biomedical Engineering, Indiana University-Purdue University, Indianapolis, IN, 46202, USA.
| |
Collapse
|
24
|
Higgins M, Morgan-John S, Badhe S. Simultaneous, bilateral, complete atypical femoral fractures after long-term alendronate use. J Orthop 2016; 13:401-3. [PMID: 27570414 DOI: 10.1016/j.jor.2016.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 07/03/2016] [Indexed: 01/20/2023] Open
Abstract
Over the past decade there have been increasing reports of atypical femoral fractures (AFFs) associated with bisphosphonate use. Reported cases of bilateral involvement usually refer to sequential injuries, or a complete fracture with an incomplete injury to the contralateral limb. In this case report we describe simultaneous, bilateral, complete atypical femoral fractures following a simple fall. A history of prodromal pain, previous radiological evidence of cortical thickening and long term alendronate therapy for osteoporosis secondary to corticosteroid treatment paint a classical picture of the presentation of an atypical fracture pattern of which orthopaedic surgeons should be aware.
Collapse
|
25
|
Bajaj D, Geissler JR, Allen MR, Burr DB, Fritton JC. Response to Courtney et al. Bone 2016; 89:77-79. [PMID: 25813582 DOI: 10.1016/j.bone.2015.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 02/24/2015] [Accepted: 03/11/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Devendra Bajaj
- Department of Orthopaedics, New Jersey Medical School, Rutgers University, 205 S. Orange Avenue, Newark, NJ 07103, USA.
| | - Joseph R Geissler
- Department of Orthopaedics, New Jersey Medical School, Rutgers University, 205 S. Orange Avenue, Newark, NJ 07103, USA; Department of Biomedical Engineering, New Jersey Institute of Technology, 323 Martin Luther King, Jr. Boulevard, Newark, NJ 07102, USA.
| | - Matthew R Allen
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA.
| | - David B Burr
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA.
| | - J Christopher Fritton
- Department of Orthopaedics, New Jersey Medical School, Rutgers University, 205 S. Orange Avenue, Newark, NJ 07103, USA; Department of Biomedical Engineering, New Jersey Institute of Technology, 323 Martin Luther King, Jr. Boulevard, Newark, NJ 07102, USA.
| |
Collapse
|
26
|
Burr DB. Bone Biomechanics and Bone Quality: Effects of Pharmaceutical Agents Used to Treat Osteoporosis. Clin Rev Bone Miner Metab 2016. [DOI: 10.1007/s12018-016-9217-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
27
|
|
28
|
Abstract
Osteogenesis imperfecta is a phenotypically and molecularly heterogeneous group of inherited connective tissue disorders that share similar skeletal abnormalities causing bone fragility and deformity. Previously, the disorder was thought to be an autosomal dominant bone dysplasia caused by defects in type I collagen, but in the past 10 years discoveries of novel (mainly recessive) causative genes have lent support to a predominantly collagen-related pathophysiology and have contributed to an improved understanding of normal bone development. Defects in proteins with very different functions, ranging from structural to enzymatic and from intracellular transport to chaperones, have been described in patients with osteogenesis imperfecta. Knowledge of the specific molecular basis of each form of the disorder will advance clinical diagnosis and potentially stimulate targeted therapeutic approaches. In this Seminar, together with diagnosis, management, and treatment, we describe the defects causing osteogenesis imperfecta and their mechanism and interrelations, and classify them into five groups on the basis of the metabolic pathway compromised, specifically those related to collagen synthesis, structure, and processing; post-translational modification; folding and cross-linking; mineralisation; and osteoblast differentiation.
Collapse
Affiliation(s)
- Antonella Forlino
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Joan C Marini
- Bone and Extracellular Matrix Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
29
|
Fan R, Gong H, Zhang R, Gao J, Jia Z, Hu Y. Quantification of Age-Related Tissue-Level Failure Strains of Rat Femoral Cortical Bones Using an Approach Combining Macrocompressive Test and Microfinite Element Analysis. J Biomech Eng 2016; 138:041006. [DOI: 10.1115/1.4032798] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Indexed: 12/15/2022]
Abstract
Bone mechanical properties vary with age; meanwhile, a close relationship exists among bone mechanical properties at different levels. Therefore, conducting multilevel analyses for bone structures with different ages are necessary to elucidate the effects of aging on bone mechanical properties at different levels. In this study, an approach that combined microfinite element (micro-FE) analysis and macrocompressive test was established to simulate the failure of male rat femoral cortical bone. Micro-FE analyses were primarily performed for rat cortical bones with different ages to simulate their failure processes under compressive load. Tissue-level failure strains in tension and compression of these cortical bones were then back-calculated by fitting the experimental stress–strain curves. Thus, tissue-level failure strains of rat femoral cortical bones with different ages were quantified. The tissue-level failure strain exhibited a biphasic behavior with age: in the period of skeletal maturity (1–7 months of age), the failure strain gradually increased; when the rat exceeded 7 months of age, the failure strain sharply decreased. In the period of skeletal maturity, both the macro- and tissue-levels mechanical properties showed a large promotion. In the period of skeletal aging (9–15 months of age), the tissue-level mechanical properties sharply deteriorated; however, the macromechanical properties only slightly deteriorated. The age-related changes in tissue-level failure strain were revealed through the analysis of male rat femoral cortical bones with different ages, which provided a theoretical basis to understand the relationship between rat cortical bone mechanical properties at macro- and tissue-levels and decrease of bone strength with age.
Collapse
Affiliation(s)
- Ruoxun Fan
- State Key Laboratory of Automotive Simulation and Control, Jilin University, Changchun 130025, China
- Department of Engineering Mechanics, Jilin University, Nanling Campus, Changchun 130025, China e-mail:
| | - He Gong
- Professor State Key Laboratory of Automotive Simulation and Control, Jilin University, Changchun 130025, China
- Department of Engineering Mechanics, Jilin University, Nanling Campus, Changchun 130025, China e-mail:
| | - Rui Zhang
- Department of Engineering Mechanics, Jilin University, Nanling Campus, Changchun 130025, China
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 10000, China e-mail:
| | - Jiazi Gao
- Department of Engineering Mechanics, Jilin University, Nanling Campus, Changchun 130025, China e-mail:
| | - Zhengbin Jia
- Department of Engineering Mechanics, Jilin University, Nanling Campus, Changchun 130025, China e-mail:
| | - Yanjuan Hu
- School of Mechatronic Engineering, Changchun University of Technology, Changchun 130025, China e-mail:
| |
Collapse
|
30
|
|