- Development of an in vivo bone fatigue damage model using axial compression of the rabbit forelimb. [Journal Article]
- JBJ Biomech 2016 Aug 25
- Many nontraumatic fractures seen clinically in patients with metabolic bone disorders or on antiresorptive treatment show an increased incidence of microdamage accumulation and impaired intracortical...
Many nontraumatic fractures seen clinically in patients with metabolic bone disorders or on antiresorptive treatment show an increased incidence of microdamage accumulation and impaired intracortical remodeling. However, the lack of basal remodeling and Haversian bone in rodents limits their translatability in studying bone damage repair mechanisms. The work presented here demonstrates the development of the forelimb loading model in rabbits, the smallest mammal with intracortical Haversian remodeling. The forelimbs of post-mortem female New Zealand white rabbits were loaded in axial end compression to determine their basic monotonic and fatigue properties. Following time zero characterization, stress fractures were created in vivo and animals were allowed to recover for a period of two to five weeks. The rabbit forelimb when loaded in axial compression demonstrates a consistent mid-diaphyseal fracture location characterized by a local mixed compression-bending loading environment. Forelimb apparent stiffness, when fatigue loaded, demonstrates a progressive increase until macrocrack formation, at which time apparent stiffness rapidly declines until failure. Stress fractures in the rabbit ulna display robust periosteal expansion and woven bone formation two weeks following fracture. Subsequent healing at five weeks post-fracture is marked by woven bone densification, resorption and intracortical remodeling along the stress fracture line. The rabbit forelimb fatigue model is a promising new platform by which bone׳s response to damage may be studied.
- [An experimental study of bioglass implants in bone]. [Journal Article]
- IOInt Orthop 1982; 6(1):1-7
- The tolerance and response of bone to bioglass have been studied using implants of various chemical constitution in animals.Glass discs were inserted between the inner and outer tables of the skull i...
The tolerance and response of bone to bioglass have been studied using implants of various chemical constitution in animals.Glass discs were inserted between the inner and outer tables of the skull in 32 rabbits and small glass stick were implanted in the medullary cavity of long bones in 6 dogs. The results were analysed between 6 and 18 months later. High resolution radiographs and histopathological examination were performed.Some glass behaves like an inert material but other specimens are biodegradable and induce a satisfactory bone response in adjacent bone. Any new bone formation does not follow the classical stages of connective tissue, cartilage and woven bone. Bioglass is more suitable for bone than many other materials now in use and further applications in orthopaedic surgery may be considered.
- Clinicopathological Features of a Series of 27 Cases of Post-Denosumab Treated Giant Cell Tumors of Bones: A Single Institutional Experience at a Tertiary Cancer Referral Centre, India. [Journal Article]
- POPathol Oncol Res 2016 Oct 8
- Giant cell tumor of bone (GCTB) is mostly a benign tumor, but associated with recurrences and metastasis. Lately, denosumab is being utilized in the treatment of certain GCTBs. Twenty-seven tumors, a...
Giant cell tumor of bone (GCTB) is mostly a benign tumor, but associated with recurrences and metastasis. Lately, denosumab is being utilized in the treatment of certain GCTBs. Twenty-seven tumors, analyzed in the present study, occurred in 16 males and 11 females (M: F = 1.45:1), in the age-range of 16 to 47 years (mean = 29.5, median = 29). Most tumors were identified in the tibia(6) and femur(6), followed by the humerus(3), radius(3), pelvis(3), fibula(3), sacrum(1), metacarpal(1) and metatarsal(1) bones. There were 18(66.6 %) primary and 9(33.3 %) recurrent tumors. Exact tumor size (19 cases) varied from 3.7 to 15 cm (mean = 7.8, median = 6.4). Eight of the 19 tumors (42.1 %) had size more than or equal to 8 cm. On histopathologic examination of post-denosumab treated specimens, more than half cases (15)(55.5 %) revealed complete absence of osteoclast-like giant cells (OCLGs) and 12 cases revealed residual OCLGCs. In addition, there was replacement by fibro-osseous tissue, including reactive woven bone or osteoid in most cases, followed by variable amount of spindle cells, hyalinisation, fibrosis and chronic inflammatory cells, including lymphocytes, macrophages and plasma cells. Post-treatment follow-up (25 cases, 92.5 %), over 7-27 months duration (median = 18), revealed 20 cases continuously disease-free. Five patients developed recurrences at 9, 12, 13, 14 and 18 months, respectively. Out of these, who underwent repeat surgical intervention, 4 patients are alive with no evidence of disease and a single patient, planned for a second surgery, is alive-with-disease. Denosumab was mostly offered to patients with large sized, borderline salvageable tumors, in order to decrease the morbidity of index surgical procedure, that led to disappearance of OCLGCs in most cases. Post-denosumab treated GCT cases appear as low grade osteosarcomas on histopathologic examination, but lack the clinical behaviour of an osteosarcoma, therefore may be considered as pseudo malignant bony lesions.
- Comparison of early osseointegration of SLA(®) and SLActive(®) implants in maxillary sinus augmentation: a pilot study. [Journal Article]
- COClin Oral Implants Res 2016 Sep 29
- CONCLUSIONS: Both time and the use of hydrophilic implant surface had a positive impact on %BIC around implants placed into augmented maxillary sinuses. Hydrophilic implant surfaces also had a positive impact on surrounding tissue composition. Larger trials are needed to better assess and detect differences between these two surfaces in augmented maxillary sinuses.
- Intra-articular osteoid osteoma of the calcaneus: a case report and review. [Journal Article]
- RCRadiol Case Rep 2016; 11(3):212-6
- Osteoid osteoma of the calcaneus is rare and frequently misdiagnosed as arthritis because of similar symptoms. In addition, radiographic findings may be nonspecific, and magnetic resonance imaging (M...
Osteoid osteoma of the calcaneus is rare and frequently misdiagnosed as arthritis because of similar symptoms. In addition, radiographic findings may be nonspecific, and magnetic resonance imaging (MRI) may show a bone marrow edema and changes in adjacent soft tissue. A 19-year-old man presented with a 6-month history of persistent pain and swelling in the left hind foot; diagnostic computed tomography and MRI analyses revealed lesions suggesting an intra-articular osteoid osteoma of the calcaneus. Initial MRI did not show specific findings. On operation, the tumor was removed by curettage; pathologic findings demonstrated woven bone trabeculae surrounded by connective tissue, confirming the diagnosis. To the best of our knowledge, MRI scans in all cases of calcaneal osteoid osteoma reported till 3 months after the injury exhibited a nidus. We believe that calcaneal osteoid osteoma should be considered as a differential diagnosis in patients undergoing MRI 3 months after symptom presentation; early computed tomography is critical in diagnosis.
- Four-week histologic evaluation of grafted calvarial defects with adjunctive hyperbaric oxygen therapy in rats. [Journal Article]
- JPJ Periodontal Implant Sci 2016; 46(4):244-53
- CONCLUSIONS: Within the limitations of this study, the present findings indicate that adjunctive HBO and EGCG/BMP-2 could be beneficial for new bone formation in rat calvarial defects.
- In vivo erosion of orthopedic screws prepared from nacre (mother of pearl). [Journal Article]
- OTOrthop Traumatol Surg Res 2016 Aug 20
- CONCLUSIONS: Screws prepared from nacre have the advantage of an in vivo resorbability by macrophage-derived cells and an osteoconductive apposition in contact with the material without triggering a local inflammatory reaction.
- Effect of combined treatment with zoledronic acid and parathyroid hormone on mouse bone callus structure and composition. [Journal Article]
- BONEBone 2016; 92:70-78
- In recent years, great interest in combined treatment of parathyroid hormone (PTH) with anti-resorptive therapy has emerged. PTH has been suggested to aid bridging of atrophic fractures and improve s...
In recent years, great interest in combined treatment of parathyroid hormone (PTH) with anti-resorptive therapy has emerged. PTH has been suggested to aid bridging of atrophic fractures and improve strength in closed fracture models. Bisphosphonate treatments typically result in a larger woven bone callus that is slower to remodel. The combination of both drugs has been demonstrated to be effective for the treatment of osteoporotic bone loss in many preclinical studies. However, the effect of combined treatment on fracture repair is still largely unexplored. In this study, we aimed to compare these drugs as single-agent and in combination in a murine closed fracture model. We wanted to assess potential differences in material properties, morphometry and in the development of the lacuno-canalicular network. A total of 40 female, 11-week-old wild type mice underwent a closed fracture on the midshaft of the tibia and were assigned to four groups (n=8-10 per group). Beginning on post-operative day 8, animals received different subcutaneous injections. Group 1 received a single injection of saline solution and Group 2 of zoledronic acid (ZA). Group 3 received daily dosing of PTH. Group 4 received a dual treatment, starting with a single dose of ZA followed by daily injection of PTH. Three weeks after fracture, all animals were euthanized and tibiae were assessed using micro-computed tomography (micro-CT), high-resolution micro-CT (HR micro-CT), Raman spectroscopy, quantitative histomorphometry, and deconvolution microscopy (DV microscopy). Combined treatment showed a significant increase of 41% in bone volume fraction and a significant decrease of 61% in the standard deviation of the trabecular spacing compared to vehicle, both known to be strong predictors of callus strength. An analysis via HR micro-CT showed similar results on all groups for lacunar numerical density, whereas mean lacuna volume was found to be higher compared to vehicle in treated groups, but only PTH mono-treatment showed a significant increase compared to vehicle (+45%). Raman spectroscopy did not reveal detectable changes in material properties of the bone calluses. Sclerostin staining, tartrate resistant acid phosphatase (TRAP) staining and canalicular analysis with DV microscopy on a subset of samples did not display distinctive difference in any of the treatments. We therefore consider PTH+ZA treatment beneficial for bone healing. No clear negative effect on bone quality was detected during this study.
- Histomorphological and Histomorphometric Analyses of Grade IV Commercially Pure Titanium and Grade V Ti-6Al-4V Titanium Alloy Implant Substrates: An In Vivo Study in Dogs. [Journal Article]
- IDImplant Dent 2016; 25(5):650-5
- CONCLUSIONS: Both titanium substrates were biocompatible and osseoconductive at the bone tissue level.
New Search Next
- Osthole Promotes Endochondral Ossification and Accelerates Fracture Healing in Mice. [Journal Article]
- CTCalcif Tissue Int 2016 Aug 18
- Osthole has been found to restore bone mass in preclinical osteoporotic models. In the present study, we investigated the effects of osthole on bone fracture repair in mice. Adult C57BL/6 mice were s...
Osthole has been found to restore bone mass in preclinical osteoporotic models. In the present study, we investigated the effects of osthole on bone fracture repair in mice. Adult C57BL/6 mice were subjected to transverse femoral fractures and administrated orally with 20 mg/kg osthole and vehicle solvent daily from week 1 post-operation. Fracture callus were analyzed by plain radiography, micro-computed tomography, histology, molecular imaging and immunohistochemistry and tartrate-resistant acid phosphatase staining. Results demonstrated that osthole treatment enhanced removal of cartilage and bony union during reparative stage without significant interfering on remodeling process. In vivo molecular imaging showed bone formation rate of the treatment group was almost twofold of control group at week 2 post-operation. Osthole augmented the expression of alkaline phosphatase and collagen type X in hypertrophic chondrocytes as well as expression of bone morphogenetic protein-2, osteocalcin and alkaline phosphatase in osteoblastic cells, indicating it promoted mineralization of hypertrophic cartilage and woven bone growth simultaneously during endochondral healing. In summary, osthole promotes endochondral ossification via upregulation of maturation osteogenic marker genes in chondrocytes and subsequently accelerates fracture repair and bony fusion.