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Biomedicine & Pharmacotherapy =... Aug 2023Memantine is an N-methyl-D-aspartate (NMDA) receptor antagonist used in the treatment of Alzheimer's disease (AD). NMDA receptors are expressed on bone cells. The aim of...
Memantine is an N-methyl-D-aspartate (NMDA) receptor antagonist used in the treatment of Alzheimer's disease (AD). NMDA receptors are expressed on bone cells. The aim of the present study was to investigate the effects of memantine on the rat musculoskeletal system. Taking into account that most of female AD patients are postmenopausal, the study was carried out on intact and ovariectomized (estrogen-deficient) rats. Mature Wistar rats were divided into following groups: non-ovariectomized (NOVX) control rats, NOVX rats treated with memantine, ovariectomized (OVX) control rats, and OVX rats treated with memantine. Memantine (2 mg/kg p.o.) was administered once daily for four weeks, starting one week after ovariectomy. The serum bone turnover marker and cytokine levels, bone density, mass, mineralization, mechanical properties, histomorphometric parameters of compact and cancellous bone, skeletal muscle mass and grip strength were determined. In NOVX rats, memantine slightly decreased the strength of compact bone of the femoral diaphysis (parameters in the yield point) and unfavorably affected histomorphometric parameters of cancellous bone (the femoral epiphysis and metaphysis). In OVX rats, in which estrogen deficiency induced osteoporotic changes, memantine increased the phosphorus content in the femoral bone mineral. No other effects on bone were observed in the memantine-treated OVX rats. In conclusion, the results of the present study indicated slight damaging skeletal effects of memantine in rats with normal estrogen levels.
Topics: Rats; Female; Animals; Humans; Rats, Wistar; Memantine; Bone and Bones; Estrogens; Bone Density; Ovariectomy
PubMed: 37229803
DOI: 10.1016/j.biopha.2023.114921 -
Clinical Orthopaedics and Related... May 2021
Topics: Epiphyses; Epiphyses, Slipped; Humans; Rotation; Slipped Capital Femoral Epiphyses
PubMed: 33560677
DOI: 10.1097/CORR.0000000000001656 -
Bone Reports Jun 2018Fractures are common traumatic injuries that mainly occur in the metaphyses of long bones such as the proximal humerus, distal radius, and proximal femur. However, most...
Fractures are common traumatic injuries that mainly occur in the metaphyses of long bones such as the proximal humerus, distal radius, and proximal femur. However, most studies of fracture repair processes have focused on the diaphyseal region. In this study, we compared the bone repair processes of the metaphysis and the diaphysis of the mouse tibia. Bone apertures were formed in the tibial metaphysis and diaphysis. At indicated times after surgery, samples were collected, and the healing process was investigated using micro-computed tomography, as well as histological, immunohistochemical, and mRNA expression analyses. In the metaphysis, cartilage formation was not detected on the periosteal side. The bone aperture was filled with newly formed bone produced from bone marrow at day 7. In the case of the diaphysis, cartilage was formed around the aperture at day 4 and sequentially replaced by bone on the periosteal side. The bone aperture was filled with newly formed bone at day 14. In the bone marrow, expression of the osteogenic markers such as alkaline phosphatase, osteocalcin, and type I collagen, appeared earlier with metaphyseal injury than with diaphyseal injury. The mRNA expression of chondrogenesis markers was markedly upregulated in the diaphysis compared with that in the metaphysis on the periosteal side. These results indicate differences in the bone repair processes of the two regions, suggesting functional heterogeneity of the periosteum and bone marrow mesenchymal cells in response to bone fractures.
PubMed: 29276733
DOI: 10.1016/j.bonr.2017.11.003 -
International Journal of Molecular... Sep 2022The discovery of bone morphogenetic proteins (BMPs) inspired hope for the successful treatment of bone disorders, but side effects worsening the clinical effects were... (Review)
Review
The discovery of bone morphogenetic proteins (BMPs) inspired hope for the successful treatment of bone disorders, but side effects worsening the clinical effects were eventually observed. BMPs exert a synergistic effect, stimulating osteogenesis; however, predicting the best composition of growth factors for use in humans is difficult. Chondrocytes present within the growth plate produce growth factors stored in calcified cartilage adhering to metaphysis. These factors stimulate initial bone formation in metaphysis. We have previously determined the growth factors present in bovine calcified cartilage and produced by rat epiphyseal chondrocytes. The results suggest that growth factors stimulating physiological ossification are species dependent. The collection of human calcified cartilage for growth factors determination does not appear feasible, but chondrocytes for mRNA determination could be obtained. Their collection from young recipients, in view of the Academy of Medical Royal Colleges Recommendation, would be ethical. The authors of this review do not have facilities to conduct such a study and can only appeal to competent institutions to undertake the task. The results could help to formulate a better recipe for the stimulation of bone formation and improve clinical results.
Topics: Animals; Bone Morphogenetic Proteins; Cartilage; Cattle; Chondrocytes; Growth Plate; Humans; Osteogenesis; RNA, Messenger; Rats
PubMed: 36142232
DOI: 10.3390/ijms231810327 -
Clujul Medical (1957) 2014Elastic stable intramedullary nailing (ESIN) is a minimally invasive technique. According to this technique, two elastic nails are introduced through the metaphysis into... (Review)
Review
Elastic stable intramedullary nailing (ESIN) is a minimally invasive technique. According to this technique, two elastic nails are introduced through the metaphysis into the medullary canal, advanced through the fracture site and impacted into the opposite metaphysis. These nails are preformed in a C-shaped manner, which allows for their precise orientation and the creation of an elastic system that resists deformation.
PubMed: 26528004
DOI: 10.15386/cjmed-274 -
Foot & Ankle Orthopaedics Jan 2021Autogenous cancellous bone graft and bone marrow aspirate are commonly used in lower extremity fusion procedures to enhance fusion potential, and frequently in revision...
BACKGROUND
Autogenous cancellous bone graft and bone marrow aspirate are commonly used in lower extremity fusion procedures to enhance fusion potential, and frequently in revision situations where bone loss and osteolysis may be a feature. The tibial metaphysis is a common donor site for bone graft, with the procedure typically performed using a curette or trephine to harvest the cancellous bone. Some limitations of this technique include suboptimal harvest of the marrow portion in particular, incomplete graft harvest, and loss of graft material during the harvest process. We describe a novel vacuum-assisted bone harvesting device to acquire cancellous bone and marrow from the proximal tibia.
METHODS
This is a retrospective study of a single surgeon's consecutive patients who underwent foot and ankle arthrodesis procedures using proximal tibia autograft obtained using a vacuum-assisted bone harvesting device. Descriptive statistics were used to summarize patient and operative characteristics and outcomes. We identified 9 patients with a mean age of 51 years, 4 of whom were female.
RESULTS
On average, the skin incision was slightly more than 2 cm, and 27 mL of solid graft and 16 mL of liquid phase aspirate were collected. At 6 weeks after the procedure, there was minimal to no pain at the donor site, and we did not observe any fractures or other complications.
CONCLUSIONS
We report the use of a novel vacuum-assisted curette device to harvest bone graft from the proximal tibial metaphysis for use in foot and ankle fusions. This device has been reliable and efficient in clinical practice.
LEVEL OF EVIDENCE
Level IV, retrospective case series.
PubMed: 35097423
DOI: 10.1177/2473011420981901 -
The Journal of Endocrinology Feb 2018Impaired resorption of cartilage matrix deposited during endochondral ossification is a defining feature of juvenile osteopetrosis. Growing, leptin-deficient mice...
Impaired resorption of cartilage matrix deposited during endochondral ossification is a defining feature of juvenile osteopetrosis. Growing, leptin-deficient mice exhibit a mild form of osteopetrosis. However, the extent to which the disease is (1) self-limiting and (2) reversible by leptin treatment is unknown. We addressed the first question by performing histomorphometric analysis of femurs in rapidly growing (2-month-old), slowly growing (4-month-old) and skeletally mature (6-month-old) wild-type (WT) and male mice. Absent by 6 months of age in WT mice, cartilage matrix persisted to varying extents in distal femur epiphysis, metaphysis and diaphysis in mice, suggesting that the osteopetrotic phenotype is not entirely self-limiting. To address the second question, we employed hypothalamic recombinant adeno-associated virus (rAAV) gene therapy to restore leptin signaling in mice. Two-month-old mice were randomized to one of the three groups: (1) untreated control, (2) rAAV-Leptin or (3) control vector rAAV-green fluorescent protein and vectors injected intracerebroventricularly. Seven months later, rAAV-leptin-treated mice exhibited no cartilage in the metaphysis and greatly reduced cartilage in the epiphysis and diaphysis. At the cellular level, the reduction in cartilage was associated with increased bone turnover. These findings (1) support the concept that leptin is important for normal replacement of cartilage by bone, and (2) demonstrate that osteopetrosis in mice is bone-compartment-specific and reversible by leptin at skeletal sites capable of undergoing robust bone turnover.
Topics: Animals; Bone Density; Genetic Therapy; Hypothalamus; Leptin; Male; Mice; Mice, Inbred C57BL; Mice, Obese; Mice, Transgenic; Obesity; Osteoclasts; Osteopetrosis
PubMed: 29191939
DOI: 10.1530/JOE-17-0524 -
The Yale Journal of Biology and Medicine 1993Skeletal tissues from children sustaining acute skeletal trauma were analyzed with detailed radiologic and histologic techniques to assess the failure patterns of the... (Review)
Review
Skeletal tissues from children sustaining acute skeletal trauma were analyzed with detailed radiologic and histologic techniques to assess the failure patterns of the developing skeleton. In the physis- and epiphysis-specific fracture propagation varied, usually going through the portion of the hypertrophic zone adjacent to the metaphysis. However, the physeal fracture in types 1 and 2 sometimes involved the germinal zone. There may also be microscopic propagation at oblique angles from the primary fracture plane, splitting cell columns apart longitudinally. The cartilage canals supplying the germinal zone appear to be "weak" areas into which the fracture may propagate, especially in infancy. Incomplete type 1 physeal fractures, which cannot be detected by routine radiography, may occur. Types 1, 2, and 4 physeal injuries may be comminuted. In type 3 injuries, discrete segments of physis that include the germinal zone may "adhere" to the metaphysis, separating the cells from their normal vascularity. In types 2 and 3, comminution may occur at the site of fracture redirection from the physis. Direct type 5 crushing of the physeal germinal zone does not occur, even in the presence of significant pressure-related changes within other areas of the epiphysis. Type 7 separation between cartilage and bone at any chondro-osseous epiphyseal interface may occur, but is similarly impossible to diagnose radiographically. In the metaphysis torus, fractures result from plastic deformation of the cortex, coupled with a partial microfracturing that may be difficult to visualize with clinical radiography. Some of the energy absorption may also be transmitted to the physis, causing metaphyseal hemorrhage adjacent to the growth plate and variable microscopic damage within the physis. In the diaphysis, the greenstick fracture is associated with longitudinal tensile failure through the developing osteons of the "intact" cortex. The inability of these failure patterns to "narrow" after the fracture force dissipates is the probable cause of retained bowing (plastic deformation). In both torus and greenstick fractures, the fractured bone ends show micro-splitting through the osteoid seams. In the diaphysis, metaphysis, and epiphyseal ossification center there may be areas of focal hemorrhage and microfracture that correlate with the reported MRI phenomenon of "bone bruising." Again, such injury cannot be diagnosed during routine radiography.
Topics: Animals; Bone Development; Bone and Bones; Cartilage; Child; Child, Preschool; Contusions; Disease Susceptibility; Epiphyses; Fractures, Bone; Fractures, Cartilage; Humans; Infant; Rabbits; Radiography; Rats
PubMed: 8209558
DOI: No ID Found -
Journal of Orthopaedic Surgery (Hong... 2020Constitutional varus in the coronal plane is formed based on the Hueter-Volkmann's law. The varus deformity occurs at the proximal metaphysis of the tibia and the tibial...
PURPOSE
Constitutional varus in the coronal plane is formed based on the Hueter-Volkmann's law. The varus deformity occurs at the proximal metaphysis of the tibia and the tibial condyle rotates medially. In the sagittal plane, we hypothesized that the posterior slope angle of the tibial articular surface may also occur at the proximal metaphysis and the tibial condyle rotates posteriorly. The purpose of this study was to verify the hypothesis.
METHODS
A total of 208 patients who underwent TKA had lateral view proximal tibia digital radiograph on which seven parameters were analyzed. The posterior slope angle of the tibial articular surface relative to the anterior wall of the tibial condyle and that relative to the anterior cortex of the tibial shaft were assessed. Correlation between the position of the tibial condyle and the posterior slope angle of the articular surface were assessed.
RESULTS
The proximal tibial condyle itself did not have a posterior slope in the 86.5% of the participants. Posterior rotation of the tibial condyle created posterior slope of the tibial articular surface relative to the anterior cortex of the tibial shaft. The more tibial condyle was posteriorly rotated, the more the tibial articular surface shifted posteriorly.
CONCLUSION
Study findings showed that the posterior tibial slope occurs at the proximal metaphysis of the tibia, and the tibial condyle rotates posteriorly. The posterior tibial slope involves the posterior shift of the tibial articular surface. The posterior tibial slope is mainly created by the posterior rotation of the tibial condyle.
Topics: Aged; Aged, 80 and over; Female; Humans; Knee Joint; Male; Middle Aged; Orthopedic Procedures; Range of Motion, Articular; Tibia
PubMed: 33272082
DOI: 10.1177/2309499020975580 -
Acta Orthopaedica Aug 2009It has already been shown in animals and using anatomical human specimens that chronic slippage of the adolescent upper (capital) femoral epiphysis is unlikely to take...
BACKGROUND
It has already been shown in animals and using anatomical human specimens that chronic slippage of the adolescent upper (capital) femoral epiphysis is unlikely to take place by shearing due to the presence of an epiphyseal tubercle projecting down into the metaphysis.
MATERIAL, RESULTS, AND INTERPRETATION
Plain radiographs of 20 adolescents and CT scans of 9 of them were analyzed for evidence of the size and presence of this tubercle in vivo. These cases showed that CT scanography is the investigation of choice to illustrate this largely undescribed anatomical feature. They also illustrate the epiphyseal tubercle well, both in the anatomical position and at various stages of "epiphyseal slippage", and confirm that it has a significant restraining effect on any tendency of the epiphysis to alter its position relative to the metaphysis.
Topics: Adolescent; Child; Epiphyses; Epiphyses, Slipped; Female; Femur; Hip; Humans; Male; Rotation; Tomography, X-Ray Computed
PubMed: 19626468
DOI: 10.3109/17453670903153550