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Experimental & Molecular Medicine Jan 2021Metabolic activities are closely correlated with bone remodeling and long-term anti-resorptive bisphosphonate treatment frequently causes atypical femoral fractures...
Metabolic activities are closely correlated with bone remodeling and long-term anti-resorptive bisphosphonate treatment frequently causes atypical femoral fractures through unclear mechanisms. To explore whether metabolic alterations affect bone remodeling in femurs and lumbar vertebrae and whether anti-osteoporotic bisphosphonates perturb their reconstruction, we studied three mouse strains with different fat and lean body masses (BALB/c, C57BL6, and C3H mice). These mice displayed variable physical activity, food and drink intake, energy expenditure, and respiratory quotients. Following intraperitoneal calcein injection, double calcein labeling of the femoral diaphysis, as well as serum levels of the bone-formation marker procollagen type-I N-terminal propeptide and the bone-resorption marker C-terminal telopeptide of type-I collagen, revealed increased bone turnover in mice in the following order: C3H > BALB/c ≥ C57BL6 mice. In addition, bone reconstitution in femurs was distinct from that in lumbar vertebrae in both healthy control and estrogen-deficient osteoporotic mice with metabolic perturbation, particularly in terms of femoral trabecular and cortical bone remodeling in CH3 mice. Interestingly, subcutaneous administration of bisphosphonate risedronate to C3H mice with normal femoral bone density led to enlarged femoral cortical bones with a low bone mineral density, resulting in bone fragility; however, this phenomenon was not observed in mice with ovariectomy-induced femoral cortical bone loss. Together, these results suggest that diverse metabolic activities support various forms of bone remodeling and that femur remodeling differs from lumbar vertebra remodeling. Moreover, our findings imply that the adverse effect of bisphosphonate agents on femoral cortical bone remodeling should be considered when prescribing them to osteoporotic patients.
Topics: Animals; Biomechanical Phenomena; Bone Density Conservation Agents; Bone Remodeling; Collagen Type I; Cortical Bone; Estrogens; Femur; Fluoresceins; Lumbar Vertebrae; Mice; Mice, Inbred BALB C; Mice, Inbred C3H; Mice, Inbred C57BL; Osteoporosis; Risedronic Acid
PubMed: 33436949
DOI: 10.1038/s12276-020-00548-w -
Archives of Orthopaedic and Trauma... May 2022Despite the fact that osteotomies around the knee represent well-established treatment options for the redistribution of loads and forces within and around the knee...
INTRODUCTION
Despite the fact that osteotomies around the knee represent well-established treatment options for the redistribution of loads and forces within and around the knee joint, unforeseen effects of these osteotomies on the remaining planes and adjacent joints are still to be defined. It was, therefore, the aim of this study to determine the influence of a distal femoral rotation osteotomy on the coronal limb alignment and on the ischiofemoral space of the hip joint.
MATERIALS AND METHODS
Long-leg standing radiographs and CT-based torsional measurements of 27 patients undergoing supracondylar rotational osteotomies of the femur between 2012 and 2019 were obtained and utilized for the purpose of this study. Postoperative radiographs were obtained after union at the osteotomy site. The hip-knee-ankle angle (HKA), the mechanical lateral distal femur angle (mLDFA), and the ischiofemoral space were measured. Comparison between means was performed using the Wilcoxon-Mann-Whitney test.
RESULTS
Twenty-seven patients underwent isolated supracondylar external rotation osteotomy to reduce the overall antetorsion of the femur. The osteotomy resulted in a 2.4° ± 1.4° mean increase in HKA and 2.4 mm ± 1.7 mm increase in the ischiofemoral space (p < 0.001).
CONCLUSION
Supracondylar external rotation osteotomy of the femur leads to valgisation of the coronal limb alignment and increases the ischiofemoral space. This is resultant to the reorientation of the femoral antecurvature and the femoral neck. When planning a rotational osteotomy of the lower limb, this should be appreciated and may also aid in the decision regarding osteotomy site.
Topics: Femur; Femur Neck; Humans; Knee Joint; Lower Extremity; Osteotomy; Tibia
PubMed: 33355718
DOI: 10.1007/s00402-020-03704-z -
Journal of Biomechanics Jun 2021Estrogen deficiency activates bone resorbing cells (osteoclasts) and to a lesser extent bone forming cells (osteoblasts), resulting in a gap between resorption and...
Estrogen deficiency activates bone resorbing cells (osteoclasts) and to a lesser extent bone forming cells (osteoblasts), resulting in a gap between resorption and formation that leads to a net loss of bone. These cell activities alter bone architecture and tissue composition. Thus, the objective of this study is to examine whether multiscale (10 to 10 m) characterization can provide more integrated information to understand the effects of estrogen deficiency on the fracture risk of bone. This is the first study to examine the effects of estrogen deficiency on multiscale characteristics of the same bone specimen. Sprague-Dawley female rats (6 months old) were obtained for a bilateral ovariectomy (OVX) or a sham operation (sham). Micro-computed tomography of rat femurs provided bone volumetric, mineral density, and morphological parameters. Dynamic mechanical analysis, static elastic and fracture mechanical testing, and nanoindentation were also performed using the same femur. As expected, the current findings indicate that OVX reduces bone quantity (mass and bone mineral density) and quality (morphology, and fracture displacement). Additionally, they demonstrated reductions in amount and heterogeneity of tissue mineral density (TMD) and viscoelastic properties. The current results validate that multiscale characterization for the same bone specimen can provide more comprehensive insights to understand how the bone components contributed to mechanical behavior at different scales.
Topics: Animals; Bone Density; Female; Femur; Humans; Ovariectomy; Rats; Rats, Sprague-Dawley; X-Ray Microtomography
PubMed: 33915473
DOI: 10.1016/j.jbiomech.2021.110462 -
Journal of Orthopaedic Research :... Aug 2022The posterior condylar offset (PCO) has been proposed as a determinant of a postoperative range of motion after total knee arthroplasty, although there is no consensus....
The posterior condylar offset (PCO) has been proposed as a determinant of a postoperative range of motion after total knee arthroplasty, although there is no consensus. This study aimed to demonstrate the error introduced by forcing the femoral rotation to overlap both condyles for the "true" lateral X-ray projection for the PCO measurement. We hypothesize that the angular discrepancy between the posterior femoral cortical reference plane and the posterior condylar axis plane due to rotation invalidates the acquisition of reliable measurements on X-rays. We have measured the PCO in 50 "true" lateral X-rays and compared it with the medial and lateral condyles PCO's assessed on a computed tomography-scan-based three-dimensional (3D) model of each knee. PCO based on the 3D imaging differed significantly between the medial (25.8 ± 3.67 mm) and lateral (16.59 ± 2.92 mm) condyle. Three-dimensional PCO values differ significantly from those determined in the radiographic studies. Also, the mean values of the medial and lateral condyle PCO measurements differed significantly (p < 0.001) with all PCO measurements on radiographs. We have identified a difference between the posterior cortical plane and the posterior condylar axis projections, both on the axial plane with a mean value of 11.23° ± 3.64°. Our data show an interplane discrepancy angle between the posterior femoral diaphyseal cortical and the posterior condylar axis plane (due to the femur's necessary rotation to overlap both condyles) may invalidate the 2D X-ray PCO assessment as a reliable measurement.
Topics: Arthroplasty, Replacement, Knee; Femur; Humans; Knee Joint; Knee Prosthesis; Range of Motion, Articular; Reproducibility of Results
PubMed: 34717014
DOI: 10.1002/jor.25205 -
Journal of Orthopaedic Surgery and... Jan 2021Leg length discrepancy is often associated with distal femur angular deformities such as valgus or flexion. This study aims to report a new technique for simultaneous...
BACKGROUND
Leg length discrepancy is often associated with distal femur angular deformities such as valgus or flexion. This study aims to report a new technique for simultaneous limb lengthening and acute distal femoral angular correction.
METHODS
A retrospective chart review of patients undergoing a single procedure was conducted. Patients included had a single operation where they underwent distal femur osteotomy stabilized with a plate followed by antegrade nailing with a magnetically controlled intramedullary lengthening nail (PRECICE, Ellipse Technologies, Inc., Irvine, CA, USA) using a trochanteric entry.
RESULTS
Seven femurs from 7 patients were included. The average age at operation was 13.6 years, and the leg length difference was 51 mm (range 30-105 mm). Associated deformities were valgus (4), knee flexion contracture (2), and both valgus and flexion contracture (1). Lengthening achieved was 43 mm (P = 0.0036), with a consolidation index of 27 days/cm and reliability of 0.87 (6/7). The 5 patients with angulation had an improvement of valgus from 12 to 4° (P = 0.006) and of the mechanical axis deviation from 34 to 3 mm (P = 0.0001). The range of motion also improved in the 3 patients with contractures. Preoperative gait disturbance, hip and knee pain, and functional scoliosis resolved after the limb deformities were corrected.
CONCLUSION
Combining a magnetic internal lengthening nail with a second distal osteotomy stabilized with a plate can successfully correct limb length and distal femur deformity acutely without altering the expected result of each procedure.
Topics: Adolescent; Bone Lengthening; Bone Nails; Bone Plates; Child; Female; Femur; Fracture Fixation, Intramedullary; Humans; Leg; Leg Length Inequality; Magnetics; Male; Osteotomy; Range of Motion, Articular; Retrospective Studies
PubMed: 33451359
DOI: 10.1186/s13018-020-02168-6 -
The Bone & Joint Journal Apr 2014Many different lengths of stem are available for use in primary total hip replacement, and the morphology of the proximal femur varies greatly. The more recently... (Review)
Review
Many different lengths of stem are available for use in primary total hip replacement, and the morphology of the proximal femur varies greatly. The more recently developed shortened stems provide a distribution of stress which closely mimics that of the native femur. Shortening the femoral component potentially comes at the cost of decreased initial stability. Clinical studies on the performance of shortened cemented and cementless stems are promising, although long-term follow-up studies are lacking. We provide an overview of the current literature on the anatomical features of the proximal femur and the biomechanical aspects and clinical outcomes associated with the length of the femoral component in primary hip replacement, and suggest a classification system for the length of femoral stems.
Topics: Arthroplasty, Replacement, Hip; Biomechanical Phenomena; Femur; Hip Prosthesis; Humans; Periprosthetic Fractures; Prosthesis Design; Radiography
PubMed: 24692608
DOI: 10.1302/0301-620X.96B4.33036 -
Bone Jul 2023Metabolic abnormalities, such as diabetes mellitus and obesity, can impact bone quantity and/or bone quality. In this work, we characterize bone material properties, in...
Metabolic abnormalities, such as diabetes mellitus and obesity, can impact bone quantity and/or bone quality. In this work, we characterize bone material properties, in terms of structure and composition, in a novel rat model with congenic leptin receptor (LepR) deficiency, severe obesity, and hyperglycemia (type 2 diabetes-like condition). Femurs and calvaria (parietal region) from 20-week-old male rats are examined to probe bones formed both by endochondral and intramembranous ossification. Compared to the healthy controls, the LepR-deficient animals display significant alterations in femur microarchitecture and in calvarium morphology when analyzed by micro-computed X-ray tomography (micro-CT). In particular, shorter femurs with reduced bone volume, combined with thinner parietal bones and shorter sagittal suture, point towards a delay in the skeletal development of the LepR-deficient rodents. On the other hand, LepR-deficient animals and healthy controls display analogous bone matrix composition, which is assessed in terms of tissue mineral density by micro-CT, degree of mineralization by quantitative backscattered electron imaging, and various metrics extrapolated from Raman hyperspectral images. Some specific microstructural features, i.e., mineralized cartilage islands in the femurs and hyper-mineralized areas in the parietal bones, also show comparable distribution and characteristics in both groups. Overall, the altered bone microarchitecture in the LepR-deficient animals indicates compromised bone quality, despite the normal bone matrix composition. The delayed development is also consistent with observations in humans with congenic Lep/LepR deficiency, making this animal model a suitable candidate for translational research.
Topics: Humans; Rats; Male; Animals; Receptors, Leptin; Diabetes Mellitus, Type 2; Obesity; Femur; Skull; Leptin; Bone Density
PubMed: 37028238
DOI: 10.1016/j.bone.2023.116747 -
PloS One 2019The present study aimed to better characterize the morphogenesis of the femur from the embryonic to the early fetal periods. Sixty-two human fetal specimens (crown-rump...
The present study aimed to better characterize the morphogenesis of the femur from the embryonic to the early fetal periods. Sixty-two human fetal specimens (crown-rump length [CRL] range: 11.4-185 mm) from the Kyoto Collection were used for this study. The morphogenesis and internal differentiation process of the femur were analyzed in 3D using phase-contrast X-ray computed tomography and magnetic resonance imaging. The cartilaginous femur was first observed at Carnegie stage 18. Major anatomical landmarks were formed prior to the initiation of ossification at the center of the diaphysis (CRL, 40 mm), as described by Bardeen. The region with very high signal intensity (phase 5 according to Streeter's classification; i.e., area described as cartilage disintegration) emerged at the center of the diaphysis, which split the region with slightly low signal intensity (phase 4; i.e., cartilage cells of maximum size) in fetuses with a CRL of 40.0 mm. The phase 4 and phase 5 regions became confined to the metaphysis, which might become the epiphyseal cartilage plate. Femur length and ossified shaft length (OSL) showed a strong positive correlation with CRL. The OSL-to-femur length ratio rapidly increased in fetuses with CRL between 40 and 75 mm, which became moderately increased in fetuses with a CRL of ≥75 mm. Cartilage canal invasion occurred earlier at the proximal epiphysis (CRL, 62 mm) than at the distal epiphysis (CRL, 75 mm). Morphometry and Procrustes analysis indicated that changes in the femur shape after ossification were limited, which were mainly detected at the time of initial ossification and shortly after that. In contrast, femoral neck anteversion and torsion of the femoral head continuously changed during the fetal period. Our data could aid in understanding the morphogenesis of the femur and in differentiating normal and abnormal development during the early fetal period.
Topics: Cartilage; Crown-Rump Length; Epiphyses; Femur; Fetus; Growth and Development; Humans; Imaging, Three-Dimensional; Magnetic Resonance Imaging; Morphogenesis; Osteogenesis
PubMed: 31442281
DOI: 10.1371/journal.pone.0221569 -
The Journal of Bone and Joint Surgery.... Nov 2012Revision total hip arthroplasty (THA) is projected to increase by 137% from the years 2005 to 2030. Reconstruction of the femur with massive bone loss can be a... (Review)
Review
Revision total hip arthroplasty (THA) is projected to increase by 137% from the years 2005 to 2030. Reconstruction of the femur with massive bone loss can be a formidable undertaking. The goals of revision surgery are to create a stable construct, preserve bone and soft tissues, augment deficient host bone, improve function, provide a foundation for future surgery, and create a biomechanically restored hip. Options for treatment of the compromised femur include: resection arthroplasty, allograft prosthetic composite (APC), proximal femoral replacement, cementless fixation with a modular tapered fluted stem, and impaction grafting. The purpose of this article is to review the treatment options along with their associated outcomes in the more severe femoral defects (Paprosky types IIIb and IV) in revision THA.
Topics: Arthroplasty, Replacement, Hip; Bone Transplantation; Femur; Hip Prosthesis; Humans; Postoperative Complications; Reoperation; Transplantation, Homologous; Treatment Outcome
PubMed: 23118384
DOI: 10.1302/0301-620X.94B11.30791 -
Orthopaedic Surgery Sep 2022This study aims to investigate the reliability and clinical outcome of a newly developed classification system for patients with fibrous dysplasia (FD) of the femur and...
OBJECTIVE
This study aims to investigate the reliability and clinical outcome of a newly developed classification system for patients with fibrous dysplasia (FD) of the femur and adjacent bones, optimizing its evaluation and management.
METHODS
A total of 205 patients (121 female and 84 male) with FD in the femur and adjacent bones were included in this retrospective study. All affected femurs were measured and treated based on this classification at our institution between 2009 and 2019. Based on previous studies and extensive clinical follow-up, we cautiously proposed the West China Hospital radiographic classification for FD in femur and adjacent bones following corresponding treatment options. There are five types with five radiographic features, including proximal femur bone loss, coxa vara, femoral shaft deformity, genu valgum, and hip arthritis. The intraobserver and interobserver reproducibility of this classification was assessed by four observers using the Cohen kappa statistic. The clinical outcome was evaluated using the criteria of Guille.
RESULTS
At a median follow-up of 60 months (range 6-120), 205 patients (median 34.8 years old, range 18-73 years old) were categorized into the following five types: Type I 31.7%, Type II 30.2%, Type III 20.5%, Type IV 10.2%, and Type V 7.3%. The mean interobserver and intraobserver kappa scores were 0.85 (range 0.77-0.89) and 0.85 (range 0.79-0.92), respectively. For clinical outcomes, there was no significant difference in the postoperative Guille score for Type I patients (mean 9.01 ± 1.22). There was a significant increase in the postoperative Guille score in Type II, III, IV, and V, compared to the preoperative values (P < 0.01). For complications, two Type III patients reported pain, and one Type III patient had mild-to-moderate Trendelenburg gait. One Type IV patient had a mild Trendelenburg gait. And two Type V patients still had mild limping.
CONCLUSION
This classification is reproducible and serves as a tool for evaluating and treating FD in the femur and adjacent bones. Therefore, we recommend this classification for the diagnosis and treatment of FD-related deformities in the femur and adjacent bones.
Topics: Adolescent; Adult; Aged; Female; Femur; Hospitals; Humans; Lower Extremity; Male; Middle Aged; Reproducibility of Results; Retrospective Studies; Young Adult
PubMed: 35924702
DOI: 10.1111/os.13404