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Medicine Jun 2024To elucidate the differences in mechanical performance between a novel axially controlled compression spinal rod (ACCSR) for lumbar spondylolysis (LS) and the common...
BACKGROUND
To elucidate the differences in mechanical performance between a novel axially controlled compression spinal rod (ACCSR) for lumbar spondylolysis (LS) and the common spinal rod (CSR).
METHODS
A total of 36 ACCSRs and 36 CSRs from the same batch were used in this study, each with a diameter of 6.0 mm. Biomechanical tests were carried out on spinal rods for the ACCSR group and on pedicle screw-rod internal fixation systems for the CSR group. The spinal rod tests were conducted following the guidelines outlined in the American Society for Testing and Materials (ASTM) F 2193, while the pedicle screw-rod internal fixation system tests adhered to ASTM F 1798-97 standards.
RESULTS
The stiffness of ACCSR and CSR was 1559.15 ± 50.15 and 3788.86 ± 156.45 N/mm (P < .001). ACCSR's yield load was 1345.73 (1297.90-1359.97) N, whereas CSR's was 4046.83 (3805.8-4072.53) N (P = .002). ACCSR's load in the 2.5 millionth cycle of the fatigue four-point bending test was 320 N. The axial gripping capacity of ACCSR and CSR was 1632.53 ± 165.64 and 1273.62 ± 205.63 N (P = .004). ACCSR's torsional gripping capacity was 3.45 (3.23-3.47) Nm, while CSR's was 3.27 (3.07-3.59) Nm (P = .654). The stiffness of the pedicle screws of the ACCSR and CSR group was 783.83 (775.67-798.94) and 773.14 (758.70-783.62) N/mm (P = .085). The yield loads on the pedicle screws of the ACCSR and CSR group was 1345.73 (1297.90-1359.97) and 4046.83 (3805.8-4072.53) N (P = .099).
CONCLUSION
Although ACCSR exhibited lower yield load, stiffness, and fatigue resistance compared to CSR, it demonstrated significantly higher axial gripping capacity and met the stress requirement of the human isthmus. Consequently, ACCSR presents a promising alternative to CSR for LS remediation.
Topics: Lumbar Vertebrae; Humans; Biomechanical Phenomena; Spondylolysis; Pedicle Screws; Materials Testing; Internal Fixators; Mechanical Tests
PubMed: 38847663
DOI: 10.1097/MD.0000000000038520 -
Nature Communications Jun 2024Chondrocyte differentiation controls skeleton development and stature. Here we provide a comprehensive map of chondrocyte-specific enhancers and show that they provide a...
Chondrocyte differentiation controls skeleton development and stature. Here we provide a comprehensive map of chondrocyte-specific enhancers and show that they provide a mechanistic framework through which non-coding genetic variants can influence skeletal development and human stature. Working with fetal chondrocytes isolated from mice bearing a Col2a1 fluorescent regulatory sensor, we identify 780 genes and 2'704 putative enhancers specifically active in chondrocytes using a combination of RNA-seq, ATAC-seq and H3K27ac ChIP-seq. Most of these enhancers (74%) show pan-chondrogenic activity, with smaller populations being restricted to limb (18%) or trunk (8%) chondrocytes only. Notably, genetic variations overlapping these enhancers better explain height differences than those overlapping non-chondrogenic enhancers. Finally, targeted deletions of identified enhancers at the Fgfr3, Col2a1, Hhip and, Nkx3-2 loci confirm their role in regulating cognate genes. This enhancer map provides a framework for understanding how genes and non-coding variations influence bone development and diseases.
Topics: Animals; Enhancer Elements, Genetic; Humans; Chondrocytes; Mice; Chondrogenesis; Receptor, Fibroblast Growth Factor, Type 3; Collagen Type II; Gene Expression Regulation, Developmental; Bone Development; Extremities; Male; Cell Differentiation; Transcription Factors; Female
PubMed: 38844479
DOI: 10.1038/s41467-024-49203-2 -
Nigerian Journal of Clinical Practice May 2024The occipital spur (OS) can be described as an abnormal elongation of the external occipital protuberance (EOP). The cephalic index (CI) refers to the ratio of width to...
BACKGROUND
The occipital spur (OS) can be described as an abnormal elongation of the external occipital protuberance (EOP). The cephalic index (CI) refers to the ratio of width to length in any skull.
AIM
The aim of the present study was to evaluate the frequency and types of OS. It also aimed to determine the mean CI and the distribution of skull types using cone beam computed tomography (CBCT). And to determine if there was a relationship between the cephalic index and the presence and types of OS.
METHODS
CBCT scans from 523 patients were included in the study. OSs were classified as type 1 (flat), type 2 (crest), and type 3 (spine). Skull length and width were measured on axial sections and the CI was calculated. Based on the cephalic index (CI), skull types were classified as dolichocephalic (CI < 75), mesocephalic (75 < CI < 80), brachycephalic (80 < CI < 85), and hyperbrachycephalic (CI > 85).
RESULTS
The most common cranial types in the study group were brachycephalic (44.7%), mesocephalic (28.3%), hyperbrachycephalic (21.2%), and dolichocephalic (5.7%). Regarding the presence of OS, 54.3% of the participants had no OS, 23.1% had flat type, 15.3% had crest type, and 7.2% had spin type OS. There was a statistically significant difference (P < 0.05) in the frequency of OS according to skull type.
CONCLUSION
This study, the first to evaluate CI and OS using CBCT, concludes that brachycephaly is the most common cranial type. OS is more common in mesocephalic and dolichocephalic skulls, at older ages, and in males.
Topics: Humans; Cone-Beam Computed Tomography; Male; Female; Occipital Bone; Adult; Middle Aged; Cephalometry; Adolescent; Young Adult; Child; Aged; Child, Preschool; Skull
PubMed: 38842715
DOI: 10.4103/njcp.njcp_45_24 -
The South African Journal of... 2024Ankylosing spondylitis (AS) is characterised as a chronic inflammatory disease of the axial skeleton. The force platform is an option for performing the postural... (Review)
Review
BACKGROUND
Ankylosing spondylitis (AS) is characterised as a chronic inflammatory disease of the axial skeleton. The force platform is an option for performing the postural assessment of these individuals.
OBJECTIVES
To review and evaluate the behaviour of the centre of pressure (CoP) variables during the postural control examination in patients with AS compared to a control group.
METHOD
A systematic review, registered in PROSPERO, that followed the PRISMA Statement. A search was carried out in the following databases: Medline, Web of Science, Embase, Scopus, and Scielo, from 1945 to 2023. Studies were selected that aimed to understand the use of the force platform for the assessment of postural control. The risk of bias assessment was performed using the AXIS tool.
RESULTS
Five studies were included, with a total of 247 participants. The assessment of risk of bias presented high scores in the AXIS tool. Patients with a diagnosis of AS presented increased thoracic kyphosis in most of the studies, as well as large displacements in the anteroposterior (AP) and mediolateral (ML) directions, and altered total mean velocity (TMV) and frequency, indicating worse postural stability. Regarding the functional status, the most used questionnaires were the Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI) and Bath Ankylosing Disease Activity Index (BASDAI).
CONCLUSION
Patients with ankylosing spondylitis present postural instability, verified by means of higher values of centre of posture variables.
CLINICAL IMPLICATIONS
Individuals with ankylosing spondylitis presented postural instability and balance deficit. Therefore, exercises for balance training and postural control are essential in the clinical management of these patients.
PubMed: 38841593
DOI: 10.4102/sajp.v80i1.1953 -
Frontiers in Immunology 2024Currently, there is a lack of an objective quantitative measure to comprehensively evaluate the inflammatory activity of axSpA, which poses certain challenges in...
BACKGROUND
Currently, there is a lack of an objective quantitative measure to comprehensively evaluate the inflammatory activity of axSpA, which poses certain challenges in accurately assessing the disease activity.
OBJECTIVE
To explore the value of combined-parameter models of sacroiliac joints (SIJs) MRI relaxometry and peripheral blood Mucosal-associated invariant T (MAIT) cells in evaluating the inflammatory activity of axial spondyloarthritis (axSpA).
METHODS
This retrospective clinical study included 88 axSpA patients (median age 31.0 (22.0, 41.8) years, 21.6% females) and 20 controls (median age 28.0 (20.5, 49.5) years, 40.0% females). The axSpA group was classified into active subgroup (n=50) and inactive subgroup (n=38) based on ASDAS-CRP. All participants underwent SIJs MRI examination including T1 and T2* mapping, and peripheral blood flow cytometry analysis of MAIT cells (defined as CD3Vα7.2CD161) and their activation markers (CD69). The T1 and T2* values, as were the percentages of MAIT cells and CD69MAIT cells were compared between different groups. Combined-parameter models were established using logistic regression, and ROC curves were employed to evaluate the diagnostic efficacy.
RESULTS
The T1 values of SIJs and %CD69MAIT cells in the axSpA group and its subgroup were higher than the control group (p<0.05), while %MAIT cells were lower than the control group (p<0.05). The T1 values and %CD69MAIT cells correlated positively, while %MAIT cells correlated negatively, with the ASDAS-CRP (r=0.555, 0.524, -0.357, p<0.001). Between the control and axSpA groups, and between the inactive and active subgroups, the combined-parameter model T1 mapping+%CD69MAIT cells has the best efficacy (AUC=0.959, 0.879, sensibility=88.6, 70%, specificity=95.0, 94.7%, respectively).
CONCLUSION
The combined-parameter model T1 mapping+%CD69MAIT cells allows a more accurate evaluation of the level of inflammatory activity.
Topics: Humans; Female; Mucosal-Associated Invariant T Cells; Male; Adult; Magnetic Resonance Imaging; Axial Spondyloarthritis; Retrospective Studies; Middle Aged; Young Adult; Sacroiliac Joint; Inflammation; Biomarkers
PubMed: 38840918
DOI: 10.3389/fimmu.2024.1391280 -
Surgical Neurology International 2024Chordomas are rare, locally aggressive neoplasms recognized as derivatives of the notochord vestiges. These tumors typically involve the midline axial skeleton, and...
BACKGROUND
Chordomas are rare, locally aggressive neoplasms recognized as derivatives of the notochord vestiges. These tumors typically involve the midline axial skeleton, and intracranial chordomas exhibit proclivity for the spheno-occipital region. However, purely intrasellar occurrences are extremely rare. We report a case of intrasellar chordoma, which masqueraded as a pituitary neuroendocrine tumor.
CASE DESCRIPTION
An 87-year-old female presented with an acutely altered mental state after a few-week course of headaches and decreased left vision. Adrenal insufficiency was evident, and magnetic resonance imaging revealed an intrasellar lesion with heterogeneous contrast enhancement and marked T2 hyperintensity. Central adrenal insufficiency due to an intrasellar lesion was suspected. Cortisol replacement was initiated, and transsphenoidal surgery was performed. Anterosuperior displacement of the normal pituitary gland and the absence of the bony dorsum sellae were notable during the procedure. Histological examination led to a diagnosis of conventional chordoma, and upfront adjuvant stereotactic radiosurgery was executed. She has been free from tumor progression for 12 months.
CONCLUSION
This case and literature review suggested that the pathognomonic features of intrasellar chordoma were heterogeneous contrast enhancement, marked T2 hyperintensity, osteolytic destruction of the dorsum sellae, and anterosuperior displacement of the pituitary gland. Clinical outcomes seemed slightly worse than those of all skull base chordomas, which were the rationale for upfront radiosurgery in our case. Neurosurgeons should include intrasellar chordomas in the differential diagnosis of intrasellar lesions, carefully dissect them from the adjacent critical anatomical structures, and consider upfront radiosurgery to achieve optimal patient outcomes.
PubMed: 38840611
DOI: 10.25259/SNI_116_2024 -
Ecology and Evolution Jun 2024During mammalian terrestrial locomotion, body flexibility facilitated by the vertebral column is expected to be correlated with observed modes of locomotion, known as...
During mammalian terrestrial locomotion, body flexibility facilitated by the vertebral column is expected to be correlated with observed modes of locomotion, known as gait (e.g., sprawl, trot, hop, bound, gallop). In small- to medium-sized mammals (average weight up to 5 kg), the relationship between locomotive mode and vertebral morphology is largely unexplored. Here we studied the vertebral column from 46 small- to medium-sized mammals. Nine vertebrae across cervical, thoracic, and lumbar regions were chosen to represent the whole vertebral column. Vertebra shape was analysed using three-dimensional geometric morphometrics with the phylogenetic comparative method. We also applied the multi-block method, which can consider all vertebrae as a single structure for analysis. We calculated morphological disparity, phylogenetic signal, and evaluated the effects of allometry and gait on vertebral shape. We also investigated the pattern of integration in the column. We found the cervical vertebrae show the highest degree of morphological disparity, and the first thoracic vertebra shows the highest phylogenetic signal. A significant effect of gait type on vertebrae shape was found, with the lumbar vertebrae having the strongest correlation; but this effect was not significant after taking phylogeny into account. On the other hand, allometry has a significant effect on all vertebrae regardless of the contribution from phylogeny. The regions showed differing degrees of integration, with cervical vertebrae most strongly correlated. With these results, we have revealed novel information that cannot be captured from study of a single vertebra alone: although the lumbar vertebrae are the most correlated with gait, the cervical vertebrae are more morphologically diverse and drive the diversity among species when considering whole column shape.
PubMed: 38835523
DOI: 10.1002/ece3.11478 -
Ideggyogyaszati Szemle May 2024
Parkinson’s disease (PD) is a heterogeneous neurodegenerative disorder characterized by contradictory clinical outcomes among its several subtypes. The disease... (Comparative Study)
Comparative Study
BACKGROUND AND PURPOSE
Parkinson’s disease (PD) is a heterogeneous neurodegenerative disorder characterized by contradictory clinical outcomes among its several subtypes. The disease can manifest with a tremor-dominant (TD) or a non-tremor-dominant (NTD) phenotype. Although the TD subtype may show a better prognosis, there is limited information on the phenotypic differences regarding the level of axial symptoms. For this reason, in this study it was aimed to make a quantitative comparison of axial posture and spinal mobility between PD with TD and NTD.
.METHODS
This case-control study was conducted on 94 patients with diagnosed PD. A group diagnosis approach was used in the study, such that the diagnosis of each patient was confirmed, and they were assig-ned to TD and NTD groups by a neurologist expert on movement disorders. Of the patients with PD, 61 were in the TD group, and 33 were in the NTD group. Spinal mouse was used to measure spinal posture and spinal mobility in both sagittal and frontal planes.
.RESULTS
Two groups of 61 patients (25 male + 36 female) with TD-PD (mean age: 64.49±10.37 years) and 33 patients (20 male +13 female) with NTD-PD (mean age: 63.45±9.11 years) were enrolled in the study. There were no significant differences between the patients with TD and NTD in terms of sagittal and frontal postures (p>0.05). In addition to this, anterior trunk tilt was found to significantly increase as the disease stage advanced in both groups. While the greatest anterior trunk tilt change in the TD-PD group was observed in the 3rd stage, NTD-PD group was in the 2.5th stage. Aside from this, the outcomes of the spinal mobility measurements in the frontal and sagittal planes were similar between the groups (p>0.05).
.CONCLUSION
It is widely acknowledged that many clinical aspects of the TD and NTD forms of PD differ; however, in our study, it was observed that there may be no difference in the axial symptoms of the patients with PD in terms of classification according to tremor dominance.
.Topics: Humans; Parkinson Disease; Posture; Female; Male; Middle Aged; Case-Control Studies; Aged; Spine; Tremor
PubMed: 38829249
DOI: 10.18071/isz.77.0187 -
BMC Musculoskeletal Disorders Jun 2024To develop an AI-assisted MRI model to identify surgical target areas in pediatric hip and periarticular infections.
OBJECTIVE
To develop an AI-assisted MRI model to identify surgical target areas in pediatric hip and periarticular infections.
METHODS
A retrospective study was conducted on the pediatric patients with hip and periarticular infections who underwent Magnetic Resonance Imaging(MRI)examinations from January 2010 to January 2023 in three hospitals in China. A total of 7970 axial Short Tau Inversion Recovery (STIR) images were selected, and the corresponding regions of osteomyelitis (label 1) and abscess (label 2) were labeled using the Labelme software. The images were randomly divided into training group, validation group, and test group at a ratio of 7:2:1. A Mask R-CNN model was constructed and optimized, and the performance of identifying label 1 and label 2 was evaluated using receiver operating characteristic (ROC) curves. Calculation of the average time it took for the model and specialists to process an image in the test group. Comparison of the accuracy of the model in the interpretation of MRI images with four orthopaedic surgeons, with statistical significance set at P < 0.05.
RESULTS
A total of 275 patients were enrolled, comprising 197 males and 78 females, with an average age of 7.10 ± 3.59 years, ranging from 0.00 to 14.00 years. The area under curve (AUC), accuracy, sensitivity, specificity, precision, and F1 score for the model to identify label 1 were 0.810, 0.976, 0.995, 0.969, 0.922, and 0.957, respectively. The AUC, accuracy, sensitivity, specificity, precision, and F1 score for the model to identify label 2 were 0.890, 0.957, 0.969, 0.915, 0.976, and 0.972, respectively. The model demonstrated a significant speed advantage, taking only 0.2 s to process an image compared to average 10 s required by the specialists. The model identified osteomyelitis with an accuracy of 0.976 and abscess with an accuracy of 0.957, both statistically better than the four orthopaedic surgeons, P < 0.05.
CONCLUSION
The Mask R-CNN model is reliable for identifying surgical target areas in pediatric hip and periarticular infections, offering a more convenient and rapid option. It can assist unexperienced physicians in pre-treatment assessments, reducing the risk of missed and misdiagnosis.
Topics: Humans; Male; Female; Magnetic Resonance Imaging; Child; Retrospective Studies; Adolescent; Osteomyelitis; Child, Preschool; Infant; Hip Joint; China; Abscess; ROC Curve
PubMed: 38824518
DOI: 10.1186/s12891-024-07548-1 -
BMC Musculoskeletal Disorders May 2024The morphology of coxa profunda remains inadequately understood. However, knowledge about the characteristics of the acetabulum in coxa profunda can help to predict... (Observational Study)
Observational Study
BACKGROUND
The morphology of coxa profunda remains inadequately understood. However, knowledge about the characteristics of the acetabulum in coxa profunda can help to predict pelvic morphology in three dimensions based on radiographic findings, as well as help to diagnose and predict hip pathologies. Therefore, this study aimed to investigate the relationship between the morphological characteristics of the pelvis and coxa profunda.
METHODS
We conducted a retrospective analysis including women who had undergone unilateral total hip arthroplasty. Only those with normal hip joint morphology on the opposite side, as evidenced by anteroposterior pelvic radiography showing a distance of ≥ 2 mm between the ilioischial line and acetabular floor, were included. Five parameters related to acetabular anteversion, thickness, and the position of the ilioischial line were measured using axial computed tomography at the central hip joint. The coxa profunda group (n = 39) and control group (n = 34) were compared.
RESULTS
The mean acetabular anteversion angle was 12.5° ± 4° in the control group and 22.3° ± 5.6° in the coxa profunda group. The mean thickness from the acetabular fossa to the medial wall was 7.5 ± 1.7 mm in the control group and 3.9 ± 1.2 mm in the coxa profunda group. Furthermore, the bony region representing the ilioischial line was positioned more posteriorly in the coxa profunda group than it was in the control group.
CONCLUSION
Our findings suggest that coxa profunda in women is associated with anterior acetabular dysplasia and a thin acetabulum, in contrast to previous interpretations of excessive coverage. This insight suggests a conversion of coxa profunda from a finding of pincer-type femoroacetabular impingement to a finding of acetabular dysplasia, a revelation that also draws attention to cup positioning for total hip arthroplasty.
Topics: Humans; Female; Acetabulum; Retrospective Studies; Middle Aged; Aged; Tomography, X-Ray Computed; Arthroplasty, Replacement, Hip; Hip Joint; Adult
PubMed: 38822289
DOI: 10.1186/s12891-024-07540-9