-
European Journal of Radiology Sep 2022To describe the findings of focal high signal on T2 weighted (T2W) images of the bone marrow in the axial skeleton as assessed by whole-body MRI in healthy and...
OBJECTIVE
To describe the findings of focal high signal on T2 weighted (T2W) images of the bone marrow in the axial skeleton as assessed by whole-body MRI in healthy and asymptomatic children and adolescents.
MATERIAL AND METHODS
We assessed the bone marrow of the mandible, shoulder girdle, thorax, spine, and pelvis on water-only Dixon T2W sequences as part of a whole-body MRI protocol in 196 healthy and asymptomatic children aged 5-19 years. Intensity (0-2 scale) and extension (1-4 scale) of focal high signal areas in the bone marrow were scored and divided into minor or major findings, based on intensity and extension to identify the potentially conspicuous lesions in a clinical setting.
RESULTS
We registered 415 areas of increased signal in the axial skeleton whereof 75 (38.3%) were major findings. Fifty-eight (29.6%) individuals had at least one major finding, mainly located in the pelvis (54, 72%). We found no differences according to gender. The number of minor findings increased with age (p = 0.020), but there were no significant differences in the number of major findings. The most conspicuous findings were in the pelvis, spine and sternum.
CONCLUSION
Non-specific bone marrow T2W hyperintensities in the axial skeleton are frequently detected on whole-body MRI in healthy, asymptomatic children. Awareness of this is important as some findings may resemble clinically silent lesions in children with suspected multifocal skeletal disease.
Topics: Adolescent; Bone Marrow; Bone and Bones; Child; Humans; Magnetic Resonance Imaging; Thorax; Whole Body Imaging
PubMed: 35843014
DOI: 10.1016/j.ejrad.2022.110425 -
Neurosurgical Review Aug 2021Rheumatoid arthritis (RA) is a progressive autoimmune inflammatory disease affecting 1% of the population with three times as many women as men. As many as 86% of... (Review)
Review
Rheumatoid arthritis (RA) is a progressive autoimmune inflammatory disease affecting 1% of the population with three times as many women as men. As many as 86% of patients suffering from RA have cervical spine involvement. Synovial inflammation in the cervical spine causes instability and injuries including atlantoaxial subluxation, retroodontoid pannus formation, cranial settling, and subaxial subluxation. While many patients with cervical spine involvement are asymptomatic, symptomatic patients often present with nonspecific symptoms resulting from inflammation and additional secondary symptoms that are due to compression of the brainstem, cranial nerves, vertebral artery, and spinal cord. Radiographs are the imaging modality used most often, while MRI and CT are used for assessment of neural element involvement and surgical planning. Multiple classification systems exist. Early diagnosis and treatment of cervical spine involvement is critical. Surgical management is indicated when patients experience symptoms from cervical involvement that result in biomechanical instability and, or a neurological deficit. Atlantoaxial instability managed with atlantoaxial fusion, retroodontoid pannus with neural element compression is managed with posterior decompression and atlantoaxial fusion or occipitocervical fusion. Cranial settling is managed can be managed with anterior decompression and posterior fusion or with dorsal only approaches. Subaxial subluxation is managed with circumferential fusion or posterior only decompression and fusion. Patients with atlantoaxial instability have better functional and neurologic outcomes. RA patients have higher complication rates and more frequent need for revision surgery than the general population of spine surgery patients.
Topics: Arthritis, Rheumatoid; Atlanto-Axial Joint; Cervical Vertebrae; Female; Humans; Joint Dislocations; Male; Spinal Fusion
PubMed: 33037539
DOI: 10.1007/s10143-020-01412-1 -
Skeletal Radiology Jun 2022Hibernomas are rare lipomatous tumors composed of brown adipocytes. The relative paucity of reported cases involving the bones accounts for the poor understanding of...
Hibernomas are rare lipomatous tumors composed of brown adipocytes. The relative paucity of reported cases involving the bones accounts for the poor understanding of this entity, which is known to affect almost exclusively the axial skeleton. We present a case of intraosseous hibernoma of the humerus, which was found incidentally in a 52-year-old woman and initially misinterpreted as a cartilaginous tumor on magnetic resonance imaging (MRI). The lesion was unchanged in size and morphology at short interval follow-up but increased in size during follow-up over 6 years with an 11 mm increase in the largest diameter. Given the patient's concerns and lesion growth, curettage was performed. Pathology analysis revealed brown fat in keeping with the diagnosis of intraosseous hibernoma. Radiological and pathological findings and pitfalls are herein highlighted to enforce knowledge on this lesion rarely affecting the long bones. Radiologists should think of intraosseous hibernoma if they come across a sclerotic lesion on X-ray or computed tomography, which contains macroscopic fat and shows enhancement on contrast-enhanced MRI. In addition, an intraosseous hibernoma may be picked up incidentally on positron emission tomography-computed tomography due to high fluorodeoxyglucose avidity.
Topics: Adipose Tissue, Brown; Diagnosis, Differential; Female; Fluorodeoxyglucose F18; Humans; Humerus; Lipoma; Middle Aged
PubMed: 34779887
DOI: 10.1007/s00256-021-03956-9 -
Differentiation; Research in Biological... 2022The cervical and anterior thoracic regions of mammals generally exhibit similar vertebral numbers and identities along the anterior-posterior axis. The position of the...
The cervical and anterior thoracic regions of mammals generally exhibit similar vertebral numbers and identities along the anterior-posterior axis. The position of the forelimbs along the axial skeleton is also generally conserved. In contrast, the number of lumbar and sacral vertebrae and pelvic position exhibit more variation, correlating with posture and locomotion. The molecular mechanisms that lead to these conserved and variable axial skeletal patterns between species are not fully understood. Here we use a human HOXB1-9 transgene to complement a HoxB1-9 deficiency in the mouse. In TgHOXB1-9 mice, human HOXB1, B2, B3, and B4 (HOXB1-4) genes were expressed in mouse embryos in patterns similar to mouse Hoxb1-4 genes. Human transgene expression rescued the cervical and anterior thoracic vertebral patterning defects of HoxB1-9 mice. In addition, the posterior shift in forelimb position of HoxB1-9 mice was rescued by the transgene. Interestingly, the position of the lumbar-sacral transition in both TgHOXB1-9; HoxB1-9 and TgHOXB1-9; HoxB1-9 mice was altered from six lumbar and four sacral vertebrae found in wild-type controls to five lumbar and five sacral vertebrae. The change in the position of the lumbar-sacral transition consequently altered the position of the pelvis. In contrast to the conserved expression of human HOXB1-4 genes in TgHOXB1-9 mouse embryos, the anterior border of human HOXB9 expression in the neural tube and paraxial mesoderm was shifted posteriorly by 2-3 somites compared to the anterior boundary of endogenous Hoxb9 expression. These findings suggest that conservation and variation in Hoxb/HOXB expression contributes to conserved and species-specific vertebral pattern and limb position.
Topics: Animals; Bone and Bones; Gene Expression Regulation, Developmental; Genes, Homeobox; Homeodomain Proteins; Humans; Mammals; Mice; Mice, Transgenic; Somites; Spine; Transcription Factors
PubMed: 36041259
DOI: 10.1016/j.diff.2022.07.002 -
PloS One 2022Different hip pathologies can cause geometric variation of the acetabulum and femoral head. These variations have been considered as an underlying mechanism that affects...
Different hip pathologies can cause geometric variation of the acetabulum and femoral head. These variations have been considered as an underlying mechanism that affects the tribology of the natural hip joint and changes the stress distribution on the articular surface, potentially leading to joint degradation. To improve understanding of the damage mechanisms and abnormal mechanics of the hip joint, a reliable in-vitro methodology that represents the in vivo mechanical environment is needed where the position of the joint, the congruency of the bones and the loading and motion conditions are clinically relevant and can be modified in a controlled environment. An in vitro simulation methodology was developed and used to assess the effect of loading on a natural hip joint. Porcine hips were dissected and mounted in a single station hip simulator and tested under different loading scenarios. The loading and motion cycle consisted of a simplified gait cycle and three peak axial loading conditions were assessed (Normal, Overload and Overload Plus). Joints were lubricated with Ringer's solution and tests were conducted for 4 hours. Photographs were taken and compared to characterise cartilage surface and labral tissue pre, during and post simulation. The results showed no evidence of damage to samples tested under normal loading conditions, whereas the samples tested under overload and overload plus conditions exhibited different severities of tears and detachment of the labrum at the antero-superior region. The location and severity of damage was consistent for samples tested under the same conditions; supporting the use of this methodology to investigate further effects of altered loading and motion on natural tissue.
Topics: Acetabulum; Animals; Cartilage, Articular; Femur Head; Hip Joint; Swine; Weight-Bearing
PubMed: 35980907
DOI: 10.1371/journal.pone.0272264 -
Journal of Biomechanical Engineering May 2023Axial tibial rotation is a characteristic motion of the knee, but how it occurs with knee flexion is controversial. We investigated the mechanisms of tibial rotations by...
Axial tibial rotation is a characteristic motion of the knee, but how it occurs with knee flexion is controversial. We investigated the mechanisms of tibial rotations by analyzing in vivo tibiofemoral articulations. Twenty knees of 20 living human subjects were investigated during a weightbearing flexion from full extension to maximal flexion using a dual fluoroscopic imaging system. Tibiofemoral articular contact motions on medial and lateral femoral condyles and tibial surfaces were measured at flexion intervals of 15 deg from 0 deg to 120 deg. Axial tibial rotations due to the femoral and tibial articular motions were compared. Articular contact distances were longer on femoral condyles than on tibial surfaces at all flexion intervals (p < 0.05). The articular distance on medial femoral condyle is longer than on lateral side during flexion up to 60 deg. The internal tibial rotation was 6.8 ± 4.5 deg (Mean ± SD) at the flexion interval of 0-15 deg, where 6.1 ± 2.6 deg was due to articulations on femoral condyles and 0.7 ± 5.1 deg due to articulations on tibial surfaces (p < 0.05). The axial tibial rotations due to articulations on femoral condyles are significantly larger than those on tibial surfaces until 60 deg of flexion (p < 0.05). Minimal additional axial tibial rotations were observed beyond 60 deg of flexion. The axial tibial rotations were mainly attributed to uneven articulations on medial and lateral femoral condyles. These data can provide new insights into the understanding of mechanisms of axial tibial rotations and serve as baseline knowledge for improvement of knee surgeries.
Topics: Humans; Biomechanical Phenomena; Knee Joint; Tibia; Femur; Range of Motion, Articular; Weight-Bearing; Rotation; Knee Prosthesis
PubMed: 36477949
DOI: 10.1115/1.4056431 -
Journal of Biomechanics May 2022Glenohumeral and scapulothoracic motion combine to generate humerothoracic motion, but their discrete contributions towards humerothoracic axial rotation have not been...
Glenohumeral and scapulothoracic motion combine to generate humerothoracic motion, but their discrete contributions towards humerothoracic axial rotation have not been investigated. Understanding their contributions to axial rotation is important to judge the effects of pathology, surgical intervention, and physiotherapy. Therefore, the purpose of this study was to investigate the kinematic coupling between glenohumeral and scapulothoracic motion and determine their relative contributions towards axial rotation. Twenty healthy subjects (10 M/10F, ages 22-66) were previously recorded using biplane fluoroscopy while performing arm elevation in the coronal, scapular, and sagittal planes, and external rotation in 0° and 90° of abduction. Glenohumeral and scapulothoracic contributions towards axial rotation were computed by integrating the projection of glenohumeral and scapulothoracic angular velocity onto the humeral longitudinal axis, and analyzed using one dimensional statistical parametric mapping and linear regression. During arm elevation, scapulothoracic motion supplied 13-20° (76-94%) of axial rotation, mainly via scapulothoracic upward rotation. The contribution of scapulothoracic motion towards axial rotation was strongly correlated with glenohumeral plane of elevation during arm elevation. During external rotation, scapulothoracic motion contributed 10° (8%) towards axial rotation in 0° of abduction and 15° (15%) in 90° of abduction. The contribution of scapulothoracic motion towards humerothoracic axial rotation could explain the simultaneous changes in glenohumeral plane of elevation and axial rotation associated with some pathologies and surgeries. Understanding how humerothoracic motion results from the functional coupling of scapulothoracic and glenohumeral motions may inform diagnostic and treatment strategies by targeting the source of movement impairments in clinical populations.
Topics: Adult; Aged; Biomechanical Phenomena; Humans; Humerus; Middle Aged; Range of Motion, Articular; Rotation; Scapula; Shoulder Joint; Young Adult
PubMed: 35367838
DOI: 10.1016/j.jbiomech.2022.111059 -
Anatomical Record (Hoboken, N.J. : 2007) Jul 2022Captive specimens in museum collections facilitate study of rare taxa, but the lifestyles, diets, and lifespans of captive animals differ from their wild counterparts....
Captive specimens in museum collections facilitate study of rare taxa, but the lifestyles, diets, and lifespans of captive animals differ from their wild counterparts. Trabecular bone architecture adapts to in vivo forces, and may reflect interspecific variation in ecology and behavior as well as intraspecific variation between captive and wild specimens. We compared trunk vertebrae bone microstructure in captive and wild xenarthran mammals to test the effects of ecology and captivity. We collected μCT scans of the last six presacral vertebrae in 13 fossorial, terrestrial, and suspensorial xenarthran species (body mass: 120 g to 35 kg). For each vertebra, we measured centrum length; bone volume fraction (BV.TV); trabecular number and mean thickness (Tb.Th); global compactness (GC); cross-sectional area; mean intercept length; star length distribution; and connectivity and connectivity density. Wild specimens have more robust trabeculae, but this varies with species, ecology, and pathology. Wild specimens of fossorial taxa (Dasypus) have more robust trabeculae than captives, but there is no clear difference in bone microstructure between wild and captive specimens of suspensorial taxa (Bradypus, Choloepus), suggesting that locomotor ecology influences the degree to which captivity affects bone microstructure. Captive Tamandua and Myrmecophaga have higher BV.TV, Tb.Th, and GC than their wild counterparts due to captivity-caused bone pathologies. Our results add to the understanding of variation in mammalian bone microstructure, suggest caution when including captive specimens in bone microstructure research, and indicate the need to better replicate the habitats, diets, and behavior of animals in captivity.
Topics: Animals; Bone Density; Bone and Bones; Mammals; Spine
PubMed: 34677912
DOI: 10.1002/ar.24817 -
Current Rheumatology Reports May 2020Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting mainly the peripheral skeleton in a symmetrical manner rather than the axial skeleton, but when it... (Review)
Review
PURPOSE OF REVIEW
Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting mainly the peripheral skeleton in a symmetrical manner rather than the axial skeleton, but when it occurs it can affect the cervical spine (CS). Although CS involvement is a frequent radiographic finding in RA, the clinical features are scarce, but potentially life-threatening with severe neurological deficits or even death due to brain stem compression. The commonest site of inflammation of the CS is the articulation between C and C vertebrae, the atlanto-axial region. The radiological finding observed in this region is the atlanto-axial subluxation (AAS). For the evaluation of CS in RA the classical diagnostic technique used mostly is conventional radiography (CR). Since CR does not provide good information regarding synovial inflammation, other imaging modalities are used such as magnetic resonance imaging and computed tomography. However, CR is the most valuable tool for screening CS in RA patients. Thus, we reviewed the literature until December 2019 for studies regarding CS radiological manifestations using CR in RA patients.
RECENT FINDINGS
We found that the frequency of radiological findings varies substantially, ranging between 0.7-95% in different studies. The commonest radiological feature was the AAS followed by subaxial subluxation. Because CS involvement can often be clinically asymptomatic, its assessment should not be forgotten by physicians and should be assessed using CR which is an easy to perform technique and gives important information as a screening tool.
Topics: Arthritis, Rheumatoid; Cervical Vertebrae; Humans; Magnetic Resonance Imaging; Radiography; Rheumatologists
PubMed: 32405896
DOI: 10.1007/s11926-020-00894-8 -
Journal of Pediatric Orthopedics 2020This study aimed to evaluate the long-term clinical and radiologic follow-up results of eosinophilic granulomas (EGs) of the axial and appendicular skeleton managed with...
BACKGROUND
This study aimed to evaluate the long-term clinical and radiologic follow-up results of eosinophilic granulomas (EGs) of the axial and appendicular skeleton managed with biopsy alone.
METHODS
Fifty-five patients with unifocal osseous EGs of the axial and appendicular skeleton were followed after biopsy. Patients were divided into 2 groups on the basis of localization of the lesions. In group 1, there were 32 (58.2%) children with extremity long bone involvement: femur, tibia, humerus, ulna, and radius. Group 2 included 23 (41.8%) patients with lesions located in other appendicular and axial skeleton bones: pelvis, scapula, clavicle, lumbar, and thoracic vertebrae. After confirming the diagnosis by a closed biopsy, no further surgical intervention was performed. Clinical recovery included regression of the localized symptoms, mainly pain resolution. Functional improvement was assessed by Musculoskeletal Tumor Society (MSTS) scoring. Radiologic healing was defined as ossification of the entire lesion with cortical thickening in long and flat bones, and restoration of vertebral body height in the spine. Complications, including local recurrence, were determined.
RESULTS
The patients comprised 28 boys and 27 girls with an average age of 9.2 years (range, 3 to 16 y). The average follow-up was 76 months (range, 28 to 132 mo). The median time from biopsy to clinical recovery was 17 days [95% confidence interval (CI), 13.3-20.6] and 36 days (95% Cl, 32.8-39.1) in group 1 and group 2, respectively. MSTS scores increased progressively till the end of 12 months in both groups. The median time from biopsy to radiologic healing was 16 months (95% CI, 11.5-20.4) and 42 months (95% Cl, 39.3-44.6) in group 1 and group 2, respectively. Both clinical recovery (P=0.021) and radiologic healing (P=0.009) were significantly faster in group 1 compared with group 2. No major complication was seen after biopsy. All lesions regressed without a local recurrence.
CONCLUSIONS
Unifocal osseous EGs have spontaneous healing potential and confirming the diagnosis by biopsy is enough to obtain good clinical and radiologic results without any additional surgical intervention.
TYPE OF STUDY
This was a therapeutic study.
LEVEL OF EVIDENCE
Level IV.
Topics: Adolescent; Bone and Bones; Child; Child, Preschool; Eosinophilic Granuloma; Female; Follow-Up Studies; Humans; Male; Radiography; Recovery of Function; Retrospective Studies; Turkey
PubMed: 32558743
DOI: 10.1097/BPO.0000000000001612