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Thornton R, Mendelow MG, Hutchinson EF. Assessing the morphology and bone mineral density of the immature pars lateralis as an indicator of age. Int J Legal Med 2024; 138:467-486. [PMID: 37775592 PMCID: PMC10861619 DOI: 10.1007/s00414-023-03085-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/09/2023] [Indexed: 10/01/2023]
Abstract
Age estimation is crucial when the state of personhood is a mitigating factor in the identification of immature human remains. The maturation sequence of immature bones is a valuable alternative to dental development and eruption standards. Bordering the foramen magnum and pars basilaris, the pars lateralis is somewhat understudied. The aim of this study was to comprehensively describe the morphology of the immature human pars lateralis bone. Human pars laterali were sourced from the crania of 103 immature individuals of unknown provenance from the Johannesburg Forensic Paediatric Collection (JFPC), University of the Witwatersrand (HREC-Medical: M210855). The study sample was subdivided into early prenatal (younger than 30 gestational weeks; n = 32), prenatal (30-40 gestational weeks, n = 41) and postnatal (birth to 7.5 months, n = 30) age groups. The morphology of the pars laterali was studied using a combination of bone mineral density pattern assessments, geometric morphometrics and stereomicroscopy. Bone mineral density in postnatal individuals was lower when compared with the prenatal individuals. No statistically significant differences between density points were noted. The overall shape of the pars lateralis changed from a triangular shape in the early prenatal individuals to a fan-like quadrilateral bone in postnatal individuals. The angulation of the medial border for the foramen magnum highlighted a change in shape between straight in the early prenatal cohort to V-shaped in the postnatal individuals. The various technical approaches used in the current study provided detailed descriptions of the pars lateralis which establishes a valuable foundation for diagnostic criteria employing morphological predictors for biological profiling.
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Affiliation(s)
- Roxanne Thornton
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Mira G Mendelow
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Erin F Hutchinson
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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2
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Wei X, Cooper DML. The various meanings and uses of bone "remodeling" in biological anthropology: A review. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023; 182:318-329. [PMID: 37515465 DOI: 10.1002/ajpa.24825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/28/2023] [Accepted: 07/09/2023] [Indexed: 07/30/2023]
Abstract
OBJECTIVES In modern bone biology, the term "remodeling" generally refers to internal bone turnover that creates secondary osteons. However, it is also widely used by skeletal biologists, including biological anthropologists as a catch-all term to refer to different skeletal changes. In this review, we investigated how "remodeling" is used across topics on skeletal biology in biological anthropology to demonstrate potential problems with such pervasive use of a generalized term. METHODS Using PubMed and Google Scholar, we selected and reviewed 205 articles that use the term remodeling to describe skeletal processes and have anthropological implications. Nine edited volumes were also reviewed as examples of collaborative work by different experts to demonstrate the diverse and extensive use of the term remodeling. RESULTS Four general meanings of bone "remodeling" were identified, namely, internal turnover, functional adaptation, fracture repair, and growth remodeling. Additionally, remodeling is also used to refer to a broad array of pathological skeletal changes. DISCUSSION Although we initially identified four general meanings of bone remodeling, they are not mutually exclusive and often occur in combination. The term "remodeling" has become an extensively used catch-all term to refer to different processes and outcomes of skeletal changes, which inevitably lead to misunderstanding and a loss of information. Such ambiguity and confusion are potentially problematic as the field of biological anthropology becomes increasingly multidisciplinary. Therefore, we advocate for precise, context-specific definitions and explanations of bone remodeling as it continues to be used across disciplines within and beyond biological anthropology.
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Affiliation(s)
- Xuan Wei
- Department of Anatomy, Physiology, and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - David M L Cooper
- Department of Anatomy, Physiology, and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Brachetta-Aporta N, Gonzalez PN, Bernal V. Association between shape changes and bone remodeling patterns in the middle face during ontogeny in South American populations. Anat Rec (Hoboken) 2021; 305:156-169. [PMID: 33844463 DOI: 10.1002/ar.24640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/17/2021] [Accepted: 03/19/2021] [Indexed: 11/10/2022]
Abstract
The morphology of facial bones is modeled by processes of bone formation and resorption induced by interactions between tissues and compensatory responses. However, the role of remodeling patterns on the morphological changes within and among populations has been scarcely explored. Here, we assess the association between facial shape and the underlying bone cell activity throughout the ontogeny in two Amerindian populations that represent the extremes of craniofacial variation in South America. The sample comprises 71 individuals (36 adults and 35 subadults) representing hunter-gatherers from Patagonia and horticulturists from Northwest Argentina. We analyzed the shape and size of the zygomatic and the maxilla, and compared them with the patterns of bone formation and resorption. Bone formation and resorption were described by quantitative histological analysis of bone surfaces. Morphological changes were described by landmarks and semilandmarks digitized on 3D surfaces obtained from CT images. The results from multivariate statistics analysis show that the patterns of bone remodeling are associated with variation in the morphology of the middle face. We found a similar pattern of facial shape variation along the ontogenetic trajectory in the two samples, and a similar trend in the amount of formation and resorption activities across ages. The main differences between samples were found in the distribution of the areas of bone formation and resorption, possibly associated with mechanical bone response to masticatory loading. These findings provide clues about the processes and mechanisms of bone development involved in the facial morphological differentiation in human populations from southern South America.
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Affiliation(s)
- Natalia Brachetta-Aporta
- IIPG, Instituto de Investigaciones en Paleobiología y Geología, Río Negro, Argentina.,UNRN, Universidad Nacional de Río Negro. CONICET, Río Negro, Argentina
| | - Paula N Gonzalez
- ENyS. Estudios en Neurociencias y Sistemas Complejos, Buenos Aires, Argentina
| | - Valeria Bernal
- División Antropología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. CONICET, La Plata, Argentina
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Ramos-Dávila EM, Meléndez-Flores JD, Álvarez-Pérez R, Barrera-Flores FJ, Martínez-Cobos MC, Pinales-Razo R, Quiroga-Garza A, Zarate-Garza P, Sanchez-Gomez A, Guzman-Lopez S, Elizondo-Omaña RE. Occipital condyle screw fixation viability according to age and gender anatomy: A computed tomography-based analysis. Clin Neurol Neurosurg 2020; 200:106358. [PMID: 33223342 DOI: 10.1016/j.clineuro.2020.106358] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To assess the Occipital condyle morphology in an all-age population of Northeastern Mexico, and determine age and gender related changes for surgical viability. METHODS A total of 175 consecutive HRCT scans were included and divided into 5 age groups. The condylar length, width, height, sagittal angle, anterior, posterior and medial intercondylar distances, and intercondylar angle of the OC were measured. RESULTS Mean condylar length, width, and height in total population were 20.58 mm, 9.42 mm, and 9.02 mm, respectively. Differences were observed in most morphometric parameters when comparing age groups. Significant intergender differences in total population were observed in most parameters, when individualizing each age group the height remained significant in all. The group with the least height measurement was aged 5-9 years, this however, could allow the OC screw (≥6.5 mm) placement. CONCLUSION Differences in most morphometric parameters of OC were observed between age groups and gender, particularly patients with 5-9 years. However, all groups presented a minimum height that allows the placement of a standard screw. A preoperative imaging study is always recommended due to the variability and complexity of the region.
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Affiliation(s)
| | | | - Ricardo Álvarez-Pérez
- Universidad Autónoma de Nuevo León, Facultad de Medicina, Hospital Universitario "Dr. José Eleuterio González", Department of Radiology and Imaging, Monterrey, Mexico.
| | | | - Maria C Martínez-Cobos
- Universidad Autónoma de Nuevo León, Facultad de Medicina, Hospital Universitario "Dr. José Eleuterio González", Department of Radiology and Imaging, Monterrey, Mexico.
| | - Ricardo Pinales-Razo
- Universidad Autónoma de Nuevo León, Facultad de Medicina, Hospital Universitario "Dr. José Eleuterio González", Department of Radiology and Imaging, Monterrey, Mexico.
| | | | - Patricio Zarate-Garza
- Human Anatomy Department, Faculty of Medicine, Universidad Autónoma, Monterrey, Mexico.
| | - Arnulfo Sanchez-Gomez
- Human Anatomy Department, Faculty of Medicine, Universidad Autónoma, Monterrey, Mexico.
| | - Santos Guzman-Lopez
- Human Anatomy Department, Faculty of Medicine, Universidad Autónoma, Monterrey, Mexico.
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Schuh A, Kupczik K, Gunz P, Hublin J, Freidline SE. Ontogeny of the human maxilla: a study of intra-population variability combining surface bone histology and geometric morphometrics. J Anat 2019; 235:233-245. [PMID: 31070788 PMCID: PMC6637443 DOI: 10.1111/joa.13002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2019] [Indexed: 01/21/2023] Open
Abstract
Bone modeling is the process by which bone grows in size and models its shape via the cellular activities of the osteoblasts and osteoclasts that respectively form and remove bone. The patterns of expression of these two activities, visible on bone surfaces, are poorly understood during facial ontogeny in Homo sapiens; this is due mainly to small sample sizes and a lack of quantitative data. Furthermore, how microscopic activities are related to the development of morphological features, like the uniquely human-canine fossa, has been rarely explored. We developed novel techniques for quantifying and visualizing variability in bone modeling patterns and applied these methods to the human maxilla to better understand its development at the micro- and macroscopic levels. We used a cross-sectional ontogenetic series of 47 skulls of known calendar age, ranging from birth to 12 years, from a population of European ancestry. Surface histology was employed to record and quantify formation and resorption on the maxilla, and digital maps representing each individual's bone modeling patterns were created. Semilandmark geometric morphometric (GM) methods and multivariate statistics were used to analyze facial growth. Our results demonstrate that surface histology and GM methods give complementary results, and can be used as an integrative approach in ontogenetic studies. The bone modeling patterns specific to our sample are expressed early in ontogeny, and fairly constant through time. Bone resorption varies in the size of its fields, but not in location. Consequently, absence of bone resorption in extinct species with small sample sizes should be interpreted with caution. At the macroscopic level, maxillary growth is predominant in the top half of the bone where bone formation is mostly present. Our results suggest that maxillary growth in humans is highly constrained from early stages in ontogeny, and morphological changes are likely driven by changes in osteoblastic and osteoclastic rates of expression rather than differences in the bone modeling patterns (i.e. changes in location of formation and resorption). Finally, the results of the micro- and macroscopic analyses suggest that the development of the canine fossa results from a combination of bone resorption and bone growth in the surrounding region.
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Affiliation(s)
- Alexandra Schuh
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Kornelius Kupczik
- Max Planck Weizmann Center for Integrative Archaeology and AnthropologyMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Philipp Gunz
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Jean‐Jacques Hublin
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Sarah E. Freidline
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
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Brachetta‐Aporta N, Gonzalez PN, Bernal V. Variation in facial bone growth remodeling in prehistoric populations from southern South America. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:422-434. [DOI: 10.1002/ajpa.23857] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/01/2019] [Accepted: 05/06/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Natalia Brachetta‐Aporta
- Facultad de Ciencias Naturales y Museo, División AntropologíaUniversidad Nacional de La Plata, CONICET La Plata Argentina
| | - Paula N. Gonzalez
- Facultad de Ciencias Naturales y Museo, División AntropologíaUniversidad Nacional de La Plata, CONICET La Plata Argentina
- Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos (CONICET‐HEC‐UNAJ) Buenos Aires Argentina
| | - Valeria Bernal
- Facultad de Ciencias Naturales y Museo, División AntropologíaUniversidad Nacional de La Plata, CONICET La Plata Argentina
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Rosas A, Ríos L, Estalrrich A, Liversidge H, García-Tabernero A, Huguet R, Cardoso H, Bastir M, Lalueza-Fox C, de la Rasilla M, Dean C. The growth pattern of Neandertals, reconstructed from a juvenile skeleton from El Sidrón (Spain). Science 2018; 357:1282-1287. [PMID: 28935804 DOI: 10.1126/science.aan6463] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 07/27/2017] [Indexed: 11/02/2022]
Abstract
Ontogenetic studies help us understand the processes of evolutionary change. Previous studies on Neandertals have focused mainly on dental development and inferred an accelerated pace of general growth. We report on a juvenile partial skeleton (El Sidrón J1) preserving cranio-dental and postcranial remains. We used dental histology to estimate the age at death to be 7.7 years. Maturation of most elements fell within the expected range of modern humans at this age. The exceptions were the atlas and mid-thoracic vertebrae, which remained at the 5- to 6-year stage of development. Furthermore, endocranial features suggest that brain growth was not yet completed. The vertebral maturation pattern and extended brain growth most likely reflect Neandertal physiology and ontogenetic energy constraints rather than any fundamental difference in the overall pace of growth in this extinct human.
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Affiliation(s)
- Antonio Rosas
- Paleoanthropology Group, Department of Paleobiology, Museo Nacional de Ciencias Naturales (MNCN)-Consejo Superior de Investigaciones Científicas (CSIC), Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain.
| | - Luis Ríos
- Paleoanthropology Group, Department of Paleobiology, Museo Nacional de Ciencias Naturales (MNCN)-Consejo Superior de Investigaciones Científicas (CSIC), Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain.,Department of Physical Anthropology, Aranzadi Society of Sciences, Zorroagagaina 11, 20014 Donostia-San Sebastián, Gipuzkoa, Spain
| | - Almudena Estalrrich
- Paleoanthropology Group, Department of Paleobiology, Museo Nacional de Ciencias Naturales (MNCN)-Consejo Superior de Investigaciones Científicas (CSIC), Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain.,Department of Paleoanthropology, Senckenberg Research Institute and Natural History Museum Frankfurt, Senckenberganlage 25, 60325 Franckfurta, Germany
| | - Helen Liversidge
- Queen Mary University of London, Institute of Dentistry, Turner Street, London E1 2AD, UK
| | - Antonio García-Tabernero
- Paleoanthropology Group, Department of Paleobiology, Museo Nacional de Ciencias Naturales (MNCN)-Consejo Superior de Investigaciones Científicas (CSIC), Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Rosa Huguet
- Institut Català de Paleoecologia Humana i Evolució Social-Unidad Asociada al CSIC, Campus Sescelades (Edifici W3), Universitat Rovira i Virgili, Carrer Marcel.lí Domingo s/n, 43007 Tarragona, Spain
| | - Hugo Cardoso
- Department of Archaeology, Simon Fraser University, Burnaby, British Columbia V5A1S6, Canada
| | - Markus Bastir
- Paleoanthropology Group, Department of Paleobiology, Museo Nacional de Ciencias Naturales (MNCN)-Consejo Superior de Investigaciones Científicas (CSIC), Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Carles Lalueza-Fox
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Carrer Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Marco de la Rasilla
- Área de Prehistoria Departamento de Historia, Universidad de Oviedo, Calle Teniente Alfonso Martínez s/n, 33011 Oviedo, Spain
| | - Christopher Dean
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
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Kupczyńska M, Czubaj N, Barszcz K, Sokołowski W, Czopowicz M, Purzyc H, Dzierzęcka M, Kinda W, Kiełbowicz Z. Prevalence of dorsal notch and variations in the foramen magnum shape in dogs of different breeds and morphotypes. Biologia (Bratisl) 2017. [DOI: 10.1515/biolog-2017-0018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Brachetta-Aporta N, Gonzalez PN, Bernal V. A quantitative approach for analysing bone modelling patterns from craniofacial surfaces in hominins. J Anat 2017; 232:3-14. [PMID: 29071711 DOI: 10.1111/joa.12716] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2017] [Indexed: 11/28/2022] Open
Abstract
Bone size and shape arise throughout ontogeny as a result of the coordinated activity of osteoblasts and osteoclasts, responsible for bone deposition and resorption, and growth displacements. The modelling processes leave specific microstructural features on the bone surface, which can be used to infer the mechanisms shaping craniofacial traits in extinct and extant species. However, the analysis of bone surfaces from fossils and archaeological samples faces some difficulties related to the bone loss caused by taphonomic factors, and the lack of formal methods for estimating missing information and comparing the patterns of bone modelling among several specimens and samples. The present study provides a new approach for the quantitative analysis of bone formation and resorption patterns obtained from craniofacial surfaces. First, interpolation techniques were used to estimate missing data on high-resolution replicas of the left maxilla in a sample of sub-adult and adult modern humans and sub-adult fossil hominins. The performance of this approach was assessed by simulating variable amounts of missing data. Then, we applied measures of dispersion and central tendency to represent the variation and average pattern of bone modelling within samples. The spatial interpolation resulted in reliable estimations of the type of cell activity (deposition or resorption) in the missing areas, even when large extensions of the bone surface were lost. The quantification of the histological data allowed us to integrate the information of different specimens and depict the areas with higher and lower variation in the bone modelling pattern of the maxilla among specimens. Overall, the main advantages of the quantitative approach used here for generating bone modelling patterns are the high replicability and the possibility of incorporating variation among specimens into the comparisons among samples.
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Affiliation(s)
- Natalia Brachetta-Aporta
- División Antropología, Facultad de Ciencias Naturales y Museo, CONICET, Universidad Nacional de La Plata, La Plata, Argentina
| | - Paula N Gonzalez
- CONICET, Unidad Ejecutora-Estudios en Neurociencias y Sistemas Complejos, Florencio Varela, Argentina
| | - Valeria Bernal
- División Antropología, Facultad de Ciencias Naturales y Museo, CONICET, Universidad Nacional de La Plata, La Plata, Argentina
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10
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Driver CJ, De Risio L, Hamilton S, Rusbridge C, Dennis R, McGonnell IM, Volk HA. Changes over time in craniocerebral morphology and syringomyelia in cavalier King Charles spaniels with Chiari-like malformation. BMC Vet Res 2012; 8:215. [PMID: 23136935 PMCID: PMC3514376 DOI: 10.1186/1746-6148-8-215] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 10/31/2012] [Indexed: 01/22/2023] Open
Abstract
Background Chiari-like malformation (CM) and syringomyelia is a neurological disease complex with high prevalence in cavalier King Charles spaniels (CKCS). The natural progression of this disease with time has not been described. The objectives of this study were to i) determine if syringomyelia progresses with time ii) determine if features of craniocrebral morphology previously associated with CM are progressive (including caudal cranial fossa volume, caudal cranial fossa parenchymal volume, ventricular dimensions, height of the foramen magnum and degree of cerebellar herniation). A retrospective morphometric analysis was undertaken in 12 CKCS with CM for which repeat magnetic resonance images were available without surgical intervention. Results The maximal syrinx width, height of the foramen magnum, length of cerebellar herniation and caudal cranial fossa volume increased over time. Ventricular and caudal fossa parenchymal volumes were not significantly different between scans. Conclusions The results of this study suggest that syringomyelia progresses with time. Increased caudal cranial fossa volume may be associated with active resorption of the supraoccipital bone, which has previously been found in histology specimens from adult CKCS. We hypothesise that active resorption of the supraoccipital bone occurs due to pressure from the cerebellum. These findings have important implications for our understanding of the pathogenesis and variable natural clinical progression of CM and syringomyelia in CKCS.
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Affiliation(s)
- Colin J Driver
- Department of Veterinary Clinical Sciences, Royal Veterinary College, London, UK.
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11
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Shaw TA, McGonnell IM, Driver CJ, Rusbridge C, Volk HA. Increase in cerebellar volume in Cavalier King Charles Spaniels with Chiari-like malformation and its role in the development of syringomyelia. PLoS One 2012; 7:e33660. [PMID: 22506005 PMCID: PMC3323625 DOI: 10.1371/journal.pone.0033660] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 02/19/2012] [Indexed: 12/14/2022] Open
Abstract
Previous research in Cavalier King Charles Spaniels (CKCS) has found that Chiari-like malformation and syringomyelia (CM/SM) are associated with a volume mismatch between the caudal cranial fossa (CCF) and the brain parenchyma contained within. The objectives of this study were to i) compare cerebellar volume in CKCS (a "high risk' group which frequently develops CM/SM), small breed dogs (medium risk--occasionally develop CM/SM), and Labradors (low risk--CM/SM not reported); ii) evaluate a possible association between increased cerebellar volume and CM/SM in CKCS; iii) investigate the relationship between increased cerebellar volume and crowding of the cerebellum in the caudal part of the CCF (i.e. the region of the foramen magnum). Volumes of three-dimensional, magnetic resonance imaging derived models of the CCF and cerebellum were obtained from 75 CKCS, 44 small breed dogs, and 31 Labradors. As SM is thought to be a late onset disease process, two subgroups were formed for comparison: 18 CKCS younger than 2 years with SM (CM/SM group) and 13 CKCS older than 5 years without SM (CM group). Relative cerebellar volume was defined as the volume of the cerebellum divided by the total volume of brain parenchyma. Our results show that the CKCS has a relatively larger cerebellum than small breed dogs and Labradors and provide evidence that increased cerebellar volume in CKCS is associated with crowding of cerebellum in the caudal part of the CCF. In CKCS there is an association between increased cerebellar volume and SM. These findings have implications for the understanding of the pathological mechanisms of CM/SM, and support the hypothesis that it is a multifactorial disease process governed by increased cerebellar volume and failure of the CCF to reach a commensurate size.
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Affiliation(s)
- Thomas A. Shaw
- Department of Veterinary Clinical Sciences, Royal Veterinary College, Hatfield, Hertfordshire, United Kingdom
| | - Imelda M. McGonnell
- Department of Veterinary Basic Sciences, The Royal Veterinary College, London, United Kingdom
| | - Colin J. Driver
- Department of Veterinary Clinical Sciences, Royal Veterinary College, Hatfield, Hertfordshire, United Kingdom
| | - Clare Rusbridge
- Stone Lion Veterinary Hospital, Wimbledon, London, United Kingdom
| | - Holger A. Volk
- Department of Veterinary Clinical Sciences, Royal Veterinary College, Hatfield, Hertfordshire, United Kingdom
- * E-mail:
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