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Human Diversity
Published in Stephen Pheasant, Christine M. Haslegrave, Bodyspace, 2018
Stephen Pheasant, Christine M. Haslegrave
The age at which we reach ‘anthropometric adulthood’ is by no means as clearcut as one might suppose. Growth standards conventionally stop at 16 years for girls and 18 years for boys. The growth of a long bone occurs by cell division in plates of cartilage which separate the ends (epiphyses) from the shaft (diaphysis). When this cartilage finally turns into bone, growth ceases (eiphyseal fusion). The clavicles continue to grow well into the twenties and so, to a lesser extent, do the bones of the spine. Andersson et al. (1965) demonstrated an increase in sitting height in a majority of boys after 18 years and girls after 17 years, as well as in some boys after 20 years. A sample of Americans studied by Roche and Davila (1972) reached their adult stature at a median age of 21.2 years for boys and 17.3 years for girls, but some 10% of boys grew after 23.5 years and 10% of girls after 21.1 years. According to Roche and Davila (1972), this was partially due to late epiphyseal fusion in the lower limbs and partially to lengthening of the spine. Miall et al. (1967), in a longitudinal study of two Welsh communities, found evidence that men might grow slightly in stature well into their thirties.
Mechanical testing
Published in C M Langton, C F Njeh, The Physical Measurement of Bone, 2016
Christopher F Njeh, Patrick H Nicholson, Jae-Young Rho
Whole bone, i.e. bone as an organ, consists not only of calcified bone matrix and bone cells but also of non-osseous cells, blood vessels, nerve fibres and bone marrow. Depending on the skeletal sites, bones may appear long tubular segments (long bones), bilaminar plates (flat bones) or short irregular prismatic structures (short bones). In long bones, three different regions can be distinguished (figure 5.1): the diaphysis (central shaft) which represents the longest part; the epiphysis, which are present at the two extremities; and the metaphysis, which lie between. A cartilaginous layer, the so-called growth plate, separates the metaphysis from the epiphysis in the growing skeleton, but tends to ossify as the skeleton matures. The long bones are present in the peripheral or appendicular skeleton, i.e. limbs, ribs and clavicles; the flat bones are typically found in the skull, scapula and pelvis and the short bones in the axial skeleton (vertebrae, sternum), carpus and tarsus. Independently of their macroscopic anatomy, all skeletal segments consists of an outer layer of compact bone and an inner zone (the medulla) which contains bone marrow (figure 5.1).
Techniques and Applications of Adaptive Bone Remodeling Concepts
Published in Cornelius Leondes, Musculoskeletal Models and Techniques, 2001
Nicole M. Grosland, Vijay K. Goel, Roderic S. Lakes
The sizes, shapes, and structures of human skeletal bones are quite well known. Each bone possesses a characteristic pattern of ossification and growth, a characteristic shape, and features that indicate its functional relationship to other bones, muscles, and to the body structure as a whole. The shape and surface features of each bone are related to its functional role in the skeleton. Long bones, for example, function as levers during body movement. Bones that support the body are massive, with large articulating surfaces and processes for muscular attachment. Because the primary responsibility of the skeleton is structural, bone has acquired the unfortunate reputation of being a simple material.14
The analogies between human development and additive manufacture: Expanding the definition of design
Published in Cogent Engineering, 2019
L. E. J. Thomas-Seale, J. C. Kirkman-Brown, S. Kanagalingam, M. M. Attallah, D. M. Espino, D. E. T. Shepherd
Intramembranous ossification which forms the skull bones is initiated by the proliferation of neural crest-derived mesenchymal cells; some form vessels and some differentiate into osteoblasts (Gilbert, 2003). The osteoblasts secrete an unmineralised osteoid matrix, into which calcium is deposited to form the calcified matrix, in which the osteocytes, become embedded (Moore et al., 2013a). Conversely, endochondral ossification, which forms the long bones, demonstrates an intermediate step where tissue is transformed from cartilage to bone. The mesenchymal cells, condense into nodules and differentiate into chondrocytes which secrete the molecules required for the extracellular matrix of cartilage (Schoenwolf et al., 2015). The subsequent hypertrophy of the chondrocytes has two key functions, firstly they secrete vesicles into the extracellular matrix, the enzymes of which initiate the mineralisation process (Gilbert, 2003) and secondly they lengthen the bone (Preston & Wilson, 2013).
Long bone fractures: treatment patterns and factors contributing to use of intramedullary nailing
Published in Expert Review of Medical Devices, 2020
Abhishek Chitnis, Bidusee Ray, Charisse Sparks, Yuriy Grebenyuk, Mollie Vanderkarr, Chantal E Holy
Long bones, including the femur, tibia, and humerus, are the most commonly fractured bones in the human body [1]. A broken hip or femur is one of the most serious fall injuries and is associated with disability and premature death [2]. Each year over 300,000 older people are hospitalized for femur fractures in the US [3]. Tibia fractures are common but unanticipated trauma results in painful and prolonged recovery, often associated with complications [1,4]. Tibia and fibula fractures annually result in 77,000 hospitalizations [4]. The incidence of humeral fractures has been increasing with the aging population resulting in a large socioeconomical burden [5].
The opportunity of using alloplastic bone augmentation materials in the maxillofacial region– Literature review
Published in Particulate Science and Technology, 2019
Simion Bran, Grigore Baciut, Mihaela Baciut, Ileana Mitre, Florin Onisor, Mihaela Hedesiu, Avram Manea
Considering the shape of the bones, four general categories can be described: long, short, flat and irregular bones. (Figure 3) Long bones include the clavicles, humeri, radii etc. Short bones include the carpal and tarsal bones, patellae etc. Flat bones include the skull, mandible, scapulae etc. Irregular bones include the vertebrae, sacrum, hyoid bone, maxilla etc. Flat bones form by membranous bone formation, and long bones are formed by a combination of endochondral and membranous bone formation (Clarke 2008).