China
Africa
Explore chapters and articles related to this topic
Osteoporosis
Published in Jason Liebowitz, Philip Seo, David Hellmann, Michael Zeide, Clinical Innovation in Rheumatology, 2023
Mazen Nasrallah, Marcy B. Bolster
Osteoporosis is a common disease characterized by loss of bone mass, disruption of normal bone architecture, increased skeletal fragility, reduced bone strength, and an increased risk of fracture. Osteoporosis is defined by the World Health Organization (WHO) as a bone density that falls 2.5 standard deviations (SD) below the mean for young healthy adults of the same sex and race—also referred to as a T-score of –2.5. The diagnosis can also be made in patients who have sustained a fragility fracture, even in the absence of osteoporosis by bone densitometry. The disease is most prevalent among postmenopausal women; however, it can affect women and men as a function of age and with underlying conditions that predispose to bone mass loss. Osteoporosis has no clinical manifestations until it results in a fracture, which most commonly affects the vertebral spine (two-thirds of which are asymptomatic). Other fractures can occur, most feared of which are hip fractures, which are associated with significant morbidity and mortality.
Bio-Implants Derived from Biocompatible and Biodegradable Biopolymeric Materials
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
Joints in any parts of the body are important components of the skeletal system. It is positioned at bone joints for the transmission of loads from bone to bone by muscular action; also, there can be some relative motion of the component bones. Tissue of a bone is complex in nature and the composite consisting of soft and strong protein collagen and brittle hydroxyapatite. Bone is an anisotropic material with mechanical properties that differ in the longitudinal (axial) and transverse (radial) directions. The cartilage is a coating on each connecting surface, which consists of body fluids that lubricate and provide an interface with a very low coefficient of friction that provides the bone sliding movement. The human hip joint occurs at the junction between the pelvis and the upper leg (thigh) bone, or femur. Large rotary motion is allowable at the hip by a ball-and-socket type of joint. The top of the femur terminates in a ball-shaped head that fits into a cuplike cavity within the pelvis.
The Musculoskeletal System and Its Disorders
Published in Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss, Understanding Medical Terms, 2020
Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss
The musculoskeletal system serves as the basic framework arid motor system of the body and consists of the muscles, tendons, ligaments, joints, and bones of the skeleton. All of these components are interconnected and work together to support the body and to allow movement.
Long-term effects of mTBIs includes a higher dependency on visual inputs to control vertical posture
Published in Brain Injury, 2023
Alessander Danna-Dos-Santos, Patricia Driusso, Adriana Menezes Degani
Disproportionate deterioration of body postural control in medial-lateral direction has been described in postural studies conducted in other populations (48,49). However, its driving mechanisms remain unclear. We speculate this effect may be driven by a combination of anatomical aspects of the axial skeleton and the segmental distribution of its postural muscles. Specifically, the presence of two lower limbs positioned side-by-side and the reduced range-of motion of the knee joints in the frontal plane allow for relatively better medial-lateral stability. The parallel positioning of the two lower limbs increases the size of our base of support in the medial-lateral direction while allowing an effective transmission of reactive forces to partially counter-act the tendency of the body to lean on its side. As a result of this mechanical stability, the number of muscles dedicated to control medial-lateral balance can be reduced, therefore, making the muscular system dedicated to this type of control less redundant. Even though this less redundant system functions well in health, it might reduce the ability of the CNS to adapt its neuromechanisms of control when the controller itself is compromised by pathologies. Instability will then follow.
Static magnetic field-enhanced osteogenic differentiation of human umbilical cord-derived mesenchymal stem cells via matrix vesicle secretion
Published in International Journal of Radiation Biology, 2020
Ching-Yi Chang, Wei-Zhen Lew, Sheng-Wei Feng, Chung-Lung Wu, Hsin-Hui Wang, Sung-Chih Hsieh, Haw-Ming Huang
A skeleton is a unique structure that plays roles in load-bearing, movement, organ protection, and regulation of endocrine homeostasis (Walmsley et al. 2016). It undergoes self-regeneration instead of healing with a scar when the nature and extent of an injury are not large, chronic, severe, and complicated (Oryan et al. 2017). However, spontaneous regeneration may not occur when the injury extends beyond a critical size, leading to nonunion or formation of scar tissue (Walmsley et al. 2016). Upon a bony injury, the mesenchymal stem cells (MSCs) initiate the reparative process of bone regeneration, with the formation of soft and hard calluses (Oryan et al. 2017). Recruited MSCs differentiate to become either chondrocytes or osteoblasts and subsequently perform endochondral ossification or intramembranous ossification, respectively (Knight and Hankenson 2013). Several attempts have been made to manipulate and enhance the osteogenic capabilities of endogenous MSCs (Knight and Hankenson 2013). However, in many cases of disease or severe injury, these endogenous stem cell populations are insufficient to cure those situations due to the low quantity and potency. With the advent of modern strategies of tissue engineering and regenerative medicine, tissue scaffolds, healing promotive factors, and mesenchymal stem cells have been used to improve bone repair and regeneration (Oryan et al. 2017). Research has focused on nontissue-specific stem cell sources for direct application to increase osteogenesis in bone repair.
Bone mineral density and serum osteocalcin levels in patients with gout
Published in Acta Clinica Belgica, 2019
Atalay Dogru, Ayse Balkarli, Cemile Canan Karatay, Veli Cobankara, Mehmet Sahin
Osteoporosis is a skeletal disorder leading to bone fragility and an increased risk of fractures. Throughout human life, new bones are formed by osteoblasts and old bones are periodically resorbed by osteoclasts. This process is termed ‘remodeling’ [4]. However, excessive resorption by osteoclasts without the corresponding amount of newly formed bone by osteoblasts results in osteoporosis [5,6]. Localized and generalized osteoporosis and related fragility fractures are commonly seen in rheumatoid arthritis (RA). Moreover, osteoporosis can be found at an increased rate in other rheumatological diseases including systemic lupus erythematosus, ankylosing spondylitis, spondyloarthropathy, and polymyalgia rheumatica. The reason for this increased rate of osteoporosis in patients with rheumatological diseases is multifactorial; it is considered to be associated with several factors including the underlying inflammatory process, decreased mobility, and, in particular, the use of corticosteroids. Accordingly, long-term glucocorticoid therapy cannot be considered as the only cause of the osteoporosis in patients with rheumatological diseases; rather, the rheumatological disease itself and inflammation, which can increase bone turnover, impair and weaken bone microarchitecture, and increase the risk of fractures, can also lead to the development of osteoporosis [7,8].