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Orthopaedics
Published in Roy Palmer, Diana Wetherill, Medicine for Lawyers, 2020
Figure 13.1 shows the various parts of the bone, which may need further description. A long bone, such as the tibia (shin bone) or humerus (the upper arm bone), or short long bones, such as the metacarpals (the bones you see on the back of the hand) and metatarsals (in the feet) are divided up into several parts for descriptive purposes. At either end is an epiphysis. The periosteum is an outer membrane of bone-forming tissue and this assists with growth during the growing period and is also responsible for laying down bone during fracture healing throughout the patient’s life. Endosteum is a similar lining of tissue within the bone between the compact (or hard) outer bone and the spongy bone of the medullary cavity (the marrow of the bone). Where a bone takes part in a joint it is covered by what is known as articular cartilage. A bone derives its nutrition from the nutrient arteries that reach it either by perforating the hard outer bone (the cortex) or by way of the joint capsules, which are connected to the bone near the edges of the joint.
Swimming
Published in Paul Grimshaw, Michael Cole, Adrian Burden, Neil Fowler, Instant Notes in Sport and Exercise Biomechanics, 2019
During the pull phase, the shoulder is adducted and internally rotated and often the arm follows an inverted question mark pattern under the water. This allows the application of a force for a longer period of time, utilising the lift principle of propulsion. This action causes the head of the humerus (the upper arm bone) to move under the coracoacromial arch, which can lead to a potential impingement situation. One of the most common technical faults during this phase is the “dropped elbow”. The dropping of the elbow during the pull phase causes increased unwanted external shoulder rotation. However, the “high elbow” technique, which provides the muscles with a mechanical advantage, may also present an associated impingement risk. From initial “catch”, the hand sweeps down and slightly outwards while ideally maintaining a high elbow position to the deepest point of the stroke. Next, the hand sweeps inwards and upwards until an angle of approximately 90 degrees of the upper arm and forearm is reached. The in-sweep phase may take the hand past the mid-line of the body or under the outside edge of the body. From the mid-stroke position, the hand is first swept outwards and then backwards, finishing at the end of the pull past the hips as it exits the water. An increased acceleration of the hand towards the end of the pull and internal rotation and adduction of the shoulder may present a potential impingement problem (Figure F6.13 shows both the dropped and high elbow position during the modern front crawl swimming pull phase).
Strength and Speed/Power Athletes
Published in Henry C. Lukaski, Body Composition, 2017
David H. Fukuda, Jay R. Hoffman, Jeffrey R. Stout
With regard to muscle fiber type, experienced hammer throwers showed a greater percentage of type IIa fibers (51.1 ± 9.0% vs. 34.4 ± 6.0%), with comparable percentage of IIx fibers (9.0 ± 7.0% vs. 14.3 ± 7.0%), and a lesser percentage of type I fibers (39.9 ± 5.0% vs. 51.4 ± 7.0%) compared to untrained controls (Terzis et al. 2010). However, only the cross-sectional area of type IIa fibers (7703 ± 1171 μm2 vs. 5676 ± 1270 μm2) were found to be larger in the throwing athletes (Terzis et al. 2010). The hammer throwers also had significantly greater bone mineral density (1.484 ± 0.046 g/cm2 vs. 1.264 ± 0.080 g/cm2) than the control group (Terzis et al. 2010). Similar findings were reported in male collegiate shot putters with regard to total body and regional bone mineral densities (Whittington et al. 2009). Furthermore, male throwing athletes had greater bone mineral density than female throwing athletes, and regional bone mineral density values were significantly correlated with peak force (r > 0.79) and rate of force development (r = 0.89) generated during an isometric mid-thigh pull test as well as ball throw performance (r > 0.81) (Whittington et al. 2009). Interestingly, the combined group of shot put athletes showed bilateral differences in arm bone mineral density suggesting specific physiological adaptations to the athlete’s dominant or throwing side (Whittington et al. 2009).
A novel redox-responsive ursolic acid polymeric prodrug delivery system for osteosarcoma therapy
Published in Drug Delivery, 2021
Daijie Fu, Zhe Ni, Kerong Wu, Peng Cheng, Xiaofeng Ji, Guoyuan Li, Xifu Shang
Osteosarcoma (OS) accounts for nearly 60% of all bone cancers (Duan et al., 2017). OS usually develops in the upper arm bone, shinbone, and thighbone. OS is often accompanied by a high risk of metastasis and death (Wu et al., 2016). Although chemotherapy has made significant progress to increase the survival rate of patients with the localized OS, the treatment of advanced, metastatic, and relapsed OS is still less than satisfactory, and the five-year survival rate of OS with metastases is only 20% (Wang et al., 2015; Zhang et al., 2016a). Additionally, severe side effects, such as myelosuppression, gastrointestinal toxicity, and hypersensitivity, and resistance toward conventional chemotherapy have greatly reduced the quality of life of patients (Shen et al., 2016; Zhang et al., 2017, 2018). Thus, there is an urgent need to identify superior and more efficacious treatment strategies.
Return to physical activity six months after fracture – a prospective cohort study
Published in European Journal of Physiotherapy, 2021
Martin Johansson, Camilla Paludan Nielsen, Anders Falk Brekke, Marianne Lindahl
Beyond the importance for lifestyle-related diseases [1,3], Høidrup et al. [25] find in their large prospective population-based cohort study that even a level of light physical activity reduces the risk of hip fracture. They also found that a decrease in physical activity increased this risk. This finding supports that therapists should address that patients with fracture maintain a certain level of physical activity despite a period with immobilisation. Further, Kronhed et al. [26] report in their cross-sectional study that moderate leisure-time physical activity significantly relates to a higher fore-arm bone mass density (p = .042) and support the hypothesis that high level of physical activity plays a role in the prevention of osteoporosis.