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Wolff's Law
Wolff's law, developed by the German anatomist and surgeon Julius Wolff (surgeon), Julius Wolff (1836–1902) in the 19th century, states that bone in a healthy animal will adapt to the loads under which it is placed. If loading on a particular bone increases, the bone will remodel itself over time to become stronger to resist that sort of loading. The internal architecture of the trabeculae undergoes adaptive changes, followed by secondary changes to the external cortical portion of the bone, perhaps becoming thicker as a result. The inverse is true as well: if the loading on a bone decreases, the bone will become less dense and weaker due to the lack of the stimulus required for continued bone remodeling, remodeling.Wolff J. "The Law of Bone Remodeling". Berlin Heidelberg New York: Springer, 1986 (translation of the German 1892 edition) This reduction in bone density (osteopenia) is known as stress shielding and can occur as a result of a hip replacement (or other prosthesis). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Julius Wolff (surgeon)
Julius Wolff (21 March 1836 – 18 February 1902) was a German surgeon. Biography Julius Wolf was born on 21 March 1836 in Mirosławiec, Märkisch Friedland, and received his doctorate in 1861 in the field of surgery under Bernhard von Langenbeck (1810–1887) at Humboldt University of Berlin, Friedrich-Wilhelms University in Berlin. In 1861 he settled down after the state examination as a general practitioner in Berlin. He participated as a surgeon in three military campaigns (1864, 1866, 1870/71). Based on observations in his long career as a surgeon, he postulated Wolff's law (original title 1892: The law of transformation of the bone), which describes the relationship between bone geometry and mechanical influences on bone. For this he was with leading scientists of his time in active contact. Karl Culmann (1821–1881), Wilhelm Roux (1850–1924), Christian Otto Mohr (1835–1918) and Albert Hoffa (1859–1907) gave him support for the interpretation and evaluation of its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteogenic Loading
Osteogenic loading (OL) is a rehabilitative exercise method with the goal of improving bone density and preventing bone fracture. This may be seen as brief, intensive, resistance exercise for bone health. Osteogenic loading is an outpatient therapy that typically is used with ambulatory individuals who are able to engage in resistance exercise. Loading exercise for bone density preservation and improvement is supported by bone health societies and organizations, including the International Osteoporosis Foundation, the National Osteoporosis Foundation, the National Osteoporosis Society of the United Kingdom, and the World Health Organization. The basis of osteogenic loading stems from Wolff's law Wolff's law, developed by the German anatomist and surgeon Julius Wolff (surgeon), Julius Wolff (1836–1902) in the 19th century, states that bone in a healthy animal will adapt to the loads under which it is placed. If loading on a particular ..., which shows that the force or loa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Matrix Hypothesis
In the development of vertebrate animals, the functional matrix hypothesis is a phenomenological description of bone growth. It proposes that "the origin, development and maintenance of all skeletal units are secondary, compensatory and mechanically obligatory responses to temporally and operationally prior demands of related functional matrices." The fundamental basis for this hypothesis, laid out by Columbia anatomy professor Melvin Moss is that bones do not ''grow'' but ''are grown'', thus stressing the ontogenetic primacy of function over form. This is in contrast to the current conventional scientific wisdom that genetic, rather than epigenetic (non-genetic) factors, control such growth. The theory was introduced as a chapter in a dental textbook in 1962.''New York Times'Dr. Melvin Moss, 83, Theorist on How Bones of Face Grow, Is Dead June 29, 2006 See also * Wolff's law Wolff's law, developed by the German anatomist and surgeon Julius Wolff (surgeon), Julius Wolff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torticollis
Torticollis, also known as wry neck, is an extremely painful, dystonic condition defined by an abnormal, asymmetrical head or neck position, which may be due to a variety of causes. The term ''torticollis'' is derived . The most common case has no obvious cause, and the pain and difficulty in turning the head usually goes away after a few days, even without treatment in adults. Signs and symptoms Torticollis is a fixed or dynamic tilt, rotation, with flexion or extension of the head and/or neck. The type of torticollis can be described depending on the positions of the head and neck. * laterocollis: the head is tipped toward the shoulder * rotational torticollis: the head rotates along the longitudinal axis towards the shoulder * anterocollis: forward flexion of the head and neck and brings the chin towards the chest * retrocollis: hyperextension of head and neck backward bringing the back of the head towards the back A combination of these movements may often be observed. To ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Density
Bone density, or bone mineral density, is the amount of bone mineral in bone tissue. The concept is of mass of mineral per volume of bone (relating to density in the physics sense), although medicine#Clinical practice, clinically it is measured by proxy according to optical density per square centimetre of bone surface upon medical imaging, imaging. Bone density measurement is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk. It is measured by a procedure called densitometry, often performed in the radiology or nuclear medicine departments of hospitals or clinics. The measurement is painless and non-invasive and involves low radiation exposure. Measurements are most commonly made over the lumbar spine and over the upper part of the hip. The forearm may be scanned if the hip and lumbar spine are not accessible. There is a statistics, statistical association between poor bone density and higher probability of fracture. Fractures of the legs and pel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weightlifter
Weightlifting or weight lifting generally refers to physical exercises and sports in which people lift weights, often in the form of dumbbells, barbells or machines. People engage in weightlifting for a variety of different reasons. These can include: developing physical strength; promoting health and fitness; competing in weightlifting sports; and developing a muscular and aesthetic physique. Olympic weightlifting is a specific type of weightlifting sport practiced at the Olympic Games, commonly referred to simply as "weightlifting". Other weightlifting sports include stone lifting, powerlifting, kettlebell lifting, and para powerlifting—the weightlifting sport practiced at the Paralympic Games. Different weightlifting sports may be distinguished by the different ways of lifting a weight, and/or the objects lifted. Weightlifting events are key elements of strength athletics. Weight training is weightlifting to develop physical strength and/or a muscular physique. It i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tennis
Tennis is a List of racket sports, racket sport that is played either individually against a single opponent (singles (tennis), singles) or between two teams of two players each (doubles (tennis), doubles). Each player uses a tennis racket strung with a cord to strike a hollow rubber tennis ball, ball covered with felt over or around a net and into the opponent's tennis court, court. The object is to manoeuvre the ball in such a way that the opponent is not able to play a valid return. If a player is unable to return the ball successfully, the opponent scores a Point (tennis), point. Playable at all levels of society and at all ages, tennis can be played by anyone who can hold a racket, including Wheelchair tennis, wheelchair users. The original forms of tennis developed in France during the late Middle Ages. The modern form of tennis originated in Birmingham, England, in the late 19th century as lawn tennis. It had close connections to various field (lawn) games such as croqu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racquet
A racket or racquet is an item of sporting equipment used to strike a ball or shuttlecock in a variety of sports. A racket consists of three major components: a widened distal end known as the ''head'', an elongated handle known as the ''grip'', and a reinforced connection between the head and handle known as the ''throat'' or ''heart''. The head of the racket forms a flattened firm surface, known as the ''face'', which is used to strike the ball or shuttlecock. In the strictest sense, the word "racket" specifically refers to a striking implement with a mesh face made of interlaced, tightly stretched string (structure), strings fixed on an ovoid frame known as the ''rim''. This type of racket is used in sports such as tennis, badminton, and racquetball. Some rackets have a rigid one-piece head with a solid or fenestrated face instead of a meshwork of strings. Such rackets are called a paddle or bat, and are used in sports such as table tennis, pickleball and padel. Collectively ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harold Frost
Harold M. Frost (1921 – 19 June 2004) was an American orthopedist and surgeon considered to be one of the most important researchers and theorists in the field of bone biology and bone medicine of his time.Turner C, Burr D, Jee WS, Smith S, Recker RR, Axelrod DW, Takahashi HE, Villanueva AR, High WB, Martin RB, Parfitt AM: ''Tribute to Harold M. Frost M.D.'', ''J Musculoskel Neuron Interact'' 2004; 4(4):348-356, Jee WS: ''Harold M. Frost, M.D., D.Sc. (hon) - one man's association'', ''J Musculoskelet Neuronal Interact.'' 2006 Apr-Jun;6(2):113-21, He published nearly 500 peer-reviewed scientific and clinical articles and 16 books. According to the Science Citation Index, he is one of the most cited investigators in skeletal research. Life He received his medical degree from Geisel School of Medicine and Feinberg School of Medicine in 1945. He then did his surgical internship in Worcester, Massachusetts. During this time, he served as an officer in the Naval Medical Corps fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
