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Wolff's Law
Wolff's law, developed by the German anatomist and 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 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). The normal stress on a bone is shielded ... [...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 Märkisch Friedland, and received his doctorate in 1861 in the field of surgery under Bernhard von Langenbeck (1810–1887) at 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 research. His work established the mech ... [...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 (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 bon ..., which shows that the force or loa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Shirt
Iron Shirt (; Cantonese: tit1 saam3) is a form of hard style martial art exercise believed to help protect the human body from impacts in a fight. This is one of the 72 arts of the Shaolin Temple. Some martial arts are based on the belief that a correctly trained body can withstand more damage than one that is untrained. Iron Shirt is said to be a series of exercises using many post stances, herbs, qigong and body movements to cause the body's natural energy ( qi) to reinforce its structural strength. Practitioners believe that directing energy to parts of the body can reinforce these parts of the body to take blows against them. In the Shaolin version of Iron Shirt, the practitioner would do things such as lying on a stump or supporting tablets of granite on the chest with the goal of toughening the body. Famous practitioners According to 13th generation lineage ''Tai He'' ("Great Harmony") Wudangquan Master ''Fan Ke Ping'' (), a collector of rare Kung fu manuals, Zhou Tong, ... [...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 (1836–1902) in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torticollis
Torticollis, also known as wry neck, is a 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 from the Latin words ''tortus, meaning "twisted"'' and ''collum, meaning "neck."'' The most common case has no obvious cause, and the pain and difficulty with 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 * anterocollis: forward flexion of the head and neck * retrocollis: hyperextension of head and neck backward A combination of these movements may often be observed. Torticollis can be a disorder in itself as wel ... [...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 clinically it is measured by proxy according to optical density per square centimetre of bone surface upon 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 statistical association between poor bone density and higher probability of fracture. Fractures of the legs and pelvis due to falls are a significant public health p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weightlifter
Olympic weightlifting, or Olympic-style weightlifting (officially named Weightlifting), is a sport in which athletes compete in lifting a barbell loaded with weight plates from the ground to overhead, with each athlete trying to successfully lift the heaviest weights. Athletes compete in two specific ways of lifting the barbell overhead: these are the snatch and the clean and jerk. The ''snatch'' is a wide-grip lift, in which the weighted barbell is lifted overhead in one motion. The ''clean and jerk'' is a combination lift, in which the weight is first taken from the ground to the front of the shoulders (the clean), and then from the shoulders to overhead (the jerk). The clean and press, wherein a clean was followed by an overhead press, was formerly also a competition lift, but was discontinued due to difficulties in judging proper form. Each weightlifter gets three attempts at both the snatch and the clean and jerk, with the snatch attempts being done first. An athlete's scor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tennis
Tennis is a racket sport that is played either individually against a single opponent ( singles) or between two teams of two players each ( doubles). Each player uses a tennis racket that is strung with cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent's court. The object of the game is to manoeuvre the ball in such a way that the opponent is not able to play a valid return. The player who is unable to return the ball validly will not gain a point, while the opposite player will. Tennis is an Olympic sport and is played at all levels of society and at all ages. The sport can be played by anyone who can hold a racket, including wheelchair users. The modern game of tennis originated in Birmingham, England, in the late 19th century as lawn tennis. It had close connections both to various field (lawn) games such as croquet and bowls as well as to the older racket sport today called real tennis. The rules of modern tennis have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racquet
A racket, or racquet, is a sports implement used for striking a ball or shuttlecock in games such as squash, tennis, racquetball, badminton and padel. In the strictest sense a racket consists of a handled frame with an open hoop across which a network of strings is stretched tightly. Some rackets may have a solid or perforated hitting surface instead of a network of strings. Such rackets may be called a paddle or bat. Collectively, these games are known as racket sports. Racket design, materials and manufacturing has changed considerably over the centuries. The frame of rackets for all sports was traditionally made of solid wood (later laminated wood) and the strings of animal intestine known as catgut. The traditional racket size was limited by the strength and weight of the wooden frame which had to be strong enough to hold the strings and stiff enough to hit the ball or shuttle. Manufacturers started adding non-wood laminates to wood rackets to improve stiffness. Non-wood ... [...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 was Officer in the Naval Medical Corps from 1946 to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
