The anatomical snuff box or snuffbox is a triangular deepening on the radial, dorsal aspect of the hand—at the level of the carpal bones the scaphoid and trapezium bones forming the floor. The name originates from the use of this surface for placing and sniffing powdered tobacco, or "snuff." It is sometimes referred to by its French name tabatière. The medial border of the snuffbox is the tendon of the extensor pollicis longus; the lateral border is a pair of parallel and intimate tendons, of the extensor pollicis brevis and the abductor pollicis longus. The proximal border is formed by the styloid process of the radius The distal border is formed by the approximate apex of the schematic snuffbox isosceles triangle; the floor of the snuffbox varies depending on the position of the wrist, but both the trapezium and the scaphoid can be palpated. Deep to the tendons which form the borders of the anatomical snuff box lies the radial artery, which passes through the anatomical snuffbox on its course from the normal radial pulse detecting area, to the proximal space in between the first and second metacarpals to contribute to the superficial and deep palmar arches.
In the anatomical snuffbox, the radial artery is related with the superficial branch of radial nerve near the styloid process of radius in 48%, while in 24% the radial artery is related to the lateral cutaneous nerve of forearm. The cephalic vein arises within the anatomical snuffbox, while the dorsal cutaneous branch of the radial nerve can be palpated by stroking along the extensor pollicis longus with the dorsal aspect of a fingernail; the radius and scaphoid articulate deep to the snuffbox to form the basis of the wrist joint. In the event of a fall onto an outstretched hand, this is the area through which the brunt of the force will focus; this results in these two bones being the most fractured of the wrist. In a case where there is localized tenderness within the snuffbox, knowledge of wrist anatomy leads to the speedy conclusion that the fracture is to be of the scaphoid; this is understandable as the scaphoid is a small, oddly shaped bone whose purpose is to facilitate mobility rather than confer stability to the wrist joint.
In the event of inordinate application of force over the wrist, this small scaphoid is to be the weak link. Scaphoid fracture is one of the most frequent causes of medico-legal issues. An anatomical anomaly in the vascular supply to the scaphoid is the area to which the blood supply is first delivered. Blood enters the scaphoid distally. In the event of a fracture the proximal segment of the scaphoid will be devoid of a vascular supply, will—if action is not taken—avascularly necrose within a sufferer's snuffbox. Due to the small size of the scaphoid and its shape, it is difficult to determine, early on, whether or not the scaphoid is indeed fractured with an x-ray. Further complications include. "Instant Anatomy"
A pianist is an individual musician who plays the piano. Since most forms of Western music can make use of the piano, pianists have a wide repertoire and a wide variety of styles to choose from, among them traditional classical music, jazz and all sorts of popular music, including rock and roll. Most pianists can, to an extent play other keyboard-related instruments such as the synthesizer, harpsichord and the organ. Modern classical pianists dedicate their careers to performing, teaching and learning new works to expand their repertoire, they do not write or transcribe music as pianists did in the 19th century. Some classical pianists might specialize in accompaniment and chamber music, while others will perform as full-time soloists. Mozart could be considered the first "concert pianist" as he performed on the piano. Composers Beethoven and Clementi from the classical era were famed for their playing, as were, from the romantic era, Brahms, Chopin and Rachmaninoff. From that era, leading performers less known as composers were Hans von Bülow.
However, as we do not have modern audio recordings of most of these pianists, we rely on written commentary to give us an account of their technique and style. Jazz pianists always perform with other musicians, their playing is more free than that of classical pianists and they create an air of spontaneity in their performances. They do not write down their compositions. Well known jazz pianists include Art Tatum, Duke Ellington, Thelonious Monk, Oscar Peterson and Bud Powell. Popular pianists might work as live performers, session musicians, arrangers most feel at home with synthesizers and other electronic keyboard instruments. Notable popular pianists include Victor Borge. A single listing of pianists in all genres would be impractical, given the multitude of musicians noted for their performances on the instrument. Below are links to lists of well-known or influential pianists divided by genres: List of classical pianists List of classical pianists List of classical piano duos List of jazz pianists List of pop and rock pianists List of blues musicians List of boogie woogie musicians List of gospel musicians List of new-age music artists Many important composers were virtuoso pianists.
The following is an incomplete list of such musicians. Franz Schubert Ludwig van Beethoven Wolfgang Amadeus Mozart Johann Nepomuk Hummel Carl Maria von Weber Muzio Clementi Edvard Grieg Franz Liszt Charles-Valentin Alkan Anton Arensky Sergei Rachmaninoff Anton Rubinstein Frédéric Chopin Felix Mendelssohn Johannes Brahms Camille Saint-Saëns Isaac Albéniz Nikolai Medtner Béla Bartók George Gershwin Sergei Prokofiev Dmitri Shostakovich Some people, having received a solid piano training in their youth, decide not to continue their musical careers but choose nonmusical ones; as a result, there are prominent communities of amateur pianists all over the world that play at quite a high level and give concerts not to earn money but just for the love of music. The International Piano Competition for Outstanding Amateurs, held annually in Paris, attracts about one thousand listeners each year and is broadcast on French radio, it is notable that Jon Nakamatsu, the Gold Medal winner of the Van Cliburn International Piano Competition for professional pianists in Fort Worth, Texas was at the moment of his victory technically an amateur: he never attended a music conservatory or majored in music, worked as a high school German teacher at the time.
The German pianist Davide Martello is known for traveling around conflict zones to play his moving piano. Martello has been recognised by the European parliament for his “outstanding contribution to European cooperation and the promotion of common values”. List of films about pianists
Interphalangeal joints of the hand
The interphalangeal joints of the hand are the hinge joints between the phalanges of the fingers that provide flexion towards the palm of the hand. There are two sets in each finger: "proximal interphalangeal joints", those between the first and second phalanges "distal interphalangeal joints", those between the second and third phalangesAnatomically, the proximal and distal interphalangeal joints are similar. There are some minor differences in how the palmar plates are attached proximally and in the segmentation of the flexor tendon sheath, but the major differences are the smaller dimension and reduced mobility of the distal joint; the PIP joint exhibits great lateral stability. Its transverse diameter is greater than its antero-posterior diameter and its thick collateral ligaments are tight in all positions during flexion, contrary to those in the metacarpophalangeal joint; the capsule, extensor tendon, skin are thin and lax dorsally, allowing for both phalanx bones to flex more than 100° until the base of the middle phalanx makes contact with the condylar notch of the proximal phalanx.
At the level of the PIP joint the extensor mechanism splits into three bands. The central slip attaches to the dorsal tubercle of the middle phalanx near the PIP joint; the pair of lateral bands, to which contribute the extensor tendons, continue past the PIP joint dorsally to the joint axis. These three bands are united by a transverse retinacular ligament, which runs from the palmar border of the lateral band to the flexor sheath at the level of the joint and which prevents dorsal displacement of that lateral band. On the palmar side of the joint axis of motion, lies the oblique retinacular ligament which stretches from the flexor sheath over the proximal phalanx to the terminal extensor tendon. In extension, the oblique ligament prevents passive DIP flexion and PIP hyperextension as it tightens and pulls the terminal extensor tendon proximally. In contrast, on the palmar side, a thick ligament prevents hyperextension; the distal part of the palmar ligament, called the palmar plate, is 2 to 3 millimetres thick and has a fibrocartilaginous structure.
The presence of chondroitin and keratan sulfate in the dorsal and palmar plates is important in resisting compression forces against the condyles of the proximal phalanx. Together these structures protect the tendons passing behind the joint; these tendons can sustain traction forces thanks to their collagen fibers. The palmar ligament is more flexible in its central-proximal part. On both sides it is reinforced by the so-called check rein ligaments; the accessory collateral ligaments originate at the proximal phalanx and are inserted distally at the base of the middle phalanx below the collateral ligaments. The accessory ligament and the proximal margin of the palmar plate are flexible and fold back upon themselves during flexion; the flexor tendon sheaths are attached to the proximal and middle phalanges by annular pulleys A2 and A4, while the A3 pulley and the proximal fibres of the C1 ligament attach the sheaths to the mobile volar ligament at the PIP joint. During flexion this arrangement produces a space at the neck of the proximal phalanx, filled by the folding palmar plate.
The palmar plate is supported by a ligament on either side of the joint called the collateral ligaments, which prevent deviation of the joint from side to side. The ligaments can or tear and can avulse with a small fracture fragment when the finger is forced backwards into hyperextension; this is called a "palmar plate, or volar plate injury". The palmar plate forms a semi-rigid floor and the collateral ligaments the walls in a mobile box which moves together with the distal part of the joint and provides stability to the joint during its entire range of motion; because the palmar plate adheres to the flexor digitorum superficialis near the distal attachment of the muscle, it increases the moment of flexor action. In the PIP joint, extension is more limited because of the two so called check-rein ligaments, which attach the palmar plate to the proximal phalanx; the only movements permitted in the interphalangeal joints are extension. Flexion is more extensive, about 100°, in the PIP joints and more restricted, about 80°, in the DIP joints.
Extension is limited by the collateral ligaments. The muscles generating these movements are: The relative length of the digit varies during motion of the IP joints; the length of the palmar aspect decreases during flexion while the dorsal aspect increases by about 24 mm. The useful range of motion of the PIP joint is 30–70°, increasing from the index finger to the little finger. During maximum flexion the base of the middle phalanx is pressed into the retrocondylar recess of the proximal phalanx, which provides maximum stability to the joint; the stability of the PIP joint is dependent of the tendons passing around it. Rheumatoid arthritis spares the distal interphalangeal joints. Therefore, arthritis of the distal interphalangeal joints suggests the presence of osteoarthritis or psoriatic arthritis. Interphalangeal joints of foot Hand kinesiology at the University of Kansas Medical Center Diagram at depuy.com Volar Plate Injury - Hand Therapy This article incorporates text in the public domain from page 333 of the 20th edition of Gray's Anatomy
Radial dysplasia known as radial club hand or radial longitudinal deficiency, is a congenital difference occurring in a longitudinal direction resulting in radial deviation of the wrist and shortening of the forearm. It can occur in different ways, from a minor anomaly to complete absence of the radius, radial side of the carpal bones and thumb. Hypoplasia of the distal humerus can lead to stiffness of the elbow. Radial deviation of the wrist is caused by lack of support to the carpus, radial deviation may be reinforced if forearm muscles are functioning poorly or have abnormal insertions. Although radial longitudinal deficiency is bilateral, the extent of involvement is most asymmetric; the incidence is between 1:30,000 and 1:100,000 and it is more a sporadic mutation rather than an inherited condition. In case of an inherited condition, several syndromes are known for an association with radial dysplasia, such as the cardiovascular Holt-Oram syndrome, the gastrointestinal VATER syndrome and the hematologic Fanconi anemia and TAR syndrome.
Other possible causes are an injury to the apical ectodermal ridge during upper limb development, intrauterine compression, or maternal drug use. Classification of radial dysplasia is practised through different models; some only include the different deformities or absences of the radius, where others include anomalies of the thumb and carpal bones. The Bayne and Klug classification discriminates four different types of radial dysplasia. A fifth type was added by Goldfarb et al. describing a radial dysplasia with participation of the humerus. In this classification only anomalies of the radius and the humerus are taken in consideration. James and colleagues expanded this classification by including deficiencies of the carpal bones with a normal distal radius length as type 0 and isolated thumb anomalies as type N. Type N: Isolated thumb anomaly Type 0: Deficiency of the carpal bones Type I: Short distal radius Type II: Hypoplastic radius in miniature Type III: Absent distal radius Type IV: Complete absent radius Type V: Complete absent radius and manifestations in the proximal humerus The term absent radius can refer to the last 3 types.
In cases of a minor deviation of the wrist, treatment by splinting and stretching alone may be a sufficient approach in treating the radial deviation in RD. Besides that, the parent can support this treatment by performing passive exercises of the hand; this will help to stretch the wrist and possibly correct any extension contracture of the elbow. Furthermore, splinting is used as a postoperative measure trying to avoid a relapse of the radial deviation. More severe types of radial dysplasia can be treated with surgical intervention; the main goal of centralization is to increase hand function by positioning the hand over the distal ulna, stabilizing the wrist in straight position. Splinting or soft-tissue distraction may be used preceding the centralization. In classic centralization central portions of the carpus are removed to create a notch for placement of the ulna. A different approach is to place the metacarpal of the middle finger in line with the ulna with a fixation pin. If radial tissues are still too short after soft-tissue stretching, soft tissue release and different approaches for manipulation of the forearm bones may be used to enable the placement of the hand onto the ulna.
Possible approaches are removing carpal bones. If the ulna is bent, osteotomy may be needed to straighten the ulna. After placing the wrist in the correct position, radial wrist extensors are transferred to the extensor carpi ulnaris tendon, to help stabilize the wrist in straight position. If the thumb or its carpometacarpal joint is absent, centralization can be followed by pollicization. Postoperatively, a long arm plaster splinter has to be worn for at least 6 to 8 weeks. A removable splint is worn for a long period of time. Radial angulation of the hand enables patients with stiff elbows to reach their mouth for feeding. A risk of centralization is that the procedure may cause injury to the ulnar physis, leading to early epiphyseal arrest of the ulna, thereby resulting in an shorter forearm. Sestero et al. reported that ulnar growth after centralization reaches from 48% to 58% of normal ulnar length, while ulnar growth in untreated patients reaches 64% of normal ulnar length. Several reviews note that centralization can only correct radial deviation of the wrist and that studies with longterm follow-up show relapse of radial deviation.
Buck-Gramcko described another operation technique, for treatment of radial dysplasia, called radialization. During radialization the metacarpal of the index finger is pinned onto the ulna and radial wrist extensors are attached to the ulnar side of the wrist, causing overcorrection or ulnar deviation; this overcorrection is believed to make relapse of radial deviation less likely. Villki reported a different approach in During this procedure a vascularised MTP-joint of the second toe is transferred to the radial side of ulna, creating a platform that provides radial support for the wrist; the graft is vascularised and therefore maintains its ability to join the growth of the supporting ulna. Prior to the actual transfer of the MTP-joint of the second toe soft-tissue distraction of the wrist is required to create enough space to place the MTP joint; when after several weeks enough space has been created through distraction, the actual transfer of the MTP joint can be initiated. During this surgical intervention the wrist and the second toe are prepared for transfer at the same time.
The ipsilateral second toe MT
A primate is a eutherian mammal constituting the taxonomic order Primates. Primates arose 85–55 million years ago from small terrestrial mammals, which adapted to living in the trees of tropical forests: many primate characteristics represent adaptations to life in this challenging environment, including large brains, visual acuity, color vision, altered shoulder girdle, dexterous hands. Primates range in size from Madame Berthe's mouse lemur, which weighs 30 g, to the eastern gorilla, weighing over 200 kg. There are 190 -- 448 species of living primates, depending on. New primate species continue to be discovered: over 25 species were described in the first decade of the 2000s, eleven since 2010. Primates are divided into two distinct suborders; the first is the strepsirrhines - lemurs and lorisids. The second is haplorhines - the "dry-nosed" primates - tarsier and ape clades, the last of these including humans. Simians are monkeys and apes, cladistically including: the catarrhines consisting of the Old World monkeys and apes.
Forty million years ago, simians from Africa migrated to South America by drifting on debris, gave rise to the New World monkeys. Twenty five million years ago the remaining Old World simians split into Old World monkeys. Common names for the simians are the baboons, macaques and great apes. Primates have large brains compared to other mammals, as well as an increased reliance on visual acuity at the expense of the sense of smell, the dominant sensory system in most mammals; these features are more developed in monkeys and apes, noticeably less so in lorises and lemurs. Some primates are trichromats, with three independent channels for conveying color information. Except for apes, primates have tails. Most primates have opposable thumbs. Many species are sexually dimorphic. Primates have slower rates of development than other sized mammals, reach maturity and have longer lifespans. Depending on the species, adults may live in solitude, in mated pairs, or in groups of up to hundreds of members; some primates, including gorillas and baboons, are terrestrial rather than arboreal, but all species have adaptations for climbing trees.
Arboreal locomotion techniques used include leaping from tree to tree and swinging between branches of trees. Primates are among the most social of animals, forming pairs or family groups, uni-male harems, multi-male/multi-female groups. Non-human primates have at four types of social systems, many defined by the amount of movement by adolescent females between groups. Most primate species remain at least arboreal: the exceptions are some great apes and humans, who left the trees for the ground and now inhabit every continent. Close interactions between humans and non-human primates can create opportunities for the transmission of zoonotic diseases virus diseases, including herpes, ebola and hepatitis. Thousands of non-human primates are used in research around the world because of their psychological and physiological similarity to humans. About 60% of primate species are threatened with extinction. Common threats include deforestation, forest fragmentation, monkey drives, primate hunting for use in medicines, as pets, for food.
Large-scale tropical forest clearing for agriculture most threatens primates. The English name "primates" is derived from Old French or French primat, from a noun use of Latin primat-, from primus; the name was given by Carl Linnaeus. The relationships among the different groups of primates were not understood until recently, so the used terms are somewhat confused. For example, "ape" has been used either as an alternative for "monkey" or for any tailless human-like primate. Sir Wilfrid Le Gros Clark was one of the primatologists who developed the idea of trends in primate evolution and the methodology of arranging the living members of an order into an "ascending series" leading to humans. Used names for groups of primates such as "prosimians", "monkeys", "lesser apes", "great apes" reflect this methodology. According to our current understanding of the evolutionary history of the primates, several of these groups are paraphyletic: a paraphyletic group is one which does not include all the descendants of the group's common ancestor.
In contrast with Clark's methodology, modern classifications identify only those groupings that are monophyletic. The cladogram below shows one possible classification sequence of the living primates: groups that use common names are shown on the right. All groups with scientific names are monophyletic, the sequence of scientific classification reflects the evolution
A joint or articulation is the connection made between bones in the body which link the skeletal system into a functional whole. They are constructed to allow for different types of movement; some joints, such as the knee and shoulder, are self-lubricating frictionless, are able to withstand compression and maintain heavy loads while still executing smooth and precise movements. Other joints such as sutures between the bones of the skull permit little movement in order to protect the brain and the sense organs; the connection between a tooth and the jawbone is called a joint, is described as a fibrous joint known as a gomphosis. Joints are classified both functionally. Joints are classified structurally and functionally. Structural classification is determined by how the bones connect to each other, while functional classification is determined by the degree of movement between the articulating bones. In practice, there is significant overlap between the two types of classifications. Monoarticular – concerning one joint oligoarticular or pauciarticular – concerning 2–4 joints polyarticular – concerning 5 or more joints Structural classification names and divides joints according to the type of binding tissue that connects the bones to each other.
There are four structural classifications of joints: fibrous joint – joined by dense regular connective tissue, rich in collagen fibers cartilaginous joint – joined by cartilage. There are two types: primary cartilaginous joints composed of hyaline cartilage, secondary cartilaginous joints composed of hyaline cartilage covering the articular surfaces of the involved bones with fibrocartilage connecting them. Synovial joint – not directly joined – the bones have a synovial cavity and are united by the dense irregular connective tissue that forms the articular capsule, associated with accessory ligaments. Facet joint – joint between two articular processes between two vertebrae. Joints can be classified functionally according to the type and degree of movement they allow: Joint movements are described with reference to the basic anatomical planes. Synarthrosis – permits little or no mobility. Most synarthrosis joints are fibrous joints. Amphiarthrosis – permits slight mobility. Most amphiarthrosis joints are cartilaginous joints.
Synovial joint – movable. Synovial joints can in turn be classified into six groups according to the type of movement they allow: plane joint and socket joint, hinge joint, pivot joint, condyloid joint and saddle joint. Joints can be classified, according to the number of axes of movement they allow, into nonaxial, monoaxial and multiaxial. Another classification is according to the degrees of freedom allowed, distinguished between joints with one, two or three degrees of freedom. A further classification is according to the number and shapes of the articular surfaces: flat and convex surfaces. Types of articular surfaces include trochlear surfaces. Joints can be classified based on their anatomy or on their biomechanical properties. According to the anatomic classification, joints are subdivided into simple and compound, depending on the number of bones involved, into complex and combination joints: Simple joint: two articulation surfaces Compound joint: three or more articulation surfaces Complex joint: two or more articulation surfaces and an articular disc or meniscus The joints may be classified anatomically into the following groups: Joints of hand Elbow joints Wrist joints Axillary articulations Sternoclavicular joints Vertebral articulations Temporomandibular joints Sacroiliac joints Hip joints Knee joints Articulations of footUnmyelinated nerve fibers are abundant in joint capsules and ligaments as well as in the outer part of intraarticular menisci.
These nerve fibers are responsible for pain perception. Damaging the cartilage of joints or the bones and muscles that stabilize the joints can lead to joint dislocations and osteoarthritis. Swimming is a great way to exercise the joints with minimal damage. A joint disorder is termed arthropathy, when involving inflammation of one or more joints the disorder is called arthritis. Most joint disorders involve arthritis, but joint damage by external physical trauma is not termed arthritis. Arthropathies are called polyarticular when involving many joints and monoarticular when involving only a single joint. Arthritis is the leading cause of disability in people over the age of 55. There are many different forms of arthritis; the most common form of arthritis, occurs following trauma to the joint, following an infection of the joint or as a result of aging and the deterioration of articular cartilage. Furthermore, there is emerging evidence that abnormal anatomy may contribute to early development of osteoarthritis.
Other forms of arthritis are rheumatoid arthritis and psoriatic arthritis, which are autoimmune diseases in which the body is attacking itself. Septic arthritis is caused by joint infection. Gouty arthritis is caused by deposition of uric acid crystals in the joint that results in subsequent inflammation. Additionally, there is a less common form of gout, caused by the formation of rhomboidal-shaped crystals of calcium pyrophosphate; this form of gout is known as pseudogout. Temporomandibular joint syndrome involves the jaw joints and can cause facial p
Lumbricals of the hand
The lumbricals are intrinsic muscles of the hand that flex the metacarpophalangeal joints and extend the interphalangeal joints. The lumbrical muscles of the foot have a similar action, though they are of less clinical concern; the lumbricals are four, worm-like muscles on each hand. These muscles are unusual in. Instead, they attach proximally to the tendons of flexor digitorum profundus and distally to the extensor expansions; the first and second lumbricals are innervated by the median nerve. The third and fourth lumbricals are innervated by the ulnar nerve; this is the usual innervation of the lumbricals. However 1:3 and 3:1 exist; the lumbrical innervation always follows the innervation pattern of the associated muscle unit of flexor digitorum profundus. Four separate sources supply blood to these muscles: the superficial palmar arch, the common palmar digital artery, the deep palmar arch, the dorsal digital artery; the lumbrical muscles, with the help of the interosseous muscles flex the metacarpophalangeal joints while extending both interphalangeal joints of the digit on which it inserts.
The lumbricals are used during an upstroke in writing