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Ulnar Side (ulnar + side)

Distribution by Scientific Domains

Life Sciences	100%

Selected Abstracts

An immunohistochemical study of the triangular fibrocartilage complex of the wrist: regional variations in cartilage phenotype

JOURNAL OF ANATOMY, Issue 1 2007
S. Milz
Abstract The triangular fibrocartilage complex (TFCC) transmits load from the wrist to the ulna and stabilizes the distal radioulnar joint. Damage to it is a major cause of wrist pain. Although its basic structure is well established, little is known of its molecular composition. We have analysed the immunohistochemical labelling pattern of the extracellular matrix of the articular disc and the meniscal homologue of the TFCC in nine elderly individuals (age range 69,96 years), using a panel of monoclonal antibodies directed against collagens, glycosaminoglycans, proteoglycans and cartilage oligomeric matrix protein (COMP). Although many of the molecules (types I, III and VI collagen, chondroitin 4 sulphate, dermatan sulphate and keratan sulphate, the oversulphated epitope of chondroitin 6 sulphate, versican and COMP) were found in all parts of the TFCC, aggrecan, link protein and type II collagen were restricted to the articular disc and to entheses. They were thus not a feature of the meniscal homologue. The shift in tissue phenotype within the TFCC, from a fibrocartilaginous articular disc to a more fibrous meniscal homologue, correlates with biomechanical data suggesting that the radial region is stiff and subject to considerable stress concentration. The presence of aggrecan, link protein and type II collagen in the articular disc could explain why the TFCC is destroyed in rheumatoid arthritis, given that it has been suggested that autoimmunity to these antigens results in the destruction of articular cartilage. The differential distribution of aggrecan within the TFCC is likely to be reflected by regional differences in water content and mobility on the radial and ulnar side. This needs to be taken into account in the design of improved MRI protocols for visualizing this ulnocarpal complex of the wrist. [source]

Carpal bone movements in gripping action of the giant panda (Ailuropoda melanoleuca)

JOURNAL OF ANATOMY, Issue 2 2001
HIDEKI ENDO
The movement of the carpal bones in gripping was clarified in the giant panda (Ailuropoda melanoleuca) by means of macroscopic anatomy, computed tomography (CT) and related 3-dimensional (3-D) volume rendering techniques. In the gripping action, 3-D CT images demonstrated that the radial and 4th carpal bones largely rotate or flex to the radial and ulnar sides respectively. This indicates that these carpal bones on both sides enable the panda to flex the palm from the forearm and to grasp objects by the manipulation mechanism that includes the radial sesamoid. In the macroscopic observations, we found that the smooth articulation surfaces are enlarged between the radial carpal and the radius on the radial side, and between the 4th and ulnar carpals on the ulnar side. The panda skilfully grasps using a double pincer-like apparatus with the huge radial sesamoid and accessory carpal. [source]

Clinical anatomy of the dorsal venous network in fingers with regard to replantation

CLINICAL ANATOMY, Issue 1 2007
A. Sukop
Abstract The arterial system of fingers is anatomically well described, and so, usually no difficulties arise during its preparation and the making of anastomoses in replantation surgery. Difficulties may occur, however, during manipulation in the dorsal vascular bed of fingers, known only as a random venous network. There are minimal references to its existence and the location of its valvular apparatus. Using a microscopic preparation, a contrast staining, and a histological assessment, topographic relations and the course of veins of the dorsal venous network, as well as the existence and location of their valvular apparatus, was investigated on 72 three-phalanx fingers. The specimens were either harvested from fresh cadavers or traumatically amputated. We found that veins of rather significant caliber predominantly run along the dorsal aspect of the finger on both the radial and ulnar sides above the proximal phalanx of three-phalanx fingers. Proximally, venous systems of respective neighboring fingers connect in the interdigital space. The valvular apparatus was found at all levels ranging from metacarpophalangeal joints to the distal phalanx. The valves were always located distally from the confluence of two veins. Aside from this confluence, the existence of valves was not observed. The exact description of architecture of this venous system, in practice, contributes to faster orientation, better preparation, and the creation of safer anastomoses of these structures, and thus, to an increased success of replantation. Clin. Anat. 20:77,81, 2007. © 2006 Wiley-Liss, Inc. [source]