tailieunhanh - Clinical Surgery in General - part 8

cấu trúc hình ống trung ương, các diaphyses (tiếng Hy Lạp thông qua dia-+ = physis = tự nhiên, tăng trưởng) và kết thúc năm mở rộng, siêu hình học (tiếng Hy Lạp meta - sau), nào Kết hợp các đĩa tăng trưởng, physis, và xương của Bao tấm subchondral các sụn khớp của khớp lân cận. | RESPONSES OF CONNECTIVE TISSUE AND BONE 33 Double limb Single limb Double limb Opposite angle 1 support 1 support 1 support 1 limb support Heel Opp. Heel Opp. heel Toe Heel strike toe 1 L_ off ĩ strike off ĩ I strike 10 30 60 100 Percent of walk cycle Critical event Fig. Phases and events of walking cycle stance phase constitutes approximately 62 and swing phase 38 of cycle. a central tubular structure the diaphysis Greek diet through physis nature growth and an expanded end the metaphysis Greek meta after which incorporates the growth plate the physis and the subchondral bone plate covered by the articular cartilage of the adjacent joint. At skeletal maturity the architecture of the metaphysis becomes homogeneous with loss of the cartilaginous growth plate. Bone is largely composed of type I collagen. It contains cells osteocytes embedded in an amorphous fibrous collagen matrix interspersed with calcium phosphate an inorganic bone salt. Osteoporosis is characterized by a reduction in bone mass. Loss of structural strength may lead to fracture and also affects implant fixation. 2. Bone exists in two forms depending on the arrangement of the collagen fibre and the osteocytes. Immature bone has fibres and osteocytes irregularly arranged. The osteomucin is basophilic and there is a sparsity of calcium. It forms during development of differentiating mesenchyme into the bones of the skull vault mandible and clavicle and when bone is laid down in differentiating mesenchyme as in fracture healing. It also occurs in various bone diseases including osteogenic tumours. Adult bone has the collagen arranged in parallel sheets or bundles as flat plates or in long bones as tubular vascular canals surrounded by concentric systems of cortical bone described in 1689 by the English physician Clopton Havers 1650-1702 . The bone is less compact in the central canal of long bones and is termed cancellous Latin cancellus lattice porous . Most of the skeleton is formed on a .