Bone apposition is best in
D i.e. Osteoblastic activiting in hocoship's lacunae * Since bone itself is a hard and unyielding structure, it can only increase in size by the relatively slow process of appositional growth.* The concept that bone remodelling takes place in small coherent packets of resorption (Howships lacuna in trabecular bone or cutting cone in coical bone) followed by formation is very impoant* In adult skeleton after cessation of skeleton growth, no new lamellar bone formation occurs with out a preceding episod of bone resorption. This constraint applies with in the coex, where the physical lack of space for new bone necessitates preceding resorption, and it also seems to apply to periosteal and endosteal sutfaces(2 * There is, however, debate as to whether periosteal accretion can occur in adults without preceding bone resorption. There are two definte, pathological exceptions to this rule. One is- during the production of callus in a healing fractured where woven bone will form de novo.- after cancllous autograft, where new bone will form directly on to the cancellous graft.* However, the contribution of these circumstances to overall bone homeostasis is likely to be very small.* The total body rate of resorption (is the product of) = number of new cavities eroded in a defined time period Xaverage volume of each cavity. Since the amount of bone eroded in each resorption cavity is constant (roughly), the rate of activation (i.e. rate at which new osteoclastic erosion cavities are begun) determines the total body bone resorption, as well as the rate of total body bone resorption, as well as the rate of total body bone formation.
Osteoblastic activity at the area of stress
Endochondral ossification
Subperiosteal cambian layer
Osteoblastic activity in howship's lacunae