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Abstract Bone is one of the few organs able to undergo spontaneous regeneration, as the entire anatomical structure is restored to the state that existed prior to injury. Fracture healing can be diVided conveniently into stages which makes the overall picture clearer and these stages are; stage of impact, stage of induction, stage of inflammation, stage of soft call LIS, stage of hard call us and f i naIly the stage of remodeling. The essential achievement in fracture healing is the creation of a bony bridge between the two fragments, so that they move as one and the bony bridge is then modified to suit the particular functional demands Which will be placed upon it. Considerable debat surrounds the role of haematoma in fracture healing but the general feeling is that haematoma itself does not playa significant physiological stimUlatory role in the repair of fractures. There are two types of fracture healing, the first is the primary type bone healing which is somewhat artificial in that it is Possible only With rigid internal fixation and excellent anatomical Position, the second is the standard process of healing that is normally observed in th. non-operative managment of fractures. Fracture healing in influenced by multiple factors which are either loc~l or systemic. Among the local factors affecting fracture healing are the degree of local trauma~ the degree of bone loss~ the degree of immobilisation~ the type of bone involved~ the pr~sence of infection~ malignancy or other local pathological conditions. Also important are the vascularity of bone fragments~ the degree of reduction~ distraction as well as the sit~ of fracture and the method o~ fracture therapy. Among the systemic factors that can augment or retard fracture healing are the age of the patient~ as well as the nutritional and hormonal states of the patient. In this respect~ it is worthy to mention that normal amounts of all hormones contribute toward fracture healing and that aberrations in hormonal levels, either excesses or deficiencies; can delay bone healing. Bone grafting is used to establish an additional source of osteogen~sis and to act as a scaffold for the formation of new bone. A bone graft has an inductive effect on local tissues ~ndcan lead to the formation of new bone. Bone grafts may be one of three, autogenous~ homogenous -139- |