True about fracture healing except -
Ans. is 'c' i.e., Compression at fracture site cause nonuniono Compression at fracture site improves healing by inducing callus formation.o All other options are true.Factors affecting fracture healingo Both local and systemic variables influcence the rate and degree of fracture healing. When normal healing occurs, but at a slower rate than usual, it is termed delayed union. A complete cessation of the healing process, in which fibrous tissue is never replaced by bony matrix, is termed nonunion.Systemic Factors Affecting Fracture Healingo Age: Young patients heal rapidly and have a remarkable ability' to remodel and correct angulation deformities. These abilities decrease once skeletal maturity is reachedo Nutrition: A substantial amount of energy is needed for fracture healing to occur. An adequate metabolic stage with sufficient carbohydrates and protein is necessary.o Systemic Diseases: Disease like osteoporosis, diabetes, and those causing an immunocompromised state will likely delay healing. Illnesses like Marfan's syndrome and Ehlers- Dnalos syrndrome cause abnormal musculoskeletal healing,o Hormones: Thyroid hormone, growth hormone, calcitonin, and others play significant roles in bone healing. Corticosteroids impede healing through many mechanisms.Local Variables Affecting Fractures Healingo Type of bone : Calcellous (spongy) bone fractures are usually more stable, involve greater surface areas, and have a better blood supply than do cortical (compact) bone fractures. Cancellous bone heals faster than cortical bone.o Soft tissue interposition : Impaires healing of fracture.o Pattern (type of fracture): Spiral fracture unite faster than oblique fractures, which in turn unite faster than transverse fractures.o Compression at fracture site: Improves healing by inducing callus formation.o Degree of Trauma: The more extensive the injury' to bone and surrounding soft tissue, the poorer the outcome. Mild contusions with local bone trauma will heal easily, w'hereas severely comminuted injuries with extensive soft tissue damage heal poorly.o Vascular Injury inadequate blood supply impairs healing. Especially vulnerable areas are the femoral head, talus, and scaphoid bones.o Degree of Immobilization: The fracture site must be immobilized for vascular ingrowth and bone healing to occur. Repeated disruptions of repair tissue, especially to areas w'ith marginal blood supply or heavy soft tissue damage, will impair healing.o Intraarticular Fractures : These fractures communicate with synovial fluid, which contains collagenases that retard bone healing. Joint movement will cause the fracture fragments to move, further impairing union. When intraarticular fractures are comminuted, the fragments tend to float apart owing to loss of soft tissue support.o Separation of Bone Ends : Normal apposition of fracture fragments is needed for union to occur. Inadequate reduction, excessive traction, or interposition of soft tissue will prevent healing.o Infection : Infections cause necrosis and edema, take energy away from the healing process, and may increase the mobility of the fracture site.o Local Pathology: Any disease process that weakens the musculoskeletal tissue, like osteoporosis orosteomalacia, may impair union.
Nutrition affects healing
Stable fixation promotes healing
Compression at fracture site causes nonunion
Hormonal status may affect healing
Anatomy of Bone & Fracture Healing