Tutorial questions Flashcards
Describe each stage of bone fracture repair
4 main stages:
Haematoma formation (inflammatory stage): haematoma forms around fractured site, white blood cells remove debris, preparing for healing.
Callus formation: Fibrocartilaginous callus forms internally between the bone ends and externally as a surrounding collar.
Fibroblasts and chondroblasts produce cartilage and fibrous tissue, stabilising the break.
The cartilage callus is replaced by cancellous bone through ossification.
Osteoclasts and osteoblasts reshape the bone, ensuring it regains its original structure and strength.
effect on using fixation plates for bone repair
stress shielding-
fixation plates bear the most of the load instead of the healing bone.Wolff’s Law- bone remodels in response to stress- reduced stress will lead to bone weakening. The bone loses mineral desnity because it is not being sufficiently loaded- austronauts experiencing bone loss in microgravity immobilised bone works by reducing mass. The bone may struggle to support normal loads.
Atrophy- shrinkage of bones sue to lack of stimulation.
Identify and describe the biomechanical properties
of the two different types of bone evident in the
right femur (i.e. leg bone)
Cortical bone- forms the outer layer of the femur. I is dense, solid and composed of osteons. High compressive strength, high tensile strength and low porosity making it stiffer and less flexible- maintains femur’s shape. Can endure repeated stresses over time. Cancellous bone- found at the ends of the femur, within the medullary cavity. Porous, honey- comb. High energy absorption helping distribute loads and absorb impact reducing the risk of fractures. Flexible, allowing to withstand multidirectional forces. Allows for bone remodelling and blood cell production, responds to mechanical stress by adjusting density.
