Principles of Fracture Healing and Fixation: A Literature Review.

Bone healing is a complex, dynamic process involving a series of well-coordinated stages, influenced by both mechanical and biological factors. The skeletal system, composed of inorganic (36%), organic (36%), and water (28%) components by volume, plays a crucial role in maintaining structural integrity and mineral homeostasis. Bone is classified into two main types based on microstructure: lamellar and woven bone, with lamellar bone being stronger and more durable. Factors such as inflammation, the periosteum, vascularity, and infection significantly impact healing outcomes. Moreover, fracture fixation is fundamental to optimal healing, guided by principles of anatomical reduction, stable fixation, blood supply preservation, and early mobilisation. Perren's strain theory emphasises the importance of strain at the fracture site, which can determine whether primary or secondary healing occurs. Rigid fixation provides an environment which promotes primary bone healing, while flexible fixation promotes secondary healing through controlled motion. Internal and external fixation methods, including plates, screws, and intramedullary nails, offer varying degrees of stability, supporting bone healing. Overall, optimal fracture fixation, combined with an understanding of bone biology, enhances healing and functional recovery.