When tissue becomes damaged, it undergoes cellular transformation. Tissue healing starts with the inflammation phase. In this phase, the cellular tissues remove bacteria and/or debris, and the release of growth factors causes migration and division of cells. The tissue subsequently enters the “proliferative phase,” which will overlap and start even before the inflammatory phase is complete. In this phase, angiogenesis occurs along with fibroblastic proliferation, which will peak up to two weeks post-injury.
These cells are the main cells that lay down the extracellular collagen matrix. This matrix is rich with new blood vessels and many cell types. Growth factors like transforming growth factor beta come into play and the production of type III collagen begins. In the remodeling phase, which can last many months and even upward of a year, type I collagen, which is more resilient and stronger, begins to replace type III collagen. The tensile strength approaches 80 percent and upward over the course of time.
There are local and systemic factors that can disrupt the natural process of healing. Local factors include mechanical aggravation, edema, ischemia and decreased oxygen. Systemic factors include decreased perfusion, metabolic diseases, immunosuppression issues, smoking and decreased nutrition.
When chaos occurs during the inflammatory cascade, the tissue can easily bypass the acute phase and jump right into the chronic inflammatory state, especially if or when the above factors are present. Keep in mind that complaints of symptoms like achy, dull, nagging pain that just won’t go away for months, despite many attempts at conservative care, is probably a good clue for all of us.