"The Physiology of Sports Injury".

        The acute inflammatory phase discusses how tons of cells are destroyed by trauma and the blood flow is reduced to the injured area.  After a decrease in the blood flow, there is then an increase in the blood flow.  The increase in blood flow causes hematoma in the spaces between cells.  Hematoma can increase the blood flow to the area by over 10 times the regular amount.  Clotting is the result of the decreased blood flow to the areas around the injury.  The clotting then causes the death of cells because they do not have sufficient nutrients (Oxygen) to sustain themselves.  This death of cells is known as “second hypoxic injury.”  Second hypoxic injury also causes cellular breakdown and the release of lysosomes, which are a powerful protein (enzyme) that speed up the breakdown of cells.  There are three sets of chemicals that become active during the acute inflammatory phase; these chemicals are “degenerative enzymes, vasoactive substances, and chemotactic factors.”  Other cells then react to the breakdown of the cells through histamine, leukocytes, bradykinin, and prostaglandins.  Histamine is then used to create vasodilation and increased vascular permeability.  Then leukocytes are attracted to the injury through chemotaxis.  After that, bradykinin creates vascular permeability and releases the prostaglandins.  The prostaglandins then create the pain sensation and a fever around the injury area.  The damaged cells are then eaten through the process of phagocytosis.  The amount of neutrophils near the damaged area greatly increases during the initial hours of inflammation.  Then macrophages eat up the rest of the cellular residue during phagocytosis.  Arachidonic acid becomes the catalyst for creating substances that take part in the acute inflammatory phase.  Basically, the acute inflammatory phase seals off the injury from the other areas of the body, and the process takes about three to four days.         The final phase is the resolution phase, which lasts from after the end of the inflammatory phase until about three or four weeks.  Tissue repairs begins by the movement of polymorph, monocytes, and histocytes to break down the cell debris which will make room for new tissue (scar tissue).         Basically, after the initial injury, decreased blood flow occurs followed by an increase in blood flow.  The increase in blood flow causes Hematoma, which causes clotting.  The clotting then causes the death of cells, which cause the release of lysosomes. The lysosomes cause the cells to break down.  Histamines, leukocytes, bradykinin, and prostaglandin then get rid of the damaged cells (Phagocytosis).  Neutrophils and then macrophages come to help the process of the removal of the damaged cells.  The resolution phase continues to get rid of the dead cells in order to make room for the new tissue to grow.