1. TISSUE RESPONSE TO INJURY BTEC Extended Diploma in Sport (Performance and Excellence)

2. 3 Phases of response to injury 3 Phases of response to injury

3. INTRODUCTIONINTRODUCTION Healing is a changing continuum however, to try and understand the healing process researchers have divided the events into three different phases. Healing is a changing continuum however, to try and understand the healing process researchers have divided the events into three different phases. INFLAMMATION INFLAMMATION PROLIFERATION PROLIFERATION REMODELLING REMODELLING

4. TIMESCALE TISSUE HEALING INJURY REMODELLINGPROLIFERATION

5. INJURY This stage represents tissue trauma at the time of injury, before the inflammatory process is activated This stage represents tissue trauma at the time of injury, before the inflammatory process is activated The body attempts to stabilise the injured site by rushing chemicals and cells to the area. The body attempts to stabilise the injured site by rushing chemicals and cells to the area. This has a two fold effect firstly, momentarily This has a two fold effect firstly, momentarilyVASOCONSTRICTIONVASODILATION

6. VASODILATION This is the moment inflammation starts. This is the moment inflammation starts. Blood and its products now slowly flow to the injured area. Blood and its products now slowly flow to the injured area. As they accumulate chemicals are released along with other cells that are attracted into the area. As they accumulate chemicals are released along with other cells that are attracted into the area. The following stages take place; The following stages take place;

7. INFLUX OF; Blood Serum Proteins Platelets Clotting Factors

8. Platelets Bind to collagen Phospholipids Clotting mechanism stimulated Release of Growth factorsFibrinogen Fibrin Plug Fibronectin Cell migration Promotion into wound

9. STAGES CONTINUED Fibronectin binds together FIBRIN and Collagen in a X like formation this acts as a plug to stop the bleeding. Fibronectin binds together FIBRIN and Collagen in a X like formation this acts as a plug to stop the bleeding. Plug is fragile but gives the wound its only strength and is eventually replaced. Plug is fragile but gives the wound its only strength and is eventually replaced. Lymph vessels also damaged therefore fluid accumulates. Lymph vessels also damaged therefore fluid accumulates. Once area becomes stable FIBRINOLSIN is released. Once area becomes stable FIBRINOLSIN is released.

10. ONSET INFLAMMATION First few hours body tries to remove debris from injured area. First few hours body tries to remove debris from injured area. This process started by Neutrophils or Polymorphonucleur Leukocytes (PMN’s) This process started by Neutrophils or Polymorphonucleur Leukocytes (PMN’s) After 5/6hours, the neutrophils begin to be replaced by other cells namely, Mononuclear Phagocytes which predominate cells at injury site within 24/48hrs. After 5/6hours, the neutrophils begin to be replaced by other cells namely, Mononuclear Phagocytes which predominate cells at injury site within 24/48hrs.

11. INFLAMMATION CONT’D PMN’s and macrophages act as phagocytes to remove dead tissue/debris. This is necessary if healing to continue. PMN’s and macrophages act as phagocytes to remove dead tissue/debris. This is necessary if healing to continue. They also release several Growth Hormones and can trigger termination of tissue growth when healing process is complete. They also release several Growth Hormones and can trigger termination of tissue growth when healing process is complete. What then are the signs of inflammation? What then are the signs of inflammation?

12. SIGNS & SYMPTOMS HEAT – due to this increased blood flow HEAT – due to this increased blood flow REDNESS – Vessels enforced and dilated REDNESS – Vessels enforced and dilated SWELLING – due to movement of a fluid into restricted area, possibly a haematoma SWELLING – due to movement of a fluid into restricted area, possibly a haematoma PAIN – caused by swelling that has put pressure on the nerve endings. Also a protection mechanism of the body. PAIN – caused by swelling that has put pressure on the nerve endings. Also a protection mechanism of the body. Not just a feature soft tissue injury. Not just a feature soft tissue injury. Can last 10 minutes – several days. Can last 10 minutes – several days.

13. PROLIFERATION PHASE Transition from removal of debris to formation of new blood vessels and granulation tissue. Transition from removal of debris to formation of new blood vessels and granulation tissue. Angiogenesis happens at a rapid rate during this phase which is important for scar tissue formation as it requires vascular production and supply for further healing to take place. Angiogenesis happens at a rapid rate during this phase which is important for scar tissue formation as it requires vascular production and supply for further healing to take place. Fibroblasts responsible for this new growth and number increases 3/5 days post injury. Fibroblasts responsible for this new growth and number increases 3/5 days post injury.

14. WHAT NEXT Growth factors enter into the area and: Growth factors enter into the area and: Causes local migration of fibroblasts, myofibrils and endothelial cells. Causes local migration of fibroblasts, myofibrils and endothelial cells. Above cells are responsible for development of new capillaries and matrix Above cells are responsible for development of new capillaries and matrix Matrix consists of two components fibrous and non-fibrous. Matrix consists of two components fibrous and non-fibrous. Combination of these fibres provides tensile strength and some resilience to stresses applied to the tissue. Combination of these fibres provides tensile strength and some resilience to stresses applied to the tissue.

15. REMODELING PHASE A number of activities start to recede as area becomes more stable. A number of activities start to recede as area becomes more stable. Capillaries produced during proliferation to promote tissue growth now longer need eventually start to disappear. Capillaries produced during proliferation to promote tissue growth now longer need eventually start to disappear. Cellular changes = visible changes colour returns to skin, swelling goes + sensitivity. Cellular changes = visible changes colour returns to skin, swelling goes + sensitivity. As collagen converted to type 1 becomes more insoluble less resistant to destruction As collagen converted to type 1 becomes more insoluble less resistant to destruction

16. CONT’D Produce more x links strengthening scars structure. Produce more x links strengthening scars structure. Collagen strength is enhanced by the arrangement of these fibres and when aligned in organised parallel fashion = optimal strength. Collagen strength is enhanced by the arrangement of these fibres and when aligned in organised parallel fashion = optimal strength. External forces required to change the arrangement. External forces required to change the arrangement.