Almost every fun activity (riding, skiing, base jumping...) has its downside - a risk of injury!

Knowing how your body responds to injury and how it heals, helps you to understand the best ways to help it . Next week, I'll cover what to do to help your body heal as efficiently as possible. Take a look at the slides below for more detail on what happens when you get injured - whatever or wherever the injury, the body's response is basically the same:

Immediate Response Phase

The immune system is constantly primed to respond to any injury: injury releases alarmins (antigens and mediators). Alarmins interact with immune cells to initiate the inflammatory responses. 

1. Blood clotting at the site of injury: Platelets and clotting factors stop bleeding, seal the site from the outside world using a plug of fibrin and also create a barrier between the injury and the rest of the body.
2. Histamine causes vasodilation and increased permeability of the local capillaries to allow entry of platelets to seal the site, white blood cells that are sent to clear dead tissue and pathogens by phagocytosis and antimicrobials to protect from infection.
3. Increased permeability also results in excess fluid loss into the tissues.
4. This is where ice packs and compression can help (see next post for the PRICE protocol) to limit further tissue damage (bruising etc.) from leakage into the surrounding areas.
5. Local Lymph node actvity is increased to drain waste products safely away.

N.B. Blocking this initial response with anti inflammatory drugs will interfere with this vital protective stage : do not take before at least two hours after injury e.g. paracetamol, aspirin, ibuprofen (unless instructed to do so by a medical professional)

• The body also very quickly releases a counter-inflammatory reaction to control and limit excess inflammatory response (using regulatory T cells, anti-histamines etc.) 
• Again, this is where ice packs and compression can help (see next post for the PRICE protocol).

Initial healing:

Healing of the damaged tissues by proliferation:

1. Collagen deposition and granulation tissue formation by fibroblasts, chondroblasts or osteoblasts, depending on the tissue, to form a new, provisional matrix of tissue. These cells tend to contract in order to close the gaps i.e. wounds.
2. Excessive activity at this stage can lead to scarring. Conversely, too slow laying down of new tissue also leads to scarring as the second phase is not activated.
3. 

Second phase healing:

Remodelling

1. Fibroclasts, chondroclasts, osteoclasts etc. nibble away at the new tissue and programmed cell death (apoptosis) removes excess cells that are no longer needed.
2. Collagen is realigned under the lines of tension or stress created by using the injured area again.

• This is when external scarring can be minimised by massage etc.
• And internal scarring is minimised by careful exercise and rehabilitation.