Physiology 101
Trauma > inflammation
- Trauma, either through injury or surgery, causes inflammation and one of the first things that happens is vasodilation, which causes bleeding, bruising, hematoma;
- there is loss of Endothelial integrity, which leads to extravasation of fluids into the extracellular space, causing oedema;
- and release of inflammatory enzymes, like bradykinin and serotonin, which causes pain.
The effects of cold
- Cold immediately causes vasoconstriction, which limits the amount of bruising and hopefully bleeding and hematoma;
- It reduces the amount of extravasation of fluids, and hence reduces oedema;
- and the cold slows down cellular metabolism as well as cellular enzyme activity and so reduces pain.
What many people do not realise...
The vasoconstrictive effect of cold reaches a maximum at about 15ºC, below 15ºC there is aparadox vasodilation, which is largely explained by paralysis of the Endothelial-smooth muscles and possible a nerve conduction block of the nerve fibres that causes vasoconstriction.
Hilotherapy is therefore a much more effective therapy than ice, gel packs and ice packs... because with ice and a temperature that is below 15ºC the positive effects of cold are negated.