Let's start off by explaining what hydrotherapy is... Hydrotherapy is in its purest definition is treatment, using water. Hydro- is a word of greek origin, this word literally means water. Hydrotherapy can be using water that is of varying temperature ranges, all the way from ice cold to hot water.
The hydrotherapy that's used in horses depends on injury type:
Cold water is typically used on acute or fresh injuries or any conditions that causes significant inflammation while also helping desensitize the affected area.
Cold causes vasoconstriction of any blood vessels, which means the vessels become more narrow. The narrowing of the vessel causes a restriction of blood flow.
** Don't ever leave cold/freezing ice water on for longer than 20min. with inflammation based injuries as it will actually counteract the therapy and cause vasodilation.
If it is a recent injury, instead use 20 min intervals multiple times through out the day.
Hot water is typically used for chronic injuries without significant inflammation or when trying to relax and warm up muscles.
Heat causes vasodilation of any blood vessels, this means the opposite of vasoconstriction, the expansion of a blood vessel. The bigger the the vessel the more blood that can flow through.
** Heat should never be applied to an acute injury
When an area of the body is injured there is the same sequence of events that occur no matter what; tissue metabolism is altered due to necrosis and apoptosis, altered blood flow and fluid builds up and pools in the affected area (Person & McFarland, 2018). When a cell is damaged or dying, it sends a chemical signal known as histamine to the body in order to cause vasodilation (Rice University & OpenStaxCollege, 2013). All these steps lead to redness, heat and inflammation being born, which is a self-preservation process that has been shown to reduce the extent of an injury as well as initiate repair of the body. Heat, inflammation and pain come in varying degrees associated with the severity of the injury (Person & McFarland, 2018).
When rehabbing a horse's injury, there are different protocols when it comes to the type of hydrotherapy used. This is based on multiple factors such as, the severity of the injury, the patient's temperament, the type of injury and how long it has been there.
Cold hydrotherapy can look like:
Cold Tape
Frozen peas/corn wrapped in a cold wet cloth
A cold wet cloth compress
Frozen water within paper or styrofoam
Instant cold packs
Homemade cold beanie bag
50/50 water and alcohol solution which creates a cooling effect like an ice pack
Garden Hose (Most commonly seen)
Cold water boots
Warm hydrotherapy can look like:
Heating Pad
Thermophores
Paraffin Wax
You can also use a technique called a contrast bathing hydrotherapy. For this, you alternate between a cold and a hot water area. This will essentially act as a pump system to help remove swelling. This can be done by getting two buckets, one cold and one hot and placing a towel within each, then alternating the towel used on the affected area in 10 minute intervals (McIntyre, 2011).
What are the benefits of this?
Hydrotherapy not only allows for the body to heal at a faster but gives a better healing process and quality of horse coming back from injury. This may sound confusing, so I will explain what I mean by this.
Hydrotherapy alters a horse's body response by increasing or decreasing blood flow to an area depending on the temperature range, this in turn changes the repair cycles within it's body. When the water used is cold, as stated above, it creates vasodilation which increases blood flow to and from the heart and lungs, which gets more oxygenated blood cells to flow through the affected area and removes stagnant blood cells faster than if the body were to do this without aid. A constant supply of oxygenated cells means more better faster healing in the initial fazes of healing (Person & McFarland, 2018).
When warm water is applied, it helps to regulate cell metabolism. Heat increases the blood flow away from the heart and lungs but does not increase it going towards the area. The increase in blood cells that are being carried to the area are filled with oxygen and good nutrients , which helps repair damaged cells, slowing deterioration and cell death. Ultimately this leads to cells being able function normally at the affected site, which again means better faster healing than if the body were to try to do it on it's own.
Hydrotherapy also helps with numbing (cold) and relaxing (warm) the area affected which helps with pain relief (McIntyre, 2011). Pain can be a huge inhibitor to the healing process of any injury. When anyone in in pain it can cause spikes in blood pressure and heart rate as well as increase cortisol levels in the blood stream. It has been documented in numerous studies that a raise in cortisol levels can lead to decreased immune function, which can make you more prone to infection, inflammatory complications and overall slowing of the healing process significantly (Serena et al., 2016).
Further more, hydrotherapy can also help with increasing range of motion!! Inflammation creates a ton of fluid in a joint space or affected area limiting range of motion; although it is a good initial response to reduce motion within the affected space in order to avoid causing further damage, in longer term, the evolutionary response is no bueno. After giving an injury site time to heal, it's important to get the joint and surrounding muscles moving in order to preserve strength, muscle elasticity and performance ability. When I say performance, I don't just mean competition abilities, but instead mean the horses natural ability to perform.
References
This information was cited using the following format: The Veterinary Journal
McIntyre, S., 2011. Hydrotherapy , in: Advanced Equine Massage Therapy Manual . pp.10-12 .
Person, McFarland, C., 2018. Can horses do hydrotherapy or water therapy?: Vita Flex [WWW Document]. Vita Flex Pro. URL https://www.vitaflex.com/the-arena/conditioning/water-as-therapy (accessed 9.16.22).
Rice University, OpenStaxCollege, 2013. Tissue injury and aging [WWW Document]. Anatomy Physiology. URL http://pressbooks-dev.oer.hawaii.edu/anatomyandphysiology/chapter/tissue-injury-and-aging/#:~:text=Upon%20tissue%20injury%2C%20damaged%20cells,releasing%20the%20potent%20vasodilator%20histamine. (accessed 9.16.22).
Serena, T.E., Yaakov, R.A., Aslam, S., Aslam, R.S., 2016. Preventing, minimizing, and managing pain in patients with chronic wou: CWCMR [WWW Document]. Chronic Wound Care Management and Research. URL https://www.dovepress.com/preventing-minimizing-and-managing-pain-in-patients-with-chronic-wound-peer-reviewed-fulltext-article-CWCMR (accessed 9.16.22).