Cold therapy (cryotherapy) is the application of ice or cold packs to treat sports and soft tissue injuries.
When damage occurs to soft tissue, such as when muscle tears, blood vessels may rupture within the muscle and the injury site begins to bleed internally.
What is the PRICE principle?
The P.R.I.C.E. principle involves all the components that are required to prevent further injury and start the healing process of the damaged tissue. If applied early enough and correctly it can significantly reduce the recovery time of the athlete. Reminder: The letters P.R.I.C.E. are abbreviations for:
- P – Protection
- R – Rest
- I – Ice
- C – Compression
- E – Elevation
PRICE should be applied as early as possible after the injury and continued for at least the first 24-72 hours.
What Happens in the Early Stages of a Soft Tissue Injury
Each component of the P.R.I.C.E. principle plays an important role in limiting swelling and decreasing pain. As a result, the healing process is speeding up.
An increase in blood volume in the area can cause cell death by what is known as secondary hypoxic injury. Thus, every effort should be made to control excessive bleeding.
The inflammation process
Secondary to this, the human body’s response to injury is to start the repair process immediately by protecting the damaged tissue. It does this by increasing pain and swelling and producing a fluid called exudate fluid. The exudate fluid carries all the cells and chemicals in the area to repair the damaged tissue (the body’s own emergency services!).
Damaged cells release a chemical that starts this process and it is essential for healing. However, if this can be limited then recovery times will be shorter. This process is called inflammation and is vital to tissue healing.
Protection of the damaged tissue is vital to prevent further damage and enable the healing process to start efficiently and effectively. There are a number of ways to protect the injured area all with the same aim of limiting further movement. One way this can be achieved is by using a support or splint.
In the early stages, rest is one of the most important components of the cold therapy P.R.I.C.E principle but is often neglected or ignored. It does not only refer to the prolonged period of time that the athlete will be out of action, but also to the immediate period after the injury. An athlete must know when to stop training and allow the injured area to heal, otherwise, repetitive minor injuries can often result in a more severe injury that keeps the athlete out for much longer. This could have been prevented by adequate rest and treatment after the initial injury.
If an injury is sustained during sporting activity some athletes have a tendency to ‘run it off’. This implies that by continuing to participate in the exercise, the injury will simply go away. In fact, in the majority of cases, this is not true and is not advisable.
Pain gate theory
It should be noted that it may be possible that by continuing to exercise with an injury may initially lessen the pain and this is due to a number of factors. During exercise, nerve impulses that are sent due to mechanical stress, such as touch can override the impulses that are sent from the pain nerves – a phenomenon known as “the pain gate theory”.
A good example of this is rubbing an injured area can often make it feel better initially. In addition to physiological factors (nerve overriding), factors such as the player’s mentality and the presence of adrenaline in a sporting situation can all play a part in over-riding the pain from the injury – however, the pain will often come back once the activity has ceased because tissue itself is still damaged and continued activity could, in fact, cause serious further injury (as mentioned earlier).
Complete rest vs active rest
There are a number of different degrees of rest and this depends on the severity of the injury and the type of tissue damaged. For example, a severe ankle sprain that makes walking very difficult needs to be completely rested in the early stage whereas a minor “tweak” of a muscle only requires modified activity, i.e. no action that uses the injured muscle.
Ice therapy, cold therapy also known as cryotherapy, is one of the most widely known and used treatment modalities for acute sports injuries. It is cheap, easy to use and requires very little time to or expertise to prepare. The application of ice to an injury, in the acute phase, can substantially decrease the extent of the damage. It achieves this in a number of different ways:
- Decreases bleeding by closing down the blood vessels (called vasoconstriction).
- Reduces pain (pain gate theory)
- Muscle spasm is reduced
- The risk of cell death (also called necrosis) is reduced. This is because the rate of metabolism is reduced.
Read more on the benefits of cold therapy.
Applying cold therapy & ice burns
Ice is usually applied to the injured site by means of a bag filled with crushed ice which is wrapped in a damp towel. The damp towel is essential as it forms a barrier between the bag of ice and the skin and reduces the risk of an “ice burn”. DO NOT leave the ice on for more than 15 minutes as you could cause an “ice burn”. A more detailed overview of the correct use of ice therapy and the indications for its use are available on the application page.
There are a small number of areas that you should not apply ice to for various reasons. These are the neck, the outside bone of the elbow, the collarbone (upper end), the front of the hip (bony part) and the outer bone of the knee. The reason for this is there is a superficial nerve just below the skin in these areas that can be damaged by applying ice to it. Cold therapy should also not be applied to the area of the kidneys which is just below the ribs towards the back. If in any doubt, consult a professional.
Applying compression to an injured area minimises swelling that forms after an injury in two ways and should be applied for the first 24 to 72 hours from the onset of injury.
How does compression help?
The first way is compressing the injured limb increases the pressure within the tissue thus narrowing the blood vessels (vasoconstriction) and preventing excessive bleeding.
The second way is moderating the amount of fluid that the body produces to protect the injured tissue, called exudate. Although exudate carries the chemicals and cells that help repair the damaged tissue, moderating the amount will significantly reduce the overall healing time.
Compression can be applied through a number of methods. The most effective of these is by using a compression bandage which is an elasticated bandage that simply fits around the affected limb. The advantages of the compression bandage are that it is easy to apply and the elastic material provides sufficient pressure needed to stop the bleeding as soon a possible whilst also allowing for the injured limb to swell slightly.
This is very important because if the compression support is too tight and does not stretch sufficiently then further damage of the tissue can occur, such as cell death (necrosis). An excellent way to monitor whether a compression bandage is too tight is to check the feeling of the tissues either side of the bandage e.g. check for ‘pins and needles’ sensation or skin discoloration/coldness in the toes when compressing an ankle swelling and this is a sign that the bandage is to tight. If this is the case, loosen their bandage or remove the bandage ompletely if the feeling/discoloration does not resolve immediately.
Apply bandages lower and work upwards
Bandaging should always begin distal (furthest away from the heart) to the injured site with each layer overlapping the underlying layer. For example, if you are compressing a thigh, start at the knee and work up towards the hip whereas if you are compressing an elbow, start at the forearm and work up towards the upper arm. The reason for this is to encourage the swelling to move back towards the heart/centre of the body and be reabsorbed. Ideally, compression should be combined with ice therapy and applied with the ice-pack itself, either manually or by wrapping the ice pack in a bandage.
Elevation of the injured limb is the final principle of cold therapy PRICE but is equally as important as the other 4. Elevation allows gravity to drain the fluid away from the injured site. This aids in decreasing the swelling which in turn may decrease the pain associated with oedema (swelling). In lower limb injuries, try and keep the ankle elevated above the level of the hip and in upper limb injuries, keep the arm elevated in a sling or rested on a pillow. Attempts to keep the limb elevated whenever possible should continue for at least the first 48 hours.
Recommended further reading and updates on PRICE:
- Updates on PRICE – Br J Sports Med 2012;46:220-221 doi:10.1136/bjsports-2011-090297
- What is the evidence for PRICE? – J Athl Train. 2012 Aug; 47(4): 435–443.