What is an injury?

Once tissue is injured the process of healing begins immediately.

The healing process can be divided into 3 distinct phases: the inflammatory phase, the Proliferative phase, and the remodelling phase. All of which will overlap.

The inflammatory stage (Acute) starts within hours and will continue for up to 5 days.

The proliferate phase (Sub-acute) will start form the fifth day and continue for up to 3 weeks.

The remodelling phase can start from the first week and can last from 6mths to 1-2 year.

Stage 1 - inflammatory stage

Typically in a traumatic event injured blood vessels become deprived of oxygen and die. Before repair and regeneration can occur, debris must be removed.

Within the first 5-10 mins the vessels will constrict blood flow (to stem bleeding) but this is rapidly replaced by dilation. The first 24-36 hours you will see the area swelling. This is when the body has dilated its blood vessels to allow a clean up of the debris. Chemicals (histamine) are released and collectively work to increase capillary width and decrease capillary density (allows substances to travel through). However this increase in blood flow can act as an irritant and produces pain and loss of function.

This release of chemicals attracts natural defence cells (chemotaxis). This leads to migration of certain white blood cells (leukocytes) the two most predominant are neutrophils (1st to injury site neutralize harmful bacteria) and macrophages (engulf bacteria and dead cells). These clear the area for new cells to grow and arrive within 72hours and remain for a weeks.

Once cleansing has been achieved the damaged area can begin to sprout new capillaries to bring blood to the region. Re-growth can begin.

Stage 2 - proliferation

Repair and regeneration depend on three major factors: elimination of debris, the regeneration of endothelial cells, and the production of fibroblasts, which compose connective tissue throughout the body and form the basis of scar tissue.

Stimulated by a lack of oxygen, capillary buds begin to form in the walls of the intact vessels. From these buds grow immature vessels that form connections with other vessels. As these vessels become mature, more oxygenated blood is brought to the injured area. Fibroblasts migrate to the injury and form collagen substances (type 3 immature collagen), often within a few days. New protein fibres are laid down in a haphazard manner and are therefore weak and does not possess a lot of tensile strength

Stage 3 - Maturation

This is the remodelling phase where scar tissue strengthens to form type 1 collagen. This happens through being subjected to controlled strain in a functional pattern. As this stage can last for up to 2 years the area is in a vulnerable state and has a high re-injury chance. The risk is reduced by providing additional stability with strapping, strengthening of the muscle surrounding the joint and proprioceptive exercise to increase the sense of joint position. The tissues need to be stressed in the direction in which the tissues are being used otherwise you will have loss of function and the scar will be less pliable.

Once laid down, the scar tissue begins to contract to close the injury site. It is vital to use stretching to increase pliability of the scar tissue and reduce the chances of range loss.

Inflammation is part of the healing process but what the ice bath does to help with the healing and recovery is it helps to prevent excessive inflammation, which can lead to reduced ROM. The cold of the ice bath does promote healthy blood flow to the muscles because it reduces the amount of histamines present in the blood. Histamines, in high levels are detrimental and lowering them during recovery can help to increase recovery time.  Controlled amounts of time in an ice bath can be helpful. Excessive time spent icing/ice bathing would in fact be counter-intuitive and cause damage due to high levels of decreased oxygen.

Treatments throughout the stages

Stage 1 (3-5 days)

PRICE

Protection, Rest, Ice, Compression, Elevation

For protection crutches, strapping etc. can be used

Rest from anything painful, you can try to achieve very light range of motion exercises as this aids healing, if you sustained your injury through one sport you may be able to try an alternative which off loads the injury site. Its important to keep going as much as possible. If the injury is severe then complete rest is advisable.

Ice - 20 minutes every two hours with compression

Compression - strapping to decrease swelling

Elevation - helps to get rid of debris by encouraging flow to the next lymph nodes (lymphatic system gets rid of waste).

If swelling is stubborn and still present after 3 days massage techniques to help get rid of swelling can be used. Ultrasound may also be used to stimulate debris removal and regeneration through small sound waves causing vibration among tissue (dislodge stubborn debris).

Very light active range of motion exercises if pain free. A therapist may use passive range of motion to keep range of motion.

All activities during this stage should be pain free.

Stage 2 (3days-3 weeks)

In this stage the injury may allow contrast hot and cold to encourage blood supply for regeneration. This should only be done when bleeding has stopped.

Massage can be used to keep new tissue layout in a longitudinal pattern. It can also help reduce soreness, increase range of motion and decrease size of scar tissue.

Ultrasound is still a useful tool to help strengthen the new tissue.

Light stretching is allowed with progressive strengthening programme and proprioceptive exercises

Stage 3

Heat treatment is helpful to keep tissue pliable. Massage is also beneficial. Stretching and strengthening should have started to progress and later become sport specific.