Sports Massage – The Process Of Soft Tissue Repair: The Acute And Sub-Acute Phases

In this first of two blogs on soft tissue dysfunction, we are looking at the acute and sub-acute stages of soft tissue repair.

When a sports massage therapist has a client with soft tissue damage, they should make sure both the treatment and post-care advice is appropriate to the level of injury and stage of recovery.

What are the three phases of recovery for soft tissue?

All types of tissue go through three stages of recovery:

1. Acute phase, inflammatory: 3-7 days post-injury
2. Sub-Acute phase, repair: 3-7 days to 3-6 weeks post-injury
3. Chronic phase, remodelling: 3-6 weeks to up to 2 years post-injury

Note: the times are a rough guidance only. Other factors include how severe the injury is and where it is on the body. Areas that are harder to rest, such as the lower back and legs, tend to remain in the acute stage for longer.

THE ACUTE PHASE

Lasting for up to a week, the acute phase involves inflammation in the injury site, as the body looks to repair the damage.

What causes inflammation?

When we injure ourselves, our immune system releases chemicals to protect the body, causing inflammation. The inflammatory response is designed to be therapeutic, protecting the tissue while it gets repaired.

Inflammation has five cardinal signs and symptoms, as follows:

1. Pain
2. Swelling
3. Heat
4. Redness
5. Reduced range of motion of loss of function

Rather than automatically being see as a negative, these five signs should be considered evidence that the body is working through the healing process.

What causes redness and heat?

Redness and heat are caused by damage to the capillaries around the injury. To limit blood loss, the body will initiate vasoconstriction of the blood vessels. With no oxygenated blood coming into them, the cells will die and release chemicals that cause redness and heat.

What causes swelling and pain?

Meanwhile, fluid leaving the blood vessels and entering the tissues carries with it essential nutrients, oxygen, white blood cells and platelets. Although this is part of the healing process, it also causes swelling and pain as pressure is exerted on the nerve endings, which may already be a source of pain having been damaged by the injury itself.

What is the sticky matrix?

The platelets then become sticky and release chemicals to activate thrombin. This is an enzyme that converts fibrinogen in blood plasma into fibrin, which helps to create a ‘sticky matrix’ – a kind of mesh that traps dead cells and plasma to form a blood clot.

Anything that escapes this sticky matrix is targeted by white blood cells and lymphocytes, which also fight infection through the phagocytosis process.

THE SUB-ACUTE PHASE

The repair phase, lasting up to approximately six weeks, depending on the severity of the injury.

Why are new blood vessels formed?

As blood vessels supply nutrients and oxygen to cells, it’s important for the body to form new blood vessels during the sub-acute stage, as these will help to repair the damage caused by the injury.

What are fibroblasts?

These are cells that produce collagen. They attach themselves to the sticky matrix; the collagen then contracts to pull the wound together, resolving the damage caused to the tissues.

What are the potential problems of this healing process?

The fibroblasts arrange themselves in response to the tensile stresses that the tissue encounters. Tensile stress can come from any direction, but if there is not enough applied to the tissues, the collagen formed will be random, causing adhesions and irregular scar tissue.

If this happens, the tissue will be repaired but with potentially limited functionality. This can mean that the injured person doesn’t regain the full use of the area; it can also increase the chance of further injury in the same place.

In a follow-up blog, we will look at the chronic stage of soft tissue repair.