- Cryotherapy (ice)
- Heat Therapy
- Electrical Stimulation
The physiological effects of heating up the tissue through therapeutic ultrasound causes cell and metabolic activity to increase. There is also vasodilation (widening of the blood vessels) which decreases bloody viscosity and increases the capillary permeability. As well as this, collagen extensibility is increased. There is a decrease in muscle spasm and therefore the muscle relaxes. When the ultrasound produces heat, the soft tissue is warmed up allowing a greater range of motion (ROM), which decreases joint stiffness by decreasing the viscosity of the synovial fluid that is found within the body’s joints. During ultrasound, biological effects are achieved between 40-45°c > 5 minutes. However, ultrasound is inefficient at generating therapeutic heat.
The aim of cryotherapy is to cause analgesia (immediate pain relief). To produce analgesia, the skin temperature needs to be reduced to 13.6°c. The physiological effects of using cryotherapy is to cause vasoconstriction (narrowing of the bloody vessels), decrease blood flow to the area of trauma, increase bloody viscosity and decrease the metabolic rate and has an effect on the peripheral nerves. By using cryotherapy, it helps to remove excess tissue fluid back into general circulation. It promotes repair to the injured area by bringing oxygen, nutrients and other repair substances.
Cryotherapy comes in many forms;
- Dry ice bag
- Ice immersion (ice bath)
- Ice massage
- Freeze gel-packs
- Sprays / Gels
Heat therapy has a negative effect on the early stages of tissue repair as it can exacerbate early inflammation. It will increase oedema (swelling) and increase chances of haemorrhaging. Heat therapy will increase metabolic activity to encourage healing increasing oxygen release and blood supply which leads to an increase in nutrients. There is an increase in nerve stimulation and therefore a decrease in pain. As well as this, there is an increase in extensibility of collagen; leading to precursor to stretching. Therapeutic benefits are gained between 40-45°c.
Electrical stimulation includes using TENS and / or NMES machines.
Transcutaneous Electrical Nerve Stimulations (TENS) is used to stimulate muscles and nerves to strengthen muscles, assist wound healing, relieve pain and reduce oedema. TENS transmits a low frequency electrical impulse and is applied to the skin via lead wires and surface electrodes. TENS can be administered at home, its non-invasive and has no side effects.
Neuromuscular Electrical Stimulation (NMES) is used to strengthen a muscle that has lost most or all ability to contract. It is used with the elderly, people who have suffered a spinal cord injury, stroke or rheumatoid arthritis. It is used to improve the function of the muscle and increase ROM and blood supply.