Cryotherapy

Physiological Effects

Neuromuscular Effects

Metabolic Effects

Haemodynamic Effects

Therapeutic Effects

PAIN RELIEF

INCREASED MUSCLE STRENGTH AND PREFORMANCE

REDUCE SWELLING / INFLAMMATION

COLD INDUCED VASODILATION (CIVD) occurs when cold is applied for longer periods of time: mediated by axon reflex in response to pain of prolonged cold

IMMEDIATE VASOCONSTRICTION decreases blood flow both locally and systemically by:

  1. Direct activation of smooth muscle of blood vessels by cutaneous thermo-receptors
  2. Decreased release of vasodilator mediators (histamine and prostaglandins)
  3. Activation of sympathetic nerves (control of smooth muscle in blood vessels)
  4. Increased blood viscosity

DECREASED NERVE CONDUCTION VELOCITY
Occurs when cold is applied for >5 minutes (after 5 minutes of cold it can take 15 minutes for conduction velocity to recover, after 20 minutes of cold it can take 30 minutes to recover)
Greatest effect on myelinated and small fibres e.g. A-delta fibres (pain-relief effect)

INCREASE PAIN THRESHOLD
Activate spinal cord gate theory indirectly by reduction in muscle spasm by slowing conduction velocity of pain fibres

CHANGES IN MUSCLE STRENGTH
Isometric strength increases immediately after ice massage for 5 minutes
Strength and endurance decrease after initial 30 minutes of applying ice
Gradually recovers to above pre-cooling strength over next 2 hours

DECREASED SPASTICITY (excessive increased tone associated with upper neutron lesion e.g. stroke)
Decreases gamma motor neuron and Golgi tendon organ activity
Cold for 10-20 minutes can produce effects lasting 60-90 minutes

LEWIS HUNTING RESPONSE: dilation is replaced by another episode of vasoconstriction

DECREASED METABOLIC RATE
Used to control inflammation
Inhibits activity of cartilage-degrading enzymes (e.g. collagenous, elastase, protease associated with RA)
Activity stops at joint temperature of 30 degrees
Not recommended when healing is delayed

REDUCE SPASTICITY IN UPPER MOTOR NEURON LESIONS

Conta-indications

Precautions

Adverse Effects

Peripheral vascular disease over the extremity

Arteriosclerosis

Raynaud's disease

Cryoglobulinemia: can occur with RA and SLE (reaction to cold causing change in blood viscosity

2-3 days post steroid injection

Over an open wound

Skin hypersensitivity

Poor skin sensation

Directly over a superficial main branch of a nerve

Cardiac disease and altered blood pressure

Over anterior neck (corotid sinus to brain)

Temporary or permanent nerve damage

Unwanted vasodilation

Tissue death resulting from freezing tissue (occurs when tissue temperature reaches 15 degrees)

Decrease extensibility of collagen-> joint stiffness

Ice-burn

Increase peripheral vascular resistance and blood pressure

Types

Ice baths vasoconstriction reduces effect of DOMS / lactic acid to facilitate recovery
Cochrane review: some evidence that cold water immersion reduces DOMS after exercise compared with rest or no intervention, insufficient evidence to conclude on other outcomes or for other comparisons

Ice massage moving ice over area using slow circular motion. Can be used for neurological facilitation

Cold compression unit pumps water and air in a sleeve wrapped around patient's limb, compression is applied by intermittent inflation of sleeve with air

Vapocoolant spray brief and rapid cooling by evaporation

Ice packs crushed ice in plastic bag and wrapped in a damp towel works better than cold packs as it has a higher specific heat capacity than gels-> more aggressive cooling

Contrast baths

Advantages
Promotes pain relief and increased flexibility
Avoid risk of increasing oedema
Challenges / trains vascular system
Useful for chronic oedema, hypersensitivity with complex regional pain syndrome, sub-acute trauma

Disadvantages
Limb in a dependant position
Some people don't tolerate the cold
Lack of research evidence

Combination of heat and cold: alternate immersion in hot and cold baths

POLICE

Compression

ELevation

Ice

Optimal loading

Protection