Local application of heat can provide pain relief and reduce muscle spasm. Most chronic pain patients are aware of superficial heat applied locally in the form of a hot water bottle, or generally in the form of a hot bath or shower.
There are different ways by which heat therapy can be provided. They are broadly classified as:
Superficial heat therapy
- Paraffin wax
- Infrared radiation
- Heat pad
- Hot moist packs
Deep heat therapy
- High frequency currents
- Medium frequency currents
- Low frequency currents
The superficial heat can reach up to 1 to 2 cm depth, while deep heat has the reach beyond this.
This superficial heat produces different response including changes in neuromuscular activity, blood flow, capillary permeability, enzymatic activity and pain.
The deep heat delivers energy directly to deeper tissue, which improves muscular function, blood flow and local reflexes by suppressing sympathetic over-activity.