To physiotherapists colleagues, what is the penetration depth of SWD?

Question

To Physical Therapists world wide!

What is the scientific rational behind this?

What will happen if we give for so many sesstions will that be more beneficial?

I need ur URGENT help a bout short wave diathermy plz....

Answer 1

Depth of Penetration

Prolonged externally applied cold is more penetrating and long-lasting than externally applied heat. The circulation vasodilates in response to heat. Externally applied heat increases blood flow to an area, but the heat is absorbed by the circulation and carried away, which results in minimal penetration. On the other hand, the application of cold causes vasoconstriction, so the circulation is less able to carry away the cold, which results in deeper penetration.

Subcutaneous fat is a barrier against heat exchange because it has low thermal conductivity. If cold is applied for a short time over an area containing significant amounts of fat, there will be little decrease in muscle temperature. However, if the cold has been applied for a longer period (thirty-minutes or more), fat will help depress muscle temperature for a longer period because the fat acts as a gradient that "holds the cold in."

Selecting the Proper Thermal Modality


Criteria for selection of a thermal modality include the

• Nature, location, and extent of the injury

• Desired effects of treatment

• Availability of various modalities


The appropriate modality must produce the desired temperature at the proper location. If vigorous deep heating is indicated (e.g., muscle spasm of a deep muscle, such as the pectoralis minor) and a modality with an inappropriate distribution is selected, the result may be inadequate treatment at the site of pathology and damage to the tissues in the area of peak temperature. Deep heating modalities include ultrasound and shortwave diathermy; superficial heating modalities include hot packs and whirlpool. As discussed, cold tends to be more penetrating than heat. However, specific modes of cold application (i.e., ice packs, ice massage, ice bath) vary in their penetration. Cold applied directly to soft tissue, such as with ice massage and ice bath, tends to be more penetrating than ice applied as a pack.
Application and Dosage. Shortwave diathermy is administered through de vices such as condenser plates, con denser pads, an induction coil, and a monode applicator. The mode of ad ministration determines the depth of heat penetration. Heating tends to occur in subcutaneous tissues and superficial muscles when condenser plates or pads are used. If the modality is used with an induction coil, the highest temperature will be in the superficial and moderately deep muscles. The monode applicator achieves the greatest penetration but is able to heat only a small field.

Dosage depends upon the athlete's heat tolerance. Always tune the instrument to its lowest setting to prevent excessive surges of current, which may occur when an instrument is suddenly turned on and adjusted to a high setting. The correct setting should give the athlete a comfortable sensation of heat.