1. Aetna considers any of the following heating devices medically necessary durable medical equipment (DME) for the following conditions for which the application of heat in the form of a pad is therapeutically effective:

   1. Electric heating pads; or
   2. Hot packs (hydrocollator units); or
   3. Moist heat packs (steam packs).

   Note: General indications and contraindications to therapeutic heat are presented in the appendix.

   Aetna considers heat lamps medically necessary DME for conditions for which the application of heat in the form of a lamp is therapeutically effective.

   Aetna considers portable paraffin baths medically necessary DME for members who have undergone a successful trial period of paraffin therapy and the member's condition (e.g., severe rheumatoid arthritis of the hands) is expected to be relieved by the long-term use of this modality. Standard (non-portable) paraffin baths are not considered appropriate for home use.

   Note: The following heating devices do not meet Aetna's contractual definition of DME because they are not primarily medical in nature and are normally of use in the absence of illness or injury:

   1. Heat and massage foam cushion pads; or
   2. Portable room heaters; or
   3. Hot water bottles.

   Note: Aetna does not cover any of the following heating devices because they are institutional equipment that is not appropriate for home use:

   1. Ultrasound devices; or
   2. Short wave diathermy devices; or
   3. Microwave diathermy devices.

   These modalities must always be performed by or under the supervision of a qualified physical therapist.

2. Aetna considers mechanical heated water-circulating pads and pumps experimental and investigational because they have not been proven to produce outcomes superior to standard hot packs or electric heating pads. Passive hot and cold therapy is considered medically necessary for indications outlined in CPB 297 - Cryoanalgesia and Therapeutic Cold.

3. Aetna considers infrared heating pad systems experimental and investigational because they have not been proven to have a therapeutic effect on any conditions for which they were developed. See also CPB 604 - Infrared Therapy.

Note: Usually, no more than one heating device is considered medically necessary for each medical condition. Requests for multiple heating devices are subject to medical review.

Application of heat results in the production of hyperemia, induction of reflex vasodilation, and acceleration of metabolic processes.  Heating devices (fomentation devices) have been used for a variety of indications.  General indications for therapeutic heat include pain, muscle spasm, contracture, tension myalgia, hematoma resolution, bursitis, tenosynovitis, fibrositis, fibromyalgia, superficial thrombophlebitis, and collagen vascular diseases.  General contraindications and precautions for therapeutic heat include acute inflammation, trauma, or hemorrhage; bleeding disorders; temperature insensitivity; inability to communicate or respond to pain; poor thermal regulation (e.g., from neuroleptics); malignancy; edema; ischemia; atrophic skin; and scar tissue.

Hot Packs:

Hot packs, also known as hydrocollator packs, warm tissue by conduction.  They typically consist of canvas bags filled with silicon dioxide that absorbs many times its own weight in water.  Hot packs are immersed in a hot water bath, and are removed from the bath when needed, wrapped in six to eight layers of toweling or an insulating cover, and applied to the patient.  To avoid scalding, excess water should be drained from the pack and the covering towels or pad should be checked for excessive dampness. The packs cool slowly and can remain warm for 30 or more minutes.

Electric heating pads and circulating water-heating pads are alternatives to hot packs.  Because electric heating pads and circulating water-heating pads do not cool spontaneously, use should be limited to 20 minutes to avoid the risk of burns.  There is no evidence that the use of circulating-water heating pads provide superior outcomes, in terms of enhancing recovery of function, compared to hot packs or electric heating pads.

Hot packs may be preferred over heat lamps in instances where the patient feels that radiant heat dries their skin, or where the patient prefers moist heat.

In uncomplicated cases, heat treatments of this type, as well as paraffin baths and infrared treatments with heat lamps, may not require the skills of a physical therapist.

Heat Lamps:

Heat lamps warm tissues by conversion (i.e., by converting radiant energy to heat).  Heat lamps often use 250-watt incandescent bulbs and are usually placed about 40 to 50 cm from the patient.  Because ordinary incandescent light bulbs produce large amounts of infrared energy, special infrared sources (e.g., quartz, tungsten) are seldom necessary.  Heating rates and maximum temperatures are controlled by adjusting the distance between the lamp and the patient.  Heat lamps may be preferred over hot packs where the patient is difficult to position or cannot tolerate pressure.   Heat lamps may also be easier to use than hot packs.

Paraffin Baths:

Paraffin baths are primarily used to treat contractures, particularly for patients with rheumatoid arthritis, hand contractures, or scleroderma.  The typical paraffin bath consists of a container filled with approximately a 1:7 mixture of mineral oil and paraffin maintained at 52°C to 54°C.  Although paraffin-oil mixtures can be heated in a double boiler or stove, small commercial units are available for home use, which have the advantages of ease of use and increased safety.  The patient may either continuously immerse the treated part for 20 to 30 minutes, or may repetitively dip and remove the treated area from the paraffin.

Ultrasound:

Ultrasound is sound above the limits of human hearing.  The therapeutic effects of ultrasound result from the conversion of sound to heat energy.  Ultrasound diathermy typically employs frequencies between 0.8 and 1 MHz.

Ultrasound diathermy is considered a deep heating modality in that most absorption occurs far beneath the skin.  It is most commonly used to treat tendonitis and bursitis, musculoskeletal pain, degenerative arthritis, and contractures.  Maximal heating may be limited by deep tissue factors and not by skin tolerance.  Ultrasound may be applied directly by placing the applicator on the skin, or indirectly by immersing the body part and applicator in a water-filled container.

Because of the importance of appropriate technique and inherent dangers, ultrasound diathermy should be applied by a trained attendant and the devices are not appropriate for unsupervised home use.

Short-wave Diathermy:

Short-wave diathermy uses radio waves to heat tissue conversively; tissue is heated by the actions of a rapidly alternating electrical field.  Because of the inherent risks involved in application of this deep heating modality, short wave diathermy machines are inappropriate for unsupervised use at home.

Microwave Diathermy:

Microwave diathermy involves the use of microwaves for heating tissues, and offers an advantage over short-wave diathermy in treating small areas in that they can be relatively easily focused.  However, microwaves generally do not penetrate tissue as deeply as short waves.

Microwave diathermy has been used primarily to heat relatively superficial muscles and joints.  Microwave diathermy is used relatively rarely, and indications for which microwaves would be appropriate often are treated with superficial heat, short-wave diathermy, or ultrasound.  Because of the importance of appropriate application technique and the inherent risks of this deep heating modality, microwave diathermy machines are inappropriate for unsupervised home use.

Infrared Heating Pads:

An infrared heating pad system consists of a pad or pads containing mechanisms (for example, luminous gallium aluminum arsinide diodes) that generate infrared (or near infrared) light and a power source.  According to Medicare Durable Medical Equipment Carrier (DMERC) policy, there are no indications for which these devices have been demonstrated to have any therapeutic effect.  DMERC considers these devices and any related accessories not medically reasonable and necessary.  As a heating device, infrared heating pads have not been shown to be more effective than electric heating pads and hot packs, despite their greater cost.

Appendix

General indications for therapeutic heat include pain, muscle spasm, contracture, tension myalgia, hematoma resolution, bursitis, tenosynovitis, fibrositis, fibromyalgia, superficial thrombophlebitis, and collagen vascular diseases.

General contraindications and precautions for therapeutic heat include acute inflammation, trauma, or hemorrhage; bleeding disorders; temperature insensitivity; inability to communicate or respond to pain; poor thermal regulation (e.g., from neuroleptics); malignancy; edema; ischemia; atrophic skin; and scar tissue.