What’s Infrared in Physiotherapy? How to Use, Indications

Last updated on March 10th, 2024 at 07:23 pm

Infrared in physiotherapy is a mode of treatment that uses the heating effect of infrared rays to treat a number of musculoskeletal pain. It is widely used in the physical therapy departments for conditions such as low back pain, neck pain, frozen shoulder, and knee pain, and it gives almost instant pain relief. This is why using an infrared lamp in the home is gaining popularity. With its instant relief of pain and ease of use, more and more people are interested in infrared lamp therapy.

But, since it’s a heating device, it has some potential hazards. This article will try to understand the basics of an infrared lamp and how to use it safely at home.

Infrared in physiotherapy

Infrared radiation therapy is a modality widely used in Physiotherapy to manage pain. It is a part of electrotherapy in which an infrared lamp emits IR rays. When our body absorbs these IR rays, they produce a heating effect, which is beneficial in several musculoskeletal pain conditions.

The infrared (IR) is an invisible form of electromagnetic radiation with wavelengths between 780 nm and 1000 μm. It is divided into three different bands (according to standard ISO20473:2007): near-infrared, mid-infrared and far-infrared rays.

• Near-Infrared (NIR, 0.78~3.0 μm),
• Mid-Infrared (MIR, 3.0~50.0 μm) and
• Far-Infrared (FIR, 50.0~1000.0 μm)[1].

If we analyse the infrared spectrum (figure below), the infrared ray lies immediately inferior to the red visible light. This is why it is named infrared rays.   

However, its working principle differs from other heating agents in electrotherapy, such as short-wave diathermy and ultrasonic therapy.

So, what is the working principle of infrared physiotherapy?

Working principle of infrared physiotherapy

The infrared lamp works on the principle of thermotherapy. To understand how it works, we must first understand what thermotherapy is. what are infrared rays?

The therapeutic application of heat is called thermotherapy. The infrared lamp is an instrument that provides thermotherapy. It conducts heat onto our body via radiation. It comes in various types and has different shapes and sizes. With the advent of technology, it is also available in a portable variety. Portable infrared lamps have become very popular, and people keep them home for their needs.

The infrared lamp looks like a standard lamp with a bulb emitting visible red light. However, it’s not the typical red light that radiates from a red neon bulb. The light rays that emit from infrared lamps are called “infrared rays.”  

Types of Infrared Lamps for Physiotherapy

Infrared radiation is produced in two forms: luminous and non-luminous. Absorption depends on the structure, type, vascularity, and pigmentation of the body tissues to facilitate changes within them ¹.

Energy penetration into a medium depends upon the intensity of the infrared source. Maximal penetration occurs with wavelengths of 1.2mm, where the skin is usually opaque to wavelengths of 2mm and more¹. In acute inflammatory conditions, the non-luminous generator may be used because the sedative effect of the rays may be more effective in relieving pain than the counterirritant effect produced by the shorter rays of the luminous generator, which is more effective in chronic lesions.

1. Non-luminous IR generator

As the name suggests, it is a machine that produces only infrared rays without visible light. These kinds of infrared heat generation devices are known as infrared heating pads.

Below is an infrared heating pad you can use for joint pain by plugging it into the power supply.

2. Luminous Infrared generator

The image above is a luminous generator infrared lamp. Notice the bright red light and lamp; it is a luminous generator. The luminous generator produces infrared rays with visible light. An incandescent bulb is used; the luminous generator is more commonly used.

These infrared lamps are straightforward to use; you need to plug them in and use them.

Contraindications of IR therapy

Now that you know the indications, learning where to avoid them is equally important. The following are the contraindications of an infrared lamp.    

1. Pregnancy.
2. Over the metal implants.
3. Knee replacement.
4. Hip replacement.
5. Pacemaker.
6. Eyes.

Also read: TENS can be wonder for Fibromyalgia Pain|Study

Indications of Infrared Lamp Therapy

1. Neck pain: Neck pain is caused by the stiffness of muscles around the neck.
2. Shoulder pain.
3. Frozen shoulder: Frozen shoulder, also known as adhesive capsulitis, is a restriction in the movement of the shoulder joint.
4. Upper back pain: it may be due to muscular spasms or trigger points.
5. Low back pain: Spasm of the low back muscle and chronic low back pain².
6. Knee pain: Osteoarthritis of the knee.

With time, it has become a popular home remedy for such pain. It is very effective in pain relief and easy to handle, which makes people use it for almost all kinds of joint and muscle pain. And, of course, without proper knowledge of its application and potential harm.

Since an infrared lamp is a heating device, it is important to know the correct method of application to avoid potential harm. Prepare yourself before using it. Come to a comfortable position and expose the body part. Remove metal objects like bangles and ornaments from the area of infrared application.

Guide to using infrared lamps safely at home.

Now that we know about infrared lamps for physiotherapy, what if you want to use them in the home? You can use an infrared lamp in the home; it’s handy and easy to use. It is effective in any of the musculoskeletal pain conditions mentioned above.  

Infrared lamps are heating instruments. Therefore, we must follow the proper technique of application. Improper use may result in skin burns and other complications.

I have compiled all the necessary steps and precautions when using this lamp at home in a book. It’s a must-read e-book if you are planning to buy an infrared lamp for yourself and your loved ones or already have one. You can get it on amazon kindle now.  

Common FAQ related to infrared therapy

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Sunit. S. Ekka

Dr Sunit Sanjay Ekka is a physiotherapist in practice for the last 15 years. He has done his BPT from one of the premium Central Government physiotherapy colleges, ie, SVNIRTAR. The patient is his best teacher and whatever he gets to learn he loves to share it on his Youtube channel and blog.