Background

This chapter provides four videos about how the occupational therapy (OT) practitioner can use physical agent modalities (PAMs). Specifically, you’ll learn about electrical modalities and ultrasound. We’ll discuss two electrical modalities: 1) Transcutaneous electrical nerve stimulation (TENS) and 2) neuromuscular electrical stimulation (NMES). TENS helps clients manage and decrease their pain perception while NMES helps clients contract muscles to prevent muscle atrophy or to assist in retraining motor control. Ultrasound uses sound to help clients improve healing and regenerate tissue. This chapter also discusses the clinical reasoning and procedures for using each modality and their precautions and contraindications.

With any intervention, it is critical that OT practitioners balance two factors—helping the client achieve their goals and maintaining their safety. With PAMs, it is critical to have 1) a firm understanding of the underlying clinical reasoning for using the modality and 2) a clear understanding of your client’s conditions and the modality’s precautions and contraindications to avoid injury. The chapter on Thermal Physical Agent Modalities goes into more detail about balancing modalities to progress goals while maintaining your client’s safety.

Electric Modalities’ Precautions and Contraindications

This video discusses the electric modalities’ precautions and contraindications, which the OT practitioner must know to ensure their client’s safety.

Video is licensed under CC BY 4.0.

Precautions and Contraindications of Electrical Modalities Video Transcript

Electrical Stimulation Precautions and Contraindications Tips

The purpose of knowing precautions and contraindications before the OT practitioner begins a procedure will ensure their client’s safety.

• Precautions: Yellow Flags
  • Monitor your patients with epilepsy.
  • Avoid contracting your client’s muscles when using in or around healing tissue.
  • Be aware of drug allergies when using iontophoresis.
  • Avoid using where your client has reduced sensation.
  • Avoid using if your client is or may be pregnant.
  • Avoid using if your client is in an early tendon-repair stage.
• Contraindication: Red Flags—Dangerous!
  • DO NOT use if your client has a cardiac pacemaker.
  • DO NOT use if your client has an active cancer or tumor.
  • DO NOT use if your client is transcerebral, transcranial, or transthoracic.
  • DO NOT use over damage or denuded skin.

Transcutaneous Electrical Nerve Stimulation

This video explains transcutaneous electrical nerve stimulation (TENS) for pain management.

Video is licensed under CC BY 4.0.

Transcutaneous Electrical Nerve Stimulation (TENS) Video Transcript

Using TENS Tips

The purpose of using TENS is to provide a strong but tolerable vibration to distract the spinal column from feeling pain. This opens a door so that you can work with your client, pain free, to do things that they couldn’t do before.

• Indication: Pain management
• Protocol: High pulse rate, low pulse width. Place four electrodes in an X over your client’s pain, trigger point, or anatomical structure.
• Description: Your client should feel a sensation like pins and needles or buzzing. DO NOT induce muscle contraction.

This video explains neuromuscular electrical stimulation (NMES), which is using electricity to stimulate muscle contraction. This procedure can be used to prevent muscle atrophy or to assist in retraining motor control.

Video is licensed under CC BY 4.0.

Neuromuscular Electrical Stimulation Video Transcript

Using NMES Tips

The purpose of using NMES is to use electricity to stimulate muscle contraction. This procedure can be used with your clients to prevent muscle atrophy or to assist in retraining motor control.

• Indication: Muscle atrophy and weakness, peripheral neuropathy, and neuromuscular retraining.
• Protocol: Higher pulse amplitude. Place the electrodes over your client’s muscle body.
• Description: Note your client’s muscle activation. Be aware of the parameters limited by tolerance.

Ultrasound

This video explains ultrasound, which is using sound to manipulate the body and help repair tissue.

Video is licensed under CC BY 4.0.

Ultrasound Video Transcript

Using Ultrasound Tips

The purpose of using ultrasound is to use sound to stimulate tissue repair. This procedure can be used with clients to decrease muscle stiffness, spasms, and pain; to increase cellular metabolism and capillary density; and to regenerate tissue and heal wounds.

• Indications: Assists with tissue healing. Most effective with high collagen-content tissues, such as ligaments, tendons, fascia, joint capsules, or scar tissue.
• Precautions
  • Avoid using on unhealed fracture sites.
  • Avoid using on early stages of tendon or ligament repair.
  • Avoid using with marked osteoporosis.
• Contraindications—DO NOT use with the following:
  • Plastic or metal implants.
  • Suspected deep vein thrombosis (DVT).
  • Bleeding or edema.
  • Reduced sensation.
  • Very old and very young.
  • Skin or lymphatic cancers.
  • Over a cardiac pacemaker.
  • In pregnancy or suspected pregnancy.
  • Over infection.
  • Epiphyses of growing bone.
  • Over heart, eyes, or testes.
  • Over carotid sinus or cervical ganglion.
  • Over the spinal column.
• Thermal—Continuous—Ultrasound
  • Physical effects
    • Heats tissue.
  • Physiological Effects
    • Increases collagen fibers’ extensibility.
    • Decreases muscle stiffness.
    • Reduces muscle spasm.
    • Alters nerve conduction velocity and diminishes pain perception.
    • Increases metabolism and blood flow.
    • Produces non-thermal effects.
• Non-Thermal—Pulsed—Ultrasound
  • Physical Principles
    • Produces stable cavitation.
    • Produces acoustic streaming.
  • Physiological Effects
    • Increases cellular metabolism.
    • Increases phagocytic activity of macrophages and attracts immune cells to tissue.
    • Increases protein synthesis.
    • Increases capillary density.
    • Regenerates tissue.
    • Heals wounds.
• Procedure
  • Use the below chart to calculate your ultrasound’s intensity and dosage.
    • Ultrasound Dosage Calculation Handout by Tim Watson at www.electrotherapy.org
  • Use conductive gel between the ultrasound’s head and your client’s skin.
  • Keep the ultrasound head in constant motion to prevent injuring or burning your your client.

Tim Watson, Ultrasound Dose Calculations 2017, p.7

Resources

• Electrical Stimulation – Its role in upper limb recovery post-stroke, Physiopedia
• Electrotherapy on the web by Tim Watson
• Transcutaneous Electrical Nerve Stimulation (TENS), Physiopedia

References

Bracciano, A. G. (2008). Physical agent modalities: Theory and application for the occupational therapist. Slack Incorporated.