Physical Agent,Mechanical,and Instrument-Assisted Modalities in Occupational Therapy Practice

Abstract

This AOTA Position Statement describes how physical agent, mechanical, and instrument-assisted modalities (PAMIMs) may be used by occupational therapy practitioners (i.e., occupational therapists and occupational therapy assistants) as part of a comprehensive plan of intervention designed to enhance engagement in occupation.

This AOTA Position Statement describes how physical agent, mechanical, and instrument-assisted modalities (PAMIMs) may be used by occupational therapy practitioners as part of a comprehensive plan of intervention designed to enhance engagement in occupation.

The American Occupational Therapy Association (AOTA) asserts that physical agent, mechanical, and instrument-assisted modalities (PAMIMs) may be used by occupational therapy practitioners (i.e., occupational therapists and occupational therapy assistants) as part of a comprehensive plan of intervention designed to enhance engagement in occupation (AOTA, 2020c). Occupational therapy practitioners possess the foundational knowledge of basic sciences, understanding of relevant theory and evidence, and clinical reasoning to recommend and safely apply PAMIMs to support the achievement of occupation-based client goals.

This Position Statement clarifies the context for the appropriate use of PAMIMs in occupation-based occupational therapy practice. As guided by the Occupational Therapy Practice Framework: Domain and Process (OTPF–4; AOTA, 2020c), the exclusive or stand-alone use of PAMIMs without linking them to a client-centered, occupation-based intervention plan and outcomes is not occupational therapy. Consistent with the 2018–2019 Choosing Wisely^® initiative, AOTA recommends that practitioners “don’t use [PAMIMs] without providing purposeful and occupation-based intervention activities” (Gillen et al., 2019). To ensure client-centered care, practitioners who choose to incorporate PAMIMs into their practice should evaluate the available evidence on the efficacy and effectiveness of each modality and its place in the treatment of a client’s condition.

Definitions

The term therapeutic modalities refers to the systematic application of various forms of energy or force to effect therapeutic change in the physiology of tissues. Physical agents, such as heat, cold, water, light, sound, and electricity, may be applied to the body to affect client factors, including the neurophysiologic, musculoskeletal, integumentary, circulatory, or metabolic functions of the body. Physical agents may be used to reduce or modulate pain, reduce inflammation, increase tissue extensibility and range of motion, promote circulation, decrease edema, facilitate healing, stimulate muscle activity, and facilitate occupational performance (Bracciano, 2022).

Physical agent modalities may be categorized on the basis of their properties:

Thermal modalities are those physical agents that provide a change in tissue temperature by either heating or cooling the tissue. Thermal modalities can also be categorized into superficial thermal agents and deep thermal agents on the basis of the depth of energy penetration into the underlying tissue or body structure they are targeting. Thermal agents (heat or cold) facilitate the transfer of energy between two systems through conduction, convection, or conversion.

Superficial thermal agents

Conduction: Heat or cold is transferred from an object to the body through direct contact with the modality. Examples include, but are not limited to, hot packs, cold packs, and paraffin (Vargas e Silva et al., 2019).

Convection: Heat or cold is transferred between two objects where one is moving or flowing around the body part. Examples include, but are not limited to, whirlpool or hydrotherapy, which can be done with hot or cold water, and Fluidotherapy^® or dry whirlpool, which uses dry heat to circulate dry cellulose medium around the distal extremity (Kumar et al., 2015).

Deep thermal agents

Conversion: Energy from low-frequency sound waves is converted into heat. A common example is therapeutic ultrasound, where the mechanical waves in sound energy are converted to heat using an ultrasound machine. Therapeutic ultrasound can be used to penetrate deeper tissue structures. Deep thermal agents include, but are not limited to, therapeutic ultrasound and phonophoresis (Morishita et al., 2014).

Electromagnetic modalities use electromagnetic waves, such as radio waves, microwaves, and light waves, to transport electrical and magnetic energy through space to effect changes in body structures (Post & Nolan, 2016).

Diathermy: Diathermy uses short-wave frequencies to affect healing tissue or higher frequencies that cause tissue heating.

Low-level laser (light) therapy (LLLT): Low-intensity, nonthermal (cold) lasers use light energy to cause a photochemical reaction in body tissue that can influence tissue repair, inflammation, and pain (Baktir et al., 2019).

Electrotherapy uses electrotherapeutic currents and waveforms to influence physiological effects on the client’s body structures (Bellew, 2016). Electrotherapy has many potential clinical uses and may act on tissues in the following ways:

To influence physiologic change in tissues to increase circulation, facilitate tissue healing, modify edema, and modulate pain. An example includes, but is not limited to, high-voltage galvanic stimulation for tissue and wound repair. A specific electrotherapeutic agent, iontophoresis, uses a direct electrical current to move ions of medication across the skin and into target tissues (Bracciano, 2022).

To facilitate neuromuscular or sensory activity to improve muscle strength, reeducate muscle function, or modulate pain response. Examples include, but are not limited to, neuromuscular electrical stimulation (NMES), functional electrical stimulation (FES), transcutaneous electrical nerve stimulation (TENS), and interferential current (IFC) (Bracciano, 2022).

The term mechanical modalities refers to the therapeutic use of mechanical devices to apply force, such as compression, distraction, vibration, or controlled mobilization, to modify biomechanical properties and functions of tissues. The effects of these mechanical modalities include increased circulation and lymphatic flow or increased tissue and joint mobility. Examples include, but are not limited to, mechanical traction, vasopneumatic devices, and continuous passive-motion machines.

The term instrument-assisted modalities (IMs) refers to the therapeutic use of an instrument or tool that is manually applied by a trained practitioner to target specific tissues, such as skin, fascia, and other connective tissues, or muscle. In contrast to a mechanical modality, the instrument or tool is skillfully and manually guided by a trained practitioner to effect change on the soft tissue. Although the true physiologic mechanisms of such interventions are not well known, IMs are theorized to achieve the following physiologic effects: mechanical deformation (e.g., stretch, movement of collagen fibers), localized inflammatory response (e.g., increased blood flow by means of vasodilation), and activation of the immune system (Altaş et al, 2022; Bitra & Sudhan, 2019; Jadhav & Gurudut, 2023). Through these mechanisms, the skilled practitioner seeks to achieve the ultimate therapeutic outcomes of pain reduction or analgesia, tissue healing, and improved functioning at the level of client factors (e.g., musculoskeletal functions, lymphatic flow) and occupational performance. Examples include, but are not limited to, thin filiform needles used in dry needling, stainless steel instruments applied to target tissue using a scraping technique, and suction instruments used in cupping therapy (Al-Bedah et al., 2019; Bush et al., 2020; Chys et al., 2023; Sánchez-Infante et al., 2021).

Occupational Therapy Practitioner Qualifications and Ethical Obligations

The Accreditation Council for Occupational Therapy Education (ACOTE®; 2018) requires that entry-level educational programs must prepare occupational therapists to demonstrate, and occupational therapy assistants to define, “the safe and effective application of superficial thermal agents, deep thermal agents, electrotherapeutic agents, and mechanical devices as a preparatory measure to improve occupational performance. This must include indications, contraindications, and precautions” for use (p. 31). Foundational knowledge, such as human anatomy, physiology, and biomechanics, is part of entry-level education for occupational therapists and occupational therapy assistants.

Occupational therapy practitioners should also refer to the Occupational Therapy Code of Ethics (AOTA, 2020a) for relevant principles and the Standards of Practice for Occupational Therapy (AOTA, 2021) to guide their practice. Many states where occupational therapy practitioners practice have additional regulatory requirements for demonstrating competence beyond entry-level education and for specific types of therapeutic modalities. Occupational therapy practitioners must be aware of, and comply with, these state-specific requirements, which may include, but are not limited to, continuing professional education, institution-specific procedures for ascertaining service competence, and supervised contact hours by a qualified practitioner in the respective state (AOTA, 2020a).

The efficacy of PAMIMs, including the use of new technology, is routinely updated, revised, and developed on the basis of the most currently available evidence. Practitioners are responsible for evaluating the evidence and for maintaining their awareness of new developments, as well as for maintaining their competency in the safe and effective application of these technologies.

Insurance coverage and billing policies for therapeutic modalities set forth by federal and state payers (e.g., Medicare, Veterans Affairs, state Medicaid programs), and commercial payers may vary widely. Practitioners are responsible for checking their payer policies and state practice acts to learn of any restrictions in coverage and usage. As part of their ethical responsibility, occupational therapy practitioners should also be mindful of the client’s ability to access services that include PAMIMs. In situations in which a practitioner has limited access to PAMIMs equipment or tools, they should apply clinical and professional reasoning skills to use low-tech substitutes to which the client has access and that have known therapeutic effects.

The Occupational Therapy Process

The OTPF–4 provides guidance to occupational therapy practitioners when evaluating the need for PAMIMs and incorporating their use as interventions to support occupations (AOTA, 2020c). Throughout the occupational therapy process, an occupational therapist and an occupational therapy assistant may collaborate and play distinct roles.

Evaluation

During the evaluation process, occupational therapists establish an occupational profile to identify client priorities, gain an appreciation of the client’s health and well-being, and understand the contextual supports of and barriers to performance. Therapists further analyze client performance in chosen occupations to identify the specific focus of the intervention, including impairments in client factors, deficits in performance skills, and overall limitations in occupational performance. The presence of impairments in body functions and body structures as barriers to occupational performance may facilitate clinical reasoning in choosing appropriate PAMIMs. Therapists consider the evidence, pragmatics, and benefits of PAMIMs as an integral component of the occupation-based intervention plan. Occupational therapy assistants may contribute to the evaluative process, especially in establishing the client’s occupational profile, once competency in the administration of standardized and nonstandardized assessments has been achieved (ACOTE, 2018; AOTA, 2021).

Intervention

Occupational therapists may collaborate on the implementation of an intervention plan that involves the use of PAMIMs with occupational therapy assistants who demonstrate service competence (AOTA, 2020b). The occupational therapist has the overall responsibility for providing supervision of the occupational therapy assistant and their safe use of PAMIMs with clients. The occupational therapy assistant is also responsible for understanding how the use of PAMIMs supports the client’s occupational therapy goals (AOTA, 2020b). Both occupational therapists and occupational therapy assistants should monitor and appropriately document the outcome of interventions. Using PAMIMs as part of a comprehensive intervention plan can facilitate active engagement and participation in occupational tasks and improve occupational performance (see the Appendix for examples).

As part of the intervention plan, the therapeutic use of PAMIMs may be categorized as follows:

Interventions to support occupations. Occupational therapy practitioners administer PAMIMs to address barriers to body functions and structures before engaging in occupation. For example, a practitioner may apply thermal modalities to a client’s hands and wrists to increase tissue extensibility and alleviate pain before engaging in cooking activities.

Concurrent to therapeutic occupation or purposeful activities. To improve performance, occupational therapy practitioners may administer PAMIMs to reduce the impact of impairment on body functions and structures while the client is engaged in occupation. For example, a practitioner may apply FES to the client’s affected wrist extensors and flexors during a morning grooming routine to facilitate grasp and release.

As a necessary component of a person’s occupational routine. Occupational therapy practitioners may recommend and train a client to self-administer PAMIMs as part of their health management and maintenance. For example, a practitioner may teach a client how to perform manual lymph drainage massage, use an intermittent pneumatic compression device, and properly apply compression garments to abate the effects of lymphedema on occupational performance.

Outcomes

Outcomes are related to intervention implementation and are established during the evaluation process (AOTA, 2020c). An occupational therapy practitioner may choose to use PAMIMs as an intervention if it is thought to support occupational engagement. In collaboration with the client, occupational therapy practitioners determine the target outcomes and monitor the client’s progress over time and the progress made as the result of PAMIMs and associated interventions. Under the supervision of the occupational therapist, an occupational therapy assistant may administer an outcome measure, which is then analyzed to determine the need for continuation or discontinuation of services or modification of the intervention plan.

Conclusion

The use of PAMIMs may be an integral part of an occupational therapy intervention that supports or enhances a client’s occupational performance, health and wellness, participation, and quality of life (AOTA, 2020c). Although entry-level preparation for occupational therapists and occupational therapy assistants indicates knowledge and practice preparation in the use of select therapeutic modalities (ACOTE, 2018), occupational therapy practitioners should strive to maintain their service competency in these modalities within the parameters of practice established by their state regulatory boards, payers, and institutional policies.

Authors

Salvador Bondoc, OTD, OTR/L, BCPR, CHT, FAOTA

Ann Marie Feretti, EdD, OTR/L, CHT

For the Commission on Practice

Meredith Gronski, OTD, OTR/L, CLA, FAOTA, Chairperson

Adopted by the Representative Assembly Coordinating Council (RACC) for the Representative Assembly, April 2024.

Note. This revision replaces the 2018 document “Physical Agents and Mechanical Modalities,” previously published and copyrighted in 2018 by the American Occupational Therapy Association in the American Journal of Occupational Therapy, 72(Suppl. 2), 7212410055. https://doi.org/10.5014/ajot.2018.72S220

Copyright © 2024 by the American Occupational Therapy Association, Inc.

Citation. American Occupational Therapy Association. (2024). Physical agent, mechanical, and instrument-assisted modalities in occupational therapy practice. American Journal of Occupational Therapy, 78(Suppl. 1), 7810410120. https://doi.org/10.5014/ajot.2024.78S103.