"Bimodal vs Unimodal High-Intensity Pulsed Electromagnetic Field Therapy in Older Adults With Knee Osteoarthritis"

NCT ID: NCT07198750

Last Updated: 2025-09-30

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 64 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-09-15
• Study Completion Date: 2026-04-15

Brief Summary

This randomized, double-blind clinical trial aims to evaluate the effect of high-intensity pulsed electromagnetic field therapy (HI-PEMF) applied either exclusively on the knee joint or bimodally on the knee and quadriceps, in older adults with knee osteoarthritis. Both groups will also receive a structured home-based exercise program. The primary outcome is pain reduction, and secondary outcomes include functional performance.

Detailed Description

Knee osteoarthritis (OA) is a highly prevalent and disabling condition in older adults. It often coexists with quadriceps muscle weakness, sarcopenia, and frailty, all of which contribute to pain, functional decline, and loss of independence. Pulsed electromagnetic field therapy (PEMF) has emerged as a non-invasive alternative for pain relief in OA, with growing interest in its application at both articular and muscular levels.

High-intensity pulsed electromagnetic field (HI-PEMF) therapy-also known as the super inductive system-generates magnetic fields up to 2.5 Tesla, capable of stimulating both joint structures and skeletal muscle via deep tissue electric induction. HI-PEMF has shown promising results for pain reduction, anti-inflammatory modulation, and muscle bioactivation, particularly when applied over the quadriceps.

This randomized, double-blind, parallel-assignment clinical trial aims to compare the effects of two HI-PEMF treatment modalities in older adults with moderate to severe knee OA (Kellgren-Lawrence grade II-IV):

• Group A: HI-PEMF applied exclusively over the symptomatic knee.
• Group 2: HI-PEMF applied both over the knee and the quadriceps (bimodal). Both groups will also perform a standardized home-based strengthening and mobility exercise program.

A total of 64 participants (32 per group) will receive 9 sessions of HI-PEMF (2 per week for 5 weeks), using the BTL-6000 Super Inductive System. Outcomes will be assessed at baseline and post-intervention. The primary outcome is change in pain intensity using the Numeric Analog Scale (NAS). Secondary outcomes include functional tests (Timed Up and Go and 5-times Sit-to-Stand), and paracetamol use. Exploratory subgroup analyses will assess associations with frailty status (FRAIL), probable sarcopenia (SARC-F), and radiological OA grade.

This study seeks to generate evidence on the potential synergistic benefits of combining articular and muscular HI-PEMF therapy in geriatric rehabilitation. It is designed for implementation in a public hospital setting in Mexico, with minimal risk and high feasibility. All procedures follow ethical guidelines and have received institutional review board approval.

Conditions

Knee Osteoarthritis; Osteoarthritis; Osteo Arthritis of the Knee; Gonarthrosis

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Group A - Unimodal HI-PEMF

Participants in Group A will receive high-intensity pulsed electromagnetic field therapy (HI-PEMF) applied exclusively to the symptomatic knee (femorotibial joint) for 10 minutes per session, twice a week over 5 weeks, completing a total of 9 sessions. The intervention will use the "Chronic Pain" protocol of the BTL-6000 Super Inductive System. A standardized home-based exercise program will be provided to all participants.

Group Type: EXPERIMENTAL

HI-PEMF - Knee (Chronic Pain Protocol)

Intervention Type: DEVICE

High-intensity pulsed electromagnetic field (HI-PEMF) therapy applied to the symptomatic knee using the "Chronic Pain" protocol of the BTL-6000 Super Inductive System, 10-minute duration per session, applied twice per week over 5 weeks (total of 9 sessions). The applicator is positioned 2-3 cm above the patella, without skin contact, with the patient seated or in supine position.

Home-Based Exercise Program

Intervention Type: BEHAVIORAL

Standardized home-based exercise program prescribed to both groups. It includes five exercises: isometric quadriceps contractions, straight leg raises, seated knee extensions, sit-to-stand from chair, and stationary marching. Participants are instructed to perform the exercises three times per week during the 5-week intervention. Printed instructions and a video guide are provided. Adherence is reinforced via weekly follow-up.

Group B - Bimodal HI-PEMF

Participants in Group B will receive high-intensity pulsed electromagnetic field therapy (HI-PEMF) applied to both the symptomatic knee (femorotibial joint) and the quadriceps muscle (rectus femoris), with 10 minutes per site, twice a week over 5 weeks, completing a total of 9 sessions. The knee application will follow the "Chronic Pain" protocol, and the quadriceps application will follow the "Muscle Strengthening" protocol, both using the BTL-6000 Super Inductive System. A standardized home-based exercise program will be provided to all participants.

Group Type: EXPERIMENTAL

HI-PEMF - Quadriceps (Muscle Strengthening Protocol)

Intervention Type: DEVICE

HI-PEMF therapy will be applied to both the symptomatic knee and the quadriceps muscle (rectus femoris). The knee application will follow the same procedure as in Group A, using the "Chronic Pain" protocol of the BTL-6000 Super Inductive System. In addition, the quadriceps will be treated using the "Muscle Strengthening" protocol. Each site will receive 10 minutes of therapy per session, twice per week over 5 weeks (total of 9 sessions). The applicator for the quadriceps will be positioned perpendicular to the muscle belly, without skin contact, with the patient lying supine and a cushion under the knee for slight flexion.

Home-Based Exercise Program

Intervention Type: BEHAVIORAL

Standardized home-based exercise program prescribed to both groups. It includes five exercises: isometric quadriceps contractions, straight leg raises, seated knee extensions, sit-to-stand from chair, and stationary marching. Participants are instructed to perform the exercises three times per week during the 5-week intervention. Printed instructions and a video guide are provided. Adherence is reinforced via weekly follow-up.

Interventions

HI-PEMF - Knee (Chronic Pain Protocol)

High-intensity pulsed electromagnetic field (HI-PEMF) therapy applied to the symptomatic knee using the "Chronic Pain" protocol of the BTL-6000 Super Inductive System, 10-minute duration per session, applied twice per week over 5 weeks (total of 9 sessions). The applicator is positioned 2-3 cm above the patella, without skin contact, with the patient seated or in supine position.

Intervention Type: DEVICE

HI-PEMF - Quadriceps (Muscle Strengthening Protocol)

HI-PEMF therapy will be applied to both the symptomatic knee and the quadriceps muscle (rectus femoris). The knee application will follow the same procedure as in Group A, using the "Chronic Pain" protocol of the BTL-6000 Super Inductive System. In addition, the quadriceps will be treated using the "Muscle Strengthening" protocol. Each site will receive 10 minutes of therapy per session, twice per week over 5 weeks (total of 9 sessions). The applicator for the quadriceps will be positioned perpendicular to the muscle belly, without skin contact, with the patient lying supine and a cushion under the knee for slight flexion.

Intervention Type: DEVICE

Home-Based Exercise Program

Standardized home-based exercise program prescribed to both groups. It includes five exercises: isometric quadriceps contractions, straight leg raises, seated knee extensions, sit-to-stand from chair, and stationary marching. Participants are instructed to perform the exercises three times per week during the 5-week intervention. Printed instructions and a video guide are provided. Adherence is reinforced via weekly follow-up.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• Age ≥ 60
• Clinical and radiological diagnosis of knee OA grade I-IV
• Pain ≥ 3 on Numeric Analog Scale for >6 months
• Can walk (with/without aid)
• Cognitive ability to follow instructions
• Signed informed consent

Exclusion Criteria

• Prior total knee arthroplasty (unilateral or bilateral)
• Neurological disorders affecting motor function or cognition (e.g., Parkinson's disease, stroke, moderate to severe dementia)
• Active inflammatory rheumatic diseases (e.g., rheumatoid arthritis, lupus)
• Presence of pacemakers, implantable defibrillators, or metallic implants near the treatment area
• Current use of other physical therapy modalities for pain (e.g., electrotherapy, ultrasound, TENS) outside the study protocol
• Participation in another clinical trial within the past 3 months
• Current use of NSAIDs or systemic/local corticosteroids (including intra-articular injections)
• Open wounds or active infections at the treatment site
• Decompensated cardiac conditions or medical contraindication to exercise
• Vestibular disorders that affect balance and interfere with functional assessments
• Uncorrected visual impairment interfering with gait or balance (visual acuity worse than 20/60 in the better eye, assessed by Snellen chart)

Withdrawal Criteria:

• Participants who complete fewer than 7 out of the 9 planned intervention sessions (i.e., less than 80% adherence)
• Occurrence of serious adverse events related to the intervention that contraindicate continuation
• Repeated non-compliance with the home exercise program, documented in at least two consecutive weekly follow-up reports
• Voluntary withdrawal of consent at any time during the study

• Minimum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Hospital Civil de Guadalajara

OTHER

Sponsor Role: lead

Responsible Party

Ana Lilia Villagrana Rodríguez

Physician Specialist, Department of Physical and Rehabilitation Medicine

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Hospital Civil de Guadalajara "Fray Antonio Alcalde"

Guadalajara, Jalisco, Mexico

Site Status: RECRUITING

Countries

Mexico

Facility Contacts

Ana L Villagrana Rodríguez, MD

Role: primary

alvillagrana@hcg.gob.mx

+523324261190

Ileana Díaz Solís, MD

Role: backup

inforehabilitacion.ids@gmail.com

+523328184251

References

Iannitti T, Fistetto G, Esposito A, Rottigni V, Palmieri B. Pulsed electromagnetic field therapy for management of osteoarthritis-related pain, stiffness and physical function: clinical experience in the elderly. Clin Interv Aging. 2013;8:1289-93. doi: 10.2147/CIA.S35926. Epub 2013 Sep 26.

Reference Type: BACKGROUND

PMID: 24106421 (View on PubMed)

Ong MT, Man GC, Lau LC, He X, Qiu J, Wang Q, Chow MC, Choi BC, Yu M, Yung PS. Effect of pulsed electromagnetic field as an intervention for patients with quadriceps weakness after anterior cruciate ligament reconstruction: a double-blinded, randomized-controlled trial. Trials. 2022 Sep 12;23(1):771. doi: 10.1186/s13063-022-06674-2.

Reference Type: BACKGROUND

PMID: 36096886 (View on PubMed)

Bagnato GL, Miceli G, Marino N, Sciortino D, Bagnato GF. Pulsed electromagnetic fields in knee osteoarthritis: a double blind, placebo-controlled, randomized clinical trial. Rheumatology (Oxford). 2016 Apr;55(4):755-62. doi: 10.1093/rheumatology/kev426. Epub 2015 Dec 24.

Reference Type: BACKGROUND

PMID: 26705327 (View on PubMed)

Other Identifiers

CEI-151-25

Identifier Type: -

Identifier Source: org_study_id