HILT Dose Optimization for Knee Osteoarthritis Pain

Official title

Optimal High-Intensity Laser Therapy (HILT) Parameters for Pain and Function in Patients With Moderate Knee Osteoarthritis: A Randomized Controlled Trial

Overview

This study aims to find the best settings (dose) for High-Intensity Laser Therapy (HILT) to reduce pain and improve function in people with moderate knee osteoarthritis. Participants will be randomly assigned to receive one of three different doses of HILT (low, medium, or high) or a sham (placebo) laser treatment, three times a week for four weeks. The main outcomes measured will be changes in knee pain (using a pain scale) and knee function (using a questionnaire) from the beginning to the end of the 4-week treatment period.

Interventions

• Device Low-Dose High-Intensity Laser Therapy (10 J/cm²)
  Application of HILT using an Nd:YAG laser (BTL-6000, 1064 nm). Delivered via continuous scanning technique (1 cm distance) to 5 zones (25 cm² each) covering anterior, medial, and lateral knee aspects. Target dose: 10 J/cm² per zone. Session frequency: 3x/week for 4 weeks (12 total). Session duration: 15-20 min. Administered by trained PTs in outpatient rehab. Skin temperature monitored.
• Device Medium-Dose High-Intensity Laser Therapy (15 J/cm²)
  Application of HILT using an Nd:YAG laser (BTL-6000, 1064 nm). Delivered via continuous scanning technique (1 cm distance) to 5 zones (25 cm² each) covering anterior, medial, and lateral knee aspects. Target dose: 15 J/cm² per zone. Session frequency: 3x/week for 4 weeks (12 total). Session duration: 15-20 min. Administered by trained PTs in outpatient rehab. Skin temperature monitored.
• Device High-Dose High-Intensity Laser Therapy (20 J/cm²)
  Application of HILT using an Nd:YAG laser (BTL-6000, 1064 nm). Delivered via continuous scanning technique (1 cm distance) to 5 zones (25 cm² each) covering anterior, medial, and lateral knee aspects. Target dose: 20 J/cm² per zone. Session frequency: 3x/week for 4 weeks (12 total). Session duration: 15-20 min. Administered by trained PTs in outpatient rehab. Skin temperature monitored.
• Device Sham High-Intensity Laser Therapy
  Sham procedure mimicking active HILT using the same Nd:YAG laser device (BTL-6000). Same setup, patient positioning, scanning technique over identical zones, and session duration/frequency (3x/week, 4 weeks, 15-20 min). Device powered on with visual/auditory cues active, but no laser energy emitted. Administered by trained PTs in outpatient rehab. Skin temperature monitored.

Primary outcome measures

• Change in Knee Pain Intensity [Time frame: Baseline (T0), Mid-treatment (T1 - after 6 sessions), Post-treatment (T2 - after 12 sessions), 3-month Follow-up (T3)]
• Change in Knee Osteoarthritis Symptoms and Function [Time frame: Baseline (T0), Mid-treatment (T1), Post-treatment (T2), 3-month Follow-up (T3)]

Secondary outcome measures (3)

• Change in Knee Range of Motion (Flexion and Extension) [Time frame: Baseline (T0), Post-treatment (T2), 3-month Follow-up (T3)]
• Change in Functional Mobility [Time frame: Baseline (T0), Post-treatment (T2), 3-month Follow-up (T3)]
• Incidence of Adverse Events [Time frame: Throughout study participation (up to 3-month follow-up)]

Eligibility criteria

Inclusion criteria

Age between 45 and 75 years, inclusive. Clinical diagnosis of knee osteoarthritis according to American College of Rheumatology (ACR) criteria (knee pain plus at least 3 of 6: age >50, morning stiffness <30 min, crepitus, bony tenderness, bony enlargement, no palpable warmth).

Radiographic evidence of knee osteoarthritis corresponding to Kellgren-Lawrence grade II or III in the target knee.

Average knee pain intensity ≥ 4 on a 10-cm Visual Analogue Scale (VAS) during weight-bearing activities in the past week.

Willingness and ability to attend 3 sessions per week for 4 weeks and attend all assessment sessions.

Exclusion criteria

Previous surgery on the index knee (including arthroscopy within the last year or joint replacement).

Diagnosis of inflammatory arthritis (e.g., rheumatoid arthritis, psoriatic arthritis, gout).

Intra-articular corticosteroid or hyaluronic acid injection in the index knee within the last 3 months.

Clinically significant comorbidities that could interfere with participation or assessment (e.g., severe uncontrolled cardiovascular disease, severe pulmonary disease, significant neurological deficits affecting the lower limb).

Presence of skin conditions (e.g., infection, open wounds, eczema, photosensitivity disorders) in the area designated for laser treatment.

Current use of anticoagulant medication (e.g., warfarin, DOACs) due to potential risk, unless stable and cleared by physician. (Consider if this is truly necessary based on HILT mechanism).

History of cancer in the treatment area or active malignancy elsewhere. Known photosensitivity or use of photosensitizing medications. Pregnancy, planning pregnancy, or breastfeeding. Participation in another interventional clinical trial within the last 30 days. Inability to understand or communicate in the study language.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Triple blind

Primary purpose

Treatment

Study locations

Egypt · 1 center

• Faculty of Physical Therapy, Al Hayah University — Cairo

Identifiers

NCT: NCT06916676 · HILT-KOA-DOSE

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗