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Intermittent Hypoxia-Hyperoxia Combined With Physical Therapy for Knee Osteoarthritis

Effectiveness of Combining Intermittent Hypoxia-Hyperoxia and Conventional Physical Therapy for Patients With Knee Osteoarthritis: A Randomized Controlled Trial

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06965946
Enrollment
60
Registered
2025-05-11
Start date
2025-05-15
Completion date
2026-06-22
Last updated
2026-06-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Osteo Arthritis Knee

Keywords

Knee Osteoarthritis, Intermittent Hypoxia, Hypoxic-Hyperoxic Therapy, Rehabilitation, Functional Mobility

Brief summary

This randomized controlled trial aims to evaluate the effectiveness of combining intermittent hypoxia-hyperoxia therapy (IHHT) with conventional physical therapy in improving pain, function, gait, balance, and general health among patients with knee osteoarthritis. The study will be conducted at the Physical Therapy Department of Rehman Medical Institute, Peshawar, Pakistan, over a period of one year.

Detailed description

Osteoarthritis (OA) is a prevalent chronic condition that leads to joint pain, stiffness, and impaired mobility, particularly among middle-aged and elderly populations. In Pakistan, knee OA is common and significantly impacts quality of life. Existing treatments are largely symptomatic and often insufficient, especially in resource-constrained settings. Intermittent hypoxia-hyperoxia training (IHHT), involving alternating periods of low (13-15%) and high (40%) oxygen concentrations, has shown promise in improving physical and psychological outcomes in musculoskeletal disorders. However, evidence regarding its efficacy in knee OA is scarce, especially in low- and middle-income countries. This trial seeks to explore whether the combination of IHHT and conventional physical therapy leads to superior improvements in clinical outcomes compared to conventional therapy alone. Participants will undergo 12 treatment sessions over 4 weeks. The primary outcome measures include pain (NPRS), function (KOOS), balance (Timed Up and Go Test), gait (Functional Gait Assessment), and inflammatory markers (CRP). The feasibility, safety, and effectiveness of this novel intervention will also be evaluated. The study design includes assessor and participant blinding and uses rigorous methods including pre- and post-intervention assessments and statistical analysis with SPSS. Findings from this study may inform future guidelines for non-pharmacological, low-cost interventions for knee OA rehabilitation in similar contexts.

Interventions

PROCEDUREIntermittent Hypoxia-Hyperoxia Therapy (IHHT)

Participants receive 4 cycles per session of 5 minutes of hypoxia (13-15% O₂) followed by 2 minutes of hyperoxia (40% O₂) using a hypoxia generator (Olive OLV 10H). Sessions are delivered before each conventional physical therapy session, 3 times per week for 4 weeks (total 12 sessions). Participants are monitored for heart rate, blood pressure, and oxygen saturation throughout the intervention.

PROCEDUREConventional Physical Therapy

Participants receive individualized conventional physical therapy for knee osteoarthritis based on current clinical practices in tertiary hospitals of Peshawar. Therapy is delivered 3 times per week for 4 weeks (total 12 sessions) and includes strength training, mobility exercises, and patient education.

PROCEDURENormoxic Air Placebo

Participants in the control group inhale normoxic air (19.8% O₂) using the same Olive OLV 10H hypoxia generator to maintain blinding. Each session consists of 4 cycles of 5 minutes of normoxia followed by 2 minutes of normoxia, simulating the timing of hypoxia-hyperoxia therapy. Sessions are administered prior to conventional physical therapy, 3 times per week for 4 weeks (total 12 sessions). Patients are monitored for vital signs throughout.

Sponsors

Khyber Medical University Peshawar
Lead SponsorOTHER
Rehman Medical Institute - RMI
CollaboratorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)

Masking description

This study is double blind. Both participants and outcome assessors are blinded to group allocation. Randomization is conducted via OpenEpi, and intervention/control sessions are administered with controlled oxygen levels, but the appearance and procedures are standardized to maintain blinding.

Intervention model description

This is a two-arm parallel-group randomized controlled trial. Participants will be randomly assigned to either the experimental group receiving intermittent hypoxia-hyperoxia therapy along with conventional physical therapy or to the control group receiving conventional physical therapy with normoxic air. Both groups will receive 12 treatment sessions over four weeks.

Eligibility

Sex/Gender
ALL
Age
45 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Participants aged 45 and above. * Participants (both male and female) with knee pain for 3 months or more with any three of the following six items: age of 50 years or more, crepitations, enlarged bone, no palpable warmth, morning stiffness for less than 30 minutes, and bony tenderness. * Patients who can walk and have a minimum score of 4 on the Numeric Pain Rating Scale. * Participants who have intact cognition with a score of 24 and above on Mini Mini- Mental State examination. * Participants able to walk independently for at least 45 meters in the 6-minute walk test. * Participants having a recent X-ray (done within the past 3 months).

Exclusion criteria

* Patients with hip or knee arthroplasty. * Participants with above or below knee surgery or radiating pain to the lower limb. * Patients with history of epilepsy, pregnancy * Diagnosed neurological condition that affects lower-limb strength or walk (e.g., stroke/ basal ganglia dysfunction/ trauma) * Patients who refused to participate in the study or to be randomly allocated. * Patients receiving steroids or any medicine other than that prescribed by the screening orthopaedic surgeon.

Design outcomes

Primary

MeasureTime frameDescription
Pain ReductionBaseline and 4 weeks (12 sessions of therapy)Measured on the Numeric Pain Rating Scale (NPRS), which has levels ranging from 0 to 10 in severity. 0 indicates no pain, and 10 indicates severe pain. The scale is divided into 3 categories. 1-3 indicates mild pain, 4-6 indicates moderate pain, and 7-10 indicates severe pain.
Functional Status - KOOS Activities of Daily Living SubscaleBaseline and 4 weeksThe Knee Injury and Osteoarthritis Outcome Score (KOOS) will be used to assess pain, recreation and quality of life, symptoms and stiffness, ADL and functional sports. The scores of each category will be calculated and converted to percentages (100%). 0-39% will indicate severe condition, 40- 59% will indicate moderate condition, 60-79% will indicate mild condition, and 80-100% will indicate no dysfunction.
Inflammatory Marker - C-Reactive Protein (CRP)Baseline and 4 weeksChange in serum CRP levels measured through a blood sample as a biomarker of osteoarthritis-related inflammation. CRP levels will be taken on a continuous scale.
Balance - Timed Up and Go Test (TUG)Baseline and 4 weeksTime taken (in seconds) to rise from a chair, walk 3 meters, turn, walk back, and sit down using a stop watch. A time of \< or equal to 10 seconds will be considered normal, 11-20 seconds indicates good mobility with functional indipendence. \> or equal to 20 seconds indicates that person needs assistance outside, 30 seconds or more indicates that person is prone to fall. MCID for time up and Go test is 2.1 seconds.

Secondary

MeasureTime frameDescription
Gait Performance - Functional Gait Assessment (FGA) ScoreBaseline and 4 weeksEvaluation of gait performance and stability using the FGA scale. Normal (score of 3) performances will be walking a distance of 6 meters in less than 5.5 seconds with no assistive device and no evidence of imbalance, a normal gait pattern, and not deviating more than 6 inches out of 12 12-inch walkway width. Mild impairment (score of 2) will be recorded when a person walks 6 meters with the use of an assistive device at a slower speed and mild gait deviation (15.24-25.4 cm) outside 12 12-inch walkway. Participants will be scored 1, moderate impairment, if they walk with a slower speed, abnormal gait pattern, evidence of imbalance, deviates 10-15 inches outside 12 12-inch walkway width. Participants will be said to have severe impairment, score of 0, if they can not walk 6 meters (20 feet) without assistance, severe gait deviations or imbalance, deviates greater than 15 inches outside 12 12-inch walkway width or will not attempt the task.
Functional mobility - 6-Minute Walk Test (6MWT)Baseline and 4 weeksDistance (in meters) covered during a 6-minute walk test to assess aerobic capacity and endurance. Normal score ranges from 400-700 meters. The participants will be asked to walk for 6 minutes, and the distance covered will be noted. The MCID for the 6-minute walk test is 45 meters.

Countries

Pakistan

Contacts

PRINCIPAL_INVESTIGATORDr Rida Shabbir, PhD

Institute of Physical Medicine and Rehabilitation, Khyber Medical University Peshawar

PRINCIPAL_INVESTIGATORDr Haider Darain, PhD

Institute of Physical Medicine and Rehabilitation, Khyber Medical University Peshawar

PRINCIPAL_INVESTIGATORDr Aatik Arsh, PhD

Institute of Physical Medicine and Rehabilitation, Khyber Medical University Peshawar

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jun 26, 2026