Eccentric vs Low-Load Blood Flow Restriction Training in Knee Osteoarthritis in Knee Osteoarthritis (the)

Comparison of Eccentric and Low-Load Blood Flow Restriction Training on Neuromuscular Adaptations in Knee Osteoarthritis

The aim of this randomized controlled trial is to find the effects of eccentric and low-load blood flow restriction training on neuromuscular adaptations, muscle strength, functional performance, and disability in patients with knee osteoarthritis

Study Overview

• Status: Recruiting
• Conditions: Knee Arthritis, Osteoarthritis
• Intervention / Treatment: Other: Eccentric Gastrocnemius Strengthening Exercises; Other: Low-Load Blood Flow Restriction Training

Detailed Description

Osteoarthritis (OA) is a chronic disease affecting the joint and its tissues, primarily leading to progressive damage to articular cartilage and, subsequently, to the subchondral bone and surrounding synovial structures. This chronic degenerative disease affects approximately one-third of adults, and its prevalence increasing with advancing age. The knee is one of the most common joints affected by the OA. Systematic reviews indicate a global prevalence of knee osteoarthritis (KOA) is 22.9% among individuals aged 40 and older, affecting an estimated 654.1 million people worldwide, with variations across countries and increasing with age.

Knee osteoarthritis (KOA) is a multi etiological, chronic disabling disease that affects the entire knee joint, which is the most common site of involvement in OA. KOA patients mostly suffer from progressive stiffness and knee pain. Gradually, they have some difficulties in performing daily activities, such as walking, squatting, and climbing and doing housework, as the disease progresses. Ultimately, pain and disability associated with the disease lead to a loss of functional independence and a profound reduction in quality-of- life. Impairments that are caused by KOA include knee pain, limited ROM of the knee, muscle weakness and knee instability.

The gastrocnemius muscle plays a crucial role in knee joint stability and ankle-knee biomechanics through its biarticular function, contributing to both knee flexion and ankle plantarflexion. During the stance phase of gait, the gastrocnemius co-activates with the tibialis anterior and quadriceps muscles, providing dynamic stability, reducing medial knee laxity, and assisting in forward propulsion.

The impaired neuromuscular recruitment of the gastrocnemius may result in reduced push-off strength, prolonged ground contact time, and diminished functional performance, ultimately contributing to functional limitations in patients with knee osteoarthritis. However, surface electromyography (sEMG) enables the assessment of gastrocnemius motor unit recruitment and fatigue characteristics, providing objective insight into neuromuscular adaptations before and after targeted interventions.

OA of the knee is characterized by changes in gait kinematics. In patients with knee OA, deficits in gastrocnemius strength and endurance can exacerbate difficulties in activities such as stair climbing, walking, and balance maintenance. Eccentric and low-load blood flow restriction (LL-BFR) training protocols have been proposed to optimize gastrocnemius activation, enhance muscle strength, and improve functional performance, offering clinically relevant rehabilitation strategies for enhancing lower limb function and reducing disability in knee osteoarthritis.

This study is to find the effects of eccentric and low-load blood flow restriction training on neuromuscular adaptations, muscle strength, functional performance, and disability in individuals affected by the knee OA.

• Study Type: Interventional
• Enrollment (Estimated): 48
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: KINZA ANWAR, MS-OMPT; Phone Number: +92-3239735427; Email: kinza.anwar@riphah.edu.pk

Study Locations

• Pakistan
  • Punjab Province
    • Rawalpindi, Punjab Province, Pakistan, 46000
      • Recruiting
      • Railway General Hospital, Rawalpindi
      • Contact: KINZA ANWAR, MS-OMPT; Phone Number: +92-3239735427; Email: kinza.anwar@riphah.edu.pk
      • Contact: SEHRISH MALIK, MS-OMPT*
      • Sub-Investigator: SEHRISH MALIK, MS-OMPT*

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age group 40-70
• Both genders male and female
• Clinical diagnosis of knee OA (Kellgren-Lawrence grade 1-3) of the most symptomatic knee.
• Pain stable enough to permit exercise on Numeric Pain Rating Scale 3/10.
• Participants must demonstrate a gastrocnemius muscle strength of grade ≥3 on the Manual Muscle Testing (MMT) scale (0-5), assessed using the standard standing heel-rise position.
• Participants must be able to ambulate independently and participate in supervised exercise.

Exclusion Criteria:

• • Presence of a prosthetic knee in the affected limb.

  • Inflammatory arthritis (e.g., rheumatoid arthritis) or active flare-up of OA.
  • Cardiovascular disease contraindicating exercise (e.g., unstable angina, recent MI, uncontrolled hypertension ≥160/100 mmHg).
  • Pulmonary disease that limits safe participation (e.g., severe COPD, recent exacerbation).
  • History of deep vein thrombosis (DVT), peripheral vascular disease, or bleeding/clotting disorders.
  • Current anticoagulant therapy that increases bleeding risk (unless cleared by physician).
  • Any pathology causing significant muscle weakness (e.g., neuromuscular disorders, severe neuropathy).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Eccentric Training; Eccentric Gastrocnemius Strengthening Exercises	Other: Eccentric Gastrocnemius Strengthening Exercises; Eccentric Gastrocnemius Strengthening Exercises .1. Eccentric Heel Drop 2. leg press calf lowering 3. Eccentric Stair Descent (Frequency: 3 sets 10 reps in session 1-2). 1. Eccentric Heel Drop 2. leg press calf lowering 3. Eccentric Stair Descent (Frequency: 5 sets 15 reps in session 3-4). Total duration is 3 sessions per week for 4 consecutive weeks.
Experimental: Low-Load Blood Flow Restriction Training	Other: Low-Load Blood Flow Restriction Training; Low-load blood flow restriction training including 1-Low-intensity gastrocnemius strengthening with BFR cuff 2-Controlled exercise with intermittent vascular occlusion (inflated 50-70% for 4 weeks, 3 rep. 1. Eccentric Heel Drop 2. leg press calf lowering 3. Eccentric Stair Descent (Frequency: 3 sets 10 reps in session 1-2). 1. Eccentric Heel Drop 2. leg press calf lowering 3. Eccentric Stair Descent (Frequency: 5 sets 12 reps in session 3-4). Total duration is 3 sessions per week for 4 consecutive weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Surface Electromyography	The Electromyography (EMG) is an objective assessment tool used to measure the electrical activity of muscles during contraction. Motor unit recruitment will be analyzed through the amplitude of EMG signals (root mean square, RMS), reflecting the number and synchronization of active motor units during contraction. Fatigue characteristics will be assessed using changes in EMG frequency parameters (mean or median frequency), indicating alterations in muscle fiber conduction velocity and fatigue onset that will be assessed pre and post sessions.	Baseline and 4th week

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)	The WOMAC is a widely used, validated questionnaire assessing pain, stiffness, and physical function in patients with knee osteoarthritis. It consists of 24 items divided into three subscales: Pain (5 items), Stiffness (2 items), and Physical Function (17 items).	4 weeks
Timed Up and Go (TUG)	The Timed Up and Go (TUG) test assesses mobility and fall risk by timing how quickly a person can stand up from a standard armchair, walk 3 meters (10 feet) at a normal pace, turn around, walk back, and sit down again. Individuals can use their routine walking aids, but receive no physical help during the test; completing the maneuver in under 10 seconds indicates normal independence, whereas taking 30 seconds or longer points to an elevated risk of falling.	4 weeks
Heel Raise Endurance Test	The Heel Raise Endurance Test measures the number of consecutive heel raises a participant can perform (or the time sustained) while standing, usually at a controlled pace until fatigue. It assesses calf muscle endurance, ankle plantar-flexor strength, and functional lower-limb performance, relevant for gait and mobility assessment. The duration for which the position is maintained is recorded.	4 weeks

Collaborators and Investigators

• Sponsor: Riphah International University
• Investigators: Principal Investigator: KINZA ANWAR, MS-OMPT, Riphah International University

Study record dates

Study Major Dates

• Study Start (Actual): July 21, 2026
• Primary Completion (Estimated): December 21, 2026
• Study Completion (Estimated): December 28, 2026

Study Registration Dates

• First Submitted: July 24, 2026
• First Submitted That Met QC Criteria: July 24, 2026
• First Posted (Actual): July 29, 2026

Study Record Updates

• Last Update Posted (Actual): August 7, 2026
• Last Update Submitted That Met QC Criteria: August 5, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: Muscle weakness; knee Osteoarthritis; Eccentric training,; Low-load blood flow restriction training
• Additional Relevant MeSH Terms: Neurologic Manifestations; Musculoskeletal Diseases; Nervous System Diseases; Muscular Diseases; Neuromuscular Manifestations; Pathologic Processes; Arthritis; Joint Diseases; Rheumatic Diseases; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Osteoarthritis; Osteoarthritis, Knee; Muscle Weakness
• Other Study ID Numbers: SEHRISH MALIK

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No