Patello Femoral Pain Syndrome
Conditions
Keywords
Patellofemoral pain, Blood flow restriction training, Quadriceps strength, Athletic Performance, resistance training
Brief summary
This randomized controlled trial compares blood flow restriction (BFR) resistance training (leg press and seated knee extension at 30% 1RM) versus BFR cycling (stationary cycling at low resistance) in 60 athletes (aged 18-40 years) diagnosed with patellofemoral pain syndrome. Both interventions are delivered over 8 weeks (3 sessions/week) with a pneumatic cuff set at 80% limb occlusion pressure. Primary outcomes include pain intensity (NPRS), quadriceps strength (handheld dynamometer), and functional ability (Kujala Anterior Knee Pain Scale), assessed at baseline and post-intervention.
Detailed description
Patellofemoral pain (PFP) is among the most prevalent musculoskeletal conditions in athletes, with reported prevalence of 30-40% in sports populations. High-load resistance training is the conventional rehabilitation approach but often exacerbates joint stress and reduces adherence. Blood flow restriction (BFR) training enables strength gains at low loads by applying a pneumatic cuff at 80% LOP on the proximal thigh. This trial compares two BFR modalities: * Group A (BFR-RT): Leg press and seated knee extension, 1x30 + 3x15 reps at 30% 1RM, 3x/week for 8 weeks. * Group B (BFR-CYC): Stationary cycling at low resistance, 4x5-minute intervals at 70-80 RPM (RPE 11-13), 3x/week for 8 weeks. All sessions are supervised one-on-one by a physiotherapist. Assessments are conducted at baseline and week 8. The study is single-blinded (outcome assessor blinded). Randomization via computer-generated sequence. Statistical analysis via SPSS v27 (paired t-test / Wilcoxon for within-group; independent t-test / Mann-Whitney for between-group, alpha=0.05).
Interventions
Participants will undergo blood flow restriction (BFR) resistance training using a pneumatic cuff applied to the proximal thigh at 80% limb occlusion pressure. Exercises include leg press and seated knee extension performed at 30% of one-repetition maximum (1RM). Training will be conducted for 8 weeks, with supervised sessions 3 times per week. Cuff pressure will be monitored and adjusted using BP cuff. The aim is to improve quadriceps strength and reduce pain in patients with patellofemoral pain.
DEVICEBlood Flow Restriction Cycling
Participants will perform stationary cycling combined with blood flow restriction (BFR) applied to the proximal thigh at 80% limb occlusion pressure. Cycling will be performed at low resistance with controlled cadence for 8 weeks, 3 sessions per week under physiotherapist supervision. The protocol includes structured cycling intervals with rest periods and continuous monitoring of pain and perceived exertion. The intervention aims to improve quadriceps strength, reduce pain, and enhance functional outcomes in patients with patellofemoral pain.
Sponsors
Ibadat International University, Islamabad
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
This is a single-blinded study in which the outcome assessor is blinded to group allocation. Participants and treating physiotherapists are aware of the assigned intervention due to the nature of exercise-based rehabilitation. Efforts are made to standardize instructions and interaction across both groups to minimize bias.
Intervention model description
This study is a parallel-group randomized controlled trial comparing two active intervention arms: blood flow restriction resistance training and blood flow restriction cycling in patients with patellofemoral pain.
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
No
Inclusion criteria
1. Male and female athletes aged 18-40 years 2. Clinically diagnosed with patellofemoral pain syndrome 3. Anterior or retropatellar knee pain of at least 3 months duration 4. Pain provoked by at least two functional activities (e.g., squatting, stair climbing, running, prolonged sitting) 5. Willingness to participate and provide written informed consent
Exclusion criteria
1. History of knee surgery or significant knee trauma in the past 6 months 2. Presence of ligament, meniscal, or cartilage injuries 3. Neurological, vascular, or systemic inflammatory conditions 4. Contraindications to BFR training (e.g., deep vein thrombosis, uncontrolled hypertension) 5. Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Quadriceps Strength - Handheld Dynamometer | Baseline (Week 0) and Post-intervention (Week 8) | Isometric quadriceps muscle strength measured in Newtons using a calibrated handheld dynamometer (ICC \> 0.90). Measurement taken in a standardized seated position at 60° knee flexion. |
| Pain Intensity - Numeric Pain Rating Scale (NPRS) | Baseline (Week 0) and Post-intervention (Week 8) | Self-reported pain intensity rated on a 0-10 scale (0 = no pain, 10 = worst imaginable pain). The NPRS has excellent test-retest reliability (ICC 0.95). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Functional Outcomes - Kujala Anterior Knee Pain Scale (AKPS) | Baseline (Week 0) and Post-intervention (Week 8) | 13-item patient-reported outcome measure assessing functional limitations due to anterior knee pain. Scored 0-100 (higher = better function). High internal consistency (α = 0.83-0.91). |
Countries
Pakistan
Contacts
CONTACTHaroon Khan, MS. Sports Physical Therapy
CONTACTHafsah Gul Khattak, DPT, MS-NMPT
PRINCIPAL_INVESTIGATORHafsah Gul Khattak, DPT, MS-NMPT
IBADAT INTERNATIONAL UNIVERSITY, ISLAMABAD (IIUI)
Outcome results
None listed