This study is a randomized clinical trial designed to evaluate the usability and effectiveness of a tele-rehabilitation program in recreational athletes with Patellofemoral Pain Syndrome (PFPS). A total of 26 participants aged 18-35 years with unilateral PFPS will be randomly allocated into either a conventional physiotherapy group or a tele-rehabilitation group. Both groups will receive the same evidence-based exercise protocol comprising stretching, strengthening, balance, and functional exercises over a four-week period; however, the intervention group will perform the exercises remotely using the Physitrack mobile application with regular virtual supervision and progress monitoring, while the control group will receive face-to-face physiotherapy sessions. Primary outcome measures will include pain intensity assessed by the Numerical Pain Rating Scale (NPRS), knee range of motion measured using a universal goniometer, and quality of life evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS). The usability and patient satisfaction of the tele-rehabilitation platform will be assessed using the Telehealth Usability Questionnaire (TUQ). The findings of this study will determine whether tele-rehabilitation is a feasible, user-friendly, and effective alternative to conventional physiotherapy for improving clinical outcomes and rehabilitation accessibility in recreational athletes with PFPS.

Background:

Patellofemoral Pain Syndrome (PFPS) is one of the most common causes of anterior knee pain in recreational athletes, often resulting from overuse, muscle weakness, and abnormal patellar tracking. It causes pain during activities such as running, squatting, stair climbing, and jumping, leading to reduced physical performance and quality of life. Exercise-based physiotherapy is the recommended treatment; however, regular attendance at rehabilitation clinics may be limited by time, travel, cost, and accessibility .Tele-rehabilitation has emerged as an effective alternative by delivering supervised exercise programs through digital platforms, allowing patients to receive treatment remotely. Previous studies have demonstrated that tele-rehabilitation can reduce pain and improve function in various musculoskeletal conditions while enhancing accessibility and patient satisfaction. However, evidence regarding its usability and effectiveness in recreational athletes with PFPS remains limited. Therefore, this study aims to evaluate the effects of tele-rehabilitation on pain, knee range of motion, quality of life, and user satisfaction in recreational athletes with PFPS, providing evidence for its use as a practical alternative to conventional physiotherapy.

Objectives: The objective of this study is to evaluate the usability and effectiveness of tele-rehabilitation in recreational athletes with Patellofemoral Pain Syndrome (PFPS). Specifically, the study aims to determine the effect of tele-rehabilitation on pain intensity, knee range of motion, and quality of life, and to compare these outcomes with those of conventional physiotherapy. Pain intensity will be assessed using the Numerical Pain Rating Scale (NPRS), knee range of motion will be measured with a universal goniometer, quality of life and knee-related function will be evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the usability and patient satisfaction of the tele-rehabilitation platform will be assessed using the Telehealth Usability Questionnaire (TUQ).

Study Design: Randomized, parallel-group, assessor-blind clinical trial.

Setting: The University of Faisalabad ( Amin Campus and Saleem Campus)and The University of Agriculture , Faisalabad, Punjab, Pakistan.

Sample Size: Twenty-six participants (13 per group). Sample size calculated based on effect sizes from previous similar studies (Nilmart et al., 2024b) , with 10% allowance for attrition (n=2).

Eligibility Criteria :Eligible participants should be recreational athletes aged 18-35 years, both males and females. Participants must have experienced anterior or retro-patellar knee pain for at least one month, with a pain intensity of 3-6 on the Numerical Pain Rating Scale (NPRS), aggravated by activities such as squatting, stair climbing or descending, prolonged sitting, or knee flexion. A positive Patellar Apprehension Test, the ability to access a smartphone and the internet for tele-rehabilitation, and eligibility confirmed using the Kujala Anterior Knee Pain Questionnaire will also be required. Participants will be excluded if they have knee meniscal, ligamentous, or tendon injuries, knee effusion, patellar dislocation or subluxation, fractures, recent knee surgery, neuromuscular, metabolic, or rheumatologic disorders, or if they are unwilling or unable to provide informed consent.

Intervention Protocol:

Participants are randomly allocated into two groups: a conventional physiotherapy group (Group A) and a tele-rehabilitation group (Group B). Both groups follow the same standardized, evidence-based exercise program for 4 weeks, with two supervised sessions per week. The exercise protocol include stretching, strengthening, functional, and balance exercises, with the only difference being the mode of delivery.

Group A (Conventional Physiotherapy): Participants attend face-to-face physiotherapy sessions in the outpatient department under the direct supervision of a physiotherapist. The therapist will instruct, supervise, and progressively modify the exercises throughout the intervention period.

Group B (Tele-rehabilitation): Participants perform the same exercise program remotely using the Physitrack® mobile application. During the initial session, the physiotherapist install the application, educate participants on its use, and prescribe individualized exercises. Participants receive instructional videos, exercise reminders, and weekly progress updates through the application. The physiotherapist monitor adherence remotely, provide weekly telephone or video-call consultations, and adjust the exercise program according to each participant's progress.

The intervention should delivere in two phases. Weeks 1-2 focus on flexibility and early strengthening exercises, including hamstring, quadriceps, iliotibial band, and gastrocnemius stretching (2 sets of 30-second holds), quadriceps setting, seated knee extension, side-lying hip abduction (2 sets of 10 repetitions), and mini-squats (0-45° knee flexion; 2 sets of 10 repetitions). Weeks 3-4 emphasize progressive strengthening and neuromuscular control through side-lying hip abduction, prone hip extension, squats (45-60°), lunges (45°) (2 sets of 10-12 repetitions), and balance exercises including single-leg stance and single-leg heel raises (3 sets of 8-10 repetitions). Outcome measures would be recorded at baseline and at the completion of the 4-week intervention.

Outcome Measures:

Outcome measures would be assessed at two time points: pre-intervention (baseline, before the commencement of the 4-week rehabilitation program) and post-intervention (at the completion of the 4-week intervention). Pain intensity will be evaluated using the Numerical Pain Rating Scale (NPRS), an 11-point scale ranging from 0 (no pain) to 10 (worst imaginable pain). Knee range of motion (ROM), specifically knee flexion, will be measured in degrees using a universal goniometer. Quality of life and knee-related function will be assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS), which evaluates pain, symptoms, activities of daily living, sport and recreation function, and knee-related quality of life. The usability and patient satisfaction of the tele-rehabilitation intervention will be assessed only in the tele-rehabilitation group after completion of the intervention using the Telehealth Usability Questionnaire (TUQ), which measures ease of use, usefulness, interface quality, reliability, satisfaction, and future acceptance of the tele-rehabilitation platform.

Statistical Analysis: Intention-to-treat analysis will be used. Normality of data will be assessed by Shapiro-Wilk test. Within-group comparisons will use paired t-test for normally distributed data or Wilcoxon signed-rank test for non-normal data. Between-group comparisons will use independent t-test or Mann-Whitney U test. Significance level set at p ≤ 0.05. Results will be presented in graphical and tabular form using SPSS version (latest available).

Expected Outcomes:

It is expected that both the conventional physiotherapy and tele-rehabilitation groups will demonstrate improvements following the 4-week intervention. However, participants receiving tele-rehabilitation are anticipated to achieve clinically significant reductions in pain intensity, improved knee range of motion, and enhanced quality of life comparable to those receiving conventional physiotherapy. Additionally, the tele-rehabilitation group is expected to report high usability and patient satisfaction on the Telehealth Usability Questionnaire (TUQ), indicating that the digital rehabilitation platform is feasible, user-friendly, and acceptable for recreational athletes with Patellofemoral Pain Syndrome (PFPS). The findings are expected to support tele-rehabilitation as an effective and accessible alternative to conventional physiotherapy, particularly for individuals with limited access to in-person rehabilitation services.

Inclusion Criteria:

• Recreational athletes
• age between 18 and 35
• Males and females
• Unilateral Anterior knee pain between 3 to 6 on NPRS and retro patellar pain brought on by squatting, knee flexion, climbing, descending stairs, and extended sitting
• At least one month of knee pain
• Positive Apprehension test
• Can access the internet and smart phone
• Kujala questionnaire scale

Exclusion Criteria:

• Knee meniscus, ligament, and tendon injuries
• Knee effusion
• Dislocation of the patella, subluxation, and fractures
• Recent Surgery or fracture of the affected knee
• Neuromuscular, metabolic, and rheumatologic disorders.
• Who does not sign the consent form?