Participants allocated to the Hybrid Telerehabilitation group will receive a combination of face to-face and remotely supervised exercise sessions over the 6-week intervention period.

Face-to-face sessions will be used for comprehensive movement assessment, hands-on instruction of new exercises, verification of correct technique, and progression of exercise intensity and resistance. Remotely supervised sessions will be conducted using a secure video-conferencing platform (e.g., Zoom), allowing real-time visual monitoring of exercise execution and provision of verbal and visual feedback by the therapist. Camera positioning guidelines will be provided to ensure adequate visualization of frontal and sagittal plane lower-limb alignment during exercises, particularly during closed-chain and functional tasks.

Participants in the Telerehabilitation group will complete all 18 exercise sessions (3 sessions per week for 6 weeks) remotely without attending in-person clinic visits. All sessions will be supervised synchronously by the same physical therapist using a real-time video-conferencing platform (e.g., Zoom). Before the start of the intervention, participants will receive standardized instructions regarding camera placement, exercise space setup, and safety considerations to ensure accurate observation of movement quality during training sessions.

Participants assigned to the Conventional Physical Therapy group will receive all 18 exercise sessions through traditional face-to-face supervised treatment at the outpatient physical therapy clinic. Sessions will be conducted three times per week for six consecutive weeks, under the direct supervision of a licensed physical therapist. This model represents standard clinical practice for the management of patellofemoral pain syndrome and allows continuous monitoring of exercise performance, immediate correction of faulty movement patterns, and direct verbal feedback during training. During each session, the therapist will ensure correct execution of both hip- and knee focused exercises, reinforce appropriate lower-limb alignment, and adjust exercise intensity and resistance according to predefined progression criteria.

All three groups (Hybrid Telerehabilitation, Pure Telerehabilitation, and Conventional Physical Therapy) followed identical exercise progressions over 6 weeks (3 sessions/week, 18 sessions total) targeting proximal hip and knee strengthening. Exercise dosage, intensity, and progression remained standardized across delivery modes to isolate rehabilitation method effects. The exercise program will progress through three phases to allow gradual restoration of strength, control, and functional ability.

The pain intensity was assessed using the Visual Analogue Scale (VAS), where patients rated their pain at rest and during movement over the previous week on a 0-10 cm scale, with 0 indicating no pain and 10 representing unbearable pain. Pain scores were recorded before and after the intervention. Interpretation of clinical relevance often goes beyond statistical significance, and the minimal clinically important difference (MCID) for pain intensity on the VAS has been investigated in a range of musculoskeletal conditions

Knee function will be evaluated using the Kujala Anterior Knee Pain Scale (AKPS), which is a condition-specific, self-administered questionnaire designed to assess pain severity and functional limitations associated with patellofemoral pain syndrome. Participants will be asked to complete the questionnaire independently by responding to 13 weighted items that address symptoms and difficulty during daily and sports-related activities that load the patellofemoral joint, including walking, running, stair climbing, squatting, jumping, and prolonged sitting with the knee flexed

A two-dimensional video analysis measured the knee valgus/varus frontal-plane projection angle (FPPA) during the Single-Legged Drop Jump test following established methodology