Effects of Pulsed Electromagnetic Field Therapy on Meniscal Healing, Symptom Relief, and Knee Function

A musculoskeletal radiologist, blinded to the participants' group assignments and clinical details, will perform these assessments using fat- suppressed T2-weighted imaging. The primary imaging endpoint will be the between-group difference in the mean change of the intrameniscal fluid-equivalent signal area (mm2) from baseline to 6 months. The fluid-equivalent signal area will be delineated and quantified using standardized region-of-interest (ROI) methods on consecutive slices encompassing the original tear site.

The KOOS score is a 42-item patient-reported outcome measure assessing five subscales: Pain (9 items, score range 0-100), Symptoms (7 items, 0-100), Activities of Daily Living (17 items, 0-100), Sport/Recreation Function (5 items, 0-100), and Quality of Life (4 items, 0-100). Each subscale is scored separately from 0 (extreme problems) to 100 (no problems), with higher scores indicating better outcomes.

The WOMET is a 16-item patient-reported questionnaire assessing meniscal tear-related quality of life across three domains: Physical Symptoms (10 items), Sports/Recreation/Work/Lifestyle (4 items), and Emotions (2 items). Each item is scored from 0 (no problem) to 5 (extreme problem), with total scores transformed to a 0-100 scale where 0 represents the best possible status and 100 represents the worst possible status. Higher scores indicate worse outcomes.

Participant-initiated knee flexion-extension range measured in degrees using standardized goniometry, recording movement from full extension to maximum voluntary flexion.

Researcher-assisted knee flexion-extension range measured in degrees using standardized goniometry, recording movement from full extension to maximum assisted flexion without participants' muscle activation

Quantifies lower limb functional strength and endurance by counting the maximum number of full sit-to-stand cycles completed in 60 seconds from a standardized-height chair. Higher counts indicate better functional performance.

The maximum number of complete step-up cycles performed in 30 seconds on a standardized step. Higher counts indicate better unilateral strength.

Quantifies unilateral lower limb strength by counting the maximum number of complete step-down cycles performed in 30 seconds on a standardized step. Higher counts indicate better unilateral strength and eccentric control.

Oxygenation saturation levels (%) measured by photoacoustic ultrasound around the meniscal tissue area.

Vascularity levels (AU) measured by photoacoustic ultrasound around the meniscal tissue area.

Meniscal structural integrity assessed via standardized ultrasound protocol using a validated 4-point scale where higher grades indicate worse pathology.

A re-injury or new ligament injury will be confirmed if both clinical examination indicates instability or significant changes from baseline, and MRI shows new or worsened structural damage compared to baseline images. We will document all instances of re-injury or new ligament injuries, including their nature and severity. The incidence of re-injuries and new ligament injuries will be compared between the PEMF and control groups, and we will analyze any correlation between meniscal healing status and the occurrence of re-injuries.

Quantitative postural control assessment during 10-second standing on the Zebris stance analysis system, which consists of a capacitance-based foot pressure platform inserted within a treadmill. Parameters include postural sway and weight distribution such as sway area, forefoot vs heel force ratio, left vs right symmetry

Quantitative gait analysis during 5-minute walking on the Zebris gait analysis system, which consists of a capacitance-based foot pressure platform inserted within a treadmill. Spatiotemporal parameters (gait speed, step length, stride length, cadence), dynamic balance (centre of pressure path length, lateral symmetry index), and load distribution metrics (peak heel/forefoot pressure, weight transfer timing) will be collected.

Quantitative gait analysis during a 5-minute run on the Zebris gait analysis system, which consists of a capacitance-based foot pressure platform inserted within a treadmill. Spatiotemporal parameters (gait speed, step length, stride length, cadence), dynamic balance (centre of pressure path length, lateral symmetry index), and load distribution metrics (peak heel/forefoot pressure, weight transfer timing) will be collected.