Overview

Health care costs are increasing alarmingly, which will impose an overwhelming economic burden to an aging society like that of Hong Kong. For example, degenerative musculoskeletal disorders such as osteoarthritis (OA) present a grand challenge with its high prevalence (>40% in the elderly suffered from knee OA). OA is a debilitating progressive disease with typical symptoms such as acute pain causing loss of mobility Currently there is no cure for OA. Pharmacological treatment and new regenerative technologies such as stem cell therapy are actively being developed, but most of these options are very expensive per se, and side effects are not uncommon. Costeffectiveness is also a major consideration for devising new therapeutic modalities for OA.

There are emerging evidences showing that pulsed electromagnetic field (PEMF) can modulae mitochondrial activities for muscle gain. PEMF exposure on top of regular exercise training may promote muscle regeneration and tissue healing.

This study aims to conduct a double-blinded, randomized controlled trial to investigate the effect of PEMF treatment on knee pain in patients with knee OA. We hypothesize that PEMF treatment is effective to relief in pain and improve knee function in Knee OA subjects.

Based on the aim of this study, older adult patients (aged 50 or above) with knee OA with Kellgren-Lawrence grade 2-4 by X-ray, have sedentary lifestyle (Tegner activity level less or equal to 3), no acute knee injuries in past 12 months, no muscle strain in past 12 months and not degenerative joint disease in other joints except the involved knee.

To estimate the improvement of patients, isometric quadricep muscle strength, posture assessment, serum myokine level, serum vitamin D level and selfreported outcome with questionnaires will be performed.

Eligibility

Inclusion Criteria:

1. Age 50 or above
2. knee OA with Kellgren-Lawrence grade 2-4 by X-ray
3. Sedentary lifestyle (Tegner activity level ≤ 3)
4. No acute knee injuries in past 12 months
5. No muscle strain in past 12 months
6. No degenerative joint diseases in other joints except the involved knee

Exclusion Criteria:

1. Age smaller than 50 years old
2. Experienced any concomitant bone fracture, ACL injury, major meniscus injury
3. Any rheumatological diseases
4. Metal implants that would cause interference on MRI
5. Previous contralateral knee injury
6. Recent knee injections (prior 3 months)
7. Physical inability to undertake testing procedures
8. Pregnancy or possibility of pregnancy