Overview
This study evaluates how acute mechanical loading affects cartilage degradation biomarkers in postmenopausal women with mild-to-moderate knee osteoarthritis. Participants will be grouped according to their existing antiresorptive treatment status: denosumab users, bisphosphonate users, and a control group. All participants will undergo a 30-minute treadmill walking session at a comfortable and tolerated speed. Blood samples will be collected immediately before and within 0-2 minutes after walking to measure changes in cartilage degradation biomarkers, including cartilage oligomeric matrix protein (COMP) and matrix metalloproteinase-3 (MMP-3). The study aims to determine whether the biomarker response to acute mechanical loading differs according to antiresorptive treatment status.
Eligibility
Inclusion Criteria:
- Postmenopausal women aged 60-80 years.
- DEXA-confirmed diagnosis of osteoporosis or osteopenia.
- Clinically and radiographically confirmed knee osteoarthritis, with Kellgren-Lawrence grade 2 or 3 in at least one knee.
- Knee MRI performed within the previous 3 months.
- Bilateral hand radiographs performed within the previous 6 months.
- Pain intensity of at least 20 mm on the Visual Analog Scale (VAS) during activity.
- Ability to tolerate the standardized acute mechanical loading protocol consisting of 30 minutes of treadmill walking.
- Non-sarcopenic status according to the STAR protocol.
- Ability to provide written informed consent.
Exclusion Criteria:
- Inflammatory arthritis, including rheumatoid arthritis, psoriatic arthritis, or ankylosing spondylitis.
- Active gout or calcium pyrophosphate deposition (CPPD) attack.
- History of total knee arthroplasty or major knee surgery.
- Intra-articular knee injection within the previous 12 months.
- Change in antiresorptive therapy within the previous 6 months.
- Previous osteoanabolic therapy.
- Systemic corticosteroid use for ≥3 months at a dose equivalent to ≥5 mg/day of prednisone.
- Glomerular filtration rate (eGFR) \<30 mL/min.
- New York Heart Association (NYHA) class III-IV heart failure.
- Uncontrolled diabetes mellitus or hypertension.
- Neurological disease significantly limiting walking.
- Cognitive impairment.
