Loaded and Unloaded Magnetic Resonance (MR) Imaging of Meniscus-Cartilage-Trabecular Bone in Osteoarthritis

Inclusion Criteria:

• Men and women
• At least 35 years of age
• Mild OA patients with arthritic knee symptoms and KL score of 1-2
• Severe OA patients with arthritic knee symptoms and KL score of 3-4
• Knee symptoms in OA patients is defined as pain, aching, or stiffness on most days of a month during the past year or use of medication for treatment of knee pain on most days of a month during the past year
• self reported knee pain (defined as medial compartment knee pain at least 1 day per week during each of the 6 weeks prior to participation) and at least 3 of the following 6 clinical indicators: Age>50 years; morning stiffness<30 minutes duration; crepitus on active motion; tenderness of the bony margins of the knee joint; bony enlargement at the knee; and lack of palpable warmth of the synovium

Exclusion Criteria:

• current use of investigational drug
• conditions other than OA which limit lower extremity function and mobility and/or would confound the evaluation of function (e.g., clinically significant spinal disc degeneration, painful or dysfunctional feet, peripheral vascular disease, lumbar radiculopathy, trochanteric bursitis, hip pain, lumbar pain)
• Patients with metallic fragments in the eyes, vascular clips, pacemakers, and other contraindications to MRI
• History of joint replacement, intra-articular fracture, osteotomy, arthroplasty or meniscectomy of the signal knee
• History of other disease that may involve the study joint including systemic inflammatory disease, crystalline disease, knee infection of the signal knee, avascular necrosis, Paget's disease or tumors
• Self reported heart condition that limits any daily physical activity
• Patients who are pregnant