Participants with grade 3 and 4 knee osteoarthritis will recieve aspiration of synoivial fluid, and then receive either dextrose, hemaotopoietic stem cell, or platelet rich plasma, or no injection. The synovial fluid will be analyzed for changes in components.

80 participants with grade 3 and 4 symptomatic knee osteoarthritis, with a visable effusion, will receive aspiration of 3 ml of synovial fluid from the suprapatellar pouch, followed by either injection with 10 mL of 12.5% dextrose, 10 cc hematopoietic stem cells, 10cc PRP, or no injection into the suprapatellar pouch. They will then receive aspiration of 3 ml of synovial fluid at 2 days and either 7 days (for dextrose injected or no injection) or 14 days (stem cell and PRP injected) days post injection. These synovial samples will be analyzed for a change in components.

Inclusion Criteria:≥ 6 months of knee pain with walking

• ≥ 6/10 on a 0-10 point numerical rating scale
• High grade medial compartment cartilage loss ( Kellgren-Lawrence grade 3 or 4) on plain weight bearing X-ray
• Exposed subchondral bone at 110 degrees of flexion by ultrasound examination
• Easily visible suprapatellar pouch with quads conttraction.

Exclusion Criteria

• Current intake of NSAIDs or steroids
• Current anticoagulation therapy
• Inflammatory or post-infectious knee arthritis
• Systemic inflammatory conditions
• Knee flexion less than 100 degrees
• Knee extension less than 165 degrees
• Valgus or varus more than 15 degrees
• Any knee injection in the precedign 3 months
• BMI more than 50 kg/ meter squared
• Gross synovial folds on ultrasound.