Allogenic Mesenchymal Stem Cell Intraarticular Injection for Knee Osteoarthritis Therapy (STEMJOINT)

Inclusion Criteria: Chronic knee pain (defined for at least 6 months with NRS 4 or above when pain worst) Patients with Grade II-III osteoarthritis according to the Kellgren Lawrence Classification and a joint width space of 1-3 mm. Axial hip, knee, ankle x-ray with no more than 5 degrees valgus/varus deformity Medial, lateral or dual compartment OA as determined above BMI <35 Danish speaker Patients must be legally competent and must be able to sign the written consent Exclusion Criteria: Severe Osteoarthritis (Grade IV according to Kellgren Lavrence Classification) Intraarticular tumor, infection or fracture Pregnancy and breast feeding Cognitive impairment Treatment with cytostatic drugs Previous intraarticular knee injection in the past 3 mo. Unable to perform MRI scan (non-compatible implants, claustrophobia and severe obesity(>BMI 35) Previous ligament reconstruction Meniscal operation with resection with more than 50% or multiple meniscal operations (more than one resection) Diabetes mellitus type 1 and 2 Knee instability and anterior-posterior laxity of 3mm or above on physical examination History of allergy to antibiotics Concomitant severe infection, malignant tumor, coagulation diseases or uncontrolled or unmanaged systemic disease Presence of other types of inflammatory arthritis