Table 1 Exclusion criteria

Related to the OA pathology

 ○ Radiographical Kellgren and Lawrence grade I or IV

 ○ Osteoarthritis secondary to a microcrystalline arthropathy: chondrocalcinosis previously known or defined by a calcium border on at least one tibiofemoral spacing, gout ……

 ○ Isolated femoropatellar OA

 ○ Presence of another joint (other than the evaluated knee) affected by OA (confirmed in radiographs and symptomatic)

 ○ Chondromatosis or villonodular synovitis of the knee

 ○ Paget disease

 ○ Recent trauma (<1 month) of the evaluated knee

 ○ Pathologies interfering with the evaluation of OA (radiculalgia in the lower limbs, arteritis…..)

 ○ Acute inflammatory osteoarthritis (Kofus ≥ 7)

Related to previous and concomitant treatments

 ○ Corticosteroids injection in the evaluated knee in the last month before injection

 ○ Hyaluronan injection in the evaluated knee in the last 6 months before injection

 ○ Acetaminophen and NSAIDs 48 h before inclusion visit

 ○ Change in the dosage of symptomatic slow-acting drugs i.e. chondroitin, glucosamine, diacerein or avocado-soybean unsaponifiables in the last 3 months before first injection

 ○ Arthroscopy and surgery in the target knee in the last 3 months before first injection

 ○ Oral corticotherapy

Related to associated pathologies

 ○ Severe diseases (liver or renal failure, uncontrolled cardiovascular diseases….)

 ○ Other inflammatory rheumatic diseases (e.g. rheumatoid arthritis)

 ○ Dermatological infection at the site of injection

 ○ Anticoagulant treatment

 ○ High risk of hemorrhage

Related to the patients

 ○ Allergy to hyaluronan and constituents (i.e. mannitol)

 ○ Allergy to acetaminophen

 ○ Pregnant or breastfeeding women

 ○ Premenopausal women without contraception

 ○ Unable to write

 ○ Participation to a therapeutic clinical trial in the last 3 months

 ○ Under guardianship or judicial protection