The goal of this clinical trial is to investigate the effect of oral hyaluronate in patients with knee osteoarthritis. The main question it aims to answer is: the therapeutic effect in the combined treatment of oral nutritional supplement based on hyaluronic acid with hyaluronic acid intra-articular Injection on symptomatic knee osteoarthritis. Researchers will compare it to those who receive only hyaluronic acid injection to see if the combined treatment is better.

Participants will receive a total of three months of oral hyaluronate or placebo agents.

Inclusion Criteria:

1. Radiological evidence of osteoarthritis Ahlbäck stage I-III.
2. Had knee effusion at the suprapatellar recess under ultrasonographic examination.
3. Age between 60 and 75 years old.

Exclusion Criteria:

1. Rheumatological disorders
2. Accidental trauma or fractures involving knees in the past three months
3. Neuropathic pain involving lower limbs
4. Central nervous system disorders including stroke, Parkinsonism, and spinal cord disorders.
5. Depression and cognitive problems
6. Pregnancy

The patients we recruited are not willing to share their individual data

both the patients and the investigators were blinded to the agent patients took