The aim of this study is to compare functional and clinical outcomes of intraarticular injections of hyaluronic acid and steroids in patients with bilateral knee osteoarthritis. We will compare clinical and functional outcomes for each knee separately after week 6, month 3, month 6, and one year after the intervention.

We will include patients with bilateral knee osteoarthritis (Kellgren Lawrence grades 2 and 3). On initial examination, we will measure active and passive range of flexion and extension, presence of swelling, joint effusion, VAS score for each knee separately, and WOMAC score for every knee separately. We will randomly apply hyaluronic acid injection in one knee and steroid injection in the other knee. We will repeat the same examination after week 6, month 3, month 6, and one year after the procedure. The main aim is to check whether there is a significant clinical or functional difference between two groups.

Inclusion Criteria:

• bilateral knee pain
• same grade of osteoarthritis in both knees
• Kellgren-Lawrence grade 2 or 3 of knee osteoarthritis
• fully completed all follow-up examinations

Exclusion Criteria:

• unilateral knee osteoarthritis
• different grade of osteoarthritis between knees based on Kellgren-Lawrence scale
• positive history of previous knee interventions (injections, surgery)
• positive history of additional knee injuries (meniscus, ligament...)

All collected IPD, all IPD that underlie results in a publication.