Osteoarthritis (OA) is a prevalent chronic condition which most commonly affects the knee. The pathogenesis of OA involves initial mechanical stress resulting in cartilage lesions, leading to inflammatory processes causing joint degradation. Numerous pharmacological and non-pharmacological therapies have been employed, including hyaluronic acid (HA) supplementations to alleviate the joint damage from mechanical load by acting as a shock absorber which provides lubrication, and intra-articular corticosteroid injections to reduce inflammation. However, HA is unable to facilitate cartilage regeneration and corticosteroids has numerous undesirable side effects which render them unsustainable treatment options.

Recently, many studies worldwide have demonstrated that platelet-rich-plasma (PRP) stimulates cartilage repair by actively secreting growth factors which activate cell proliferation and differentiation thereby promoting tissue regeneration. However, there has been varying results across various RCTs due to the heterogeneity of studies, with inconclusive recommendations on the treatment regimen for PRP-HA. Currently, PRP treatment is also not formally recognized as a treatment modality for knee OA in many countries, including Singapore.

This randomised controlled trial aims to compare the efficacy of Cellular Matrix (CM) PRP-HA versus HA (Synolis VA) intra-articular injections in knee OA through quantifying the improvement in long-term treatment outcomes such as pain, stiffness, and functional impairment, potentially improving the quality of life for many patients with knee OA.

In vitro experimentations have also established the efficacy of PRP, where chondrocytes stimulated with PRP has shown to increase proteoglycan and collagen synthesis which bears similar biochemical qualities to that of hyaline cartilage. PRP has also shown to provide more critical growth factors (including PDGF, TGF-beta, IGF, EGF, VEGF, FGF) than conventional culture media, increasing the synthesis of major cellular proteins and collagen in the extracellular component of intervertebral disc cells, potentially enhancing the functional properties of joint cartilages.

Presently, cellular matrix (CM) remains as the only device which allows for the combination of PRP and HA to be delivered to patients within a single intra-articular injection. However, there are insufficient large-scale studies to reliably evaluate the efficacy of PRP-HA on knee OA and formulate a universal recommendation on its treatment regimen. There are also no RCTs conducted on our local population to explore the effects of CM-PRP-HA on knee OA.

Inclusion Criteria:

• Patients of age 30 years and above
• Radiographical diagnosis of knee OA - ie narrowing of joint space, presence of osteophytes, possible sclerosis and subchondral cysts
• History of chronic pain in knee or knee swelling for at least 3 months
• Ability of patients to provide informed consent

Exclusion Criteria:

• Concurrent complementary and alternative medicine (CAM) treatments e.g. acupuncture
• Inflammatory diseases / infection / fracture / trauma
• Malignancies
• Pregnant or lactating females
• Consistent use of NSAIDs within 48 hours of procedure
• Corticosteroid injection at treatment site within 1 month
• Systemic use of corticosteroids within 2 weeks
• Tobacco use
• (For patients receiving PRP-HA injection only): Hemoglobin <10 g/dL and platelets <150,000/mm3

Aggregate data will be made available