The study has only enrolled 6 subjects in 6 months since study initiation. Potential participants are unwilling to participate in the study due to the randomziation and blinding. Both aspects are needed to ensure a robust comparison between groups.

This study is a 3-arm, double-blind, randomized trial comparing the clinical outcomes of Zilretta, Synvisc One, and Monovisc for knee OA.

Knee osteoarthritis (OA) is a leading cause of disability worldwide.1,2 Standard of care treatments for knee OA include activity modification, weight loss, therapeutic exercise and medications like non-steroidal anti-inflammatory drugs (NSAIDs). If these measures fail, injections like corticosteroids and hyaluronate (HA) can be helpful for pain control.3

The aforementioned injections have unique mechanisms of action. Steroid injections work through reducing joint inflammation, while HA works by lubricating and cushioning the joint. There are several varieties of steroids and HA injections that have been approved by the Food and Drug Administration for use in knee OA.

Among these variations are extended-release triamcinolone (Zilretta), hylan GF-20 (synvisc one), and hyaluronan (monovisc). While each are FDA approved and commonly used in orthopedic and sports medicine clinics, they have never been directly compared in any study. Therefore, when selecting a treatment for a patient, it is largely based on provider preference, not clinical data.

This study is a 3-arm, double-blind, randomized trial comparing the clinical outcomes of Zilretta, Synvisc One, and Monovisc for knee OA.

Inclusion Criteria:

• Age 25-85 years
• BMI < 40
• Diagnosis of unilateral knee OA
• Radiographic evidence of OA of the target knee (Kellgren-Lawrence grades 2-4)
• Continued OA pain in the target knee despite at least 6 weeks of: physical therapy and at least one of the following: activity modification (such as reducing impact on the knee), weight loss, and a 2 week trial of NSAID / acetaminophen.
• Knee Osteoarthritis Outcomes Score (KOOS)-Pain subscale 20-65
• Working knowledge of English language (to be able to complete all outcome scores)
• Ability to attend all follow-up appointments

Exclusion Criteria:

• 3+ effusion of the target knee (stroke test grading system)

• Prior injection therapy:

  • Steroid injection in target knee in the last 3 months
  • Viscosupplementation in target knee in the last 6 months
  • PRP in the target knee in the last 6 months
  • Cellular treatments in index knee (bone marrow, amniotic suspensions etc) 1 year
  • Participation in any experimental device or drug study within 1 year before screening visit

• Oral or IM steroids in the last 3 months (Inhaled steroids used in the treatment of asthma/allergies are permitted)

• Medical condition that may impact outcomes of procedure including:

  • Systemic inflammatory disorders that impact the joints like rheumatoid arthritis, lupus, etc
  • Undergoing current cancer treatment (other than non-melanoma skin malignancies)

• Taking immunosuppressants

• Previous cartilage repair procedure on the injured cartilage surface (ie, OATS, ACI, MFX) in the last 5 years

• Previous surgery at the target knee within the past 1 year

• Any degree of cognitive impairment

• Symptomatic OA of any other joint in the lower limbs

• Pregnancy, lactating, or intent to become pregnant during treatment period (Female participants will be asked if they are pregnant, lactating, or intend to become pregnant during treatment)

• Gout, Pseudogout (including radiographic evidence of chondrocalcinosis)

• History of infection or current infection at the affected joint

• Smoking (Former smokers< 1 year from quit date)

IDP will not be shared.