Ultrasound Guided vs Unguided Intra-articular Knee Injections

Accuracy of Ultrasound Guided Versus Unguided Intra-articular Knee Injections in a Difficult to Inject Population

To determine the accuracy of unguided versus ultrasound (US) guided knee joint injections in obese patients with no clinically detectable effusion.

Patients with BMI > 30 and no clinically detectable knee effusions, with clinical symptoms and radiographic evidence of knee osteoarthritis or inflammatory arthritis, who have been referred for an intraarticular knee injection with corticosteroid will be randomized to either receive ultrasound guidance or not receive ultrasound guidance for their injection. One group will use the ultrasound guidance to position the needle. The other group will use landmarks to position the needle. For both groups, once the proceduralist is comfortable with needle placement for the injection, contrast dye will be injected and fluoroscopy used, to determine if the needle placement is correct. If it is determined the needle placement is not correct, fluoroscopy will be used to reposition it. Once needle placement is determined to be acceptable, the injection will be given. Patient demographics will be collected, along with pain scores preprocedure and two weeks post-procedure.

Subjects are responsible for all clinical costs associated with the injection.

There is no remuneration offered for study participation.

Inclusion Criteria

• BMI > 30
• No clinically detectable knee effusion
• Clinical or radiographic evidence of knee osteoarthritis or inflammatory arthritis
• Must be referred to the Pain Clinic for treatment

Exclusion Criteria

• History of surgery on the affected knee
• Evidence of untreated systemic infection or systemic immunocompromise
• Evidence of cutaneous infections near the study knee injection site
• Patients on warfarin with an INR > 3.0
• Patients on oral antiplatelet or anticoagulant medications will be excluded if they have documented evidence of renal insufficiency (GFR < 60)
• History of iodinated contrast allergy or significant reaction to corticosteroids or lidocaine