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Knee osteoarthritis — SCE Rheumatology MCQ

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ModerateMusculoskeletal MedicineKnee osteoarthritisSCE Rheumatology

A 73-year-old man with radiographic knee osteoarthritis has a recurrent tense right-knee effusion causing substantial pain and restriction despite exercise therapy, weight management and topical NSAID treatment. There is no fever, overlying erythema, recent infection or joint prosthesis. C-reactive protein is normal. Ultrasound-guided aspiration followed by intra-articular triamcinolone is planned. He takes apixaban 5 mg twice daily for atrial fibrillation with a previous transient ischaemic attack. His platelet count and liver function are normal, estimated glomerular filtration rate is 68 mL/min/1.73 m², and he takes no antiplatelet drug. He has no history of abnormal bleeding. Which is the most appropriate peri-procedural anticoagulation plan?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: E — Continue apixaban without interruption and perform the aspiration and injection

Explanation lettering: D = shown as A · E = shown as B · B = shown as C · A = shown as D · C = shown as E

Intra-articular injection and arthrocentesis are low-bleeding-risk procedures. EULAR states that intra-articular therapy is not contraindicated in patients taking antithrombotic medication unless their individual bleeding risk is high. Observational evidence reviewed by EULAR estimated a periprocedural bleeding risk of 0–2%, including no reported bleeding in 1,050 procedures performed while patients continued a direct oral anticoagulant. This patient has normal platelets, preserved renal and hepatic function, no concomitant antiplatelet treatment and no bleeding history. There is therefore no high-risk feature justifying interruption. Continuing apixaban also avoids unnecessary loss of stroke protection in a patient with previous cerebral ischaemia. A and B apply interruption schedules appropriate to procedures with materially greater bleeding consequences, not uncomplicated peripheral arthrocentesis or injection. D may appear to balance bleeding and thrombosis, but even this brief interruption is unnecessary in a patient without increased bleeding risk. E is inappropriate because bridging a direct oral anticoagulant with low-molecular-weight heparin does not reduce procedural bleeding and introduces additional anticoagulant exposure and complexity. Standard aseptic technique, careful needle placement and post-procedure local pressure are appropriate.

Reference: EULAR recommendations for intra-articular therapies (25 May 2021) — https://ard.bmj.com/content/80/10/1299 EULAR Recommendations: Recommendations for Management (Checked 19 August 2026) — https://www.eular.org/recommendations-management The Risk of Bleeding Complications in Intra-Articular Injections and Arthrocentesis in Patients on Novel Oral Anticoagulants: A Systematic Review (6 September 2021) — https://pubmed.ncbi.nlm.nih.gov/34659968/