Clopidogrel-induced hemarthrosis following knee replacement

Area of Science:

• Cardiology
• Pharmacology
• Rheumatology

Background:

• Clopidogrel is a widely prescribed P2Y12 inhibitor used to prevent ischemic events in atherosclerotic vascular disease.
• Adenosine diphosphate receptor antagonism is the mechanism of action for clopidogrel.
• Current literature lacks reports of spontaneous hemarthrosis linked to clopidogrel monotherapy.

Observation:

• A 62-year-old female patient presented with spontaneous hemarthrosis of the left knee.
• The patient was undergoing treatment with clopidogrel.
• No prior history of joint issues or trauma was noted.

Findings:

• The Naranjo Causality Assessment Scale indicated a probable link (score of 5) between clopidogrel use and the hemarthrosis.
• Discontinuation of clopidogrel and conservative management, including joint aspiration, were initiated.
• Prompt intervention helped prevent further joint damage.

Implications:

• Spontaneous hemarthrosis should be considered a potential complication of clopidogrel therapy.
• Clinicians should assess for intra-articular effusion and pain in patients on clopidogrel.
• Early diagnosis and management are essential for favorable patient outcomes.