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Why can hemophilia cause bleeding into joints after minor injuries?

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blood analysis The physical and chemical properties of a sample of blood are examined during blood analysis. The examination of blood is important for the accurate diagnosis of disease.

Hemophilia is a hereditary bleeding disorder characterized by a deficiency in essential blood coagulation proteins, most commonly factor VIII or factor IX.12

Because the blood lacks the necessary substances to form stable clots, individuals with this condition are unable to effectively stop bleeding after sustaining trauma. Consequently, even minor injuries—which might go unnoticed in a person without a clotting disorder—can trigger significant internal bleeding.13

When this bleeding occurs within the joints, it is known as hemarthrosis. Because the body cannot quickly seal the damaged blood vessels, blood accumulates in the joint space, leading to swelling, pain, and, if the bleeding is recurrent, potential long-term joint damage or loss of mobility. Managing these episodes typically requires the replacement of the missing clotting factor through medical infusion.312