Step 4: Read and complete the decision guide to learn more about your symptoms.
Persistent Knee Swelling
Blood in the Joint
Bleeding into the joint is fairly common after an injury; in fact, for persons skiing or playing competitive sports associated with sudden stops, starts, turns or contact (including basketball, football and soccer), an injury associated with marked knee swelling is usually due to bleeding in the joint and often indicates a significant problem inside the joint such as torn cartilage (also called a torn meniscus), a ligament injury or even a fracture.
Other, much less common causes, of bleeding into the joint are hemophilia (or other bleeding disorders), use of medications that thin the blood (such as warfarin/coumadin), vitamin C deficiency (scurvy), and joint tumors.
Would you like to continue reading more about causes of knee swelling (next up: bony enlargement) or would you rather move on to some questions about your specific situation?