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Differential Diagnosis for Right Knee Swelling

Single Most Likely Diagnosis

  • Osteoarthritis: This is a common condition, especially in older adults, characterized by wear and tear of the joint cartilage, leading to pain, stiffness, and swelling in the affected knee.

Other Likely Diagnoses

  • Ligament Sprain: Injury to the ligaments surrounding the knee can cause swelling, pain, and instability, especially if the sprain is severe.
  • Meniscal Tear: A tear in the cartilage of the knee (meniscus) can lead to swelling, pain, and mechanical symptoms like locking or catching of the knee.
  • Bursitis: Inflammation of the fluid-filled sacs (bursae) that cushion the knee joint can cause swelling and pain, often related to overuse or direct trauma.
  • Tendinitis: Inflammation of the tendons around the knee, such as the patellar tendon, can cause pain and swelling, typically related to overuse or repetitive strain.

Do Not Miss Diagnoses

  • Septic Arthritis: A bacterial infection within the joint space, which is a medical emergency requiring prompt antibiotic treatment to prevent joint destruction and systemic complications.
  • Deep Vein Thrombosis (DVT): A blood clot in the deep veins of the leg, which can cause swelling and pain, and has the potential to lead to life-threatening pulmonary embolism if not treated.
  • Osteonecrosis: Death of bone tissue due to lack of blood supply, which can cause pain and swelling in the knee, and may lead to collapse of the bone if not addressed.

Rare Diagnoses

  • Hemophilia: A genetic disorder that impairs the body's ability to make blood clots, leading to bleeding into joints, including the knee, causing swelling and pain.
  • Rheumatoid Arthritis: An autoimmune disease that can cause inflammation and swelling in multiple joints, including the knee, though it typically presents with symmetric joint involvement.
  • Tumor (Benign or Malignant): Though rare, tumors around the knee can cause swelling, pain, and other symptoms, and would require prompt investigation and treatment.
  • Pigmented Villonodular Synovitis (PVNS): A rare condition characterized by overgrowth of the joint lining, leading to swelling, pain, and potentially destructive changes within the joint.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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