Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: July 16, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Differential Diagnosis for Visible Swelling on Both Knees

Single Most Likely Diagnosis

  • Osteoarthritis (OA): This is a common condition characterized by wear and tear of the joint cartilage and underlying bone, leading to pain and swelling. It often affects both knees symmetrically, especially in older adults.

Other Likely Diagnoses

  • Rheumatoid Arthritis (RA): An autoimmune disorder that causes inflammation and swelling in multiple joints, including the knees. It typically presents with symmetrical joint involvement.
  • Gout: A form of inflammatory arthritis characterized by sudden, severe attacks of pain, swelling, redness, and tenderness in one or more joints, most often the big toe, but can also affect the knees.
  • Meniscal Tears or Ligament Sprains: Injuries to the cartilage or ligaments within the knee joint can cause swelling, pain, and limited mobility. These can occur bilaterally due to repetitive strain or trauma.
  • Bursitis: Inflammation of the fluid-filled sacs (bursae) that cushion bones, tendons, and muscles near joints, which can cause swelling and pain.

Do Not Miss Diagnoses

  • Septic Arthritis: A serious infection within a joint that requires immediate medical attention. Symptoms include severe pain, swelling, redness, and warmth of the affected joint.
  • Lymphoma or Other Malignancies: Although rare, certain types of cancer can cause joint swelling. It's crucial to consider this possibility, especially if other systemic symptoms are present.
  • Osteonecrosis (Avascular Necrosis): The death of bone tissue due to a lack of blood supply, which can cause pain and swelling in the affected joint.

Rare Diagnoses

  • Hemophilia: A genetic disorder that impairs the body's ability to make blood clots, a process needed to stop bleeding. Joint swelling and pain can occur due to bleeding into the joints.
  • Pseudogout (Calcium Pyrophosphate Deposition Disease, CPPD): A type of arthritis that causes sudden, severe joint pain and swelling, similar to gout, but caused by calcium pyrophosphate dihydrate crystal deposition.
  • Sarcoidosis: A condition in which inflammatory cells (granulomas) form in various organs, including the lungs, skin, and joints, leading to symptoms like joint pain and swelling.

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.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.