Differential Diagnosis for Bilateral Knee Pain
Single Most Likely Diagnosis
- Osteoarthritis (OA): This is the most common cause of knee pain in older adults, especially when it worsens with weight-bearing activities like standing or walking and improves with rest. The bilateral nature of the pain also supports this diagnosis, as OA often affects multiple joints.
Other Likely Diagnoses
- Rheumatoid Arthritis (RA): Although less common than OA, RA can cause bilateral knee pain and stiffness, particularly in the morning or after periods of inactivity. The pain in RA tends to improve with activity but can worsen as the disease progresses.
- Meniscal Tears or Degeneration: Tears or degeneration of the menisci, the cartilage structures within the knee joint, can cause pain, especially with twisting or bending movements. This condition is common in older adults and can be bilateral.
- Bursitis: Inflammation of the bursae, fluid-filled sacs that cushion the knee joint, can cause pain and swelling. This condition can be related to overuse, direct blows to the knee, or infections.
Do Not Miss Diagnoses
- Septic Arthritis: Although less likely, septic arthritis is a medical emergency that requires prompt diagnosis and treatment. It can present with sudden onset of pain, swelling, and decreased range of motion in one or both knees, especially in the context of fever or recent infection.
- Osteonecrosis (Avascular Necrosis): This condition, characterized by the death of bone tissue due to a lack of blood supply, can cause severe knee pain. It is more common in individuals with risk factors such as long-term corticosteroid use, excessive alcohol consumption, or certain medical conditions.
- Tumors (Benign or Malignant): Although rare, tumors within or around the knee joint can cause pain, swelling, and decreased mobility. Early detection is crucial for effective treatment.
Rare Diagnoses
- Pseudogout (Calcium Pyrophosphate Deposition Disease, CPPD): This condition involves the deposition of calcium pyrophosphate dihydrate crystals within the joint, leading to sudden, severe pain and swelling, often mimicking the symptoms of gout.
- Hemochromatosis: A genetic disorder leading to excessive iron accumulation in the body, which can cause joint pain and arthritis, among other symptoms.
- Wilson's Disease: A rare genetic disorder that leads to copper accumulation in the body, potentially causing joint pain and other systemic symptoms.