Differential Diagnosis for Knee Pain Worsening While Walking Down Stairs
Single Most Likely Diagnosis
- Patellofemoral Pain Syndrome (PFPS): This condition is characterized by pain around or behind the patella, often exacerbated by activities that put stress on the knee, such as walking down stairs. The mechanism involves abnormal tracking of the patella within the femoral groove, leading to increased stress and potential cartilage damage.
Other Likely Diagnoses
- Osteoarthritis (OA): Knee OA can cause pain that worsens with weight-bearing activities, including walking down stairs. The pain is typically localized to the joint and can be accompanied by stiffness and limited range of motion.
- Meniscal Tears: Tears in the menisci, which are cartilage structures within the knee joint, can cause pain, especially with twisting or bending movements. Walking down stairs can exacerbate the pain due to the increased stress on the knee joint.
- Ligament Sprains: Sprains to the ligaments surrounding the knee can cause pain, instability, and stiffness. Activities like walking down stairs can increase the stress on these ligaments, worsening the pain.
Do Not Miss Diagnoses
- Septic Arthritis: Although less common, septic arthritis is a medical emergency that requires prompt diagnosis and treatment. It can present with acute onset of knee pain, swelling, and decreased range of motion, and can be exacerbated by movement.
- Osteonecrosis: Also known as avascular necrosis, this condition involves the death of bone tissue due to a lack of blood supply. It can cause severe knee pain that worsens with weight-bearing activities and requires early diagnosis to prevent further damage.
Rare Diagnoses
- Pigmented Villonodular Synovitis (PVNS): A rare condition characterized by the growth of benign tumors in the synovium of the knee joint, leading to chronic pain, swelling, and stiffness.
- Synovial Chondromatosis: A rare condition where cartilage grows in the synovium of the joint, leading to pain, swelling, and decreased range of motion.
- Knee Tumors: Both benign and malignant tumors can occur in the knee, causing pain, swelling, and other symptoms. These are rare but important to consider in the differential diagnosis.