Knee joints are a complex configuration of multiple ligaments, tendons, bursa, cartilage and bones. When disease or injury impacts these components, swelling may occur to protect the joint as it tries to repair itself. If you have a swollen knee, it may be anything from a mild strain or sprain to a more serious issue like a knee fracture. Here are the possible causes of a swollen knee and when you should see a knee specialist.

Sprains and Strains

Knee sprains occur when ligaments in the knee are torn, stretched or damaged. Knee strains are when the tendons or muscles connected to the knee joint are injured. Knee sprains and strains usually occur from twisting or overexerting the knee. Both can be mild to severe, and all may cause some inflammation and swelling. If swelling continues to get worse after 48 hours, you should see a doctor.

Knee Bursitis

The bursae in the knee can be irritated from overuse or injury, causing one or more bursae to swell. Bursitis can be painful but may go away on its own over time. If the area becomes inflamed or you have a fever with your bursitis swelling and pain, you may have an infection and need antibiotics. Rest and anti-inflammatory medications can help relieve bursitis symptoms, but if it does not improve, you may need to see a doctor.

Knee Fractures

The knee joint has four bones that can be fractured – the tibia, fibula, femur and patella (knee cap). Swelling will occur if one of your knee bones is fractured. When there is a fractured bone, the swelling is likely to be combined with bruising and sharp pain, along with possible deformity of the knee. All knee fractures should be diagnosed and treated by a doctor.


Arthritis in the knee is very common and some people may notice swelling around the knees. Anti-inflammatory medications and other treatments can help control arthritis symptoms – while it is not an emergency, seeing a knee specialist like Dr. Steven Struhl can provide you with arthritis treatments for the knee to give you pain relief.

If you have a swollen knee with ongoing pain or lost mobility, you should see a knee specialist. Contact the Shoulders & Knees office of Steven Struhl, MD in NYC to schedule a knee exam and consultation.