Differential Diagnosis for Medial Knee Pain
- Single most likely diagnosis
- Medial meniscus tear: This is a common cause of medial knee pain, especially in individuals who participate in sports or activities that involve twisting or bending of the knee. The meniscus is a cartilage structure that can be damaged, leading to pain and stiffness in the knee.
- Other Likely diagnoses
- Medial collateral ligament (MCL) sprain: The MCL is a ligament that connects the femur to the tibia and provides stability to the knee. A sprain or tear of the MCL can cause medial knee pain, especially with activities that involve valgus stress (a force that pushes the knee inward).
- Pes anserine bursitis: This is an inflammatory condition that affects the bursa located on the medial aspect of the knee. It can cause pain and swelling in the area, especially with activities that involve bending or twisting of the knee.
- Osteoarthritis: This is a degenerative joint disease that can cause pain and stiffness in the knee, especially in older adults. Medial knee pain is a common symptom of osteoarthritis, especially if the disease is more advanced.
- Do Not Miss diagnoses
- Deep vein thrombosis (DVT): Although less common, DVT can cause medial knee pain, especially if the clot is located in the popliteal vein. This is a potentially life-threatening condition that requires prompt medical attention.
- Septic arthritis: This is a bacterial infection of the joint that can cause severe pain, swelling, and stiffness in the knee. It is a medical emergency that requires prompt treatment with antibiotics.
- Osteonecrosis: This is a condition that occurs when the blood supply to the bone is disrupted, leading to bone death. It can cause medial knee pain, especially if the affected bone is in the medial compartment of the knee.
- Rare diagnoses
- Medial knee tumor: Although rare, tumors such as osteosarcoma or chondrosarcoma can cause medial knee pain. These conditions are often associated with other symptoms such as swelling, redness, and limited range of motion.
- Nerve entrapment: The saphenous nerve or the medial branch of the saphenous nerve can become entrapped, causing medial knee pain. This is a rare condition that can be diagnosed with electromyography (EMG) or nerve conduction studies.
- Infection of the medial knee structures: Infections such as cellulitis or abscesses can cause medial knee pain, especially if they involve the skin, subcutaneous tissue, or deeper structures such as the bursae or tendons.