Differential Diagnosis for Anterior Medial Knee Pain
Single Most Likely Diagnosis
- Patellofemoral Pain Syndrome (PFPS): This is the most common cause of anterior knee pain, especially in young, active individuals. It is characterized by pain around or behind the patella, usually exacerbated by activities that load the patellofemoral joint, such as climbing stairs, squatting, or jumping.
Other Likely Diagnoses
- Medial Meniscal Tear: Tears in the medial meniscus can cause pain in the anterior medial aspect of the knee, especially with twisting or bending movements.
- Medial Collateral Ligament (MCL) Sprain: An injury to the MCL can result in pain along the medial (inner) aspect of the knee, including the anterior medial region.
- Pes Anserine Bursitis: Inflammation of the pes anserine bursa, located on the medial aspect of the knee, can cause pain in this area, particularly in individuals with knee osteoarthritis or those who are overweight.
Do Not Miss Diagnoses
- Osteonecrosis of the Knee: Although less common, osteonecrosis (avascular necrosis) of the knee can present with sudden onset of pain, typically in the medial or lateral compartment, and must be considered to avoid delayed diagnosis and potential collapse of the bone.
- Infection (Septic Arthritis): Any infection within the knee joint can cause severe pain, swelling, and decreased range of motion. It is a medical emergency requiring prompt diagnosis and treatment.
- Tumor: Both benign and malignant tumors can occur around the knee and cause pain. While rare, they are critical to diagnose early for appropriate management.
Rare Diagnoses
- Saphenous Nerve Entrapment: Entrapment or irritation of the saphenous nerve can cause pain or numbness in the medial aspect of the knee and leg.
- Osgood-Schlatter Disease: Typically seen in adolescents, this condition involves inflammation of the patellar tendon at its insertion on the tibia, leading to anterior knee pain.
- Synovial Chondromatosis: A rare condition characterized by the growth of cartilage in the synovium of the joint, which can cause pain, swelling, and decreased mobility of the knee.