Differential Diagnosis for Patelloradial Pain in a 14-Year-Old
Single Most Likely Diagnosis
- Patellofemoral Pain Syndrome (PFPS): This condition is the most common cause of knee pain in adolescents, especially in those who are active in sports. It is characterized by pain around or behind the patella, often associated with activities that put stress on the knee, such as jumping, running, or climbing stairs. The pain can be exacerbated by sitting for long periods or going up and down stairs.
Other Likely Diagnoses
- Osgood-Schlatter Disease: A common cause of knee pain in adolescents, particularly during growth spurts. It is characterized by inflammation of the patellar tendon at its insertion on the tibial tubercle, leading to pain, swelling, and tenderness just below the knee.
- Sinding-Larsen-Johansson Syndrome: Similar to Osgood-Schlatter disease but affects the patellar tendon at its origin on the inferior pole of the patella. It causes pain and swelling below the kneecap.
- Medial Plica Syndrome: Irritation of the medial plica, a fold of synovial tissue in the knee, can cause medial knee pain, which might be perceived as patelloradial pain due to the proximity of the structures.
Do Not Miss Diagnoses
- Tumor (e.g., Osteosarcoma): Although rare, bone tumors can present with pain and should always be considered, especially if the pain is persistent, worsening, or accompanied by other systemic symptoms like weight loss or fever.
- Infection (Septic Arthritis or Osteomyelitis): Infections within the joint or bone can cause severe pain, redness, swelling, and warmth. These conditions are medical emergencies requiring prompt diagnosis and treatment.
- Fracture: Stress fractures or acute fractures around the knee can cause significant pain and must be ruled out, especially with a history of trauma.
Rare Diagnoses
- Binding-Larsen Syndrome: A rare condition that affects the iliotibial (IT) band and the lateral aspect of the knee, potentially causing pain that could be mistaken for patelloradial pain.
- Dysplasia of the Patellofemoral Joint: Abnormal development of the patellofemoral joint can lead to pain and instability, though it is less common and often associated with other congenital anomalies.
- Neuroma or Nerve Entrapment: Rarely, nerve entrapment or neuroma formation around the knee can cause pain that might be perceived in the patelloradial area.