Differential Diagnosis for 15-year-old Female with Pain Superior to Patella and Audible Click during Knee Extension
- Single Most Likely Diagnosis
- Patellofemoral Pain Syndrome (PFPS): This condition is characterized by pain around or behind the patella, often associated with activities that put stress on the knee, like climbing stairs, squatting, or jumping. The audible click during knee extension could be related to the patella tracking abnormally, which is common in PFPS. The age and presentation of the patient make this a highly plausible diagnosis.
- Other Likely Diagnoses
- Chondromalacia Patellae: This condition involves the softening of the cartilage on the underside of the kneecap, leading to knee pain and tenderness. It's common in adolescents and can cause an audible click or grinding sensation during knee movement.
- Patellar Subluxation: This is a condition where the patella partially dislocates out of its normal position, which can cause pain and an audible click as the patella moves back into place during knee extension.
- Do Not Miss Diagnoses
- Osteosarcoma or Other Bone Tumors: Although rare, bone tumors can present with pain and mechanical symptoms like clicking. It's crucial to consider these in the differential diagnosis to ensure timely diagnosis and treatment if present.
- Septic Arthritis: This is an infection within a joint, which can cause severe pain, swelling, and decreased range of motion. While less likely given the description, it's a critical diagnosis not to miss due to its potential for rapid joint destruction and systemic infection.
- Rare Diagnoses
- Synovial Plica Syndrome: This condition involves inflammation of the synovial folds within the knee joint, which can cause knee pain and mechanical symptoms like clicking or snapping.
- Sinding-Larsen-Johansson Syndrome: This is a rare condition that affects the patellar tendon at its insertion on the tibia, causing pain and swelling just below the kneecap. It's more common in adolescent athletes and could potentially cause an audible click during knee extension, although this is less typical.