Which of the following is a hallmark feature of patellofemoral pain syndrome?

• A. Crepitus and lateral tracking of the patella
• B. Pain with plantarflexion
• C. Swelling of the tibial tubercle
• D. Pain with ankle inversion

Answer: (C)

Patellofemoral pain syndrome shows anterior knee pain around the patellofemoral joint, often worsened by activities that bend the knee deeply—stairs, squatting, running, or sitting with the knee flexed for long periods. A key sign is crepitus, a grinding or crackling sensation under or around the patella when the knee is moved, reflecting rough movement at the patellofemoral joint. Lateral tracking of the patella can also occur, where the kneecap drifts slightly to the outside during bending, contributing to pain and altered knee mechanics.

Swelling at the tibial tubercle points to a different condition (like Osgood-Schlatter disease), not typical PFPS. Pain with plantarflexion involves the ankle/foot region rather than the knee joint itself, and pain with ankle inversion is clearly an ankle sprain scenario. So the hallmark feature to look for with patellofemoral pain syndrome is anterior knee pain with patellofemoral crepitus and potential maltracking of the patella.