Eccentric step-down is better for ruling in or ruling out PFPS?

• A. Ruling in
• B. Ruling out
• C. Both
• D. Neither

Answer: (A)

The main idea here is using a test with high specificity to confirm a diagnosis when positive. The eccentric step-down stresses the patellofemoral joint during the controlled descent, loading the patella eccentrically as the knee flexes. In patellofemoral pain syndrome, this contact and tracking stress often reproduces the characteristic anterior knee pain. Because a positive result is relatively specific for PFPS, it meaningfully increases the probability that PFPS is present, making it helpful for ruling in the diagnosis. A negative result, however, doesn’t reliably exclude PFPS, since sensitivity may be limited and other factors can influence the test outcome. So, this maneuver is best for ruling in PFPS when it provokes familiar pain.