Intrarater reliability of measuring the patella position by ultrasonography in weight-bearing condition.

Only ten asymptomatic adults were tested, so the result does not show reliability in patients with knee pain or other conditions. Only one physical therapist performed the measurements, so the study does not show that different therapists can get the same result. The method measured static patella position only, so it does not show dynamic patella tracking during movement. Quadriceps contraction was not directly measured, so the level of muscle contraction in each trial is uncertain. The paper reports reliability of a measurement method, not diagnostic accuracy or clinical benefit. The discussion reports an ICC of 0.83 at 20 degrees, while the results table reports 0.86.

Do not read this as proof that ultrasound can diagnose patellofemoral pain or guide treatment. The paper tested one rater's static measurement in asymptomatic adults, not patients, not dynamic tracking, and not diagnostic accuracy.