Knee Flexion Restriction Due to Patella Alta

Patella alta refers to an abnormally high position of the kneecap relative to the femur. Diagnosis is confirmed through lateral knee X-rays by measuring the Insall-Salvati ratio. If the ratio of the patellar tendon length to the patellar height is greater than 1.2, it confirms the kneecap sits too high, causing delayed engagement in the trochlear groove and subsequent flexion restriction.

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