Novel Method for Diagnosing Lateral Patellar Compression Syndrome Using X-ray: a Retrospective Case-Control Study

This study evaluates whether the patellar axial radiograph of lateral patellar curvature angle （LPCA）with knee flexion at 30 ° can be used as a new diagnostic surrogate of lateral patellar compression syndrome（LPCS）. We believe that the new index LPCA has high sensitivity and specificity in initial diagnosis of LPCS using axial patellar radiograph with knee flexion at 30 ° , and has high application value.