Diagnostic accuracy of the resisted external derotation test for gluteal tendinopathy and central sensitization: A musculoskeletal ultrasound validation study using a novel phenotypic classification scale

This study evaluates the diagnostic accuracy of the Resisted External De-rotation test for identifying gluteal tendinopathy in individuals with lateral hip pain, using musculoskeletal ultrasound as the reference standard. It also examines how central sensitization influences the accuracy of this clinical test. Central sensitization is assessed using the Central Sensitization Inventory (CSI) and the Pressure Pain Threshold (PPT) test. A new phenotypic classification scale is proposed to distinguish true tendon pathology from pain driven mainly by central mechanisms. The study aims to reduce misdiagnosis, explain false-positive test results, and improve diagnostic precision. Findings are expected to support more personalized and mechanism-based management of greater trochanteric pain syndrome.