Fig. 1

Intraoperative Measurement of Pelvic Incidence (PI) and Lumbar Lordosis (LL): Outlining the steps and techniques used during surgery. Image 1: Initial C-ARM Position: Positioning at the level of the femoral head and sacrum for the first shot to obtain baseline measurements. Image 2: Adjusted C-ARM Position: Moving the C-ARM caudally for a comprehensive lumbar spine evaluation. Images 3 & 4: iOS Measure App Use: Demonstrating the application setup and the angle measurement process