Rethinking sagittal alignment: the value of evaluating spinal shape in conjunction with T4-L1 pelvic angle measurement to prevent proximal junctional failure.
OBJECTIVE The T4-L1 pelvic angle (T4-L1PA) has been proposed as a novel alignment target associated with mechanical complications in long-segment adult spinal deformity (ASD) surgery. However, its relationship to proximal junctional failure (PJF) and its relevance in shorter thoracolumbar constructs remain unclear. The...