Deformity Surgery Principles: The epidemiology of adult spinal deformity and the aging population -- Classification scheme for scoliosis -- Indications for surgery -- Sagittal balance -- Lumbopelvic parameters -- Importance of the fractional curve -- Importance of the fractional curve -- Radiation safety -- Impact of MIS surgery on costs -- Percutaneous Segmental Fixation:  Fluoroscopic techniques -- Image guidance -- Nuances of thoracolumbar screw placement -- Rod contouring, passage, and connection -- Percutaneous pelvic screw fixation.- Managing osteoporotic bone.- Use of cement in MIS deformity surgery -- Posterior Approaches: Interbody cage options -- Multi-level TLIF for spinal deformity -- Expandable cages for thoracic spinal deformity -- Expandable cages for lumbar spinal deformity -- Lumbar endoscopic fusion -- Osteotomy techniques -- Lateral Approaches: Thoracoscopic approaches -- Role of neuromonitoring -- Single incision approach to the lumbar spine -- Dual incision approach to the lumbar spine -- Which side to approach from?- Stand-alone lateral surgery for deformity -- Thoracic interbody surgery.-Complications of the lateral approach -- Dealing with the Lumbo-Pelvic Junction: Mini-open ALIF for fusing the lumbosacral junction -- Trans-sacral interbody fusion as an adjunct to anchoring constructs at the lumbosacral junction -- Minimally invasive sacroiliac joint fusion -- Achieving Intersegmental Arthodesis: Bone graft extenders.-Minimally invasive Wiltse approach posterolateral fusion -- Facet joint fusion -- Future Directions.