Prospective Evaluation of Complex Adult Spinal Deformity (CAD) Treated With Minimally Invasive Surgery

Inclusion Criteria: 1. \>18 years of age at the time of treatment 2. Diagnosis of adult congenital, degenerative, idiopathic, neuromuscular, inflammatory or iatrogenic spinal deformity 3. EOS full body or standing 36" AP \& Lateral images of entire spine 4. Surgery to be schedule to take place within 6 months (otherwise PROMs/Radiographic images to be recollected) AND Either: 5. One of the following Radiographic criteria: 1. PI-LL ≥ 25 degrees 2. Thoracolumbar/lumbar scoliosis ≥ 20 degrees 3. SVA \>10cm 4. PT \> 30 OR 6. One of the Following Procedural criteria: 1. Surgery to include \> 3 levels percutaneous posterior spinal instrumentation or 3 level stand-alone interbody. (Levels = vertebra (i.e. percutaneous screws at L2, L3, L4 would be eligible for posterior instrumentation and/or L3-L4, L4-L5 would be eligible as stand-alone for interbodies) 2. Posterior UIV and LIV must be placed percutaneously 3. Single-position surgery ≥ 3 levels fused (Levels=vertebra; S1 is counted as a level; S2 \&/or pelvis/ilium is not) 4. Staged ≥ 3 levels fused with percutaneous pedicle screws 5. 3 column osteotomy with percutaneous fixation 6. ACR incorporating open or percutaneous fixation as long as UIV and LIV are percutaneous screws Exclusion Criteria: 1. Deformity due to acute trauma 2. Active spine tumor or infection 3. Patient is unwilling or unable to complete questionnaires 4. Women who are pregnant 5. Prisoners 6. Open Posterior spinal fusion is planned (Open Anterior, i.e. ALIF, is acceptable)