Fig. 6.

A 52-year-old male who has severe sagittal imbalance of 21 cm and fixed hip contracture of 20 degree despite prior spinal instrumentation and fusion surgeries. Revision PSSIF at T9–Pelvis with 2nd PSO at L4 showed good restoration of lumbar lordosis from 42.80 to 59.00. His preoperative PI was 69.50. However, his SVA in 3 months is 12.0 cm. Increase in thoracic kyphosis of 90 and flexion contracture took out the advantage of restoration of lumbar lordosis. Significant improvement in sagittal vertical axis in 3 years to 7.1 cm came after relief of hip flexion contracture with physical therapy. SVA : sagittal vertical axis, PI : pelvic incidence, SS : sacral slope, LL : lumbar lordosis, TK : thoracic kyphosis, PO : postoperative, PSSIF : posterior spinal segmental instrumentation and fusion, PSO : pedicle subtraction osteotomy, PLIF : posterior lumbar interbody fusion.