Fig. 2From: Comparison of loss of correction between PSO and VCD technique in treating thoracolumbar kyphosis secondary to ankylosing spondylitis, a minimum 2 years follow-upA 37-year-old male patient with thoracolumbar kyphosis secondary to ankylosing spondylitis. a Preoperative standing lateral radiograph. b Immediately after surgery with pedicle subtraction osteotomy (PSO) technique. c Lateral radiograph taken 26 months after surgery. AIL angle of instrumented levels, DIDW the sum of distal non-fused intervertebral disc wedging, GK global kyphosis, KPNS kyphotic angle of proximal non-fused segment involved in the global kyphosis, LL lumbar lordosis, OA osteotomized vertebra angle, PJA proximal junctional angle, SVA sagittal vertical axis, HP hilus pulmonis, CG the center of gravityBack to article page