Fig. 2From: Coronal and sagittal balance in Lenke 5 AIS patients following posterior fusion: important role of the lowest instrument vertebrae selectionThe pre-, 3-year post- and 6-year post-operative X rays of a Lenke 5 AIS patient with initial and final sagittal imbalance. This patient had main lumbar Cobb angle of 62.0° before surgery and 8.5° at 6 years after surgery with a corrective rate of 86.3%. And coronal balance was always normal. However, she had severe sagittal imbalance preoperatively (SVA = − 90.4 mm, PT = − 4.6° and PI-LL = − 21.9°). At 3 years after surgery, thought the pelvic posture has restored to normal (PT = 6.5°) with a normal PI-LL matching (PI-LL = − 6.9°), however her sagittal imbalance was still exist with a SVA = − 63.5 mm. At final follow-up (6 years), the sagittal imbalance has still not compensated to normal. Fused to L5 has sacrificed most of the sagittal compensatory ability and this should be an important reason for her final sagittal imbalanceBack to article page