A Newer Way of Determining LIV in AIS Patients: Rotation of the Touched Vertebrae

• Published in: Spine (Philadelphia, Pa. 1976) Pa. 1976), 2022-09, Vol.47 (18), p.1321-1327
• Main Authors: Sarwahi, Vishal, Hasan, Sayyida, Wendolowski, Stephen, Visahan, Keshin, Atlas, Aaron, Galina, Jesse, Lo, Yungtai, Amaral, Terry, Rao, Himanshu, Thornhill, Beverly
• Format: Article
• Language: English
• ISSN: 0362-2436; 1528-1159
• DOI: 10.1097/BRS.0000000000004378

STUDY DESIGNA retrospective review. OBJECTIVEThe objective of this study was to determine whether fusing to touched vertebra (TV) on prone x-rays (XRs) with minimal rotation (Gd 0/1) allow for shorter fusion with optimal correction. SUMMARY OF BACKGROUNDPrevious studies have shown risk of "adding on" when TV is not selected as lowest instrumented vertebra (LIV). Fusion proximal to TV leads to suboptimal results but fusing to TV on standing XRs can result in longer fusions. On lying down XRs, TV moves proximally, and its rotation decreases by a grade. METHODSTV patients with minimal rotation were selected on prone (TVP) or standing XRs (TVS). Patients fused to rotated (Gd 2+) TV on standing or prone XRs were considered touched vertebra rotated (TVR). In the non-TV (NTV) group, LIV was fused proximal to TV. Disk wedging ≥5° determined risk of "adding-on." To compare patients fused to minimally rotated TV, to those that were not, patients in group A (TVP + TVS) were compared with group B (TVR + NTV).In part II: TVP, TVS, TVR, and NTV patients were compared. Subanalysis compared levels saved as the difference between predicted and real LIV in TVP and TVS patients. Another subanalysis was carried out for Lenke 1+2 and Lenke 3, 4, 5.In part III: XRs of nonoperative adolescents idiopathic scoliosis patients with Cobb