Yoshiki Asai,1 Shunji Tsutsui,1 Noriko Yoshimura,2 Hiroshi Hashizume,1 Toshiko Iidaka,2 Chiaki Horii,2 Hiroshi Kawaguchi,3 Kozo Nakamura,4 Sakae Tanaka,5 Munehito Yoshida,1 Hiroshi Yamada1 1Department of Orthopedic Surgery, Wakayama Medical University, Wakayama, Japan; 2Department of Preventive Medicine for Locomotive Organ Disorders, 22nd Century Medical and Research Center, Faculty of Medicine, The University of Tokyo, Tokyo, Japan; 3Department of Orthopedic Surgery, Tokyo Neurological Center, Tokyo, Japan; 4Department of Orthopedic Surgery, Towa Hospital, Tokyo, Japan; 5Department of Orthopedic Surgery, Faculty of Medicine, The University of Tokyo, Tokyo, JapanCorrespondence: Shunji TsutsuiDepartment of Orthopedic Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8510, JapanTel +81-73-441-0645Fax +81-73-448-3008Email stsutsui1116@gmail.comPurpose: The demand for surgical correction in elderly patients with adult spinal deformity (ASD) has recently increased with the growth of the aging population. Age-related changes in spinopelvic sagittal alignment have been recently reported; thus, sagittal realignment should consider age-related changes. This study aimed to investigate the relationship between age-specific sagittal spinopelvic radiographic parameters and low back pain (LBP) to support the establishment of age-specific realignment targets for patients with ASD.Materials and Methods: A population-based cohort consisting of 1461 subjects (466 men and 995 women) was used. The participants were divided into five groups based on their age: (1) younger than 50 years, (2) 50– 59 years, (3) 60– 69 years, (4) 70– 79 years, and (5) 80 years and older. Standing lateral whole-spine radiographs were assessed to measure lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), and sagittal vertical axis (SVA). In addition, all participants were asked if they had LBP or not, using the following question: “Have you experienced LBP on most days during the past month and/or now?”.Results: The crucial parameter associated with LBP was the mismatch between PI and LL (PI-LL). The mean values of all the radiographic parameters increased with age. PI-LL and PT reached 11.5° and 25.6°, respectively, for women without LBP in the super-aged group (age > 80 years), which did not lie in the range of optimal values reported in the previous literature.Conclusion: A new optimal age-related target may be needed for the management of patients with ASD.Keywords: adult spinal deformity, spinopelvic sagittal alignment, low back pain, population-based cohort
