Significance of long corrective fusion to the ilium for physical function in patients with adult spinal deformity

Background: We aimed to investigate the impact of long corrective fusion to the ilium on the physical function in elderly patients with adult spinal deformity and its correlation with spinopelvic parameters and health-related quality of life outcomes. Methods: We included 60 female patients who underwent long corrective fusion from T9 or T10 to the pelvis for adult spinal deformities (mean age of 69.8 years, range 55-78 years). The radiographic pa-rameters, health-related quality of life outcomes using the Scoliosis Research Society Outcome Instrument-22 and physical function assessments were reviewed preoperatively and at 1-year postoperatively. Results: All spinopelvic parameters, except for thoracolumbar kyphosis, and all domains of the Scoliosis Research Society Outcome Instrument-22 significantly improved at 1-year postoperatively (p < 0.0001). Physical function results, including those for one-leg standing time, timed up-and-go test, and 6-min walk tests, significantly improved at 1-year postoperatively (p < 0.005). Based on forward stepwise multivariate logistic regression, the predicted timed up-and-go test and 6-min walk test outcomes at 1-year postoperatively were as follows: timed up-and-go test, 7.8 + 0.47 x preoperative timed up-and-go test -0.21 x 1-year postoperative grasping power +0.015 x 1-year postoperative C1 sagittal vertical axis (R2 = 0.6209, p < 0.0001); 6-min walk test, 309.2-9.1 x body mass index + 11.6 x 1-year postoperative grasping power + 3.3 x 1-year postoperative thoracolumbar kyphosis -0.59 x 1-year postoperative C1 sagittal vertical axis (R2 = 0.4409, p < 0.0001). Conclusions: Corrective long fusion surgery for adult spinal deformity in normalizing sagittal alignment improves trunk balance and gait performance. Postoperative physical function depends on the preop-erative physical performance status and skeletal muscle status; thus, preoperative interventions for improved physical function are recommended. (c) 2020 Published by Elsevier B.V. on behalf of The Japanese Orthopaedic Association.