Exploring the role of frailty and sarcopenia in predicting postoperative regret and satisfaction following adult spinal deformity surgery.

Abstract

To assess whether preoperative frailty and muscle composition are associated with postoperative satisfaction and decisional regret after adult spinal deformity surgery (ASD). We evaluated 2-year postoperative regret and satisfaction after complex spine surgery in relation to preoperative frailty (mFI-11, CCI), muscle fat infiltration (MFI), skeletal muscle index (SMI) and its subcomponents, and vertebral bone quality (VBQ). Outcomes were measured using the Decisional Regret Scale (DRS) and reverse-coded, 0-100-scaled SRS-22 item 22. Associations were assessed using univariate linear regression and Pearson correlation. No variables met the p < 0.10 threshold for multivariate modeling. The cohort included 112 patients (mean age 63.3 years, 66% female, BMI 29.8 kg/m²). Mean DRS and satisfaction scores were 17.6 and 16.7 (0-100). Higher ESMI trended toward lower regret on DRS Q1 (β = - 0.11, p = 0.05), and higher MFI toward greater disagreement on Q2 (β = 0.20, p = 0.07), with corresponding correlations of r = - 0.27 and r = 0.26 (p = 0.05). No significant associations were observed for composite DRS, satisfaction, or other items. Although no significant associations with overall regret or satisfaction were found, item-level trends in erector spinae mass and muscle fat infiltration suggest a possible link between paraspinal muscle health and how patients assess their decisions after surgery. As a pilot study, these findings provide an early foundation for incorporating muscle composition into preoperative counseling and planning. Larger cohorts are needed to determine whether these markers inform satisfaction and regret after ASD surgery.