Sex-Specific Influence of Preoperative Musculoskeletal Characteristics on Postoperative Outcomes in Lumbar Spinal Surgery: A Prospective Cohort Study

Lumbar spinal stenosis often necessitates surgical intervention, with preoperative musculoskeletal health significantly influencing postoperative outcomes. This prospective cohort study investigates the sex-specific impact of preoperative musculoskeletal characteristics on postoperative leg pain in elderly patients undergoing lumbar surgery. This study is a secondary analysis of data from the patient-reported outcome measure stratification after surgery for lumbar spinal stenosis with sarcopenia : A prospective cohort study of surgically treated spinal stenosis (STRATEGY-SS) cohort, which recruited lumbar spinal stenosis patients from a tertiary care center between March 2019 and February 2021. Preoperative assessments included evaluations for sarcopenia, muscle mass, grip strength, and physical performance. Patient-reported outcomes for back and leg pain were assessed preoperatively and 1 year postoperatively. Statistical analyses included t-tests, χ2 tests, receiver operating characteristic analysis, and linear regression path analysis. Significant sex differences were observed in preoperative characteristics. In male patients, no preoperative variables significantly predicted postoperative pain severity. However, in female patients, arm and calf circumferences were significantly associated with 1-year postoperative leg pain. Receiver operating characteristic analysis identified several preoperative predictors of postoperative leg pain in females, with arm circumference showing notable predictive power. Linear regression suggested that smaller arm circumference indirectly contributed to more severe postoperative leg pain through longer hospital stays. These findings highlight the need for sex-specific preoperative assessments to improve surgical outcomes, suggesting that targeted preoperative interventions to enhance musculoskeletal health could benefit female patients undergoing lumbar surgery.