Comparison of Patient-Reported Outcomes and Return to Activity Following 1- and 2-level Anterior Cervical Discectomy and Fusion Using a Novel Definition of Cervical Muscle Health
Research Fellow Hospital for Special Surgery Hospital for Special Surgery
Introduction: There is currently no definition of cervical muscle health that incorporates all major cervical muscle groups. We sought to incorporate all major cervical muscle groups into a comprehensive definition of muscle health based on Global Rating of Change (GRC) improvement at > 6 months postoperative. We hypothesized that patients with good muscle health according to our definition will have superior postoperative patient-reported outcomes (PROMs) and quicker return to function after 1- and 2-level anterior cervical discectomy and fusion (ACDF).
Methods: Patients undergoing primary 1- and 2-level ACDFs with minimum 6-months follow-up were included in this retrospective cohort study. Separate logistic regression models for males and females were used to generate receiver operating characteristic (ROC) curves to predict GRC improvement at > 6 months postoperative, accounting for cross sectional areas (CSA) normalized to height-squared of deep flexors (DF), deep extensors (DE), superficial extensors (SE), and sternocleidomastoid (SCM) at C2C3, and DF, DE, SE, SCM, trapezius, and levator scapulae at C5C6. Good and bad muscle health cohorts were determined by the gender-specific cut-off point that optimized sensitivity and 1-specificity. We compared PROMs (neck disability index [NDI], visual analog scale [VAS] for neck and arm pain), PROMs minimal clinically important difference (MCID), and return to activities (RTA) (return to driving, work, and days to discontinue opioids) for gender-specific good and bad muscle health cohorts at time points 2 weeks, 6 weeks, 12 weeks, 6 months, 1 year, 2 year.
Results: 153 patients were included for analysis. Area under the curve (AUC) for ROC-male was 0.78 and AUC for ROC-female was 0.72, indicating fair discrimination. There was no difference between good and bad muscle health cohorts regarding preoperative or postoperative VAS neck or arm at any time point. Poor muscle health cohort had a higher 6 week NDI (p = 0.046). There were no differences in PROMs MCID or days to return to driving, work, and to discontinue opioids.
Conclusion : A comprehensive definition of cervical muscle health using ROC curves predicting for GRC improvement may provide a more granular perspective of cervical muscle health. Further investigation is required.