Assessing the association between revision anterior cervical spine surgery for adjacent segment disease and postoperative dysphagia.

Abstract

Revision surgery is a known risk factor for postoperative dysphagia. This study aimed to assess the association of revision surgeries indicated to treat adjacent segment disease (ASD) with pre- and postoperative dysphagia rates. A prospectively collected quality registry for anterior cervical spine surgery was retrospectively reviewed. Eating Assessment Tool-10 (EAT-10) dysphagia questionnaire responses were collected at baseline and at 1, 3, and 12 months postoperatively, using scores ≥ 3 to represent dysphagia. Revision surgeries indicated for ASD were compared against primary surgeries, and univariate analysis assessed differences in patient demographics, surgical information, and patient-reported outcome measures. Fixed-effects logistic regressions were performed to assess the independent impact of ASD on postoperative dysphagia and to identify risk factors within revision surgery. Of the 1713 patients in the cervical spine registry meeting the inclusion criteria, 279 (16.3%) had preoperative ASD while 1434 (83.7%) were primary surgeries. ASD was associated with a higher incidence of dysphagia at 1 (65% vs 57%, p = 0.024), 3 (43% vs 30%, p < 0.001), and 12 months (35% vs 26%, p = 0.018), but not at baseline (15% vs 12%, p = 0.11). Among patients without baseline dysphagia, patients with ASD were significantly more likely to report new dysphagia at 3 months (38% vs 26%, p < 0.001) but not at 1 (59% vs 54%, p = 0.2) or 12 months (26% vs 21%, p = 0.2). Among patients with baseline dysphagia, the average EAT-10 score improved from baseline to 12 months postoperatively, but patients with ASD experienced significantly less improvement (-1.414 [SD 8.399] vs -5.793 [SD 9.217], p = 0.011). In the multivariable analyses of all patients, ASD was an independent predictor of dysphagia at 3 months (OR 1.11, p < 0.001) but not at 1 (OR 1.03, p = 0.4) or 12 months (OR 1.05, p = 0.2). Among patients with ASD, 3-month dysphagia was independently predicted by baseline dysphagia (OR 1.42, p < 0.001), C3-4 exposure (OR 1.27, p = 0.004), and re-exposure of prior levels (OR 1.16, p = 0.024), while an otolaryngologist-assisted approach predicted a lower risk (OR 0.77, p = 0.022). ASD did not significantly impact baseline dysphagia rates, but revision surgery for ASD was a significant independent risk factor for delayed recovery from initial postoperative dysphagia beyond 3 months following anterior cervical spine surgery. Exposure-related variables further stratified risk within ASD revision surgery. Preoperative patient counseling should manage patient expectations accordingly.