Systematic Review: Physiological and Functional Impairments after Anterior Cervical Discectomy and Fusion

Objective(s): To extract information from studies with high levels of evidence on the incidence, timeline, physiological characteristics, functional changes, and possible causes of dysphagia after anterior cervical discectomy and fusion (ACDF).

Data Sources: The literature search was conducted using various search strings for cross-referencing in Cochrane, Ovid, and PubMed. Research studies spanning 20 years on swallowing issues related to ACDF were obtained, and 380 journal articles were identified by filtering out non-English publications or studies involving pediatric populations.

Study Selection: The authors screened research studies using pre-determined criteria to reach a consensus on which studies to include and exclude.

Data Extraction: After further screening, 372 articles were eliminated due to duplicate studies, content unrelated to oral feeding, ACDF or dysphagia, poorly defined swallowing issues, unclear assessment methodology or diagnostic tools, use of only patient self-reports or quality of life surveys, and case studies or secondary studies. Ultimately, 8 articles were selected for the final analysis.

Data Synthesis: Dysphagia is often caused by soft tissue swelling resulting from retraction pressure on the esophagus, pharyngeal weakness, surgical hardware or bone graft displacement, esophageal perforation, and retropharyngeal abscesses. Physiological findings from videofluoroscopic swallow studies (VFSS) and fiberoptic endoscopic evaluation of swallowing (FEES) indicate posterior pharyngeal weakness, decreased hyoid excursion, reduced cricopharyngeal and upper esophageal opening, vocal fold immobility, pharyngeal residues, and spiration. Most patients showed improved swallowing function within the first few months, while some continued to experience long-lasting swallowing impairments.

Conclusions: Research studies emphasize early screening for post-ACDF dysphagia to avoid secondary complications and prolonged hospitalizations. Adequate instrumental examinations of swallowing are crucial in assessing and managing swallowing impairments postoperatively. Literature also suggests perioperative rehabilitation therapy to reduce the severity of postoperative dysphagia.

Author(s) Disclosures: Fang-Ling Lu, Ph.D.: Salaried full-time faculty at UT Health San Antonio. Nonfinancial- None to report.

Tabitha H. Kao, M.S.: Salaried part-time research fellow and doctoral student at MGH Institute of Health Professions. Nonfinancial- None to report.