Four-level ACDF surgical series 2000-2022: a systematic review of clinical and radiological outcomes and complications.
OBJECTIVE The primary objective of this investigation is to systematically scrutinize extant surgical studies delineating Four-Level Anterior Cervical Discectomy and Fusion (4L ACDF), with a specific emphasis on elucidating reported surgical indications, clinical and radiological outcomes, fusion rates, lordosis correction, and the spectrum of complication rates. METHODS The literature review was conducted in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, employing the MEDLINE (PubMed), Embase, and Scopus databases. This analysis encompasses studies implementing the 4L ACDF procedure, with detailed extraction of pertinent data pertaining to surgical methodologies, types of employed interbody cages, clinical and radiological endpoints, rates of fusion, and the incidence of complications. RESULTS Among the 15 studies satisfying inclusion criteria, a marginal increment in the year 2022 (21.4%) was discerned, with a preponderance of study representation emanating from China (35.7%) and the United States (28.6%). 50% of the studies were single-surgeon studies. Concerning follow-up, studies exhibited variability, with 42.9% concentrating on periods of five years or less, and an equivalent proportion extending beyond this timeframe. Across the amalgamated cohort of 2457 patients, males constituted 51.6%, manifesting a mean age range of 52.2-61.3 years. Indications for surgery included radiculopathy (26.9%) and myelopathy (46.9%), with a predilection for involvement at C3-7 (24.9%). Meta-analysis yielded an overall complication rate of 16.258% (CI 95%: 14.823%-17.772%). Dysphagia (4.563%), haematoma (1.525%), hoarseness (0.205%), C5 palsy (0.176%) were the most prevalent complications of 4L ACDF. Fusion rates ranging from 41.3% to 94% were documented. CONCLUSION The 4L ACDF is commonly performed to address mylopathy and radiculopathy. While the surgery carries a complication rate of around 16%, its effectiveness in achieving bone fusion can vary considerably.