Background: Horner syndrome (HS), is rare postoperative complications, after Anterior Cervical Discectomy and Fusion (ACDF). This study aims to describe the incidence, patients and surgical approach, outcomes and possible predilection factors for occurrence of Horner syndrome after anterior approach for cervical discectomy.

Methods: A retrospective study for 820 patients who had single or successive two ACDF for cervical DDD using PolyEtherEtherKetone (PEEK) cages between 2016 and 2019. Charts were reviewed to identify patients with postoperative occurrence of Horner syndrome for follow up period 12 months. Outcome for ptosis being the most important factor, was classified according to marginal reflex distance.

Results: 40 patients who had Postoperative HS after ACDF from 820 patients (4.8%), 67% had single level discectomy, most frequent level was C5-6, average age 47 years, 55% males, 33% smokers and 20% diabetics. Radiculopathy was more frequent, when anterior plate fixation system was used incidence of Horner was higher (60%). Improvement or complete resolution occurred in 90% of cases.

Conclusions: Using anterior plating system, and male gender increase the risk of Horner`s syndrome. We find HS is a temporary clinical manifestation in most of cases, which managed conservatively.