Hypoglossal nerve palsy following spine surgery in Klippel-Feil syndrome patient

INTRODUCTION Hypoglossal nerve palsy resulting from cervical spine surgery is exceedingly rare, with literature suggesting overall rates as low as 0.01% and institutional rates ranging from 0% to 1.28%. Still, the morbidity for patients is significant and can include symptoms such as dysphagia, dysarthria, and tongue weakness. Previous reports suggest patient positioning, retraction of the hypoglossal nerve or other anterior structures of the neck, or nerve compression from tracheal intubation may cause this complication. Klippel-Feil Syndrome (KFS) is a congenital disorder characterized by auto fusion of cervical vertebrae and has been associated with numerous orthopedic abnormalities including scoliosis and Sprengel deformity. KFS may also be associated with developmental abnormalities in other organ systems, which could lead to anatomical variations in structures such as nerves and blood vessels. We present a case of a 60-year-old male (Patient Z) with KFS who developed dysphagia, dysarthria, tongue deformation and flaccidity immediately following C3-C6 anterior cervical discectomy and fusion (ACDF) and was subsequently diagnosed with left-sided hypoglossal nerve palsy. The patient has given their informed consent for the clinical information and images presented. Institutional Review Board (IRB) ethical approval was not required for this case report. CASE REPORT