Neurological and neuropsychological correlates of Klippel-Feil syndrome

Background: Klippel-Feil syndrome is a rare congenital malformation caused by fusions of cervical vertebrae. In 50% of these patients, a triad of short neck, limited neck motion, and low posterior hairline characterizes the clinical presentation. In KFS, neurological deficits are common due to cervical canal stenosis and other deformities involving basicranial structures. Other congenital anomalies are also associated with the syndrome. Case presentation: Our case describes a particular case of KFS, showing a disconnection between a severe involvement of the cervical-occipital structures indicated by magnetic resonance imaging and a mild clinical presentation. Moreover, a slight visual-spatial deficit was found in neuropsychological tests. No prior association between KFS and visuospatial impairment has been reported. Discussion and conclusions: GDF6, a gene associated with KFS, plays a role in retinotectal mapping, which organizes visual stimuli in the brain. Early neurodevelopment abnormalities, such as atlanto-occipital anomalies in KFS, might affect related brain structures, which could explain the patient’s impaired visuospatial function. In addition, compensatory neuroplasticity underscores how the brain may adapt to congenital defects, even severe ones.