The C2-tongue connection: anatomically tasteful but often forgotten

Abstract

Statement We present a case of post-operative numbness of the tongue after surgical resection of an intradural C2 meningioma. This case report is the first to describe an ipsilateral numbness of the tongue after manipulation of the C2 nerve root in spinal meningioma surgery. The underlying explanatory anatomy for the clinical symptoms has previously been described in the neck-tongue syndrome. This anatomical relationship is particularly interesting, but also important for spine surgeons performing complex cervical spine procedures. Clinical description A 50-year-old patient was referred to our neurosurgical department with a cerebellopontine angle meningioma. During the diagnostic work-up, a large right-sided intraspinal extramedullary mass at the second cervical level was identified , causing compression of the spinal cord. MRI imaging showed an intraspinal extramedullary retro-corporal mass at the base of the C2 vertebra compatible with a meningioma (Fig. 1). In consultation with the multidisciplinary surgical team, the spinal meningioma at C2 was treated first. The surgery was performed using intra-operative neuromonitoring using somatosensory evoked potentials (SEPP) and motor evoked potentials (MEP) in collaboration with the neurology department. The intradural mass was visualized after a C2 laminectomy and durotomy. The mass was totally resected (Simpson grade II). The C2 nerve root was not sacrificed, nor the dentate ligament was cut. SEPP and MEP signals remained uninterrupted during the procedure. Post-operatively the patient had post-operative nausea and vomiting (PONV) and complained of right-sided numbness of the tongue, auricular pain and irritation of the skin on and behind the ear. The rest of the clinical examination was completely normal. The patient was able to leave the hospital after 1 week. Histopathological examination confirmed a WHO-grade 1 meningioma. One month after the surgery, the patient was seen at the neurosurgical outpatient clinic. The numbness of the tongue and auricular pain improved significantly. The residual symptoms consisted of some numbness posteriorly to the ear on her head. The patient was informed that further improvement could be expected over time. A post-operative MRI scan was performed to confirm the extent of the resection. This MRI scan showed no residual meningioma (Fig. 1). Discussion and conclusion We hypothesized that the symptoms could be explained by the anatomical relation between the hypoglossal nerve and the cervical nerve roots. This anatomical correlation was initially mentioned in the literature as neck-tongue syndrome. The neck-tongue syndrome is a rare condition characterized by pain in the upper cervical/occipital areas associated with ipsilateral glossal paresthesia, mostly after sudden neck movement [1]. Anatomical studies have illustrated the association between the cervical plexus and the hypoglos-sal nerve. Lance and Anthony were the first to describe the anatomical correlation between the hypoglossal nerve and * Raymaekers Vincent