Background Skull based neurosurgical cases often require some degree of head rotation during patient positioning to facilitate operative exposure. Extreme head rotation may lead to occlusion of submandibular gland secretions and impaired venous return from the neck, rarely leading to submandibular gland inflammation. Methods An uncomplicated translabyrinthine resection of a vestibular schwannoma was undertaken. Results Severe submandibular gland inflammation and impaired venous return opposite the site of translabyrinthine vestibular schwannoma resection occurred in the post-operative period. This led to upper brachial plexopathy and Horner syndrome. Conclusions We present the first known cases of submandibular gland inflammation and hemorrhage resulting in brachial plexopathy and Horner syndrome opposite the site of tumor resection. This case underscores the importance of adequate and safe patient positioning in skull based neurosurgical procedures. © 2014 The Authors.