Identifying criteria for diagnosis of post-traumatic pain and altered sensation of the maxillary and mandibular branches of the trigeminal nerve: a systematic review

Objective: The aim of the study was to systematically identify criteria used to diagnose patients with trigeminal nerve injury. Study Design: A systematic review of the literature registered in the PROSPERO database. Inclusion criteria were patients diagnosed with nerve injury of the sensory divisions of the maxillary or mandibular branches of the trigeminal nerve, with reported tests and criteria used for diagnosis and persistent pain or unpleasant sensation associated with nerve injury. Results: In total, 28 articles were included. Diagnostic tests included clinical neurosensory tests (89%), thermal quantitative sensory testing (QST; 25%), electromyography (7%), and patient interview (14%). Neuropathic pain was assessed by using the visual analogue scale (39%); patient use of neuropathic medication (7%); questionnaires, including McGill and PainDETECT (21%). Functional impact was assessed in 14% and psychological impact in 7% of articles. Methodology in performing clinical neurosensory tests, application of diagnostic terms and diagnostic grading of nerve injury was found to be inconsistent among the included articles, making direct comparison of results difficult. Conclusions: Recommendations for assessment and diagnosis of trigeminal nerve injury have been made based on the best available evidence from the review. There is an urgent requirement for a consensus in diagnostic criteria, criteria for assessment, and outcome reporting among stakeholder organizations to improve knowledge in this field.