Ernest Syndrome: A Systematic Review of the Literature

Aims: To conduct a systematic review of the available evidence regarding the clinical characteristics and treatment of Ernest syndrome. Methods: A systematic search was carried out in the EBSCOhost, Embase, MEDLINE, ScienceDirect, Scopus, Web of Science, and Trip databases. The free terms "stylomandibular ligament" and "Ernest syndrome" were used, and the Boolean operator "OR" was used for connection of the terms. The research protocol was registered in PROSPERO (CRD42018112914). The results of this study are presented according to the PRISMA statement, and risk of bias was assessed according to the Quality Assessment Tool for Quantitative Studies of the Effective Public Health Practice Project. Results: A total of 57 articles were found, 5 of which met the selection criteria and were included in this review. The selected articles represent a population of 81 patients with primarily unilateral pain in the periauricular and mandibular areas. Diagnosis was established according to clinical history, recognition of pain on palpation of the mandibular angle, and remission following infiltration with local anesthesia. Concerning the treatments applied, infiltration with corticosteroids was highly successful, as was partial resection of the stylomandibular ligament and part of the styloid process. Furthermore, in refractory cases, the application of radiofrequency thermoneurolysis was described. Conclusion: The analyzed studies allow a better understanding of Ernest syndrome and the proposal of a tendinosis model for this condition. However, the evidence is scarce, and it is therefore necessary to carry out additional studies with better methodologic designs. Keywords: Ernest syndrome, inflammation, pain, stylomandibular ligament, temporomandibular disorders