Relationship between sphenomandibular muscle hyperactivity and visual symptoms

Abstract

This was an observational, descriptive study developed after an anatomical investigation of cadavers to identify the sphenomandibular muscle as an independent entity. The objective here was to perform a clinical and interpretative evaluation of the physiological relationships between the functions of the sphenomandibular muscle and various symptoms, thereby associating temporomandibular disorders with ocular pain. Ten anatomical sets (five cadavers) in the Department of Anatomy of the Medicine School of the Catholic University of Goiás were examined. This study was conducted between April, 2006 and December, 2008. Patients (181 subjects) suffering from temporomandibular disorder were treated in the Federal University of Goiás Dental School. Two groups were compared: Group I consisted of 58 patients with temporomandibular disorder, referred ocular pain, and hyperactivity of the sphenomandibular muscles; Group II was comprised of 45 patients with temporomandibular disorder, ocular pain, but no hyperactivity of the sphenomandibular muscles. After a clinical exam, treatments were conducted with semi-yearly follow-up exams for 2 years. Responses to the treatment were evaluated by questionnaires thereby quantifying existing levels of ocular pain. Pain was eliminated in 46 of the 58 patients in Group I (79.31%) and 8 of the 45 patients in Group II (17.77%). Our evaluation affirms that the sphenomandibular muscle, independent of the temporal muscle, has an intimate relationship with the orbit. The clinical exam allowed an evaluation of the sphenomandibular muscles in temporomandibular disorder episodes. The hyperactivity of the sphenomandibular muscle is thus significantly related to the presence of ocular-referred pain (p < 0.05).