Structure of the musculus uvulae: functional and surgical implications of an anatomic study.

OBJECTIVE: The role of the musculus uvulae in velopharyngeal function, its morphologic status in cleft palate, and its fate in palatoplasty procedures are subjects of controversy. The aims of this investigation were to re-examine this velar muscle to clarify its anatomic characteristics, to analyze its role in speech physiology, and to study the surgical implications of this information for cleft palate repair.

METHODS: Its attachments, morphology, and relations were examined in 18 fresh human adult cadavers by detailed dissection under 3.2x magnification and light microscopy.

RESULTS: The musculus uvulae was observed to be a paired midline muscle extending between the tensor aponeurosis anteriorly and the base of the uvula posteriorly along the nasal aspect of the velum. It had no attachments to the hard palate.

CONCLUSIONS: These findings suggest that its action is to increase midline bulk on the nasal aspect of the velum, thus contributing to the levator eminence. It may also have an extensor effect on the nasal aspect of the velum, displacing it toward the posterior pharyngeal wall. Both of these actions would serve to maximize midline velopharyngeal contact. One clinical application of this anatomic information is that the muscle should be preserved in the dissection performed during intravelar veloplasty. Furthermore, it should be recognized that the musculus uvulae is invariably divided and reoriented incorrectly in the Furlow double opposing Z-plasty.