Velar Motility, Velopharyngeal Closure, and Speech Proficiency in Cartilage Pharyngoplasty: An Eight Year Study

Abstract

It is generally accepted that velopharyngeal closure is critically important for the development and maintenance of acceptable speech patterns. In the normal manifestation of this neuromuscular complex, the soft palate tenses, lifts, and retracts in effecting a meshed contact between its superior surface and the posterior pharyngeal wall. Mesial movement of the lateral pharyn-geal walls is also probably an important characteristic of this total action. For persons with cleft palate and for others with problems of Velopharyn— geal incompetence, the primary difficulty in achieving normal velopharyn— geal closure generally results more from a failure of the velar component rather than from the pharyngeal component of the mechanism. For example, in an assessment of velopharyngeal function of 80 normal subjects and 50 cleft palate patients, Hagerty and Hill (3) found that, although there was more forward movement of the posterior pharyngeal wall in the cleft palate group than in the normal group, the magnitude of this movement and its contribution to speech proficiency could be considered to be relatively insignificant. Moreover, in a comparison of the relative extent of velo-pharyngeal closure on /a/ and /s/, these same authors found syste~ matic differences in favor of a normal group of subjects over the postoper— ative cleft palate subjects with whom they were compared. Since these differential measures could not be attributable to movements in the poste— rior pharyngeal wall, there is reason to infer that the postoperative soft palate, by reason of inadequate length or limited mobility, is the principal contributor to the relative failure of velopharyngeal closure. From these findings, it seems logical to investigate methods by which the posterior wall might be extended anteriorly to enhance velopharyngeal closure in patients with cleft palate or with other manifestations or velo-pharyngeal incompetency. In a review of such