On cleft palate : with cases in illustration of its successful treatment / by George Frederick Lane.
- Lane, George F. (George Frederick), 1828?-1856.
- Date:
- [1851]
Licence: Public Domain Mark
Credit: On cleft palate : with cases in illustration of its successful treatment / by George Frederick Lane. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![I'Oi’tion uncalculateJ to do so, from its iitimate coiinoction with the densorpart II front liaving a bony attacliment. Itoreover, this muscle is confined to the nnterior lialf of the velum, where the 'Ssure of the palate is narrowest. What, nen, is the cause of the separation of we posterior part? The answer to this nay easily he found in tlie obvious i3tion of the levator palati muscle and illlai's of the fauces. There is some lifficulty in closing the fissure in front u most cases, attributable to the greater Boensity of the parts there, and their Bi'eculiai- position in relation to the bony Bicructures, and, possibly, slightly to the loction of the circumflexus palati. I The ])iincipal action ot the cii’cnm- loexus palati is to give firmness to the eelum, esjiecially near the base, during hie action of its other muscles; but, i.x)ubtless, all the palatal muscles are oDncemed, more or less, in the produc- con of each of the varied movements of lire soft palate. The movements of the pharynx ap <'ear to have been but little understood lill a very recent period; accordingly, iio find, in Mr. Lawrence’s work upon liie Pharynx, published in 1834, tlie fob owing passage relating to the closure of lie upper part of the pharynx from com- nunication with the nose, as in swab owing. “ At the time that tlie elevation and I'sti'action of the tongne urges the iiorsel of aliment into the pharynx, lihe velum palati is drawn up against Lae choanaj narium.”* Tlie closure of the pharynx supe- liorly, occun-ing during deglutition, is irroduced by slight elevation of the soft laalate, so as to bring the upper and posterior surface of its free margin i^ainst the back of the pharynx; and my person may do this at will by ex- iiiring air through the nose audibly, and III perfectly isolated jets, while the I'louth is closed; the period imme- i.iately preceding each gush of air I larks the contact of the soft palate rrith the phaiynx. This movement of the velum is pro- bably effected by the combined action If the levator-palati and jmlato-pharyn- eeus of each side, assisted by the ^gos uvulm. The lateral cmwcd fibres II the superior constrictor approach it • * Anatomico-Chirurirical Views on the Nose, Houth, Larynx, and Fauces. on cither side, and its firmness is at- taiued liy traction of oacli tensor palati muscle. 'J’he closure of the fauces at the same jieriod is effected partly by the action of the pillars of the fauces, which con- strict it, but more especially by the elevation of the base of the tongue, which is kept in contact with the roof of the mouth by means of its ]u-o]ier muscles, assisted by the mylo-hyoidei. The soft palate and upper jiart of the jiharynx are so near each other in tlio natural state, that they are brought into close apposition by a very limited movement of the velum and sides of the latter; the kind of closure resem- bling a valve opening downwards. The proximity of tlie pharynx to the posterior nai’es may be seen from the position of its ajioneurotic attachment to the base of the skull, wliich corre- sponds to a part but little behind the free mai'gin of the hard palate; and hence the posterior wall of the jiharyns is easily within the range of the move- ments of the velum. This point has been adverted to more particularly, since the closure of the upper part of the pharynx from com- munication with the nose is described by some anatomists of the present day as efifected by an elevation of the soft ])alate, the superior constrictor coming forward at the same time to meet it. A little reflection on the relation of the parts will show that the constrictor does not come fonvard, but that (hav- ing a fixed position behind) the nar- rowing of the cavity which it encircles is obtained by approximation of its lateral walls, much in the same way; the position only being changed, that the lateral fibres of the dia])hragm descend without movement of its tendi- nous centre. The following reasons may be as- signed for this opinion:—The natural relations of the parts are such as to be efficient without such movement. The nature of the attachment of the up]ier part of the phaiynx in the middle line to the parts against which it rests, and the improbability of the space which would thus be left behind, between it and the cervical spine, being filled by other structures. In deglutition, the pressure of the tongue against the roof of the mouth, effected by its proper muscles and the mylo-hyoidei, is resisted by the tensores](https://iiif.wellcomecollection.org/image/b22424751_0005.jp2/full/800%2C/0/default.jpg)
