On harelip and cleft palate

by William Rose

Mandibular Cleft.

This condition is one of the rarest that we have had to describe, so much so that Roux and Cruveilhier denied its existence, and Fergusson had seen but one case. Bouisson[27] in 1840 mentions some three or four earlier cases, and records one that he had seen post mortem himself. Since that date some six or eight instances have been noted, and the latest, with some excellent pictures, is described by Wölfler[28] ([Fig. 25]).

The cleft extends in different cases to a variable extent. Thus Nicati, Couronue, F. Petit, and Ammon saw clefts implicating the lower lip alone. Ribell[29] operated on a cleft extending to the chin, through which the saliva was continuously dribbling. Faucon (1868) and Lannelongue (1879) recorded clefts of the lip and mandible conjoined, and in both cystic swellings (presumably of the dermoid type) were found between the segments. Parisé’s (1862)[30] and Wölfler’s cases were also associated with cleft of the tongue, through its whole thickness in the former, and only at its tip in the latter.

Fig. 25.—Mandibular cleft, showing the divided lower lip, the segments being held together by cicatricial bands. (Wölfler.)

In Parisé’s case the child was fourteen days old. The lower lip was cleft through its whole thickness in the median line. The free edges were rounded as in harelip, and the cleft was continued below as a cicatricial band in the middle line of the neck as far as the sternal notch. The mandible was in two portions, which were separated from one another by a distance of two or three millimetres, bridged across by connective tissue. The tongue was entirely divided, the cleft extending back to the glosso-epiglottic ligament, and downwards between the genio-hyo-glossi muscles; each half was covered throughout with mucous membrane, and was bound to the corresponding side of the jaw by a mucous ligament or frænulum.

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As to the ætiology of these defects, but little is known.

Heredity is an undoubted factor in their production, and an investigation of the family history will in many cases elicit a confirmation of such an idea. Thus in two instances in my own practice I have been able to determine that the father, grandmother, and great-grandfather had all suffered from harelip to a greater or less extent. Mason in his book mentions several other illustrations of this fact. Liston operated on four members of one family for harelip. M. Demarquay[31] related a case in the Surgical Society of Paris, in which, from the grandparents downwards, eleven children had been born with harelip. In the ‘British Medical Journal’[32] a correspondent related his own family history, stating that it had occurred in some branch or other for the past hundred years.

An examination of the parents’ mouths should always be made when possible, and very commonly it will be found that one or both possess a short upper lip, and a high arched narrow palate. In others there is a slight groove in the alveolar process between the central and lateral incisors. I have also observed a small symmetrical crease on either side of the median line in the upper lip, indicating a tendency to, if not a natural intra-uterine cure of, a double harelip.

In some instances the deformity dies out of families, possibly from the fact that the defective condition in one parent is remedied by a more perfect development in the other; whilst in others the tendency distinctly increases, and a father or a mother with harelip will beget a family where three out of the four or five children will be similarly affected. By a proper selection of mates this deformity could probably be bred out, as well as bred up to.

The so-called Maternal Impression is looked on, especially by the laity, as another common cause of these deformities. Medical men will usually receive histories of such with a smile of incredulity, and rightly so; but some recorded cases, if true, are so definite that to condemn such an explanation too dogmatically seems scarcely to indicate a scientific spirit. The usual type of history given is that after the mother has seen the defect in the newly-born infant, she looks back over the preceding nine months to see if there were any apparent cause for the trouble, and seeking out particularly some shock or fright produced by seeing something resembling the defect in her infant often selects something trivial and irrelevant. The following authentic case is worthy of mention:[33]

A child was born deformed by a left unilateral harelip. The mother immediately asked to see the infant, declaring she was afraid it was marked, and on seeing it manifested no surprise at the appearance of its lip, stating that when about four months pregnant she received a fright, from the shock of which she had not yet fully recovered. Startled by a boy running almost into her arms, from whose face blood was streaming, she had seen a cut in the left side of the upper lip, extending through its substance into the nostril, laying bare the gums and teeth. She turned faint with fright, and could not banish the thought even after reaching home. The lad was subsequently examined, and the scar of a cut was found in that position.

In spite of such facts, however, one hesitates somewhat in accepting the antecedent alarm and the subsequent deformity in the relationship of cause and effect. The imaginary “maternal impression” probably in nine cases out of ten has nothing to do with the defect; whilst a real “maternal shock” which possibly led to the production of the deformity passes unnoticed. Mr. Carless tells me of a case recently seen by him of a cleft of the soft palate in a child, whose mother, without asking any leading questions, gave a history of a sharp attack of febrile disturbance keeping her in bed two or three weeks at a period when the fœtus could not have been more than two months old. This is the type of maternal shock we should possibly look for, rather than the more out-of-the-way maternal impressions commonly suggested.

The union of the parts entering into the formation of the palate, alveolus, and lip is normally completed by the eighth to the tenth week, and when once this has occurred in these parts no maternal impression (such as seeing a gashed lip) could, as far as we know, bring about a retrogressive change. Should some shock occur to the mother prior to that period, we can fully appreciate the possibility of its interfering with the typical growth of the parts then being produced; and the fact that the due adjustment and union of so many component parts is requisite for the normal development of the mouth and face explains why these defects are relatively so common. That a severe shock to an infant may produce coincidently a lamellar cataract and defective development of dentine is well recognised; that a similar type of shock acting on the mother should result in defective union of parts developing at that period in the fœtus is not strange; but that the real shock and the so-called “Maternal Impression” are one and the same is more than doubtful.

CHAPTER II.
ANATOMY AND PHYSIOLOGY OF THE NORMAL PALATE.

The hard palate—The velum and its muscles—The mucous membrane—The blood supply—The shape and size of the hard palate—Functions.

The palate is a more or less horizontal partition dividing the month from the nasal cavity, and consists of a firm bony plate in front (the hard palate) with a freely moveable membrano-muscular velum behind (the soft palate), which under varying conditions of muscular action can either open or close the communication between the nose and pharynx.

The bony palate forms the vaulted roof of the mouth, the central and posterior parts of which are nearly horizontal; and on all sides, except at the back, it is bounded by the alveolar ridge. Into its formation several bones enter; in the adult skull one usually sees posteriorly a cruciform suture indicating the limits of the superior maxillæ and palate bones; but even in the adult, evidence is forthcoming in the existence of traces of sutures to indicate that the anterior part of the palate is formed independently of the part immediately behind it. Thus Mr. Carless tells me that a cursory examination by him of a few dozen adult skulls picked up at random in the Museum of the College of Surgeons revealed the fact that in quite one half of them traces of sutures could be seen extending outwards from the posterior part of the anterior palatine canal; and a similar examination by him of 40 skulls from the Museum of King’s College of many nations and various ages showed a similar result. In almost all there was distinct evidence of the suture in the median line; in 21, the maxillo-intermaxillary suture was indicated; whilst in 10 skulls, representing the period from infancy to young adult life, both the above were seen in all, and 7 showed traces in addition of a suture placed between them on either side, and which we shall describe hereafter as the endo-mesognathic. Kölliker[34] similarly records that out of 325 adult skulls examined, 96 of them showed definite traces of the maxillo-intermaxillary suture. Albrecht[35] declares that nine tenths of the skulls in the Königsberg and Kiel Museums from children under five years of age reveal the existence of five intermaxillary sutures, proving that there are four separate portions to the so-called intermaxilla. Each portion carries an incisor tooth, and the canine is developed immediately at the junction between the outer portion and the maxilla. Occasionally there are three incisors on each side, the jaw being then called hexaprodontous; the extra tooth is developed from the inner segment of the intermaxilla (or endognathion), the outer segment (or mesognathion) carrying as usual only the lateral incisor. The accompanying illustrations well indicate this arrangement of sutures and teeth ([Figs. 26 and 27]); the importance of these facts will be emphasized later. All traces of the facial aspect of these sutures disappear quite early in life.

Figs. 26 and 27.—Diagrams to represent the normal human upper jaw of a child, with four and six incisors respectively, and also indicating the five intermaxillary sutures. (After Albrecht.)

EG, MG, XG. Endo-, meso-, and exo-gnathion. e. Inter-endognathic suture. f. Endo-mesognathic suture. g. Exo-mesognathic suture. i₁. Central incisor. i₂. Lateral incisor. iₐ. Accessory incisor. c. Canine. m₁. First temporary molar. m₂. Second temporary molar.

The bony surface of the roof of the mouth is perforated by numerous small foramina for the transmission of the nutrient vessels to the body of the bone, pitted for the lodgment of mucous glands, and grooved longitudinally for the transit of vessels. At the postero-external corners the posterior and accessory palatine canals give entrance to the posterior palatine vessels, and nerves; and anteriorly in the median line is the anterior palatine canal transmitting the naso-palatine vessels and nerves.

The soft palate is a moveable curtain, consisting of a membranous expansion or aponeurosis attached to the posterior extremity of the hard palate by firm fibrous tissue. Incorporated with it are five pairs of muscles, controlling its movements; it is covered by a smooth thin mucous membrane, and terminates posteriorly in the uvula. The arrangement of these muscles is important, not only from their normal physiological functions, but also from their irregular action and effects in cases of cleft palate ([Fig. 28]). They may be arranged in groups: two, the levator and tensor palati, form a superior group; the azygos uvulæ is intermediate; and the palato-glossus and palato-pharyngeus form an inferior set. Arising from the extremity of the petrous bone, the levator passes downwards, and spreading out below unites with its fellow in the whole length of the median raphe. The tensor arises from the navicular fossa of the internal pterygoid plate, and after being reflected around the hamular process, its action there being assisted by the interposition of a bursa, is attached to the anterior portion of the aponeurosis and to the hinder part of the bony palate. The combined action of these muscles raises and makes tense the velum, and in addition influences the Eustachian tube; but the levator is by far the more important. The azygoi uvulæ muscles arising from the median raphe and spine of the hard palate descend to the tip of that process, and are thus able to regulate its length.

Fig. 28.—Muscles of palate dissected. The cut represents the posterior nares and upper surface of the soft palate.

a. The levator palati. b. The inner bundle of fibres of the palato-pharyngeus, forming the posterior pillar of the fauces, c. The palato-glossus. d. The tensor palati; the cartilaginous extremity of the Eustachian tube is seen in front of this latter. e. The posterior extremity of the inferior turbinated bone. f. The septum. g g. The uvula on each side stretched apart. (Fergusson.)

The two descending muscles are placed in the pillars of the fauces, forming the lateral prolongations of the velum, and the tonsils lie in a recess between them. The palato-glossi arising from the tongue ascend in the anterior pillars of the fauces, and spreading out on the anterior surface of the velum unite in the median raphe. The palato-pharyngei start from the median raphe in two lamellæ enclosing the termination of the levator muscle; they descend in the posterior pillars of the fauces, and being attached to the pharyngeal wall between the superior and middle constrictors, by their contraction assist in raising the pharynx during deglutition.

The nervous supply of these muscles requires little notice here; suffice it that the superior set and the azygos are supplied by the facial nerve, the inferior set from the pharyngeal plexus.

The mucous membrane of the hard palate is of the usual oral type, and only differs from that of the rest of the mouth in its close attachment to the periosteum, from which in fact it is almost impossible to separate it. It is thick, dense, rather pale and much corrugated, especially in front and at the sides, whilst behind over the velum it is smoother and thinner. In it are many small glands (palatine glands) which extend down to the periosteum. In the median line is a well-marked raphe, extending anteriorly to a prominence indicating the position of the anterior palatine canal. The rugose condition of the membrane over the hard palate is not seen in young children; it supervenes later in life.

The vascular supply of the palate is free and abundant, a circumstance which is of the greatest surgical importance in that it permits of the free detachment of the soft structures from the hard by long lateral incisions, and the necessary manipulation of these in uranoplastic operations without any fear of loss of vitality, provided that the patient’s health and constitution are tolerably sound, and that sufficient pedicle is left in front and behind.

The mucous membrane of the hard palate derives its blood supply from two of the terminal branches of the internal maxillary artery. The naso-palatine descend through the anterior palatine canal, and entering the palate at the incisive foramen (foramina of Stenson) assist in supplying the anterior portion, anastomosing with the terminations of the more important posterior or descending palatine, which find their way to the palate from the spheno-maxillary fossæ through the posterior palatine canals. Each of the latter arteries on reaching the palate sends branches to the velum and tonsils, and its main twig runs onwards in a groove of the bone to supply the mucous membrane and glands of the hard palate and gums. Its usual position is parallel to the alveolar border, and about three quarters of an inch from it; but this varies considerably. The artery can often be felt pulsating as it emerges from the bone, and is very likely to be divided in the lateral incisions made during the operation of uranoplasty; but the knife should be carried external to it, if possible, so that the trunk of the vessel may be preserved in the flap. The bony palate derives its blood supply not only from its lower surface but also from its upper, and hence detachment of the inferior periosteal covering does not lead to death of the bone. The soft palate derives its blood from three sources, viz. the ascending palatine of the facial, the ascending pharyngeal, and the posterior palatine of the internal maxillary. The two former reach it through the sinus of Morgagni, i. e. over the upper border of the superior constrictor muscle, forming loops of anastomosis on its posterior aspect with similar branches on the opposite side; the last supplies the anterior palatal surface.

The normal shape of the palate is a regular arch, bounded laterally by the gums and alveoli into which the teeth are implanted so as to describe a parabolic curve, being normally uninterrupted at any spot by spaces or diastemata. The height and curvature of the palate vary considerably in different individuals, not only from inherited peculiarities, but also from acquired conditions dependent on the teeth. A person with a good set of sound teeth will probably own a regular well-formed palate; whilst if sundry of the upper permanent teeth are lost during the stage of adolescence, the palate is likely to become high and narrow from the falling in of the jaw. This is especially the case if the incisor teeth are lost.

The shape of the palate in a child of two years does not differ so markedly as one would at first expect from that of an adult except in length, and the reason for this is plainly the existence in the latter of three additional teeth on each side. Its increase in length is from 20 to 30 millimetres, whilst its breadth is only augmented by 10 to 15 mm., and this mainly posteriorly. When once the permanent incisors, canines, and premolars are developed, the anterior portion of the palate alters but little in shape, unless any of these teeth be lost, and the gaps not artificially maintained.

Dr. Ehrmann[36] states that the alveolar border in front of the canine teeth forms a nearly regular semicircle, with a posterior transverse diameter of 22-26 mm.; thence the alveoli diverge regularly, adding to the diameter about 2-4 mm. for each tooth. He gives the following measurements as the mean of many observations:

	From 2-6 yrs.	From 7-10 yrs.	From 11 yrs.
Interval between canines	22-25 mm.	23-27 mm.	25-28 mm.
” 1st premolars	24-29 ”	25-30 ”	27-30 ”
” 2nd ”	26-31 ”	28-32 ”	31-34 ”
” 1st molars	—	—	32-37 ”

Oakley Coles[37] has carefully investigated the size of the palate in several series of skulls in the Museum of the College of Surgeons, and gives the results as follows:

Of 34 adult skulls of European origin, the average length was 49 mm., the average width at the second bicuspid was 35 mm., and the average height from the margins of the alveoli 9 mm.

Of 32 adult skulls of mixed races, the average length was 54 mm., the width 35 mm., and the height 12 mm.

The frequent association of inherited mental and nervous weakness with a high arched palate is now a well-established clinical fact. Thus Savage states that in “Genetous Idiocy” (i. e. idiocy which starts in fœtal life, and cannot be traced to any specific disease) the palate is usually keel-shaped, the molar teeth being closely approximated; they are also late in appearing and deficient in number. “Although this kind of palate may be present in healthy individuals or in those suffering from ordinary insanity, if it be associated with weak-mindedness or moral peculiarities in youth I believe one is justified in saying that the tendency to moral or intellectual deficiency is congenital.”[38] Only recently Dr. F. Warner has reported[39] to the Psychological Section of the British Medical Association the results of an investigation as to the occurrence of deformities amongst school children, and their relationship to defective vital and mental conditions. Out of 5344 children examined, physical deformity was noted in 399 cases, and of these 274 were boys and 125 girls, i. e. in the proportion 9·8 per cent. and 5 per cent. respectively. It was found that of these 25 per cent. exhibited evidences of low nutrition, 36 per cent. evidences of nervous weakness, and 31 per cent. of mental dulness. 117 cases were noted of deformity of the palate, 77 boys and 40 girls; and of these 35 per cent. gave signs of low nutrition, 39 per cent. of nerve weakness, and 35 per cent. of mental dulness. These defects were more marked and more frequent in the pauper than in the elementary public schools, in the proportion of 4·2 to 2·2. As to the character of the malformations, the following are the numerical statistics: In 105 cases, the palate was arched, narrow, high or vaulted; in 8, it was 𝖵-shaped; in 4 it was of the flat type.

Dr. Langdon Down[40] had previously noticed and pointed out this frequent relationship, remarking that as the result of a large number of careful measurements of the mouths of the congenitally feeble-minded and of intelligent persons of the same age, he found with few exceptions a marked diminution in the transverse measurement between the posterior bicuspids, resulting in an inordinate vaulting of the palate. There was often noticed an actual deficiency in the bony structures of the posterior part of the hard palate, causing the velum to hang down abnormally, interfering with phonation.

The function of the hard palate is mainly mechanical. Acting as a partition between the nasal and buccal cavities, it prevents nasal mucus from falling into the mouth, and, by presenting an opposing surface to the tongue, allows of the production by the latter of the vacuum necessary for suction, and enables the tongue to direct the food towards the alveoli, and to disintegrate soft particles, thus assisting mastication. It is also an accessory to the development of taste by enabling particles to be evenly spread over the back of the tongue. For the production of articulate speech the hard palate is an indispensable factor, and the quality of the voice is much influenced by its contour.

The functions of the soft palate are mainly related to the acts of respiration, deglutition, phonation, and articulation.

1. In respiration.—If the mouth is closed, and the respiration purely nasal, the velum hangs loosely, and allows free passage of air through the posterior nares. If the mouth is open, the velum is raised, and air passes freely through the fauces to or from the larynx. When air passes simultaneously through nose and mouth, the velum hangs in a more or less flaccid condition midway between the two extremes, and sometimes, when absolutely relaxed, vibrates, giving rise to snoring or stertor.

2. In deglutition.—The passage of food into the nose is prevented by the closure of the posterior nares. This is effected by elevation and tension of the velum, the levator and tensor muscles acting in unison, so that its position becomes almost horizontal. The raised velum meets the posterior wall of the pharynx, which advances as the result of the action of the upper horizontal fibres of the superior constrictor, and the closure is completed on either side by the approximation towards the median line of the posterior pillars of the fauces from the action of the palato-pharyngei muscles contained therein. These, acting from the soft palate as a fixed point, and raising the pharynx to grasp the bolus of food, straighten the walls of the sphincter-like isthmus faucium, and so guide the food as down an inclined plane. The tension of the velum also assists in this guidance. That the above is the action of the palatal structures is proved by the results of their imperfect development or paralysis, e. g. in post-diphtheritic paralysis, where the naso-pharyngeal cavities remaining unclosed, food (especially if fluid) regurgitates into the nose.

3. In phonation and articulation.—The soft palate is here of considerable importance, inasmuch as it is needed to cut off the naso-pharynx and nasal cavities from the oral pharynx. When defective or paralysed, a certain amount of nasal resonance is imparted to the voice, which, however, is less noticeable during vocalisation than in articulation. For the production of clear normal voice-sounds it is essential that the separation between nose and mouth should be absolute, except for the sounds m, n, and ng. The American twang is probably due to a slight relaxation of the soft palate, permitting a small percentage of voice-sounds to pass through the nose. Dr. N. W. Kingsley[41] has recently published some excellent diagrams illustrating the position of these parts during the production of definite sounds, and for all, except those mentioned above, the velum is horizontal, and in contact with the posterior pharyngeal wall.

CHAPTER III.
DEVELOPMENT.[42]

Normal development of mouth, face, nose, and teeth—Ossification—Development of intermaxilla; old ideas (Goethe’s, &c.); Albrecht’s theory—Harelip; position of cleft in alveolus, and in lip—Dentition; accessory teeth—Development of other deformities.

Before discussing from an embryological standpoint the various deformities which we have already described, it is essential for us to consider the normal process of development of the parts entering into their formation.

About the end of the third week of intra-uterine life, the anterior cerebral vesicle becomes acutely bent over the end of the notochord, and a marked depression is seen on the ventral aspect of this, constituting what is known as the Stomodæum, or primary buccal cavity. This, however, is formed rather by the outgrowth of surrounding processes entering into the formation of the facial elements than by any definite or distinct involution of epiblast. The cavity is bounded posteriorly and superiorly by the cephalic flexure of the cerebral vesicles, and inferiorly is separated from the cephalic portion of the intestine by a septum. This becomes perforated at a slightly later date (eighth or ninth week), and communication is thus established between the stomodæum and intestine. Anteriorly, the opening is at first stellate in shape ([Fig. 29]), but soon assumes the form of a transverse cleft by the union in the middle line of the first pair of post-oral branchial arches, in which are developed the primary cartilaginous bars on either side, known as Meckel’s cartilage, the anterior part of which goes to form the inferior maxilla, and the posterior part the malleus. The soft parts around develop into the lower portion of the cheek, the lower lip and chin ([Fig. 30]).

Fig. 29.—Head of fœtus, of about 5 weeks, from ventral aspect (after His), showing the primitive stomodæum bounded above by the undivided fronto-nasal process, laterally by the maxillary, and below by the still separate mandibular processes. The quinqueradiate appearance is well represented. (Sutton.)

Fig. 30.—Head of fœtus from ventral aspect of a little later date (6-7 weeks). The mandibular processes have now united; the orbito-nasal fissure has come in contact with the ocular vesicle, and the fronto-nasal process has developed into external and internal nasal (or globular) processes around the nasal fossæ (after His). (Sutton.)

At the same time that this mandibular arch is being developed, other changes are occurring around the upper part of the stomodæum, viz. the shutting off of sacs lined with epiblast to assist in the formation of the organs of special sense, and the outgrowth between them of fleshy processes which by their later amalgamation form the facial skeleton and coverings. Three of these involutions of epiblast occur, two communicating more or less with the stomodæum, viz. the nasal and ocular; whilst the third, or auditory, is separate. Expansions from the cerebral vesicles meet them, and by further changes, unnecessary to particularize here, the organs of special sense are elaborated.

Fig. 31A.—Head of fœtus at a somewhat later date (8 weeks) as seen from the front, showing the nasal and maxillary processes in close apposition, and the clefts between them diminishing in size.

Fig. 31B.—The same, seen from below, the mandibular process having been removed.

i.m. Central portion of fronto-nasal process, m.n.pr. Internal nasal process. pr.gl. Globular process, or the lower rounded extremity of the former. l.n.pr. External nasal process. m.x. Maxillary process. m.n. Mandibular process.

The most anterior of these depressions are the primary Olfactory pits which appear on either side on the lower surface of the wall of the anterior cerebral vesicle at a very early date. They are at first merely depressions surrounded by a raised margin; but subsequently they become pyriform by the extension of the lower end as a groove into the stomodæum. Each pit and groove is bounded laterally by thickened rounded outgrowths developed from a broad median fleshy protrusion from the same part of the cerebral vesicle, the fronto-nasal process; these are termed respectively the external and internal nasal processes, the latter being also named by His the globular processes ([Fig. 30]).

These Globular processes are separated in the median line by a groove which is subsequently obliterated by their amalgamation to form the central portion of the upper lip (“Philtrum” of German authors), and from their deep aspect the inner segments of the intermaxilla (endognathia). Above this groove is a central flattened median portion of the fronto-nasal process, from which subsequently the prominence of the nose is developed ([Figs. 31A, 32, and 33]), a result of the continued growth from its deeper aspect of the ethmo-vomerine plate.

The external nasal process forms the ala nasi and the soft parts in its immediate neighbourhood, extending downwards a little distance, but probably not so far as the red margin of the lip. From its deeper aspect the outer portion of the intermaxilla (mesognathion) is developed, and in it appears the germ of the lateral incisor. It also serves to separate the nasal pit from the second epiblastic intrusion which assists in the formation of the eye. The lower boundary of the naso-orbital fissure which passes from the primary ocular involution to the stomodæum is formed by the maxillary process, which is usually described as an upward extension of the mandibular process, but which probably arises separately as a pre-oral branchial outgrowth. From this is developed the whole of the superior maxilla, except that portion which is intermaxillary, and also the greater part of the cheek.

Figs. 32 and 33.—Later stages of development of fœtal head.

About the sixth week the stomodæum shows signs of division into upper and lower segments by the outgrowth from the deep aspect of each maxillary process of horizontal palatal plates, which by their junction in the median line form the rudiments of the hard and soft palate, separating thus the nasal and buccal cavities. The anterior portion of these unite with the lateral aspects of the deeper parts of the fronto-nasal process, leaving a space of greater or less dimensions in the median line, known as the anterior palatine canal, which serves subsequently for the passage of nerves and vessels, and for the lodgment of the “organ of Jacobson” in animals in which it occurs.

The upper or nasal cavity is again subdivided into lateral halves by the growth downwards from the under surface of the fronto-nasal process of a central vertical septum, to become in time the cartilaginous septum nasi and the bony ethmo-vomerine plate, uniting at its lower border with the primary fleshy palatine processes ([Fig. 34]).

The tongue grows as a fleshy protuberance from the floor of the stomodæum; antero-lateral segments on either side from the conjoined second and third branchial arches unite with a central posterior growth from the tuberculum impar in an inverted 𝖸-shaped manner. At the point of junction of the segments is a depression from which the thyroid gland develops, indicated in later life by the foramen cæcum.

Fig. 34.—Diagrammatic representation of the development of the palatal processes and of the ethmo-vomerine plate, seen in vertical section. (After Gegenbaur.)

a. Ethmo-vomerine plate. b. Palate processes. c. Tongue. d. Buccal cavity. e. Nasal cavity.

Each of these primary epiblastic pits is at a later date almost entirely cut off from its connection with the buccal cavity. The external and internal nasal processes of the fronto-nasal outgrowth unite below the anterior olfactory pits, and thus surround the anterior nasal apertures, and separate the nares from the mouth. The external nasal and superior maxillary processes are also freely amalgamated except along one small deep track, which remains patent to form the nasal duct and lachrymal passages; and probably the internal nasal and maxillary processes unite below the external nasal process to establish the continuity of the red margin of the upper lip. The union of all these various parts has been completed by the sixth to the tenth week of normal fœtal life; the external nasal and superior maxillary processes unite first, and by the sixth week are becoming closely approximated to the central portion of the fronto-nasal process, a time when the palatal processes are only indicated as slight ridges. By the ninth week the alveolus and upper lip are complete, and union of the palate is commencing from before backwards, being usually completed even to an indication of the uvula by the tenth week.

Whilst the later stages of these developmental processes are in progress, points of ossification have been appearing in many places to form the cranial and facial skeleton. A full knowledge of this subject is still unattained, but the researches of Goodsir, His, and others have thrown much light on hitherto dark passages. There are two main sources of origin of the bones of the skull, viz. from cartilage and from membrane, and it is important to appreciate the portions of the skull which originate from each of these sources respectively. The bones laid down primarily in cartilage are mainly those forming the base of the skull and their anterior prolongations. Thus about the fourth week of intra-uterine life the basis cranii consists of a cartilaginous mass surrounding the upper end of the notochord, and prolonged anteriorly around the pituitary fossa as two cartilaginous bars, the trabeculæ cranii, into the fronto-nasal process. From the anterior extremity of this the nasal bones and cartilages are developed, and from the under surface the ethmo-vomerine plate. The transformation of the primordial mesoblastic undifferentiated tissue into recognisable cartilage is occurring from about the fourth or fifth week until the eighth, when ossification at different centres is apparent. To the development of the intermaxilla we shall refer in detail later; suffice it to say here that the ossifying centres appear about the eighth week, and by the twelfth to the fourteenth the whole process is ossified, and the space between the maxillæ closed except posteriorly, where the anterior palatine canal remains permanently patent; the component parts of the bone, however, are not united until a later date. There are two other cartilaginous foci from which ossification ensues, viz. the pterygo-palatine cartilage in the superior maxillary process, a delicate bar from which arise in part the pterygoid and palatine plates; and Meckel’s cartilage in the mandibular process for the production of the mandible and malleus. All the other facial bones are developed from membrane, more or less in connection with these bars. The vomer is ossified from a single nucleus appearing in the upper part of the ethmo-vomerine plate, about the ninth week; from this two laminæ are developed, which, passing downwards and forwards on either side of the middle line, embrace the septal cartilage. The amount of the osseous material increases from behind forwards, until at maturity a median osseous lamina remains which is grooved only anteriorly.

The palate bone develops from a single centre appearing about the eighth week at the junction of the horizontal and perpendicular portions. The superior maxilla is supposed to arise from four separate foci of ossification, viz. for the alveolar arch, for the palate, for the orbito-malar portion, and for the naso-facial segment. All these are united together by the third month.

It is unnecessary here to discuss the development of the teeth beyond stating that the thickening of the epiblast covering the gums, which occurs as the earliest sign of the production of the milk teeth, is to be seen about the forty-fifth day, when as yet there are no signs of ossification of the maxilla, and by two and a half months a distinct involution filled with cells is evident. Calcification commences about the eighteenth week of intra-uterine life, and extending from crown to fang is usually not completed until from twelve to twenty months after birth.

By the fifteenth week of embryonic life preparation is being made for the development of the first four permanent molars, and soon afterwards in the sixteenth week occur the inflections of the mucous membrane giving rise to the enamel organs for the twenty anterior permanent teeth; and from this period until the birth of the infant the germs of the twenty-four permanent teeth are passing through the various stages preparatory to calcification, so that at birth the child has not only twenty milk teeth with calcification nearly complete, but also the germs of twenty-four permanent teeth. Calcification commences in twelve of these latter during the first year of life, viz. in the first molars and the incisors, and spreads from the crown in which it starts to the fang. In the case of the incisors this process is not completed until the tenth year.[43]

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The question as to the ossification of the intermaxilla has been purposely omitted hitherto, that the subject and its morphological relationship to congenital deformities might be more fully discussed.

In the time of Galen[44] the presence of the intermaxilla as a separate bone had been demonstrated in apes and lower animals, and its existence in man inferred, although probably not actually seen. This opinion held its ground till the sixteenth century, when Vesalius attacked it, maintaining that no such bone existed in man, and its absence was even claimed as a distinguishing feature from the lower animals. The first to actually discover and notify the separate existence of the bone in the human skull was Dr. Robert Nesbitt,[45] who, in a lecture before the Royal College of Surgeons in 1736, described and figured the suture crossing the anterior part of the palate at all times of life, and maintained that during intra-uterine life each superior maxilla “is generally divided into two distinct parts, the sutural line running from between the dentes canini and incisivi up to the bottom of the nose.” But the merit of appreciating the importance of this fact belongs to Goethe[46] and Vicq d’Azyr,[47] the former of whom, in the year 1779, demonstrated the existence of the intermaxilla in the human fœtus, and, as the outcome of this discovery, promulgated in 1819 the theory that in alveolar harelip the cleft in the alveolus occurs at the maxillo-intermaxillary suture, i. e. between the lateral incisor tooth and the canine. This opinion has been believed and handed down through successive generations of surgeons until the present day, but more recent and exact research has so increased our knowledge that it cannot now be considered correct. Many painstaking embryologists have, during the last ten years, been investigating this subject; but the honour of raising the question as to the morphological position of the cleft in harelip lies with Professor Albrecht of Brussels, who in a masterly series of papers has fully established the fact, observed also by others, that the intermaxilla is not developed en masse, but is formed by the coalescence of four segments, two on either side; and he maintains that the cleft in alveolar harelip lies not between the maxilla and intermaxilla, but between the inner and outer intermaxillary segments. These have been named respectively the endo- and meso-gnathion, whilst the maxilla proper is called the exognathion. According to Albrecht, therefore, the cleft is not situated along the exo-mesognathic, but along the endo-mesognathic suture.

Much controversy has been lighted up by this pronouncement, but here only a few of the points of interest and importance will be discussed.

The development of the intermaxilla from two centres on each side may be accepted as a proven fact. It was first maintained by the late Mr. Callender,[48] who stated that these bones have a lateral wedge-shaped sutural surface, fitting into a groove in either superior maxilla, and that the alveolar processes of the latter extend forwards, forming the anterior walls of the sockets of the central incisors, and so fix the bones in position. A confirmation of the idea that the anterior alveolar walls of the incisor teeth are formed in this way was sought in the well-established fact that these particular parts are very imperfectly developed in those cases of alveolar harelip in which the os incisivum is isolated from the superior maxillæ; but such is probably due to the abnormal condition and position in which the bone is developed, rather than to the loss of the maxillary “clip.” And certainly the most recent researches tend to prove that the maxillæ have no share in the formation of the alveoli of the incisor teeth.

Sir William Turner and other anatomists have fully confirmed this method of development from four ossific centres, and important additions to our knowledge of the subject have been made recently. Thus M. Gilis[49] describes and figures the condition of the palate as seen in a six-months fœtus, where it was clearly demonstrated that the intermaxillary portion formed a sort of lozenge-shaped prism fitting in between the two maxillæ, and consisting of four portions of bone, the sutures between these being perfectly clear and distinct ([Fig. 35]). The posterior extremity of the short axis of the intermaxillary segment corresponds to the anterior palatine canal, and the anterior surface forms the median anterior alveolar border, no process of the superior maxilla closing in the alveoli in front. The upper border of the bone forms the floor of the nasal apertures.

Fig. 35.—Bony palate of a fœtus of six months, showing the development of the intermaxilla in four portions.

a. Endognathion. b. Mesognathion. c. Exognathion. d. Anterior palatine canal. e. Endo-mesognathic suture.[50] f. Exo-mesognathic suture. (After Gilis.)

Biondi, of Breslau,[51] has completed the observations necessary for the establishment of this fact by demonstrating the four actual points of ossification in many fœtal skulls of different dates, which had been specially prepared for the purpose. Moreover, as mentioned before ([p. 27]), traces of the five intermaxillary sutures, when looked for, may be found in many adult and in the majority of young skulls.

The fourfold division of the intermaxilla being granted, it is obvious that a cleft through the alveolus such as that occurring in alveolar harelip happens at one of the two following situations, either along the endo-mesognathic, or through the exo-mesognathic suture, i. e. between the component elements of the intermaxilla, as Albrecht declares, or between the maxilla and intermaxilla, as Goethe suggested—a claim which has been vigorously defended by Kölliker against its newer rival.

The relative position of the clefts is indicated in the diagrams appended ([Figs. 36, 37, and 38]).

Fig. 36.—Diagram representing the old or “Goethe” theory of alveolar harelip, indicating both central and lateral incisors as developed from one intermaxilla on either side, and the alveolar cleft between the maxilla and intermaxilla.

M. Maxilla. IM. Intermaxilla. i₁. Central incisor. i₂. Lateral incisor. c. Canine. m₁. First molar. m₂. Second molar.

Figs. 37 and 38.—Diagrams to represent the “Albrecht” theory of harelip, in conditions where the alveolus contained four or six incisors respectively.

EG. Endognathion. MG. Mesognathion. XG. Exognathion. i₁. Central incisor. iₐ. Accessory incisor. i₂. Lateral incisor. c. Canine. m₁, m₂. 1st and 2nd molars.

Albrecht’s papers on the subject are numerous, and contain a large amount of interesting material which space forbids us to introduce here; and one must refer readers, desirous of knowing more, to the appended list of his chief works.[52] But the arguments in favour of his theory may be briefly stated to be drawn from the following facts:

Fig. 39.—Drawing of an adult upper jaw with right-sided alveolar harelip and cleft palate, and the vomer attached to the left palatal margin. A rudimentary mesognathion bearing the stunted lateral incisor is shown on the outer side of the cleft.

i₁, i₂. Central and lateral incisors, x. Inter-endognathic suture. y. Exo-mesognathic suture. (After Albrecht.)

1. That in cases of alveolar harelip, a small portion of bone has been found in many instances on the outer side of the cleft, quite distinct from the maxilla. This is claimed to be the mesognathion, separated by the cleft from the endognathion, and by a distinct suture from the exognathion. A picture ([Fig. 39]) is appended of an adult skull taken from the museum of the Royal Anatomical Institute of Kiel, which clearly shows a small distinct flake of bone in the required position, extending back as far as the ordinary site of the anterior palatine canal. Such has been also found in children’s skulls, and very distinctly in a series of horses’ skulls with alveolar harelip. (For figures of such, v. ‘Langenbeck’s Archiv,’ xxxi, 2.) But this condition, indicating the distinct entity of the mesognathion, is not very commonly to be demonstrated in human pathology, inasmuch as the suture is early obliterated. But its existence is indicated by the dentition, to which we must now turn.

Fig. 40.—Drawing of a case of double alveolar and palatine cleft with projecting os incisivum, to show the lateral incisor on outer side of the cleft.

i₁, i₂, c, m₁, m₂, represent the alveoli of the teeth as in [Figs. 26 and 27]. v. Vomer. B. Palatal process of superior maxilla united to the meso- and exo-gnathion. A. Os incisivum, consisting of the two endognathia, and bearing the alveoli of the central incisors. (After Albrecht.)

2. That in alveolar harelip there is in a large number of cases a distinct precanine or incisor on the outer side of the cleft. This is well shown in [Figs. 39 and 40]. In the former, an adult skull, the mesognathion is distinctly seen bearing the alveolus of a precanine tooth, the lateral incisor; whilst the central bony portion (the endognathion) bears but the socket for one tooth, the central incisor. The latter is a picture of a child’s skull with double alveolar harelip and cleft palate; the os incisivum is seen separate and projecting forwards at the end of the nasal septum; it bears the sockets of the two central incisors. Outside the cleft the alveolus bears four teeth on either side, viz. two molars, one canine, and one precanine, which we cannot but recognise as the normal lateral incisor. So that the dental formula of the upper jaw might be represented thus:

In normal jaw—CI₂I₁I₁I₂C;

in double alveolar harelip—

CI₂=I₁I₁=I₂C,

where C represents the canine, I₁ and I₂ the central and lateral incisors, and the double lines indicate the position of the clefts. Careful examination of a considerable number of skulls has brought much confirmatory evidence to light, indicating the truth of the above proposition. Thus, to pick out a few facts from the mass of material available:—Sabourand[53] records two cases of unilateral harelip with cleft palate, one of which died at the age of thirty-three days. In each the dentition was typically that described by Albrecht, viz. four teeth on the side of the cleft (two molar, one canine, and one precanine), and six on the opposite (two median incisors, one lateral incisor, one canine, and two molars). Broca[54] has reported a case of a much deformed fœtus stillborn at seven months. In this there was cleft palate and double harelip with the os incisivum freely moveable, but not displaced. The bone was found to consist of two little masses, mobile on each other, and each containing two incisor germs; and on each side external to the cleft there was a precanine similar in shape to the incisors. The middle one of these three incisors was distinctly the least developed.

Again, Sir William Turner[55] has carefully investigated the dentition, as seen in casts obtained from various hospitals, of fifteen specimens of alveolar harelip, eight of which were single left-sided, four single right-sided, and three double clefts. To these he adds the records of forty-nine preparations examined and reported on by Kölliker;[56] we can here, therefore, discuss the dentition of sixty-four cases. They may be divided into two groups:

(α) In which no precanine intervened between the cleft and the canine—thirteen cases.

(β) In which a precanine existed between the cleft and the canine—fifty-one cases.

In not a few instances the os incisivum contained four teeth, and yet a precanine existed external to the cleft, i. e. in hexaprodontous jaws the cleft passed between the middle and outer precanines.

A similar condition is described by Albrecht[57] as occurring in an adult human skull in the museum of the University of Kiel. In this a cleft palate exists, with the fissure extending through the alveolus of the right side, i. e. a right-sided alveolar harelip with cleft palate. The mesognathion is plainly seen on the outer side of the cleft, bearing an incisor tooth. On the inner side of the cleft (i. e. on the left side) are the alveoli for five incisors before reaching the canine socket of the left side, so that here is a skull with six incisor teeth, and with a cleft between the alveoli of the right middle and outer precanines. And not a few similar preparations are indicated by Biondi[58] as occurring in the Berlin and Breslau collections. The condition of parts is represented diagrammatically in [Fig. 38]. Albrecht’s explanation is that the middle of the three precanines, i. e. the outer tooth in the os incisivum, is an accessory development; whilst that on the outer side of the cleft is the normal lateral incisor springing from the mesognathion.

With such facts one necessarily collates the accredited teaching respecting the number and character of the incisor teeth in man.

Normally one finds two incisors on each side, occupying the space between the canines, but it is a fact perfectly well recognised by dentists that occasionally an extra precanine or incisor is present ([Fig. 27]); and very rarely are there more than three incisors on either side. My colleague, Professor Underwood, tells me that once he has seen the cast of a jaw with at least five precanine teeth on one side only, but that was an absolute exception, and only to be explained as a vagary of nature. The more common existence of three incisors can scarcely be placed in the same category, especially when one considers that although not constant by any means throughout the series, yet amongst the mammalia one does find three incisors as an oft-repeated formula; and certainly the typical mammalian dental formula would indicate the occurrence of three incisors on each side. Hence it is possible that the occasional occurrence of three incisors in man is an illustration of the so-called “recurrence to type,” and that, under ordinary circumstances, one incisor has been suppressed; and the majority of anatomists fully concur in the belief that it is the middle one of the three which has disappeared. The occasional failure of the wisdom teeth to erupt, an occurrence which dentists tell us is increasing in frequency, is additional evidence as to the possibility of the disappearance of an incisor.

The accessory tooth in the os incisivum met with in some cases of alveolar harelip is maintained by Albrecht to be a reappearance of this lost middle incisor; and his explanation of such an occurrence seems very feasible, viz. that the existence of the alveolar cleft prevents the naso-palatine artery from anastomosing with the posterior palatine, and thus the vascular supply to the os incisivum is greater than it should be under normal circumstances; hence, there being a superabundance of nutrient material, nature uses such in the restoration of a structural unit ordinarily suppressed. The same fact (viz. the absence of the usual anastomosis) may explain why the mesognathion is (even when demonstrably present) always small and the lateral incisor not infrequently stunted or absent, and so answers the objection to this theory which has been raised on the ground that in cases of alveolar harelip an incisor external to the cleft is not invariably present.

Hence the dental formula in cases of alveolar harelip will vary as follows:

In tetraprodontous jaws—

CI₂=I₁I₁=I₂C,

or

C=I₁I₁=C;

in hexaprodontous jaws—

CI₂=IₐI₁I₁Iₐ=I₂C,

or

C=IₐI₁I₁Iₐ=C,

where Iₐ represents the accessory incisor, the other letters as on p. 51. The former of each of these pairs of formulæ represent the mesognathion and lateral incisor as present, the latter as absent.[59]

Notwithstanding the mass of positive evidence which is steadily accumulating in favour of Albrecht’s theory, there are still some careful observers who will not admit its truth. Some attack it on the ground that the intermaxilla does not consist of four portions (Kölliker, &c.); with such we have already dealt. Others object to it on the ground that any teeth existing external to the cleft are merely accessory teeth, or due to a bifidity of the canine. The arguments with which they support their opinion are derived from the following considerations:

(i) That in normal development accessory teeth do certainly occur, as in the case mentioned above ([p. 53]), whilst in a few instances of abnormality the same condition has been noted (e. g. a few cases recorded by Kölliker;[60] see also [Fig. 19], showing a facial cleft in which several accessory teeth are present along the inner margin). And the explanation given of such facts is that the involution of mucous membrane from which the teeth are developed is continuous along the alveolar ridge, and not localised to the definite spots from which the teeth subsequently erupt. This, however, is merely an opinion still sub judice, and not absolutely proven.

(ii) That in other defects accessory structures are sometimes produced in the neighbourhood, as if Nature, being baulked in her efforts of development at one spot, expends her energies in some less useful addition elsewhere. The accessory auricles and auricular appendages seen in macrostoma are cited as illustrations of this; and any precanine external to the cleft is maintained to be of a similar character. Whilst fully admitting the plausibility of such teaching, I cannot see that it explains such osseous development as occurs in Albrecht’s Kiel skulls, or such a regular appearance of an incisor external to the cleft as that indicated by the figures quoted above. The less frequent existence of an accessory tooth in the os incisivum seems much more readily explicable on such a ground.

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To summarize the principal points as to the development of ordinary harelip:

1. That the intermaxilla is derived from the union of four ossific portions, two on either side of the median line, and that these are to be known respectively as the endo- and meso-gnathion, whilst the superior maxilla is termed the exognathion.

2. That these ossific portions are developed from the internal and external nasal projections of the fronto-nasal process respectively, and that ordinarily the central and lateral incisors are developed one from each segment. Occasionally an accessory incisor is developed between the other two from the endognathion.

3. That the external nasal process does not enter into the formation of the upper lip, but terminates superficially in the depression immediately below the ala nasi (see [p. 57]).

4. That simple harelip, where the cleft is limited to the soft parts, is due to the non-union of the superficial portions entering into the formation of the lip.

5. That in alveolar harelip the cleft passes between the endo- and meso-gnathion.

6. That the os incisivum consists merely of the two united endognathia, and normally carries only the two central incisors. Any additional tooth is not the normal lateral incisor, but an accessory one, probably due to the reappearance of an old suppressed member.

7. That any precanine existing on the outer side of the cleft is the normal lateral incisor, springing from the mesognathion; but that the latter portion of bone is rarely seen as a separate entity in human skulls possessing such deformity, from early obliteration of the suture between it and the maxilla, and that it is often badly developed and the lateral incisor stunted or undeveloped from defective vascular supply.

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Having entered thus fully upon the question as to the situation of the cleft in alveolar harelip, we must now turn to the consideration of the morphological position of the oblique facial clefts, and their relations to the above.

It has been already pointed out that they commence at about the same spot in the lip margin as ordinary harelip, and thence run upwards and outwards clear of the ala nasi towards the centre of lower eyelid, following along the line of the naso-orbital fissure. Such a condition, coupled with the developmental facts already mentioned, viz. the existence of four segments in the intermaxilla and their relations to the internal and external nasal processes, suggests the following conclusions:

1. That the situation of the cleft in the lip margin is in all probability between the internal nasal and maxillary processes. The truth of this proposition depends on whether or not the external nasal process has any share in the formation of the lip. His, in his diagrams ([Fig. 30]), seems to indicate that it does not, whilst Biondi[61] claims that it does. The fact that these facial clefts commence at about the same spot in the lip margin as do the clefts in harelip seems distinctly to point to the conclusion that the superficial portion of the external nasal process is limited to the development of the ala nasi, and of the soft parts immediately around it. And this opinion goes far to explain the dimpling of the skin around and the consequent definition of the ala nasi.

2. That the situation of the cleft in the alveolus is between the meso- and exo-gnathion, so that the first tooth on the outer side, if developed, will be the canine.

3. That the upper extremity of the cleft should typically be located at either the inner canthus or about the middle of the lower eyelid; but this is not always the case. The association with coloboma iridis is readily explained by an imperfect closure of the choroidal cleft which normally occurs at the lower and inner segment of the globe.

Median harelip in its two forms is readily explained. The true median cleft is due to the non-union of the two globular processes developed from the median portion of the fronto-nasal outgrowth. If prolonged between the bones, it occupies the position of the median inter-intermaxillary suture, and so passes between the two endognathia.

The more serious and complete form is due to the non-development of the globular processes, and hence absence of the central portion of the lip, the endognathia, and of the ethmo-vomerine plate. The contour and size of the alæ nasi in pictures of this deformity suggest strongly that the external nasal processes are developed, but no record of the dentition of these rare cases is to be found.

Macrostoma is due to the non-union of the maxillary and mandibular processes, or possibly in some instances to the imperfect development of the former.

Mandibular clefts are due to the non-union of the separately developed lateral segments of the mandibular process—a deformity which must result from an earlier interference with the normal conditions of development than any of the others. Prof. Wölfler has pointed out that at the period when the branchial arches are being formed, the aortic bulb lies between their ventral extremities, reaching up even as high as the mandibular processes. If from any cause the retrogression of the heart and aortic bulb into the thorax is interfered with, then non-union of the visceral arches may result, and even a cleft mandible may thus be caused. This ingenious theory is stated only to apply to the more severe cases.[62]

Cleft palate is due to non-union of the palatal outgrowths of the maxillary processes. When the cleft extends beyond the anterior palatine canal it may pass along any of the intermaxillary sutures, but usually between the endo- and meso-gnathion on one or both sides. Inasmuch as the palate closes normally from before backwards, it is most common to find the deficiencies at the posterior rather than at the anterior end.

CHAPTER IV.
THE ANATOMY AND PHYSIOLOGY OF HARELIP AND CLEFT PALATE.

Harelip—Effect of labial muscles on deformity—Structure of os incisivum and labial segments.

Cleft palate—Arrangement and action of muscles—Shape of bony segments—Associated irregularity in shape of skull—Physiological effects in nutrition, articulation, &c.

The short description of these congenital conditions given in [Chapter I] must be now supplemented by a little more exact account from an anatomico-physiological point of view.

With regard to harelip, if unilateral, but little remains to be said, except to emphasize the fact that the deformity is not altogether due to loss of substance, but to a considerable extent to the unbalanced action of muscles, the equilibrium of which has been disturbed by the fissure. Thus the orbicularis oris, which should have a sphincter-like action, has its continuity interrupted, so that when contraction occurs, the effect will be to widen and evert the edges of the cleft. The muscles acting upon the corners of the mouth, moreover, will tend to exaggerate the deformity, and thus all such actions as laughing and crying will have a similar result.

The margins of the cleft are rounded, and the red mucous border of the lip passes up for a variable distance on either side, but does not extend to the apex except in very slight fissures. The upper part of the cleft in the more serious forms has its margin formed of skin, a fact which must not be overlooked in planning an operation for its cure, and which will be again alluded to in the next chapter.

The space between the segments of the lip is usually triangular in shape, and like an inverted V; it may or may not communicate with the nostril. In alveolar harelip the alveolus is cleft, as has been already described, along the endo-mesognathic suture; but the floor of the nose is not necessarily implicated.

The line of fissure in many instances passes through the maxillary attachment of the depressor alæ nasi, and the absence of the controlling influence of this muscle is an important element in the production of the broad flattened condition of nostril such a common accompaniment of this deformity, thus affording an explanation of the nasal distortion in cases where the alveolus is intact. If that structure be also implicated, then the floor of the nose will be deficient to a greater or less extent, and the tendency of the nostril to fall away increased.

On raising or making tense either segment of the cleft lip, the existence of strong reflections of the mucous membrane or frænula will become evident, in addition to the normal mesial frænum; these are sufficiently firm to limit the range but not to antagonise completely the action of the muscular contractions already alluded to. Moreover, unless freely divided by undercutting they will effectually prevent by their tension the parts being brought into a state of easy apposition, so necessary in order to gain primary union.

In bilateral or double harelip the maxillary segments on either side correspond in every particular with the outer segment in a unilateral cleft; but the central portion which is continuous with the columna nasi deserves special notice. It is usually ovoid in shape and stunted, appearing as if shrunken upwards from the absence of lateral support; its breadth and length are nearly equal, and there is a small portion of the red labial margin at the lower part. It is attached on its deep aspect to the os incisivum by firm muco-fibrous frænula, and in aggravated cases it appears to project amalgamated with the columna from the tip of the nose, forming the proboscis-like appendage already illustrated ([Fig. 8]).

Fig. 41.—Os incisivum, consisting of two lateral bony segments, each bearing an incisor. (Fergusson.)

The os incisivum has usually a larger superficial area than this “philtrum” of the upper lip, and hence protrudes beyond it in all directions. It forms a projecting tubercle, covered by smooth mucous membrane on its under side, with the central portion of the upper lip attached anteriorly. In a young child it consists of two little portions of bone, imperfectly united together, which in the fœtus are represented by two cartilaginous nodules, mobile on each other, and within each a separate ossific centre; in other words, it is formed by the two endognathia. Inside are found the rudiments of a variable number of teeth; ordinarily in a child’s os incisivum, operated on at the usual age (viz. one to three months), one finds on laying it open the rudiments of four teeth, the temporary and permanent central incisors, arranged in pairs, one above the other. Occasionally, as has been already mentioned ([p. 54]), one finds evidence of the development of another incisor on one or both sides of the projecting tubercle, and directed towards the cleft; but such is usually imperfectly developed and stunted. In fact, amongst all the ossa incisiva removed by Sir William Fergusson and now preserved in King’s College Museum, but few show any traces of the additional incisor, whilst the common arrangement is to find only the two central teeth ([Fig. 41]). In no case is there any evidence of the existence of more than two bony segments.

The anterior wall of the bone is always badly developed, and most commonly when displaced the growth of the whole projection is somewhat impeded, so that it is smaller than in the normal condition.

Its position may vary, being occasionally but little displaced anteriorly, though in consequence of its slight basis of support, viz. the antero-inferior extremity of the vomer, it is generally mobile; bands of muco-fibrous tissue are occasionally seen passing from it to the maxilla under such circumstances. Every variety of anterior displacement is met with, until the severest forms alluded to above are reached. If operative interference be delayed until late in life, the vomer becomes dense and hypertrophied, and the junction with the os incisivum much firmer, increasing the subsequent difficulties and dangers of treatment. More exact details as to the dentition in cases of alveolar harelip have been already given and discussed in a former chapter ([p. 51]). It is interesting to note here, however, that the temporary incisors, both in the intermaxilla and lower jaw, have a tendency to appear earlier than usual; I have many times seen incisors in such cases erupted at birth.

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Amongst the many contributions to surgery which we owe to the late Sir William Fergusson, not the least is that interesting account given of the anatomy of cleft palate, derived from a minute dissection of a case which came under his observation in the dissecting room. The specimen was obtained from the mouth of an aged female.[63] The fissure in this case was one of medium severity, implicating the velum and the posterior portion of the hard palate. The upper horizontal fibres of the superior constrictor were more fully developed than under ordinary circumstances, and would appear to have assisted in shutting off the posterior nares during deglutition and speech. The tensor and levator palati muscles were normally situated and developed, and it appeared from this dissection that the latter muscle was the main factor in drawing the velum upwards and outwards. Consequently the division of this muscle in some way or other is absolutely essential where any plastic operation is undertaken for the closure of the cleft. The palato-glossi and palato-pharyngei evidently possess the power of drawing the posterior part of the velum outwards and downwards, but they are by no means so powerful as the levator.

During muscular repose the edges of the cleft are considerably approximated to one another; indeed, the posterior halves of the velum may even touch, and the same condition to a limited degree obtains during deglutition. Fergusson rightly ascribed the latter effect to the contraction of the upper portion of the superior constrictor, which we have already mentioned is hypertrophied, the levator and tensor muscles being at the same time presumably relaxed. If the edges of the cleft be irritated, the lateral segment is instantly drawn upwards and outwards, and disappears as it were, an observation which emphasizes the necessity for the complete division of the levatores at some period of the operation.

Where the cleft extends into the bony palate, it is not uncommon to find the pitch of the palatal segments vary considerably. If the cleft be incomplete, the sides will be regularly sloped, although the vault may be higher than usual; whilst in cases of complete cleft, it is not uncommon to see an excessive upward slope of the bones like a Gothic arch, but not always symmetrical. Pollock states that “the more complete the cleft, the nearer the perpendicular are the sides of the palate;” and consequently when the soft tissues are detached from the bone in uranoplasty the flaps will fall into position more readily, and in many cases meet without difficulty in the median line. The following diagrams ([Figs. 42 and 43]) indicate how much more advantageous such a condition is than when the palatal segments approach more nearly the horizontal.

Figs. 42 and 43.—Diagrams representing the greater facility for bringing the muco-periosteal flaps together when the palatal segments are vertical rather than horizontal. (Mason.)

A B. Bony palatal segments.

A C. Muco-periosteal flaps.

My friend Mr. Oakley Coles has in his book on ‘Deformities of the Mouth’[64] gone very fully into the question of the association of abnormalities in the shape of the cranium with deformities of the palate, endeavouring to prove that the palatal defect is concurrent with, if not dependent upon, a non-development of the left lower parietal region of the cranium, i. e. of the portion of the skull overlying Broca’s convolution, which governs the function of articulate speech. Into this question space forbids me to enter here, and I would refer my readers to his excellent book, merely quoting some of the conclusions at which he arrives:

“1. There seems a definite relation between palate and cranium; certainly as to length and breadth, probably as to outlines.

“2. In palatal deformity or interference with the mechanism of speech, there seems to be in a large number of cases asymmetry of the brain-case.

“3. In strongly marked cases of malformation of the upper or lower jaws, there is equally well-marked asymmetry of the skull.

“4. In a notable number of cases this flattening of the cranium is on the left side.

“5. It is generally admitted that the language, speech, and sound centres are chiefly on the left side of the brain.

“6. Evidence is obtainable that structural defects, mechanical injuries, or pathological changes involving these parts produce defects of language and speech.

“7. In so far as functional activity and capacity may be taken as measures of organic perfection or otherwise, it may be assumed that certain cases of cleft palate, or the subjects of some other deformities in the maxillary region, who have also a deficiency in the articulate sound function are also deficient in the articulate sound nerve-centre.

“8. And as it has been shown that congenital structural defect of the brain is frequently associated with physical deformity of the skull, so it may be useful to regard the conformation of the skull as part of the evidence by which we may estimate the development of the brain.

“9. If it be possible to avail ourselves of the facts that are stated, and the inferences that are indicated, we may be able to prognose with a greater degree of certainty the future language and speech capacity of sufferers from palatal and maxillary deformities of congenital origin.”[65]

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We must now turn to the functional results of these deformities, and trace out some of the effects which they produce on the economy.

Fig. 44.—Soft metal cover to teat of feeding bottle, which can be moulded to the infant’s mouth, and act as an obturator during suction. (Mason.)

We necessarily place in the front rank the serious difficulties met with in the administration of nutrition. Where the lip alone is involved, and that only to a slight degree, but little difficulty arises, as the child is usually able to suck; but in the severer cases of cleft lip, involving also the alveolus and palate, the child’s life may be endangered from the inability to take or to swallow sufficient food. For as the cleft alveolus and lip seriously impair the power of suction, so the cleft palate allows the fluid which has found its way into the mouth to regurgitate through the nose. In many such cases spoon-feeding is the only chance for the child. To carry this out successfully the head must be thrown well back, so that the fluid may pass directly into the pharynx; in fact, the child is often obliged to drink like a bird, in which, as is well known, the communication between the mouth and nose through the non-union in the median line of the palate bones necessitates a similar manœuvre. But even when this precaution is taken, there is no doubt that many infants with fissured palate die of sheer starvation. Mr. Mason suggested the use of an apparatus such as that figured below ([Fig. 44]). It consists of an ordinary india-rubber teat attached to a feeding bottle. Over the teat is a very thin plate of soft metal, which can be readily moulded to fit the infant’s mouth, and so act as a temporary obturator. It may be used with advantage in some cases, but I have not employed it largely, preferring to trust to careful spoon-feeding. A similar contrivance in india-rubber which can be fitted to a Maw’s feeding bottle has been successfully used. A covered spoon with apertures left at either end is, in the hands of an intelligent nurse, an efficient contrivance.

Coles has devised an artificial palate attached to a shield to go over the mother’s breast ([Fig. 45]) in order to enable the infant to take its natural nourishment. It is made of thin elastic rubber, is not uncomfortable, can be kept perfectly clean, and from the shape in which it is made can be used for either breast. In exceedingly delicate children the employment of this device may be advisable.

Fig. 45.—Nipple shield suggested by O. Coles for use in cases of cleft palate. A is the apparatus fitted to the breast, and prolonged anteriorly so as to form a shield, which projects over the nipple. When in the child’s mouth it acts as an obturator, partly shutting off the nasal cavity. (Coles.)

In the severer cases it must not be forgotten that it is quite possible that some other factor is engaged in the production of the rapid wasting which in spite of every precaution may ensue, such as mesenteric tuberculosis, or some congenital intestinal or vascular defect. Whether such exist or not, the child quickly emaciates, the face becomes pinched and old-looking; the skin has an earthy appearance and hangs in wrinkles, lax and inelastic; and death, practically from starvation, soon ends the chapter.

When our patient survives the dangers of infancy and arrives at boyhood or girlhood, the regurgitation of food through the nostrils ceases, except under occasional circumstances or in very severe cases; and although the difficulties of infant nutrition are often manifested in a much retarded growth, yet there is no reason why the physical constitution of the patient should ultimately suffer. Again, the knowledge of such visible and audible defects before operative treatment has been undertaken has a decidedly depressing influence upon the mind. The subjects of this deformity, from evident consciousness of their repulsive aspect, shun the observance of others as they grow older; and so strong is the sentiment which prevails as to maternal impressions that they are studiously avoided by women in the earlier stages of pregnancy. I have often noticed a distressed or hunted expression on the face of those who had attained to adult life before surgical treatment had been undertaken; and its disappearance after a successful operation has been equally marked.

Defective articulation is another serious accompaniment of these deformities. Although this may be present to a slight degree as a result of a simple cleft in the lip, yet it is only when the palate is imperfect that the trouble is obviously manifest. The defect consists in the inability to articulate distinctly any but the open vowel sounds, and those few consonants which do not require the nasal cavity to be entirely shut off from the buccal. For the production of the labials, dentals, and gutturals, it is essential that there be a complete closure of the posterior nares; and as the mechanism for effecting this is imperfect, the production of the sounds must be similarly defective. In spite of these difficulties, it is extraordinary how adults suffering in this way can by practice make themselves understood. This inability to completely shut off the nose from the mouth is undoubtedly the primary cause of the nasal twang imparted to the voice. Even a small aperture is sufficient to give rise to a marked defect in speech; whilst cases are recorded where without any actual cleft the velum from deficient antero-posterior length could not be approximated to the posterior pharyngeal wall, and a similar condition of speech has resulted. Indeed, in many instances where a scanty palate has been successfully sutured, the cacophonic sounds may for a time persist, though to a less degree than before the operation, a result either of inability to make this contact through an uncorrected faulty habit or tension of the velum, or due to the presence of some small opening. The peculiarity of the twang imparted to the voice varies according to the amount of communication between the mouth and nose, the size of the nasal cavities, and the shape of the nostril aperture. Where the tonsils are enlarged, and adenoid vegetations exist in considerable numbers on the pharyngeal wall, the size of the communication may be reduced, and articulation thus rendered more distinct. It is a question, therefore, whether these growths should be removed unless for some pressing reason.

Singing is interfered with, though to a much less degree than is ordinary speech, although the words sung will be indistinct. Whispering, moreover, is impossible; but most of these conditions will not be very manifest if the velum alone be fissured. Mason notes that it is very difficult, and in some cases impossible, for the patients to blow out a candle; and similarly they cannot perform on wind instruments.

The passage of air into the mouth and over the tongue tends to produce dryness of the latter organ, and consequently excessive thirst. The abnormal exposure of the parts to the unwarmed air produces a tendency to nasal catarrh which is very decided; and, in fact, it is very common to find a condition of chronic granular pharyngitis present, associated with adenoid vegetations and chronic enlargement of the tonsils. Patches or crusts of dried mucus may be observed clinging to the mucous membrane, and these have occasionally been mistaken for sloughs. From these arises a peculiar odour, which, however, cannot be quite accurately described as fœtor. The falling of mucus into the mouth is another unpleasant result, and the loss of the faculty of smell is in some cases most distinct.

The sense of taste is very defective in all severe cases, from the fact that the tongue cannot be applied to the palatal surface in such a way as to bring the food successively in contact with the organs of taste; moreover, as is well known, the senses of smell and taste are closely correlated, and where smell is absent, taste is deficient. This was very well illustrated in one of my cases, where the operation for closure of a complete cleft was not undertaken until the girl was twenty-five years of age; it was entirely successful, and she told me subsequently that the ability to appreciate the tastes of different foods in a way of which she had no idea previously was not one of the least of the advantages derived from the operation.

CHAPTER V.
OPERATIVE TREATMENT OF HARELIP.

Period of operation—Statistics—Precautions to be adopted.

Operation for single harelip: incisions; sutures; dressing; after-treatment—Various plans adopted.

Operation for double harelip: treatment of os incisivum—extirpation or reposition; treatment of soft parts.

In discussing the period in the infant’s life when a harelip should be operated on, it may be laid down as a general rule that the sooner an operation is performed for the repair of the abnormal condition per se the better; but other coexistent conditions have to be taken into consideration, such as the amount of vitality, the degree of deformity, and its association or not with cleft palate; and these may lead us to postpone the operation.

A low state of vitality may be due either to a general inherited weakness, or possibly to some associated deformity in another part of the body interfering with nutrition; or, again, simply to difficulties attending the administration of nourishment owing to the cleft lip and palate; for, as has been already pointed out, suction, and therefore breast-feeding, are impossible ([p. 67]). The problem that the surgeon has to solve lies in deciding to which of these causes the asthenic condition is mainly due, and whether the infant has sufficient strength to withstand the shock of the operation, and is in a state favorable for the occurrence of primary union. If due to some inherited weakness, or associated deformity elsewhere, immediate operation would be rash in the extreme, for the child is very likely to succumb. In any such case, careful hand-feeding is alone practicable; if a steady improvement is manifested, the operation may be undertaken later. But if, on the other hand, the asthenia is evidently due to the inability to take nourishment, the child gradually getting thinner and looking half starved (as I have seen in many cases), then the first opportunity should be taken of closing the lip, as such treatment holds out the only prospect of saving the child’s life. The greater the deformity, the more difficult will the question be to decide, for with the higher degrees of malformation the operation necessarily increases in severity. If associated with cleft palate this should be performed as early as possible, as the closure of the lip enables nourishment to be taken when administered in the way indicated above ([p. 67]).

It would be well here to call attention to the fact that the early closure of the lip by the insensible and yet constant pressure brought to bear on the separated maxillæ has a most beneficial effect in narrowing the alveolar cleft. In my own experience I can testify to the decided diminution which has occurred in the width of many clefts when the lip had been closed by me some years previously, the patients having subsequently returned for operative treatment on the palate. Passavant[66] relates a case of a child whose harelip was closed at the age of nine weeks, and a year later the palate was found to be approximated without further operation, so that it merely presented a fissure. Some surgeons have attempted to gain a similar result by prolonged compression of the maxillæ. Trendelenburg,[67] on the other hand, casts doubt on this explanation of the narrowing of the palatal cleft, the existence of which he fully admits, stating he has seen the same occur in children who have not been operated on, and suggesting that it is due to the inward growth of the bones.

Three different periods have been suggested for the operation, viz.:

(a) The immediate operation—within two or three weeks of birth.

(b) The early operation—from three weeks to six months.

(c) The deferred operation—from six months to two years.

Statistics do not favour the immediate operation, for although some surgeons have obtained good results, the mortality with others has been considerable. Thus König,[68] on the one hand, records seventy cases operated on in the first month with but one death; whilst Hermann[69] gives 52·4 per cent. as the mortality of the operation during the first three months of life, and Gotthelf[70] 50 per cent. for a similar period. The latter cannot but be considered as an extraordinarily high death-rate, and possibly antiseptic precautions were not carefully observed. Trendelenburg[71] reports 44 cases treated in the course of three years with seven deaths; the infants were between three and six months old. Fifteen were simple cases, with one death; twenty-one were complicated, with two deaths; and eight most complex forms, with four deaths. Only one died within a fortnight of the operation; the remainder from intercurrent maladies. Still, however, he reckons the death-rate during the first year of life of children operated on as 41·6 per cent., explaining it by malnutrition and the want of intelligent artificial feeding. Fritzsche reckons the mortality during the first two weeks after operation as about 5 per cent., but even this is higher than I should consider consistent with the results of British surgery.

My own personal experience has been much more satisfactory, and the above figures are much too high to represent my results. Out of between 300 and 400 cases treated between the fourth and eighth weeks, i. e. by the early operation, I have had no death as an immediate result, but several have died subsequently from intercurrent maladies or defective nutrition. I attribute this success largely to the fact that I never operate upon out-patients, but always take the precaution of carefully preparing and watching them for a few days prior to operating. In the practice of the late Sir W. Fergusson the one or two fatal cases which I recollect occurred in children who were taken home immediately after the operation.

It has been claimed for the deferred operation that convulsions are liable to ensue when an infant under six months is operated on, and also that the interdiction of nursing impairs nutrition; but this has not been my experience.

From a consideration of the foregoing facts, it would appear that from the fourth week to the third month is the most favorable period for interference, and that at which the greatest proportion of success has been obtained.

In conclusion, whilst fully admitting that it is impossible to lay down rules which will meet every case, and that each must be dealt with on its own merits, I would venture to suggest the following propositions which may be helpful as a guide to practice:

1. That, cæteris paribus, it is important to close the cleft in the lip as early as possible.

2. That, under ordinary circumstances, the immediate operation is dangerous to life, and should only be undertaken in desperate cases as a means of saving it,[72] i. e. in double cleft of the lip and palate, where suction is impossible and swallowing difficult.

3. That experience shows that the sixth week may be taken as an average at which operations can be safely performed; but that if the child be very weakly, it is better to defer such treatment for a few days, until careful spoon-feeding has improved our little patient’s condition.

4. That association with cleft palate in no way invalidates the previous propositions.

In many cases of slight cleft without alveolar complication the child is able to take the breast, and as it is desirable to maintain this after the lip has healed, care must be taken that the lacteal secretion is not checked. The child is often able to suck five to seven days after operation; during that period the mother’s milk must be drawn off by a breast-pump when necessary, and should be given to the child by spoon. Any mammary inflammation is thus avoided, and the child’s diet is not changed. In many cases of severe deformity, where the child is unable to suck from the first, an early disappearance of the milk has of necessity entailed spoon-feeding. When such an infant is taken from home into hospital it is well to wait for a few days before operating until acclimatised to the change of surroundings and of diet. The general state of health should be as satisfactory as possible, and every effort must be made to ensure this; it is often politic to defer operation on this account for a short period. Any aphthous condition of the mouth should be treated by swabbing with a weak boracic solution (1-40) or by the application of mel boracis.

Anæsthesia is now-a-days invariably employed, chloroform being the agent used. Care must be taken by the anæsthetist to prevent any drop coming in contact with the wound, such an occurrence being liable to interfere with primary union.

With regard to the position of the patient, some difference of opinion appears to exist. The practice adopted years ago and described by the late Sir W. Fergusson in his manual[73] consisted in the surgeon and nurse sitting opposite one another, the latter holding the child with its head on the surgeon’s knee. To quote his own words: “A cloth should be wrapped round the chest so as to confine the arms; a pillow-case answers the purpose well, as the legs can then be secured by slipping the patient into it. Then the child should be held by an assistant with its head resting face uppermost between the surgeon’s knees; if he puts on an apron of waterproof cloth, it will answer the double purpose of keeping his trousers free of blood, and preventing the child’s head falling too low; a little pressure with the thighs will enable him to keep the head more steady.”

The majority of surgeons at the present time employ the recumbent posture on a table, a plan which I always follow, the surgeon standing behind the child’s head, and the anæsthetist and assistant one on either side. Some prefer to stand at the side of the infant, with the assistant behind its head.