On pteric sutures and pteric bones in the human skull - DWC - KNAW

Huygens Institute - Royal Netherlands Academy of Arts and Sciences (KNAW)
Citation:
Broek, A.J.P. van den, On pteric sutures and pteric bones in the human skull, in:
KNAW, Proceedings, 16 II, 1913-1914, Amsterdam, 1914, pp. 634-639
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described &everaI year& ago 1) nw,)' bc used for this pUl'pose. In th is
way it will not only be posslble 10 determine the heat of Il'ansformation
of the modifications, but also to study thc eql1lllbl'ium-betweeJ1
the different fOl'ms. Several llltereSting pl'oblems may find theÎl' solution
in this way. I have cal'l'ied out ~ome prellminal'y expel'iments in
thls direction (witl! cadmium) ill colla,boratlOJ1 with Mr. W. D.
HELDERJlIAN.
8. The same may be said if we considel' the l1nmel'OUS alloys
whieh luwe an ind ustl'ial as weIl a& a scielltific lI1tel'est.
The melting point Clll'ves ba\'e to be revised, taking into_ acroullt
the allotropy of the C'omponents. Quite recentl.r the important pal't
pIayed by the previous thel'mal histol'J of aUoys Las been eliseo\'cl'cc!,
DIPPIU. 2) has pl'oved that the specifie heat of cel'lain alloys 1& different
accoreling as they are cbilled Ol' cooled slow Iy.
In explaining Ihis fact, DIPPI~L has not been able to take into
account the allotl'opy of the components of Ihe alloys he m .. pel'irnenteel
with, as OUI' papers on tbis subject c01l1d 1I0t at that time
be known to him.
9. I hope to report shol'tly on the problems which have been
inelicateel here. We will then cliscuss also sevent! phenomena whielt
al'e observeel in inelustl'Y, the corl'osion of metals in contact with
water, rustillg of iron, the decay of alnminilllu objects etc.
Utl'echt, December 1913.
VAN 'T HOFF-Lt1borato7'!J.
Anatomy. - "On lJtel'ic 8utw'e8 ({nel pteric bones in tlw IW1/lnn
skull". By Prof. A. J. P. v. D. BIWEK. (Communicn,ted by
Prof, L. BOI,K).
It is well known that the pterlc l'egion of the skull shows diffel'ent
relatiol1s 111 farm and extemion of the adjacent ELllUreS as weil al:.
in the existence of separate bon es, the so cal1ed plel'ic bones, Obsa
epipteriea.
In most of the lllunan sk.ulls the parietal anel the ala magna of
the sphenoid touch in a more Ol' less extensivc spbcl1o-pal'ietal sutUl'e,
In sorne skulls the frontal is l'eached by the temporal 'bone, then
a fronto-tempol'aL suture is formed. In this case we speak of a
processns frontalis ossis iempol'alis.
The cOllfiglllation of the pteric l'egion can be inflllenced by the
nurnber, fOl'm, extension and situation of tüe ptel'ic bones.
1) Zcitschr. f. physik. Chem. 30, 623 (1899).
2) Ann. d. Pltysik 42, 889 (1913).
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635
Au examination of tlle Sklllls of papuans, brollght home by tlle
LORl!.N'l'Z' expedition from Dlltch 8011tl1 New-Gllinea, augmented with
a number of papuan skll11s, sent fo me by the military-surgeon
DE KOOK from the same dist!'iet, sl10wed snch l'elations in the pteric
reg ion , that made a closer examination necessary.
A study of the concel'ning literatlll'e teaches, that the different
investigations on the pl'oe. fl'ontalis as weil as on the pteric bones
al'e ne~rIy all of a statistieal nature, and do ]10t reek on with the
condition of the two opposite siges of the same sknll. As a consequenee
of this way of investigation, the different forms of p)'ocesslls
fi'ontalis are alv.'ays explained in the same way. Only GRUBER 1)
mentions two forms of a fronto-temporaI SlltUl'C.
'l'he examination of 114 papllan slmlI'3 drew my attention to three
qllestions, viz. 1 that se, eral forms of proc. fl'ontalis must be discEll'lled.
2 that 1'01' the judging of the character of a pl'oeessus fl'ontalis
the two opposite sides of the same skull must ue mutually
eOf1lpal'ed and 3 that the pl'oeessus fi'ontalis and the ptel'ic bOlles
must be eompal'ed with each othe1'.
Regarding the first point I obs0rve that tvvo forms of proc. frontalis
ossis temporalis must be distingllished. I eaU these two forms of
proc~ frontalis type I and type Il.
Type I shows a projecting part at the upper border of fhe squama
temporalis, as is seen in figul'e :I. By pl'olongil1g the Sllture between
temporale and the alisphenoid in upward dil'eetion, as is done in
Fig. 1. Fig. 2.
1) GRUBER W.Über die Vel'bindung der SchJäfellbeillschuppe mit dem Stirnbeine. 1874.
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636
figlll'e 1 by a clotted line, it lOt\el!cs tbe parietal (vide figure f).
This is GIWBER'S "mittelbal'e Verbindllng". Type H shows aregutal'
enlargement of the whole squamosal in the direction of the-fl'ontal,
so, that a fronto-temporal sllture is for121ed. This is GIWBEU'S "1l111nittelbare
Vel'bindllng". J .illnction of the serond type ('an be combinecl
with a fronta1 process of the th'st type.
The number of examined skulls is 114; Ü\ 47 1 fOlll\d a frol\t9-
temporal suture i. e. in 41,14 %'
The skllih. of tbe lwo dIifel'Ant klJlds are divided as follows.
In 34 cases we have a frolltal pl'ocess of the th'st tJ pe._ In 13
cases the two sides of the &kllil are s,vmmetl'ical. In 21 the fi'onLal
pl'ocess is onl)' pL'osent at olle side. 5 of the 13 simlis with eymme·
tl'ical fl'ontal pl'ocess show a combination of tlw fil'st and the second
type, so that fl'om tbe fiJ'st' type 8 are fOllnd with the fl'ontal process
on both sides, to 21 witll the front. proc. on one side; which Lllcans
that the unilateral pl'esence is mllch 11101'e fl'equen t than the bilatel'al.
In 13 skulls the serond type ,,.,as fOllnd. Of 110 less than 12 skull&
the two sides were symmetria.l anel ün1y ollce I fOllIlcl a llnilatel'al
enlargement of tlJe s'luamosal, which proves that 1 he bilateml pl'esence
is ffillCli more frequent thall the llnilatel'al.
In the unilatel'al pl'esence of a frontal process of the fiL'st. type
I fOllnd ihis process 13 times on the left sicle of the skull against
6 times on lhe l'ight one j so the left half of tile skull sl1l'passes
stl'ongly the l'ight one in tbis respect.
An investigntion of the ptel'ic l'egion of tbe side of the skull
opposite to a frontal pt'ocess of the fil'&t type led to the following
facIs:
1. Pl'ocessus frontaJis at the 1eft side.
A spheno-pal'ietal sutUl'e at tbe l'ight sicle in 6 skulls.
An os epiptel'icum typicum "
" " " 3 "
Several ossa epiptel'ica ,.
" " " " 1 skull.
A tempol'al pl'Oc. at tbe fl'ontal
" " " " 1 "
Il, Pl'OCe&SllS fl'ontalis + os epiptericum at the left side.
An os epiptel'icum-typicum at the l'i~ht side in 2 sknlls.
IJ Pl'ocessus fl'ontalis at tbe l'iglIt side.
A spheno-pal'ietal sllture at the left side in 2 skulls.
Au os epiptericulU typicum" " " " ,,2 "
Sevêral ossa epiptel'ictl, "" " " " 2
A spheno-parietal sllture is mostly fOllncl at the sicle opposite to
the fL'ontal pl'ocess '(in 8 of 19 cases). This sutUl'e is not always
situatecl in the same place. U sually iL lies at the level of the su tura
j
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637
sqnamosa, 80 that the l'egion of the fl'ontal process is inc1uded in
the alisphenoïd.
Sometimes the spheno-parieta1 sutUl'e lies at the le\'el of the 10we1'
border of the frontal process; so that the region of this process is
iocl uded in the parietaJ. Tbe region of tbe frontal pl'ocess of Olle
side cao be incillded in the frontal, as is pl'oved by a skull, which
pJ'esents at the 1eft side a ti'ontal procesfl of the tempo ral and at
the right side a symmetrical temporal process of the frontal.
If at the side opposite to the frontal process one Ol' more ossa
epiptel'ica are found, the situation cand extension of these bones are
equal Jo those of the ti'ontal process.
We find other relations in the skulls with frontal proces sus of the
second type. Here the enlal'gemeu't of the squamosal is nearly always
absolutely sJ mmetrical.
Only once did I find a second type of fl'ontal procees at one side
and an ós epiptericum typicum at the othel' one.
I suppose th at the question aftel' genesis and significance of the
above mentioned two (ypes of ti'ontal processus must be answel'ed
as follows.
The proc. fi'ontalis of the first type is to be considereà as the
homologon of an os epiptel'icUlll typicum. Following arguments led
me to this opinion.
In the fil'st place it is possible that the l'egion of a unilatel'al
proc. - frontalis can be included at the opposite side in one of the
surl'ounding bon es (sphenoid, f1' on tal, parietai),
In the second place it must be remembered that the ossa epipterica,
which are pl'esent at the side opposite to the frontal process, COl'respvnd
in their extension and sitnation to this process.
When we find a frontal process together with all os epipte~
ricum at the opposite side, these two cOl'l'espoJld with the fl'ontal
pl'ocess: .
At last I have to mention the great val'iability in form and
extension of the proc. ft·ontalis. As 1 wil! explain flll'thel' on, we
can iind tha'! in a skull with a, unilatel'al os epiptel'icum Ol' ossa
epiptel'Ïca the opposite side SilOWS tbe same conditions as in a Skllll
with a unilateral processns ft'outalis of the th'st type.
The fl'ontal pl'ocess of the secol1l1 type, the enlargement of the
whole squamosal, conld be clue to two canses. In the first place we
can suppose that met'ely an enlargement of the sqllamosal is cause
of the exclusion of the alisphenoid from the frontal, in the sepond
plaC'e we can imagine tlmt this enhwgement is due to the opposition
(v Ihe squamosal of that part of the alisphenoicl which is not
41
Proceedings Hoyal Acad. Amslerdam. Vol. XVI.
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Ba8
èartilagineons pl'efol'med, viz. the os jntel'temporale ti'om RANKE 1).
Pel'haps both ways of enJa,l'gement of the temporal in forward
direction occur; only ontogenetical and compal'ative anatomical
investigations could make out this question.
Ossa epipte1 o ica.
I have brought the 08sa epiptel'ÏL'a to the fol1owing types.
1. Os epiptericnm bordering to fonr bones (fl'ontal, parietal,
temporal, alisphenoid): os epiptel'icum typicum.
Î;
U. Os epiptel'icum, bordering ro thl'ee bones.
a: fl'ontal, parietal, alü;phenoid: os epipt. anterius.
b: parietal, temporal, alisphelloid: os epipt. posterins
c: fl'Ontal, parietal, temporal : os epipt. supel'ius
cl: frontal, tempora!, alisphenoid: os epipt. inferins.
lIl. Os epiptericum, bordering to two bones; i. e. presenting itself
as a sutural bone.
IV. Sevel'al ossa epipterica.
Thirty times I found an os epiptel'icnm typicnm
In
4 slmlIs on both si des
,,15 " "the right side
,,11 " "the left side.
If an os epiptel'icnm typicuID is present on both sides of the
skull, the two bon es are sjmmeteical in situation and extension.
If an os epiptericum is only present at Olle side of the skuJl we
find, when examining the other side of the same skuJl the foIlowing
caseB:
1. Os epiptericnm typicum at the right side
a frontal process
a spheno-parietal sutUl'e "
a frontal proce5s and an os epiptel'icum "
Sevel'al ossa epipterica
H. Os epiptericum at the left side
a frontal process
at the left side in 4:' skulls.
" " ,. ,,5 ,)
" " " ,,3 "
" " " " " 2 "
at the right side in 2 skulls.
a spheno-parietal suture" " " ,," 6 "
Several ossa epipterica " " " "" 1 "
This survey proves that the side of the skull, opposite to nn os
1) RANKC. J. Uebet, den Stirnfortsalz del' Schliifenschuppe bei den Pl'Ïmaten,
Sltzungsbel'. bayl'. Aknd. d. Wissensch 1898.
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639
epÎptel'iCllm typicllm can show just the same condition as a sÎtllllwith
a nnilateral processus fl'ontalis of Lhe first type.
That in case of a uni1atel'a,l os epiptel'icllm typiCllID the l'ight
side is predominant to t!Je left one is dne to the predominance of
the fl'ontal pl'ocess of the first type on the 1eft side.
If at the side of the skull, opposite to an os epiptel'icum typicmn
a spheno-parietal sllture is fOllnd, then the same 1'ules hold for the
situation of this suture as by a unilateral frontal processj that part
of the Skllll that lies symmetl'ical to the ptel'Ïc bone can be inclllded
as weIl in the aJisphenoid as in the frontal Ol' pal'ietal bone.
n. I fOllnd an os epiptericum of the second type in 7 skulls; in
one on both sides anel symmetl'ical, in 5 on the l'ight and in one
on the left side. This pteric bone was always combined with a
fl'ontal process of the fb'st type. Fol' the composition of the ptel'ic
region of tbe opposite side of the Skllll in a llnilateral OCCl1l'l'ence
of such a pteric bone can be referred (0 the description of the
frontal process.
lIl. An os epiptel'icum of this type I fOllnd only ollee in a skull
as a little sutllral bOlle in a fronto-temporal slltl1l'e.
IV. Sevel'al oss a epipterica I observed in 4 sknlls; ahvays hvo
bone-pieces were present. In ::3 slmlIs they were on the l'ight j m one
on the left side.
Fol' tbe behaviollr of the side of the simIIs opposite to those
wiÓ1 two pteric bon es, I refel' to the descriptions befol'e mentioneel.
All in all I fOllnd ptel'ic bones in 42 &knlls, or 36.8 % that is
to say in 5 on both sides, in 23 on the l'ight and in 14 skuUs
on the left side.
This enumel'ation pl'oves that pteric bOlles are more of ten fOUlld
on the l'ight than on the left side, on the eontraiT the fusion of
the bone pieces in the pteric region with one of the surl'ounding
bones, specially the squamosal, happens more fl'equently on the left
than on the right side.
It is impossible to deeide by this stud)' the meaning of the
pteric bones.
The frequent occurrence of these separate bone.pieces in papuan~
simIIs is not favourable for RANKJi]'S theory, saying' they ought to
be eonsidered pathologica1.
Ontogenetical and comparative anatolllical researches will be
necessary to explain this question of the anatomy of human skull.
41*
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