close

Вход

Забыли?

вход по аккаунту

?

Observations on an unusual case of bilateral platysmo-pharyngeal muscular inter-connections in man.

код для вставкиСкачать
Observations on a n Unusual Case of Bilateral
Platysmo-Pharyngeal Muscular Interconnections in Man
HOWARD K. SUZUKI, DALE D. BRIGGS,' HOYTE R. PYLE, JR.: BETSY
0. WALLOCH' AND M. CAROLYN WILSON'
Department of Anatomy, University of Arkansas Medical Center,
LittEe Rock, Arkansas
The present article is a description of
two related bilateral muscular anomalies
associated with the pharynx, and as far as
could be ascertained, these are unlike any
previously reported (Bardeen, '25; Bovero,
1895; Curnow, 1874; Perrin, 1871; Piersol,
'23; Ruge, '10, '11; Seydel, 1894; Testut,
1884).
cleidomastoid muscle and were at first considered to be part of it. The muscle fibers
then coursed craniad in a postero-lateral
direction paralleling the sternocleidomastoideus. Superficial to the bifurcation of
the common carotid artery, the direction
of the muscle fibers changed. In this
area, the muscle was inferior to the tenDESCRIPTION
dinous part of the digastric muscle. The
The cadaver reported herein was a male superior superficial part of the muscle
Negro known to be 75 years old at the was attached along the inferior border of
time of death. No case history of any the body of the mandible and radiated
kind was available and no acquaintances cranially in the subcutaneous tissue of
could be located; therefore, no facts are the lower facial region. The muscle
available concerning the living individual.
coursed infero-posteriorly along the neck
The body was presented for routine disuntil it joined the inferior superficial part
section in a course in gross anatomy.
In passing, it should be mentioned that of the muscle.
The two superficial parts of the muscle
there was a unilateral sternalis muscle
on the left side and enlarged ventricles then coursed deeply in a cranio-posterior
in the brain, without concomitant abnor- direction, being crossed superficially and
mal external appearance of the cranium. inferiorly by the hypoglossal nerve, and
The first muscular anomaly to be de- then coursed between the external carotid
scribed had its superficial attachments at artery anteriorly and the ascending pharthe sternal manubrium and the body of yngeal and internal carotid arteries
the mandible. These superior and infe- posteriorly. The deeply coursing muscle
rior muscular slips joined deep to the fibers were posterior to the insertion of
sternocleidomastoideus and inserted into the stylohyoid muscle. The muscle then
the pharynx (figs. 1 and 2). They did passed between the superficial and deep
not form a broad flat muscular sheet as portions of an anomalous stylopharynis usually the case with the platysma; geus muscle. A description of the latter
thus the name platysmo-pharyngeus was will be given later in this paper. After
inappropriate. Therefore, we have named passing between the superficial and deep
the muscle, manubrio-mandibulo-pharyn- portions of the stylopharyngeus, it inserted into the median raphe of the phargeus.
As for the superficial portions of the ynx. A large part of the anomalous musmuscle, the inferior part was attached cle functionally and anatomically took
at the postero-superior part of the sternal the place of the middle constrictor. Some
manubrium, medial to the origin of the of the inferior fibers coursed immediately
sternocleidomastoid muscle. The muscle
1 Investigation carried out during their tenure
fibers were closely adherent to the sterno- as first year medical students.
93
94
HOWARD K. SUZUKI AND OTHERS
over the greater cornu of the hyoid bone
and antero-medial to the superior cornu
of the thyroid cartilage, and finally interdigitated infero-posteriorly with the fibers
of the inferior constrictor in the median
raphe.
The manubrio - mandibulo - pharyngeus
muscle was essentially similar on both
sides except that the manubrial slip was
more extensive in thickness and breadth
on the left side, while the slip from the
mandible was larger on the right. There
was no evidence of the usual subcutaneous course and direction of platysma
fibers over the sternocleidomastoid, posterior triangle of the neck, infrahyoid region or pectoral region.
The second muscular anomaly concerned the stylopharyngeus muscle. For
descriptive purposes it will be subdivided
into deep and superficial parts (fig. 2 ) .
The deep portion of the muscle had the
more normal relations in that it originated in the usual position on the medial
side of the base of the styloid process and
descended deep to the middle constrictor.
(In this case the manubrio-mandibulopharyngeus.) The insertion of the deep
portion of the stylopharyngeus differed
from the usual description in the anatomy
texts. On the right side, the muscle dissipated into the pharyngeal musculature.
On the left side, the major portion of the
muscle inserted into the pharyngeal wall,
but one large slip inserted into the
greater cornu of the hyoid bone.
The attachments of the superficial portions of the stylopharyngeus differed on
the two sides. The right side originated
from the base of the styloid process, while
the left originated from a ridge between
the styloid process and the lateral wall of
the carotid canal. Both superficial portions descended postero-medially and
coursed superficially (posterior) first to
the superior constrictors and then superficial to the manubrio-mandibulo-pharyngeus. They inserted in the area of the
Fig. 1 Anterior view of the neck region showing the deep relationship of the manubriomandibulo-pharyngeus to the sternocleidomastoideus.
OF MANUBRIO-MANDIBULO
INF. CONSTRICTOR M.
VAGUS N.
CERVICAL SYMPATHETIC TRUNK
SUP CORNU OF THYROID
GREATER CORNU OF
-
\x
Fig, 2
x
OF MANDIBLE
SUPERFICIAL PART OF
STYLOPHARYNGEUS M.
STYLOID PROCESS
RAMUS
EXTERNAL JUGULAR V
INTERNAL JUGULAR V
HYPOGLOSSAL N .
EXTERNAL CAROTID A.
ASCENDING PHARYNGEAL A
FACIAL A.
~ L O S S O P H A R Y N G E A N
L
Posterior view of the pharynx showing the relationships of the aberrant
manubrio-inandibulo-pharyngeus and stylopharyngeus muscles.
-’
MANUBRIAL SLIP OF MANUBRIO- MANDIBULOPHARYNGEUS M.
COMMUNICATION OF MANUBRIO- MANDIBULOPHARYNGEUS M.
PHARYNGEAL PORTION OF MANUBRIO-MANDIBULO
PHARYNGEAL M.
SUBMANDIBULAR GLAND
MANDIBULAR SLIP
PHARYNGEAL M.
DEEP PART OF STYLOPHARYNGEUS M
STYLOHYOID M
SPINAL ACCESSORY N
SUP. CERVICAL GANGLION
SUP CONSTRICTOR M
POST BELLY OF DlGASTRlC M (retracted 1
STERNOCLEIDOMASTOID M.
A
PHARYNGOBASILAR FASCIA
2
96
HOWARD K. SUZUKI AND OTHERS
median raphe, and fasciculi from each
crossed and became continuous with the
fibers of the inferior constrictor on the
contralateral side.
The manubrio - mandibulo - pharyngeus
and anomaIous stylopharyngeus appeared
to be innervated by the glossopharyngeal
nerve. In addition, the superficial portion
of the manubrio - mandibulo - pharyngeus
received branches from the cervical portion of the facial nerve. While no nerve
was found to innervate the manubrial
portion of the muscle, it may have been
innervated by the spinal accessory nerve,
because of the muscle’s close relationship
to the sternocleidomastoid.
The most apparent relations disturbed
by the muscle were those of the external
carotid artery and glossopharyngeal nerve.
The former was pulled anteriorly from
its normal position, as the manubrio-mandibulo-pharyngeus passed between it and
the internal carotid artery. The latter
passed postero-inferior to the superficial
stylopharyngeus muscle and gave it a
large branch, coursed anteriorly caudal to
the communicating fibers of the manubriomandibulo-pharyngeus, sent a branch to
the deep part of the stylopharyngeus, and
finally followed its usual course to the
tongue.
DISCUSSION
Connections of the platysma to the deep
neck musculature are rare. The primary
muscular variation described in this paper
originates, on each side, from the mandible and manubrium and inserts in place
of the middle constrictor, and is not similar to previously described examples. The
muscle described by Bovero (1895), Curnow (1874), Perrin (1871), and Ruge
(’10) originated in the occipital region,
and would appear to represent an atavism
of the platysma of lower mammals. In
higher mammals the nuchal portions usually degenerate, while the anterior fibers
become more highly developed (Huber,
’31). A small vestige of the occipital portion of the platysma is often present in
man although it is not necessarily connected with the more anteriorly placed
platysma (cf. fig. 14, Huber, ’31). In the
present .example, the deep connections of
the anteriorly attached fibers appear to
represent an even more advanced evolu-
tionary stage in the possible deep connections with the pharynx.
The interesting fact concerning the
deep connection of the “platysma” in the
present report is that the communicating
fasciculi on each side become continuous
with fibers of the middle constrictors.
This is quite distinctive as the middle
constrictors ordinarily arise from the
greater cornu of the hyoid bone (Blount
and Lachman, ’53; Goss, ’59). Both Perrin
(1871) and Curnow (1874) reported that
their muscular anomalies blended into the
inferior constrictors, while Bovero (1895)
observed that his muscle passed to the
stylopharyngeus and superior constrictor.
The muscle observed by Ruge (’10) ended
in relation to the posterior belly of the
digastric on one side and blended into
the pharynx in close relation to the stylopharyngeus on the other side.
The interconnecting fibers of the manubrio-mandibulo-pharyngeus muscles pass
between the two portions of the stylopharyngeus on each side. The deep portion of the stylopharyngeus should not be
misconstrued to be a separate slip of the
stylohyoideus, as it is innervated by the
glossopharyngeal nerve.
The development of these anomalies
presents an intriguing problem. It appears
that the critical period for their formation
was between the fifth and ninth week of
gestation. In the 5th week, the branchial
arches are visible. By the 6th and 7th
week, the second visceral arch has grown
caudally, burying the third and 4th arches
forming a triangular depression called the
cervical sinus (Keith, ’49). Meanwhile
the aortic arches are transforming into
the definitive arteries. In the latter part
of the 8th week, the branchial muscles
become differentiated (Keith, ’49). The
mandibular portion of the manubrio-mandibulo-pharyngeus was probably derived
from the mesenchyme of the second visceral arch, while the pharyngeal (middle
constrictor) part of the manubrio-mandibulo-pharyngeus and stylopharyngeus
were derived from the third visceral arch.
The manubrial part was possibly derived
from the splitting of the sternocleidomastoid muscle, which is considered to be of
visceral arch origin, possibly the second
and third visceral arches (Keith, ’49) or
PLATYSMO-PHARYNGEAL ANOMALY IN M A N
the caudal arches (Arey, '54). When the
muscles were differentiating in the latter
part of the 8th week, the cervical flexure
was still prominent; therefore, the visceral arches were closely approximated.
Likewise the cervical sinus would have
disappeared by this time (Keith, '49) and
the external carotid arteries would have
already formed as outgrowths of the third
aortic arches (Congdon, '22). It would
seem then, that the muscles derived from
the different visceral arches may have
fused to form the interconnecting fibers
of the manubrio - mandibulo - pharyngeus
muscle during this period. This would
account for the observed relationships of
the communicating fibers of the anomalous muscles between the external and
internal carotid arteries. In addition, the
topographic relations of these same fibers
were located in the vicinity of the carotid
triangle, which according to Frazer ( ' 2 6 ) ,
is the definitive location of the second and
third visceral arch derivatives.
SUMMARY
A deep bilateral muscular interconnection between the platysma and the middle
constrictor, which was called the manubrio - mandibulo - pharyngeus, and a
doubled stylopharyngeus muscle are described. These were observed in an adult
cadaver during routine gross dissection.
The manubrio - mandibulo - pharyngeus
muscle is unusual since these communications arose from anteriorly originating
muscle fasciculi. Previous reports of deep
interconnections of the platysma were observed to take place from the occipital
portion of the platysma. The anomalous
muscles may have fused during the 5th
through the 8th week of gestation while
the visceral arches were closely approximated.
97
ACKNOWLEDGMENTS
We gratefully acknowledge the helpful
suggestions and criticisms given us by
Doctors H. N. Marvin and A. W. McCullough, and to Mr. Jack Diner for his careful work on the illustrations.
LITERATURE CITED
Arey, L. B. 1954 Developmental Anatomy, 6th
ed. W. B. Saunders Co., Philadelphia, chap.
XXI, pp. 426-438.
Bardeen. C. R. 1925 The musculature. In:
Morris' Human Anatomy, 8th ed., C. M. Jackson, ed. P. Blakiston's Son and Co., sectionV,
pp. 353-547.
Blount, R. F., and E. Lachman 1953 The digestive system. I n : Morris' Human Anatomy,
11th ed. J. P. Schaeffer, ed. The Blakiston Co.,
New York, section X, pp. 1291-1424.
Bovero 1895 (quoted by Ruge, 1910).
Congdon, E. D. 1922 Transformation of the
aortic arch system during the development of
the human embryo. Carneg. Inst. Contrib.
Embryol., 68: 49-110.
Curnow, J. 1874 Notes on some muscular irregularities. J. Anat. Physiol., 8: 377-379.
Frazer, J. E. 1926 Disappearance of the precervical sinus. J. Anat., (Lond.), 61: 132-143.
Goss, C. M. 1959 Gray's Anatomy, 27th ed.
Lea and Febiger, Philadelphia, pp. 1207-1314.
Huber, E. 1931 Evolution of Facial Musculature and Facial Expression. Johns Hopkins
Press, Baltimore, pp. 184.
Keith, Sir A. 1949 Human Embryoloqy and
Morpholoav. Edward Arnold and Co., London,
chap. XVIII, pa. 343-363.
Perrin, J. B. 1871 On a peculiar additional
digastric muscle. J . Anat. Physiol., 5: 251256.
Piersol, G . A. 1923 Human Anatomy. J. B.
Lippincott Co., Philadelphia, pp. 454-672.
Ruge, G. 1910 Verbingdungen des Platvsma
mit der tiefen Muskulatur des Halses beim
Menschen. Morph. Jb., 41: 708-724.
1911 Ein Rest der Verbingung des
Platysma mit der tiefen Muskulatur des Halses
beim Menschen. Ibid., 43: 335-337.
Seydel, 0. 1894 Ueber eine Variation des
Platysma Myoides des Menschen ein Beitrag
zur Morphologie dieses Muskels. Ibid., 21:
463-472.
Testut, J. L. 1884 Les anomalies musculaires
chez l'homme expliquhes par l'anatomie comparbe, Leur. importance e n anthropologie. G .
Masson, Paris, p. 884.
-
Документ
Категория
Без категории
Просмотров
0
Размер файла
384 Кб
Теги
connection, observations, pharyngeal, case, intel, unusual, man, bilateral, muscular, platysmo
1/--страниц
Пожаловаться на содержимое документа