Book - Handbook of Pathological Anatomy 2.2
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Meckel JF. Handbook of Pathological Anatomy (Handbuch der pathologischen Anatomie) Vol. 2. (1812) Leipzig.
- Ligaments: I. Trunk | II. Head | III. Extremities Muscles: I. Trunk | II. Head | III. Extremities Angiology: I. Heart | II. Body or Aorta Arteries | III. Body Veins| IV. Pulmonary Artery | V. Pulmonary Veins | VI. Lymphatic System | VII. A Comparison of Vascular System Nervous System: I. Central Nervous System
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Section II. Of the Ligaments of the Head
§ 844. The ligaments of the head are,
- The ligaments which unite the head to the vertebral column.
- The ligaments of the lower maxillary bone.
Chapter I. Of the Ligaments Between the Head and the Vertebral Column
( 1 )
§ 845. The head and particularly the occipital bone considered as a single bone articulated to the vertebral column, unites with the first and second cervical vertebrae, and with each differently. The peculiarities of the articulations between the first and second cervical vertebrae, have determined us to examine them separately and to describe them apart from the general ligaments of the vertebral column.
I. LIGAMENTS BETWEEN THE OCCIPITAL BONE AND THE ATLAS.
§ 846. The connection between the occipital bone and the atlas is less intimate than between the vertebrae. The intervertebral and the yellow ligaments do not exist ; they are, like the fibrous ligaments, replaced only by looser fibrous bands, which extend from the anterior and posterior arches lo the large occipital foramen, and are called the occipito-alloidal membranes.
(1) Mauchart, resp. Rumelin, Capitis articulatio cum prima et secundâ colli vertebra, Tubingen, 1747.
SYNDESMOLOGY,
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I. ANTERIOR OCCIPITO-ATLOIDAL MEMBRANE.
§ 847. The anterior occipito-atloidal ligament ( membrana annuli anterioris atlantis ) is, in fact, only the summit of the anterior vertebral ligament, and extends from the anterior arch of the atlas to the anterior edge of the large occipital foramen. It is formed of perpendicular fibres, of which those in the centre are stronger, and form a distinct and projecting fasciculus, which is continuous with the central and prominent portion of the anterior vertebral ligament (§821), arid is attached to the centre of the basilar process of the occipital bone.
II. POSTERIOR OCCIPITO-ATLOIDAL MEMBRANE.
§ 848. The posterior occipito-atloidal membrane ( membrana annidi posterioris atlantis ) is situated between the posterior extremities of the two articular ligaments, and extends from the upper edge of the posterior arch to the posterior part of the circumference of the occipital foramen, and fills the posterior space between the two bones. It is thinner and weaker than the anterior, and does not form a continuous membrane, as that does.
III. ARTICULAR LIGAMENTS.
§ 849. The articular processes of the occipital bone and of the atlas are united, like the articular surfaces of the transverse processes, by a complete capsular ligament ( Lig . articulationum capitis cum atlante, Lig. articulare superius), which arises from the circumference of their contiguous surfaces. It differs from the others in being broader and looser, so that it allows more extensive motions.
IV. ACCESSORY LIGAMENTS.
§ 850. The accessory ligaments {Lig, accessoria) are fibrous bands, which proceed obliquely from above downward, and from without inward, from the summit and from the upper edge of the transverse processes of the atlas, and are attached partly to the capsule and partly to the occipito-atloidal membranes, and around the occipital foramen. They strengthen the ligaments already described, and furnish points of attachment to the small deep muscles of the head.
II. LIGAMENTS BETWEEN THE BASILAR BONE AND THE AXIS.
§ 851. The union between the head and the axis by means of the basilar bone is much firmer and stronger than that between the head and the atlas. It is formed by very dense bands of longitudinal fibres, which extend from the edges of the occipital foramen to the centre of the axis. There are no capsular ligaments in this articulation.
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DESCRIPTIVE ANATOMY.
I. SUSPENSORY LIGAMENT OF THE SECOND CERVICAL VERTEBRA.
§ S52. The middle straight ligament, or the suspensory ligament of the second cervical vertebra(l) ( Lig . Suspensorium dentis epistrophœi, s. rectum medium ), is oblong and composed of straight fibres. It extends from the centre of the anterior edge of the occipital foramen to the summit of the odontoid process, to which it is attached directly above the small anterior articular fossa. It prevents the head from turning too far backward.
II. LATERAL LIGAMENTS OF THE SECOND CERVICAL VERTEBRA.
§ 853. The lateral ligaments of the second cervical vertebra (Lig. epistrophœi I at er alia, s. alaria JMaucharti) are one on each side, and arise some lines behind the suspensory ligament, from the anterior part of the lateral region of the occipital foramen, and from the rough fossa situated above the internal edge of the condyles of the occipital bone. Their fibres are oblique and are attached to the lateral edges of the odontoid process.
When the head is turned to one side the fibres of the lateral ligament of the opposite side are tense ; so that these ligaments limit the lateral motions of the head.
These three ligaments are the most important of those which unite the head with the first cervical vertebra. If one or all three of them be torn, the odontoid process is displaced by the least exertion, slips into the vertebral canal, suddenly compresses the origin of the spinal marrow, and thus occasions death. Hence death from hanging, and hence too, when the head is quickly turned to the side, or when it executes similar motions, the subject sometimes dies.
III. COMMON LIGAMENTS BETWEEN THE BASILAR BONE AND THE CERVICAL VERTEBRA
§ 854. The common ligaments between the basilar bone and the cervical vertebrae are of several kinds, and differ in form, situation, and extent. We may divide them into those which are situated within and those which are placed on the outside of the vertebral column.
(1) Scemmerring ( Banderieh', 'e , p. 17) has already remarked that Weitbrecht was
wrong in denying the existence of this ligament. In fact, we have always found it
perfectly distinct from the crucial ligament; so that we cannot agree with Wcitbrecht in thinking that anatomists have been induced by this branch to admit its
existence, since we have lound botli of them constantly, and they were separated by
a loose cellular tissue. This remark might seem superfluous, if Bichat had not
adopted Woitbrecht’s opinion. True, lie describes a special ligament between the
middle of the odontoid process and the basilar bone, but he is mistaken in stating it
to be formed by the upper branch of the crucial ligament and the suspensory ligament ; so that he deset ibes the crucial ligament as formed only of a transverse part
and of the lower branch, and even mentions a connection between its fibres and those
of the posterior ligaments of the vertebræ, although in fact they are separated by the
capsule of the crucial ligament (§ 857).
I. COMMON INTERNAL LIGAMENTS.
A. CRUCIAL LIGAMENT.
§ 855. Behind the ligament described we find another, which is weaker, called the crucial ligament ( Lig . cruciforme). It is also called the transverse ligament of the atlas (L. atlanlis transversale) ; this term is however improper, as it points out only one of its parts. It unites the basilar bone with the first two cervical vertebræ.
Its strongest transverse part, called the transverse ligament of the atlas , is formed of transverse fibres. It is attached by its two extremities to the rough lateral edge of the medullary foramen of the atlas. It is very tense, and is situated behind the odontoid process : it is much broader in the centre than at its two extremities, and it is cartilaginous forward on the side of the posterior face of the odontoid process. Manchat has noticed this peculiarity, but he adds, that in this part the ligament does not adhere to the process but is only in contact with it. Bichat only has described the connection of this cartilaginous portion with the process ; he states that a synovial capsule exists between them. In fact we have constantly observed this capsule, which we have always found also very broad and very loose.
This transverse ligament forms the two horizontal branches of the cross. The two perpendicular branches of the cross, the upper and the lower, called also the appendages ( appendices ), arise from its centre; these are much weaker and are both formed of longitudinal fibres.
The upper branch is much longer than the lower, becomes much broader upward, and is not only attached behind the suspensory ligament, from which it is evidently distinct at the centre of the occipital foramen, but also extends some lines on the centre of the upper face of the basilar process of the occipital bone.
The inferior branch is much shorter than the other, and it is attached directly below the posterior articular facet of the odontoid process, which is smooth and not cartilaginous, to the upper part of the posterior edge of its base, which is considerably rough.
The use of this ligament is not merely to strengthen the connections between the three bones to which it is attached, but also to allow the atlas to rotate around the odontoid process as around an axis, in which the synovial capsule assists, and at the same time to protect the spinal marrow from the action of this process.
B. LIGAMENTOUS ENVELOP OF THE HEAD AND CERVICAL VERTEBEÆ.
§ 856. Behind the crucial ligament, between it and the posterior ligament of the vertebral column to which it is loosely attached, we find a broad layer of longitudinal fibres, which arises from the upper face of the basilar process of the occipital bone and descends to the third or fourth cervical vertebra. This layer unites above with the dura mater and below with the posterior bridge of the vertebra. It is called the lig amentous envelop of the cervical vcrtebrce ( apparatus vcrtebrarum colli ligamentosus).
II. COMMON EXTERNAL LIGAMENT BETWEEN THE HEAD AND THE CERVICAL VERTEBRA.
§ 857. The common external ligament between the head and the cervical vertebra is the cervical ligament ( Lig. nucha s. cervicis), which begins at the spinous process of the seventh cervical vertebra, whence it extends to the posterior occipital spine and to its upper curved line. This ligament is thin and perpendicular, and gradually enlarges as it approaches the head. Its upper edge is thicker, it being formed of the united tendons of the muscles of the neck. It is continuous between the cervical vertebra with the interspinal ligaments, and its posterior edge represents the supraspinal ligaments.
IV. LIGAMENTS BETWEEN THE FIRST AND SECOND CERVICAL VERTEBRÆ.
§ 858. Beside the posterior ligament and the two common capsular ligaments, which are looser here than in the rest of the vertebral column, the anterior face of the odontoid process unites also with the centre of the posterior face of the anterior arch of the atlas by a loose capsular ligament.
Chapter Ii. Of the Ligaments of the Lower Maxillary Bone
§ 859. The ligaments of the lower maxillary bone are, 1st, those which unite it with the temporal bones ; and, 2d, those between it and the hyoid bones.
I. Ligaments of the Temporo-Maxillary Articulation
§ 860. The temporo -maxillary articulation is formed by an interarticular cartilage , two synovial capsules , and by accessory fibrous ligaments.
I. INTERARTICULAR CARTILAGE AND SYNOVIAL CAPSULES.
A. INTERARTICULAR CARTILAGE.
§ 861. The inter articular cartilage ( operculum cartilagineum ) belongs to the class of fibro-cartilages ; it is oval, situated horizontally, with concave surfaces, and much thinner in its centre than at the edges. There is often in its centre a cavity filled by synovial membranes, which are then directly united. Its circumference is attached only to these membranes, and its external edge slightly adheres to the fibrous ligaments.
This fibro-cartilage diminishes the friction between the articular surfaces of the two bones.
R. SYNOVIAL CAPSULES.
§ 862. One of the two synovial capsules ( ligamenta cartilaginis intermedia) is situated above and the other below the interarticular cartilage.
The superior synovial capsule arises from the anterior edge of the transverse articular tubercle and from the posterior edge of the articular cavity of the temporal bone, and is attached to the circumference of the interarticular cartilage. It unites above with the cartilaginous covering of the articular surface of the temporal bone, and below with the upper face of the interarticular cartilage.
The inferior arises from the circumference of the maxillary condyle, and is attached to the edge of the interarticular cartilage, and unites partly with this cartilage and partly with the cartilage of the maxillary condyle.
These two capsules are very loose, and permit very extensive motions, especially upward and downward, since they are not confined forward or backward by fibrous ligaments.
II. FIBROUS LIGAMENTS.
§ 863. The firmness of the temporo-maxillary articulation depends on an external and an internal fibrous ligament.
A. EXTERNAL FIBROUS LIGAMENT.
§ 864. The external fibrous ligament ( membrana maxillae inferioris ) consists of very firm longitudinal fibres, which arise from the posterior extremity of the zygomatic process of the temporal bone, descend to the neck of the lower maxillary bone, and are attached to the outside and partly to the posterior part of the circumference of the synovial capsule. It is very tense when the jaw is moved forcibly forward or backward, so that it limits these two motions.
B. INTERNAL LATERAL LIGAMENT.
§ 865. The internal lateral ligament (Lig. maxilla laterale) should not be considered, properly speaking, as belonging to the temporo-maxillary articulation ; for it is situated at some distance from it and adds nothing to its firmness.
It is a thin, oblong, tendinous layer, arises from the spine of the sphenoid bone, and descends obliquely from above downward, from behind forward, and from within outward, to the lower maxillary bone, where it is attached below the internal orifice of the dental canal.
The vessels and the nerves of the lower maxillary bone pass between this ligament and its neck. Its principal use is, to enlarge those surfaces to which the two pterygoid muscles are attached, the outer part of which arises from them, and it is situated between their outer extremities.
II. LIGAMENTS BETWEEN THE SKULL, THE LOWER MAXILLARY BONE, AND THE HYOID BONE.
§ 866. In nearly the same direction as the ligament already described, but more deeply situated, we find a membrane which is thinner, slightly tense, and formed by condensed cellular tissue : this is strengthened only by some fibrous bands, which extend from the lower extremity of the styloid process of the temporal bone to the posterior edge of the angle of the jaw, and send a cylindrical slip to the small horn of the hyoid bone. This is the stylo-mylo-hyoid ligament {Lig. stylo-mylo hyoideum) : it serves partly to unite the temporal, the inferior maxillary and the hyoid bones, and partly to enlarge the surface to which the pterygoideus internus muscle is attached.
Chapter III. Of The Ligaments of the Hyoid Bones
§ 867. The body or the central portion of the hyoid bone articulates with the large and small horns by two synovial capsules ; one of them is narrow and tight, and the second is broad and loose. Both, but the first particularly, are strengthened by tendinous fibres.
The posterior extremity of the large horn is attached to the superior horn of the thyroid cartilage by a round perpendicular ligament, in the centre of which we often find a round cartilage or bone.
Meckel JF. Handbook of Pathological Anatomy (Handbuch der pathologischen Anatomie) Vol. 2. (1812) Leipzig.
Cite this page: Hill, M.A. (2024, April 24) Embryology Book - Handbook of Pathological Anatomy 2.2. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Book_-_Handbook_of_Pathological_Anatomy_2.2
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