Book - Handbook of Pathological Anatomy 2.1
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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 I. Of the Ligaments of the Trunk
§ 819. The ligaments of the trunk are divided into those of the vertebral column , of the ribs, and of the sternum.
Chapter I. Ligaments of the Vertebral Column
§ 820. The vertebrae are attached to one another in all parts of their surfaces by fibrous or fibro- cartilaginous ligaments, and in some parts by capsular ligaments also; the former serve to retain these bones in their places and to confine their motions, while the latter facilitate their motions, but are also covered externally by fibrous ligaments.
The principal ligaments of the vertebral column are, 1st, the intervertebral fibro-cartilages , which are of all the modes, the strongest bonds of union ; 2d, the synovial capsules , situated between the articular processes and which facilitate their motions.
These two kinds of ligaments are strengthened, as in all parts, by fibrous fasciculi, placed directly upon them, or which are attached to the other parts of the vertebral column. These fasciculi are the anterior and the posterior vertebral ligaments, the accessory fibres of the capsular ligaments, the yellow ligaments, the interspinal , and the intertransverse ligaments.
We had better consider first the fibrous and fibro-cartilaginous ligaments, and then tire synovial capsules.
I. FIBROU8 AND FIBRO-CARTILAGINOUS LIGAMENTS.
I. BETWEEN THE BODIES OF THE VERTEBRAE.
A. ANTERIOR VERTEBRAL LIGAMENT.
§ 821. The anterior vertebral ligament ( fascia longitudinalis anterior , ligamentum corpcrribus vertebrarum commune anterius ) covers the anterior and convex face of the bodies of the vertebræ. It extends from the centre of the anterior part of the large occipital foramen which Weitbrecht has wrongly disputed, to the last bone of the coccyx.
It is composed of longitudinal fibres which do not extend uninterruptedly from one extremity of the column to die other, but cover in fact only a single vertebra, and which unite above and below on the
surface of the intervertebral ligaments with those of the adjacent vertebrae.
The fibres are thicker on the vertebra than in any other part ; they grow thinner and shorter as they approach the upper and lower faces of the bone. Hence the anterior surface of the vertebral column is more uniformly convex than it would be without this arrangement, since the bodies of the vertebrae are concave from above downward.
Besides the straight fibres, we also find many which are oblique ; these cross the former at a very acute angle.
This ligament is thicker, and its fibres are much closer in its centre
than on tha sides. The fibres separate very much from each other on
the two sides of the median line, while on the contrary they unite
backward so that they form three bands, the central of which is the
strongest while the two lateral bands are weaker.
The ligament covers all the anterior face of the bodies of the vertebræ ; it is not confined to the centre and to sending only irregular prolongations to the sides. Its lateral parts are composed of longitudinal fibres as regular as those of the central portion ; and they differ so little in their essential characters from the periosteum, that the ligament may be regarded as a periosteum more developed. We cannot at least refuse it this character in most of the vertebral column, especially in the dorsal, the lumbar, the sacral, and the coccygæal regions. In the cervical vertebrae, especially the upper two, the anterior ligament assumes still more the appearance of a very thick, rounded, and very projecting band, which covers only the centre of the anterior face, while the fibres on the lateral parts of the bodies are thin and irregular. This difference doubtless exists because the anterior face of the cervical region is covered with muscles, which are not found in the other regions of the vertebral column. The lateral part of the anterior ligament in these last, appears in the neck as the tendons of the anterior muscles of the neck. So too on the second lumbar vertebra, this ligament becomes the tendons of the diaphragm.
The narrowness of the anterior ligament on the upper cervical vertebras depends upon the great degree of motion possessed by these bones, and being formed in this manner their motions are not so much obstructed.
This ligament is not equally thick on all the vertebrae. Its thickest parts cover the upper cervical and dorsal vertebrae, the thinnest are found on the superior lumbar vertebrae.
It not only unites the bodies of the vertebrae forward, but also prevents the column from bending too much backward.
B, POSTERIOR VERTEBRAL LIGAMENT.
§ 822. The posterior vertebral ligament ( fascia , s. ligamentum commune posterius ) extends along the posterior face of the bodies of the vertebrae, within the medullary canal.
It diminishes in breadth from above downward ; in the cervical vertebrae it is as broad as the bodies of the vertebrae ; it is much thinner on the sides in the dorsal vertebrae, and finally disappears entirely in the lumbar regions, becoming a single waving band situated on the median line, being a little broader on a level with the upper and lower faces of the bodies of the vertebrae.
At the same time, it is attached to the intervertebral substance more firmly than to the posterior face of the bodies of the vertebrae.
Its relations with the vertebrae and with the dura mater are not exactly the same. In most of the vertebral column it is intimately
connected with the bodies of the vertebrae, and it is attached to the dura
mater only by a loose mucous tissue. But at the third cervical vertebra its relations with these vertebrae change, since the ligaments extending from the head to the cervical vertebrae form, between it and
their posterior faces, a peculiar fibrous mass, the fibrous mass behveen
the head and the cervical vertebræ, to which that ligament adheres
but very slightly as far as the upper extremity cf the vertebral column.
In its first portion, it unites as usual to the dura mater ; but at the upper extremity of the vertebral column it is so closely connected with this membrane that some skill is required to separate them ; hence the separation between the fibrous membrane of the central portions of the nervous system and the largely developed periosteum of the vertebræ begins in this place.
In the same place the posterior vertebral ligament unites intimately with the fibrous mass between the head and the cervical vertebræ.
This ligament limits, to a certain extent, the flexion of the vertebral column forward.
C. INTERVERTEBRAL LIGAMENTS.
§ 823. The intervertebral ligaments (Lig. intervcrtebralia) are the principal means of uniting the bodies of the vertebræ, and the vertebræ generally ; for the attachments of these bones in other parts, are much looser and much less extensive.
These ligaments completely fill the spaces between the bodies of the vertebræ ; they form layers, the upper and lower faces of which are attached to the corresponding faces of two superimposed vertebræ.
They are formed of a considerable number of perpendicular and almost concentric layers, shaped like the circumference of the upper and lower faces of the vertebræ, and they are consequently annular. Their two edges are attached to the two faces of the vertebræ. Their layers are evidently fibrous ; in the external layers the fibres aie oblique, and almost horizontal in the internal. The oblique fibres of the external layers cross at acute angles. The layers adhere very firmly together by the fibres which extend from one to the other ; hence they form only a single dense scaly tissue.
Between the layers we find a softer, yellowish, gelatinous, and shapeless mass.
The nature, the relations, and the proportional quantity of these two substances, differ in all parts of the ligament.
In the circumference, and especially in its anterior portion, the layers much exceed the intermediate substance ; they are very compact and are evidently fibrous. Internally, they are much softer ; they separate from each other and finally disappear entirely, so that the nucleus, formed by the gelatinous substance, only remains. In what ever direction the vertebral ligaments are cut, this nucleus projects from the incision, being pushed out, by the elasticity of the fibrous layers.
These ligaments are thicker in the centre than on the circumference, because the bodies of the vertebrae are concave in this place.
They are very solid, so that the bones of the vertebral column will break before they tear.
From their great elasticity, the height of man varies at all periods of life, and diminishes or increases according as the vertebral ligaments have been for a longer or shorter time pressed down by the weight of the head and that of the vertebras upon each other ; hence man is taller in the morning than at night. This difference is not the same at all ages ; it is less evident in old than in young men. In general it amounts to about one inch.(l)
The intervertebral ligaments have not the same thickness in all parts. It diminishes from the cervical vertebræ to the lower extremity of the vertebral column, whence there is a difference in this respect of several lines. Between the lumbar, these ligaments are only three or four lines thick.
§ 824. There are no intervertebral ligaments between the first and second cervical vertebræ, nor between the first and the head, between the sacrum and the coccj^x, nor between the bones of the coccyx ; these bones are united in a looser manner.
§ 825. The intervertebral ligaments are strengthened directly by anterior and posterior vertebral ligaments (§ 822, 823), which cover most of their circumference, and pass before them in going from one vertebra to another.
IX. or THE FIBROUS AND FIBRO-CARTIL AGINOUS LIGAMENTS BETWEEN THE ARCHES AND THE PROCESSES.
A. YELLOW LIGAMENTS.
§ 826. The arches of the vertebræ are united by the yellow ligaments ( Lig . crurum vcl arcuum subfiava , s. flava), as their bodies are connected by the intervertebral ligaments. These two kinds of ligaments may then be compared to each other.
The yellow ligaments are yellowish, lustreless, and smooth ; they are formed of several perpendicular and very elastic fibres, of which the external are evidently of a tendinous nature. These external fibres, which have a more oblique direction, fill all the space between the arches of two adjacent vertebræ, from the roots of the transverse processes to the angle of union, which however remains unattached.
Their upper edge is always attached to the internal face, and never to the inferior edge of the arch of the vertebra above. The inferior is attached to the upper edge, and slightly to the external face of the arch of tho vertebra below. The vertebra are rough where these ligaments are inserted.
(1) Mem. de Paris, 1725, 1730.
The thickness, solidity, and elasticity of these ligaments are very considerable.
They fix the extent of flexion forward and backward in the vertebral column.
They are not perfectly similar in all parts of the spinal column. The smallest are in the dorsal region, those in the neck are larger, and the largest in the lumbar region. Those in the lumbar region are the thickest, and the thinnest are those of the cervical region. Their insertions also vary in extent in the different regions ; in the neck they are attached by a thin upper edge to a very narrow portion of the internal face of their arches, above their inferior edge. In the back and loins, this portion is a very broad surface, almost as high as the ligaments, and extends from the centre of the arches to their inferior edge.(l) These differences are worthy of remark, first, because anatomists have hitherto neglected the second ; secondly, because they serve to increase the power of the lower portions of the vertebral column and the mobility of its upper portions.
The yellow ligaments do not exist between the first and the second cervical vertebrae, nor between the first cervical vertebra and the occipital bone, or at least they are developed very feebly in these two parts.
B. IN TE BSP INAL MEMBRANES AND 0UPBAS PINAL LIGAMENTS.
§ 827. Between the spinous processes we find two kinds of fibrous ligaments, the inter spinal membranes ( membrance inter spinales), and the supraspinal ligaments (Lig. inter apices processuum spinosorum).
a. Interspinal membranes.
§ 828. The interspinal membranes are thin and broad, and are formed of irregular, and generally of horizontal fibres. They extend from the roots of the spinous processes to near their summits. They limit flexion forward and are destined especially for the insertion of the long muscles of the back.
b. Supraspinal ligaments.
§ 829. The supraspinal ligaments are small rounded bundles of longitudinal fibres, which attach the summits of the spinous processes of the vertebrae to each other, so as to form in fact but one ligament. They also serve to limit flexion forward.
(1) Weitbrecht is mistaken in saying of these ligaments (loc. cit. page 107), Margines prœdic/.orum crurum viz sensibiliter super scandunt , since they are every where attached much higher than the lower edge, and none of their fibres are inserted in the vertebrœ of the neck.
C. INTERTRANSVERSE LIGAMENTS.
§ 830. The intertransverse, ligaments ( Lig . recta processmim transv.ersalium v er lehr arum, s. inter transversaria) do not every where exist. They are found only between the transverse processes of the inferior dorsal vertebrae forward. They serve not so much to unite the vertebrae as to multiply the points of attachment for the sacro-lumbalis and the levatores costarum muscles.
II. CAPSULAR LIGAMENTS.
§ 831. We find on each side, between every two vertebrae, a capsular ligament, the ligament of the articular processes {Lig. capsulare processum obliquorum ) ; this arises from the circumference of the articular faces of the adjacent oblique processes by irregular bundles of fibres. In the dorsal and lumbar regions this ligament is strengthened anteriorly by the yellow ligaments.
These ligaments have not the same extent in every part. They are much looser and less tense in the neck ^han in the other parts of the vertebral column. The broadest, the thinnest, and the loosest, is that between the first and second cervical vertebrae.
Chapter II. Of the Ligaments of the Ribs
§ 832. The ligaments of the ribs are divided into three classes :
1st. Those situated between the ribs and the vertebrae.
2d. Those situated between the ribs and the sternum.
3d. Those which exist between the ribs.
I. LIGAMENTS BEWEEN THE RIBS AND THE VERTEBRAL
§ 833. The ligaments between the ribs and the vertebrae, are some of them synovial capsules, and others supplementary fibres, which unite the posterior parts of the ribs with the bodies and the transverse processes of the vertebrae.
A. LIGAMENTS OF THE HEADS OF THE RIBS.
§ 834. The ligaments of the heads of the ribs {Lig. capitulorum costarum ) are short capsules, which extend from the lateral articular facets of the dorsal vertebrae to the heads of the ribs. These capsules are strengthened in front by the oblique fibrous ligaments, which have two different directions ; the upper go from within outward, and from above downward, and the inferior in the opposite direction.
D. LIGAMENTS OF THE TUBERCLE, AND THE EXTERNAL TRANSVERSE LIGAMENTS OF THE RIBS.
§ 835. Short synovial capsules arise from the anterior face of the summits of the transverse processes of the dorsal vertebræ, and go to the circumference of the articular surface of the tubercles. These capsules are looser in the lower than in the upper ribs.
The quadrangular ligaments ( ligamenta transversaria costamm externa) are situated on them posteriorly, and proceed from the summits of the transverse processes of the vertebræ : they are formed of very strong, more or less transverse fibres. These ligaments are narrower from above downward than from without inward, and are longer in the inferior than in the superior vertebræ. Their fibres descend to the upper and ascend to the lower ribs, from the transverse processes of the vertebræ.
They serve to strengthen the articulations of the ribs with the vertebra.
C. INTERNAL LIGAMENTS OF THE NECKS OF THE RIBS.
§ 836. The internal ligaments of the necjks of the ribs, or the internal transverse ligaments ( Li g . cervicis costarum interna s. transversaria interna ) do not extend, like the former, from the vertebræ to the ribs, which are articulated with them ; but from the inferior edge of the transverse process of the vertebra above, to the neck of the rib below. They are formed of fibres, which proceed obliquely from above downward, and from without inward. Their form is rhomboidal, and they are thinner and more feeble than the former.
D. EXTERNAL LIGAMENTS OF THE NECKS OF THE RIBS.
§ 837. The external ligaments of the necks of the ribs (Lig. costarum cervicis externa) are situated opposite the internal, and are composed of fibres which proceed in an opposite direction, and also extend from the transverse processes of the vertebræ to the necks of the ribs next below. They are scarcely apparent, or in fact do not exist, between the two upper and the two lower ribs.
E. ACCESSORY LIAGMENTS OF THE RIBS.
§ 838. The accessory ligaments of the ribs (Lig. acccssoria coslarum ) are rounded bands situated beyond the articular heads, which, descend from the transverse processes of the vertebræ to the posterior extremities of the bodies of the ribs.
II. COSTO-STERNAL LIGAMENTS.
§ 839. The ribs unite to the sternum by the costal cartilages, in part directly, in part indirectly.
The cartilage of the first rib is attached to the handle of the sternum,
and those of the other six true ribs unite to the articular depressions of
this bone by very short capsular ligaments, on which pass strong
tendinous fibres united to the periosteum. These ligaments radiate
and extend very far, particularly on the anterior face of the body, so
that those of one side intercross with those of the side opposite.
HI. INTERCOSTAL LIGAMENTS.
§ 840. If we except some tendinous fasciculi of the intercostal muscles which are situated between the bony portions of two adjacent ribs, and which are continuous posteriorly with the intertransverse ligaments of the vertebrae (§ 830), only the costal »cartilages are united by particular and constant ligaments. These ligaments are arranged in two ditferent ways.
A. ARTICULAR LIGAMENTS OF THE COSTAL CARTILAGES.
§ 841. The fifth, sixth, seventh, and eighth costal cartilages are united by synovial capsules, on which are strong fibres passing obliquely from above downward, and from without inward. Instead of these capsules, we find between the two following ribs only short tendinous fibres ; and between the last ribs only the fibres of the intercostal muscles, and of the obliqui abdominis muscles.
B. FIBROUS LIGAMENTS OF THE COSTAL CARTILAGES.
§ 842. Narrower fibrous ligaments ( Li g . coruscantia) are situated perpendicularly or obliquely from above downward, ancrfrom without inward. They proceed forward, rarely backward, and unite together the costal cartilages, beginning with that of the third rib, except those of the four mentioned in the paragraph above.
Chapter III. Of the Ligaments of the Sternum
§ 843. Between the three pieces of the sternum is a fibro-cartilaginous mass formed of horizontal fibres, which go from before backward. This mass seldom disappears entirely, and never except at a very advanced age ; but it is effaced between the second and the third pieces more frequently than between the first and second. It may be compared with the intervertebral cartilages (§ 823).
On its surface, and also on the anterior and the posterior face of the
sternum, are expanded firm tendinous bands, which unite to form
membranous expansions termed the anterior and posterior sternal
membranes ( membrana ossiam sterni anterior et posterior).
The posterior sternal membrane is formed almost entirely of perpendicular fibres, which are connected with the fibrous bands coming from
the membrane of the costal cartilages, at the place where the latter
unite to the sternum.
In the anterior sternal membrane , on the contrary, we see only at its inferior portion and on the median line, a narrow band formed of longitudinal fibres which arise from the fibres of the membrane of the cartilages of the inferior true ribs. Most of its fibres are formed of fanlike expansions, the summits of which correspond to the insertions of the costal cartilages in the sternum, and intercross with those of the posterior face of the sternum, partially covering the longitudinal fibres from the same origin, and partly covered by them.
These two sternal membranes evidently correspond to the two ligaments of the vertebral column (§ 821,822). They should' then’, from analogy, be called the sternal ligaments.
Meckel JF. Handbook of Pathological Anatomy (Handbuch der pathologischen Anatomie) Vol. 2. (1812) Leipzig.
Cite this page: Hill, M.A. (2024, April 27) Embryology Book - Handbook of Pathological Anatomy 2.1. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Book_-_Handbook_of_Pathological_Anatomy_2.1
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