Bauhaus-Universität Weimar

Titel:
The Cyclopaedia of Anatomy and Physiology, vol. 2: Dia-Ins
Person:
Todd, Robert Bentley
PURL:
https://digitalesammlungen.uni-weimar.de/viewer/image/lit25760/351/
343 
BONES OF THE FOOT. 
with a synovial membrane, which is only a 
prolongation from that of the joint between 
the astragalus and scaphoid. 
The chief bond of union between the as¬ 
tragalus and os calcis is by means of the 
interosseous ligament (apparatus ligamentosus 
cavitatis sinuosœ, Weitbr.): this ligament oc¬ 
cupies the hollow which is manifest on the 
outside between the os calcis and the neck 
of the astragalus. It consists of a series 
of strong ligamentous fibres, which arise all 
along the inner part of the depression on the 
astragalus in a curved course, and descend 
vertically, or nearly so, to be inserted into 
the corresponding depression between the two 
articular surfaces on the os calcis. A con¬ 
siderable quantity of fat occupies this space, 
and covers this ligament, and is intermixed 
with its fibres. 
The bones forming the second row of the 
tarsus are articulated as follows :— 
The scaphoid or navicular bone is articulated 
with the three cuneiform, by means of the 
triple surface already described on the former 
bone ; to each division of which one cuneiform 
is adapted (cuneo-scaphoid articulation). A 
common synovial membrane lines the surface on 
the scaphoid, the surfaces of the cuneiform bones, 
and passes in between them to line the lateral 
articular facets on the latter bones. The three 
cuneiform bones are connected to the navicular 
by means of six ligaments, which pass from 
the former to the latter ; three on the dorsal 
surface and three on the plantar. The dorsal 
ligament of the internal cuneiform extends 
directly from behind forwards, those of the 
others proceed obliquely forwards and out¬ 
wards. The internal cuneiform has likewise 
an internal ligament, which proceeds from its 
internal part directly backwards to the navi¬ 
cular; it lies above the tendon of the tibialis 
posticus. As to the plantar ligaments, that 
of the internal cuneiform is the strongest : it 
is extended between the tubercle on the na¬ 
vicular bone and that on the cuneiform, and 
is in part confounded with the tendon of the 
tibialis posticus, which sends a process out¬ 
wards to the other cuneiform bones, and 
strengthens the ligamentous fibres which belong 
to them. 
The cuneiform bones are articulated to each 
other by means of the lateral facets, which 
are lined by synovial membrane prolonged 
from that of the cuneo-scaphoid articulation. 
Each joint is strengthened by a dorsal, a 
plantar, and an interosseous ligament. The two 
1= former are extended transversely from one 
cuneiform bone to the other, the dorsal being 
considerably the stronger. The principal bond 
of union, however, is by the interosseous liga¬ 
ment, which is extended between the non- 
articular parts of the lateral surfaces of each 
. cuneiform bone. 
The cuboid bone is articulated with the 
external cuneiform ( cuboido-cuneen articula¬ 
tion ) in a manner so similar to that by which 
the cuneiform bones are articulated with each 
t other as to render a separate description super¬ 
fluous. Its synovial membrane is continuous 
with that of the cuneo-scaphoid, and its liga¬ 
ments are precisely similar to those of the 
cuneiform articulations. 
The cuboid bone is united to the scaphoid 
by means of ligaments. The outer extremity 
of the latter bone is in contact with a small 
portion of the inner surface of the former, near 
its posterior superior angle, and sometimes a 
small articular facet indicates the point of each 
bone where contact is established. The liga¬ 
ments which pass between these bones under 
all circumstances are a dorsal ligament, directed 
obliquely from without inwards, a plantar 
ligament, transverse and very thick, and an in¬ 
terosseous ligament extended between the cor¬ 
responding surfaces of the two bones, excepting 
where the facets are found, when they exist. 
Articulation of the two rows of tarsal bones 
to each other.—This is effected by means of the 
astragalus and os calcis behind, and the scaphoid 
and cuboid in front. 
Astragalo-scaphoid articulation.—The head 
of the astragalus is received into a cavity which 
is in greatest part formed by the glenoid cavity 
of the scaphoid bone, and is completed infe- 
riorly and internally by a ligament (the inferior 
calcaneo-scaphoid), which extends from the 
sustentaculum of the os calcis to the inner part 
of the inferior surface of the scaphoid. On 
the outer side and inferiorly the head of the 
astragalus is supported by a short ligament 
(the external calcaneo-scaphoid) which is at¬ 
tached posteriorly to the inner part of the os 
calcis, and in front to the external extremity of 
the scaphoid. The extension of the recipient 
cavity for the head of the astragalus by means 
of the ligaments just named was rendered 
necessary by the considerable excess in the size 
of the head of the astragalus over the glenoid 
cavity of the scaphoid. By means of these 
ligaments, too, the os calcis is connected with 
the scaphoid, although there is no articulation 
between them. 
The astragalo-scaphoid articulation is strength¬ 
ened by but one proper ligament, and that is 
situated in the dorsal aspect; it is the superior 
astragalo-scaphoid ligament, and is attached 
posteriorly to the neck of the astragalus, and in 
front to the margin of the glenoid cavity ; the 
transverse extent of this ligament is equal to 
that of the scaphoid bone on its dorsal surface ; 
the direction of its fibres is forwards and out¬ 
wards. It is a thin fibrous expansion, covered 
superiorly by the extensor brevis digitorum 
muscle, and on its inferior surface lined by the 
synovial membrane of the joint. 
Calcaneo-cuboid articulation.—The articular 
surface on the os calcis is slightly concave in 
the direction from above downwards ; that on 
the cuboid is convex in the same direction. 
The two surfaces are closely adapted to each 
other, and their union maintained by the fol¬ 
lowing ligaments :—1. The superior or dorsal 
calcaneo-cuboid ligament, which consists of but 
a few fibres extending from the superior and 
anterior part of the os calcis to the cuboid. 
2. The internal calcaneo-cuboid ligament, a 
short, strong, quadrilateral ligament from three 
to four lines in breadth, placed in great part