300 THE ARTICULATIONS OR JOINTS. 
A distinct synovial membrane lines all parts of the capsule of the joint. 
Articulatio Calcaneo-cuboidea.—This is situated between the anterior concavo- 
convex surface of the os calcis and the posterior similar surface of the cuboid. 
The ligaments which invest this joint constitute a calcaneo-cuboid capsule, whose 
parts are arranged in relation to the four non-articular sides of the cuboid bone, 
and are especially strong upon the 
plantar aspect, in relation to their great 
Tease importance in resisting strains. 
metatarsal ligament The internal calcaneo-cuboid ligament 
(Fig. 229) occupies part of the interval 
between the astragalus and os calcis— 
sinus tarsi. It is sometimes called the 
interosseous calcaneo-cuboid ligament, 
and, in conjunction with the superior or 
external caleaneo-scaphoid lgament, it 
forms a V-shaped structure, of which 
its Plantar intercuneiform ligaments 
Plantar inter- = the single end is attached to the os 
ligaments calcis, and the double ends separate to 
reach contiguous areas on the scaphoid 
Plantar aise. and cuboid respectively. 
ligaments The dorsal calcaneo-cuboid ligament 
a eee (Fig. 229) is a broad portion of the 
cuboid ligament capsule extending between the dorsal 
one ip lentes surfaces of the two bones. 
Biaytar Galeanes: The external calcaneo-cuboid ligament 
euboid ligament (Fig, 229) is another but narrower part 
of the capsule which extends from the 
outer aspect of the os calcis to the outer 
side of the cuboid, immediately behind 
the facet on the tuberosity. 
The inferior calcaneo-cuboid ligaments 
are two in number—a superficial and a 
deep. The superficial series of fibres, 
the long plantar ligament (Fig. 2350), is 
attached to the under surface of the os 
calcis in front of its tuberosities. It forms 
a long powerful structure which runs forwards to be fixed to the under surface of the 
cuboid ridge, but many of its fibres pass superficial to the tendon of the peroneus 
longus, and extend to the bases of the third, fourth, and fifth metatarsal bones. 
The deep series of fibres, the short plantar ligament (Fig. 230),is distinctly separated 
from the former by a layer of areolar tissue. It forms a broad but short band of great 
strength, which is attached to the under surface of the front end of the os calecis, 
and extends to the under surface of the cuboid just behind the ridge. Both of 
these ligaments are of great importance in maintaining the longitudinal arch of the 
foot, and in this respect are only second to the inferior calcaneo-scaphoid ligaments. 
A synovial membrane lines the capsule. 
Transverse Tarsal Articulation.—This is a term sometimes applied to the 
astragalo-scaphoid and calcaneo-cuboid joints. These articulations donotcommunicate 
with each other; and although there is an occasional direct articulation between the 
scaphoid and cuboid, it does not constitute an extension of the transverse tarsal joint, but 
is a prolongation from the series of scapho-cuneiform and euneo-cuboid articulations. 
Nevertheless there is always a set of ligaments which bind the scaphoid and 
cuboid bones together, and these may be regarded as accessory to the various 
transverse tarsal joints. 
The dorsal scapho-cuboid ligament (Fig. 229) consists of short oblique fibres which 
attach the contiguous dorsal surfaces of the cuboid and scaphoid bones. 
The plantar scapho-cuboid ligament (Fig. 230) is transverse in direction, and 
extends between adjacent plantar areas of the cuboid and scaphoid bones. 
The interosseous scapho-cuboid ligament intervenes between contiguous surfaces 
cuneiforn 
Inferior cale 
scaphoid ligaments 
Fic. 230.—LIGAMENTS ON PLANTAR ASPECT OF FOOT. 
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