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Fragments of the article: Cracraft J. The functional morphology of the hind limb of the domestic pigeon, Columba livia. (1971). The author studied the ligamentum capitis femoris (LCF) in the pigeon. Its strength is noted and its attachment areas and biomechanics are described. The LCF functions in conjunction with the posterior acetabular ligament. Translation into Russian is available at the link: 1971CracraftJ.
Quote, p. 182
TERES LIGAMENT
The teres ligament (ter lig; fig. 2) arises from the
dorsal portion of the head of the femur (fovea capitis; see Stolpe, 1932, p.165). A short and broad ligament, it curves ventromedially to the anteroventral
edge of the inner opening of the acetabulum.
POSTERIOR ACETABULAR LIGAMENT
Posterior to the teres ligament is a broad
ligamentous-like connective tissue band, which is named here the posterior
acetabular ligament. It attaches anteriorly to the teres ligament and to the
posterior portion of the fovea capitis. Its pelvic attachment is to the
posterior rim of the inner opening of the acetabulum. The remaining portion of
the inner opening of the acetabulum is covered by a thin membrane, which serves
as the medial limit of the joint cavity. The dorsal portion is more fibrous
than the ventral.
ARTICULAR SURFACE OF THE ACETABULUM:
Anterior and posterior to the attachment of the teres
ligament, the articular cartilage is present only on the dorsal part of the
acetabulum (fig. 1); the ratio of chondrocytes to fibrous connective tissue
becomes progressively smaller in a ventral direction.
Quote, pp. 183-184
In the area of the teres ligament the articular surface
of the ventral part of the acetabulum has been replaced completely by the
ligament (fig. 2). Dorsally, the articular cartilage of the pelvis is composed
of greater amounts of collagenous tissue.
Quote, p. 184
In the area of the teres ligament the structure of the
articular surface does not change except that it is reduced in extent dorsally.
TEREs
LIGAMENT: This is a large, strong ligament composed almost wholly of
collagenous tissue. The ventral edge, near its origin from the fovea capitis,
is slightly cartilaginous. The fact that the teres ligament inserts onto the
ventral rim of the acetabulum is clearly evident in cross sections (fig. 2).
Dorsally, a long, thin fibrous strand of tissue arises from the acetabulum,
passes medially and then laterally, and attaches to the dorsal edge of the
ligament; this strand represents the membrane covering the inner opening of the
acetabulum (fig. 2). The membrane is clearly differentiated into two zones: (1)
a lateral (facing the joint cavity), deeply staining layer of cuboidal cells,
and (2) a medial (facing the abdominal cavity), wider, collagenous layer. The
lateral thin zone represents the synovial membrane.
Quote, pp. 184-186
All the structures are apparently organized so as to
set a limit to the amount of protraction.With retraction, the joint structures
become loose and only regain their tautness when the femur is retracted far
beyond the position that could possibly be attained under any natural conditions.
As the femur approaches the fully protracted position, four parts of the joint
begin to tighten and limit further anterior movement: (a) the obturator ridge
moves posteroventrally and thus the joint capsule on the posterior side of the
joint becomes taut, (b) the proximo-anterior surface of the shaft moves posterodorsally
and the anteroventral part of the capsule (including the "ligamentum
ilio-sacrale") becomes taut, (c) the shaft is moving anteriorly and so the
ventral part of the capsule becomes taut, and (d) the fovea capitis moves
laterally away from the inside opening of the acetabulum, causing the teres and
posterior acetabular ligament to tighten. All of these features function simultaneously
to set a limit to the amount of protraction. With retraction, the preceding structures
change position with the following results: (a) the obturator ridge moves
anterodorsally and the posterior part of the capsule becomes loose, (b) the
proximo-anterior surface of the shaft moves anteroventrally and the antero-ventral
part of the capsule becomes loose, (c) the shaft moves posteriorly and the
ventral part of the capsule loosens, and (d) the fovea capitis moves medially
toward the inside opening of the acetabulum, thus slackening the teres and posterior
acetabular ligament.
ABDUCTION-ADDUCTION
When the femur is fully protracted, no abduction is possible because of the trochanter-antitrochanter articulation and the ventral part of the capsule, and no adduction is possible because of the teres and posterior acetabular ligaments and the posterior part of the capsule (in some specimens a slight adduction was possible).
Cracraft J. The functional morphology of the hind limb of the domestic pigeon, Columba livia. Bull Am Mus Nat Hist. New York,1971;144(3)171-268. digitallibrary.amnh.org , digitallibrary.amnh.org/pdf
The work is cited in the following publications: LCF страуса, LCF нанду, LCF казуара, LCF эму.
Joel Cracraft. Research Fellow, Department of
Ornithology. The American Museum of Natural History. Assistant Professor of
Anatomy, Department of Anatomy, University of Illinois.
ligamentum capitis femoris, ligamentum teres, ligament of head of femur, anatomy, mechanical properties, birds, animals, synonym, biomechanics, attachment
NB! Fair practice / use: copied for the purposes of criticism, review, comment, research and private study in accordance with Copyright Laws of the US: 17 U.S.C. §107; Copyright Law of the EU: Dir. 2001/29/EC, art.5/3a,d; Copyright Law of the RU: ГК РФ ст.1274/1.1-2,7
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