In human anatomy, the ligament of the head of the femur (round ligament of the femur, ligamentum teres femoris, the foveal ligament, or Fillmore’s ligament) is a
ligament
A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the:
* Peritoneal ...
located in the
hip
In vertebrate anatomy, hip (or "coxa"Latin ''coxa'' was used by Celsus in the sense "hip", but by Pliny the Elder in the sense "hip bone" (Diab, p 77) in medical terminology) refers to either an anatomical region or a joint.
The hip region is ...
. It is triangular in shape and somewhat flattened. The ligament is implanted by its apex into the
antero- superior part of the
fovea capitis femoris and its base is attached by two bands, one into either side of the
acetabular notch
The acetabular notch is a deep notch in the acetabulum of the hip bone. The acetabular notch is continuous with a circular non-articular depression, the acetabular fossa, at the bottom of the cavity: this depression is perforated by numerous apert ...
, and between these bony attachments it blends with the
transverse ligament.
['']Gray's Anatomy
''Gray's Anatomy'' is a reference book of human anatomy written by Henry Gray, illustrated by Henry Vandyke Carter, and first published in London in 1858. It has gone through multiple revised editions and the current edition, the 42nd (Octo ...
'' (1918), see infobox
It is ensheathed by the
synovial membrane
The synovial membrane (also known as the synovial stratum, synovium or stratum synoviale) is a specialized connective tissue that lines the inner surface of capsules of synovial joints and tendon sheath. It makes direct contact with the fibro ...
, and varies greatly in strength in different subjects; occasionally only the
synovial fold exists, and in rare cases even this is absent.
The ligament of the head of the femur contains within it the acetabular branch of the
obturator artery
The obturator artery is a branch of the internal iliac artery that passes antero-inferiorly (forwards and downwards) on the lateral wall of the pelvis, to the upper part of the obturator foramen, and, escaping from the pelvic cavity through the o ...
.
Function
The ligament is made tense when the
thigh
In human anatomy, the thigh is the area between the hip (pelvis) and the knee. Anatomically, it is part of the lower limb.
The single bone in the thigh is called the femur. This bone is very thick and strong (due to the high proportion of bone ...
is semiflexed and the limb then adducted or rotated outward; it is, on the other hand, relaxed when the limb is abducted.
Research suggests it contributes little influence as a
ligament
A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the:
* Peritoneal ...
past childhood, although it may still be important in transmitting arterial supply to the femoral head.
In humans, it has been suggested that it is not the ligamentum teres but the hip capsule (specifically the iliofemoral, ischiofemoral and pubofemoral ligaments) that provides the primary resistance to dislocation in the extended hip. However, recent research has suggested the ligamentum teres of the femur may have a number of functions, including a significant biomechanical role on the basis of cadaveric studies where increases of range of motion were seen after sectioning of the ligament.
Other animals
It has been suggested that some animals, such as the orangutan and Indian elephant, lack a ligamentum teres. However, the presence of a ligamentum teres, albeit with a morphology different from the human version, has been found upon dissection in both these animals. In the orangutan, it is believed to play a significant role in preventing dislocation of the femoral head within extreme ranges of motion. In the Indian elephant, it is the primary support of the hip joint when the hind limbs are abducted.
References
{{DEFAULTSORT:Ligament Of Head Of Femur
Ligaments of the lower limb