Iliofemoral ligament

Iliofemoral
Right hip-joint from the front. (Iliofemoral ligament visible at center.)
Structures surrounding right hip-joint. (Iliofemoral ligament labeled at upper left.)
Details
From	ilium (anterior inferior iliac spine)
To	femur (intertrochanteric line)
Identifiers
Latin	ligamentum iliofemorale
TA98	A03.6.07.003
TA2	1875
FMA	42993
Anatomical terminology [edit on Wikidata]

The iliofemoral ligament is a thick and very tough triangular capsular

It is also referred to as the Y-ligament (see below). the ligament of Bigelow, the ligament of Bertin and any combinations of these names.

With a force strength exceeding 350 kg (772 lbs),^[2] the iliofemoral ligament is not only stronger than the two other ligaments of the hip joint, the ischiofemoral and the pubofemoral, but also the strongest ligament in the human body and as such is an important constraint to the hip joint.^[3]

Structure

The ligament is triangular in shape, with its apex represented by its pelvic attachment. The ligament has two though outer bands; it is thinner and weaker centrally.^[1] As the lateral portion is twisted like a screw, the two parts together take the form of an inverted Y.^{[4][verification needed]}

Arising from the

]

It is intimately connected with the

]

Function

In a standing posture, when the

As the hip flexes, the tension in the ligament is reduced and the amount of possible rotations in the hip joint is increased, which permits the pelvis to tilt backwards into its sitting angle. Lateral rotation and adduction in the hip joint is controlled by the strong transversal part, while the descending part limits medial rotation.[4]

where the rear leg is hyper-extended at the hip. Many externally rotate the rear leg while doing a front split, this external rotation when the hip is not flexed stretches the ligament even more. This "martial arts split" is distinguished by the rear knee pointing outward sideways (usually the foot along with it) rather than pointing straight down with the patella facing the floor, in a pure extension front split.

Additional images

• 
  Left hip-joint, opened by removing the floor of the acetabulum from within the pelvis.
• 
  The

  obturator externus

  .
• 
  A front split requires mobility in the ligament to adequately extend the rear hip joint.
• 
  Front oversplits require even more mobility to attain proper hip hyperextension.

References

This article incorporates text in the public domain from page 335 of the 20th edition of Gray's Anatomy (1918)

External links

• lljoints at The Anatomy Lesson by Wesley Norman (Georgetown University) (hipjointanterior)
• hip/hip%20ligaments/ligaments3 at the
  Dartmouth Medical School
  's Department of Anatomy