In human anatomy, the quadrate ligament or ligament of Denucé is one of the ligaments of the

proximal radioulnar joint The proximal radioulnar articulation, also known as the proximal radioulnar joint (PRUJ), is a synovial pivot joint between the circumference of the head of the radius and the ring formed by the radial notch of the ulna and the annular ligament ...

in the upper

forearm The forearm is the region of the upper limb between the elbow and the wrist. The term forearm is used in anatomy to distinguish it from the arm, a word which is most often used to describe the entire appendage of the upper limb, but which in ...

Structure

The quadrate ligament is a fibrous band attached to the inferior border of the

radial notch The radial notch of the ulna (lesser sigmoid cavity) is a narrow, oblong, articular depression on the lateral side of the coronoid process; it receives the circumferential articular surface of the head of the radius. It is concave from before bac ...

on the

ulna The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of t ...

and to the neck of the

radius In classical geometry, a radius ( : radii) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', meaning ray but also the ...

. Its borders are strengthened by fibers from the upper border of the annular ligament. The ligament is long, wide, and thick.

Function

The quadrate ligament reinforces the inferior part of the capsule of the elbow joint and contributes to joint stability by securing the proximal radius against the radial notch and by restricting excessive

supination Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relativ ...

(10–20° restriction) and, to a lesser degree,

pronation Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relativ ...

(5–8°).

History

The quadrate ligament was first described by the French anatomist Jean-Paul-Louis Denucé in 1854, but its function and even presence has been disputed in anatomical literature ever since. It received little attention before Nomina Anatomica Parisiensia recognized it as a functional structure in 1955. , nevertheless, found no evidence of the ligament, and described it as "nothing more than a thin fibrous layer" of the joint capsule — somewhat in line with Denucé's note that the ligament could be considered a simple extension of the synovial recess or an extension of the annular ligament. , on the other hand, described the ligament as having an anterior border denser and stronger than the posterior, with a thin central portion. This description was, however, not corroborated by who, while recognizing the ligament's importance, found it to be of even thickness.

Notes

References

* * * * * {{Authority control Ligaments of the upper limb