The pectineus muscle (, from the Latin word ''pecten'', meaning comb) is a flat, quadrangular
muscle
Skeletal muscles (commonly referred to as muscles) are organs
An organ is a group of tissues with similar functions. Plant life and animal life rely on many organs that co-exist in organ systems.
A given organ's tissues can be broadly cat ...

, situated at the
anterior
Standard anatomical terms of location deal unambiguously with the anatomy
Anatomy (Greek ''anatomē'', 'dissection') is the branch of biology concerned with the study of the structure of organism
In biology, an organism (from Ancient ...
(front) part of the upper and
medial
Medial may refer to:
Mathematics
* Medial magma, a mathematical identity in algebra Geometry
* Medial axis, in geometry the set of all points having more than one closest point on an object's boundary
* Medial graph, another graph that repres ...
(inner) aspect of the
thigh
In Outline of human anatomy, human anatomy, the thigh is the area between the hip (pelvis) and the knee. Anatomically, it is part of the Human leg, lower limb.
The single bone in the thigh is called the femur. This bone is very thick and strong ...

. The pectineus muscle is the most anterior
adductor of the hip. The muscle does
adduct
An adduct (from the Latin ''adductus'', "drawn toward" alternatively, a contraction of "addition product") is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all comp ...
and internally rotate the thigh but its primary function is
hip flexion
A flexor is a muscle that flexes a joint
A joint or articulation (or articular surface) is the connection made between bones in the body which link the skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw-Hi ...
.
It can be classified in the
medial compartment of thigh
The medial compartment of thigh is one of the fascial compartments of the thigh and contains the hip adductor muscles and the gracilis muscle
The gracilis muscle (; Latin for "slender") is the most superficial muscle on the medial side of the ...
(when the function is emphasized) or the
anterior compartment of thigh
The anterior compartment of thigh contains muscles which extend the knee and flex the hip.
Structure
The anterior compartment is one of the fascial compartments of the thigh that contains groups of muscles together with their nerves and blood supp ...
(when the nerve is emphasized).
Structure
The pectineus muscle arises from the
pectineal line of the
pubis and to a slight extent from the surface of bone in front of it, between the
iliopectineal eminence
Medial to the anterior inferior iliac spine is a broad, shallow groove, over which the Iliacus muscle, iliacus and Psoas major muscle, psoas major muscles pass. This groove is bounded medially by an eminence, the iliopubic eminence (or iliopectineal ...
and
pubic tubercle
The pubic tubercle is a prominent tubercle on the Pubis (bone), superior ramus of the Pubis (bone), pubis bone of the pelvis.
Structure
The pubic tubercle is a prominent forward-projecting tubercle on the upper border of the medial portion of ...
, and from the fascia covering the anterior surface of the muscle; the fibers pass downward, backward, and lateral, to be inserted into the
pectineal line of the femur which leads from the
lesser trochanter
The lesser trochanter of the femur is a conical eminence, which varies in size in different species
In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of ...
to the
linea aspera
The linea aspera ( la, rough line) is a ridge of roughened surface on the posterior surface of the shaft
Shaft may refer to:
Rotating machine elements
* Shaft (mechanical engineering), a rotating machine element used to transmit power
* Line s ...
.
Relations
The pectineus is in relation by its anterior surface with the pubic portion of the
fascia lata
The fascia lata is the deep fascia
Deep fascia (or investing fascia) is a fascia
A fascia (; plural fasciae ; adjective fascial; from Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European l ...
, which separates it from the
femoral artery
The femoral artery is a large in the and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery or and descends along the anteromedial part of the thigh in the . It enters and passes through the , ...
and
vein
Veins are blood vessels
The blood vessels are the components of the circulatory system
The circulatory system, also called the cardiovascular system or the vascular system, is an organ system
An organ system is a biological system
A b ...
and internal
, and lower down with the
profunda artery.
By its posterior surface with the
capsule of the hip joint, and with the
obturator externus
The external obturator muscle, obturator externus muscle (; OE) is a flat, triangular muscle, which covers the outer surface of the anterior wall of the pelvis.
It is sometimes considered part of the medial compartment of thigh, and sometimes co ...

and
adductor brevis
The adductor brevis is a muscle in the thigh situated immediately deep to the pectineus and adductor longus muscle, adductor longus. It belongs to the Adductor muscles of the hip, adductor muscle group. The main function of the adductor brevis ...

, 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 obtu ...
and
vein
Veins are blood vessels
The blood vessels are the components of the circulatory system
The circulatory system, also called the cardiovascular system or the vascular system, is an organ system
An organ system is a biological system
A b ...
being interposed.
By its external border with the
psoas major
The psoas major ( or ) is a long fusiform muscle located in the lateral lumbar region between the vertebral column
The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining ...

, the
femoral artery
The femoral artery is a large in the and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery or and descends along the anteromedial part of the thigh in the . It enters and passes through the , ...
resting upon the line of interval.
By its internal border with the outer edge of the
adductor longus
In the human body, the adductor longus is a skeletal muscle located in the thigh. One of the adductor muscles of the hip, its main function is to Adduction, adduct the thigh and it is innervated by the obturator nerve. It forms the medial wall o ...

.
Obturator foramen
The obturator foramen (Latin foramen obturatum) is the large opening created by the ischium and pubis (bone), pubis bones of the pelvis through which nerves and blood vessels pass.
Structure
It is bounded by a thin, uneven margin, to which a stron ...
is situated directly behind this muscle, which forms one of its coverings.
It forms part of the floor of the
femoral triangle
The femoral triangle (or Scarpa's triangle) is an anatomical region of the upper third of the thigh. It is a subfascial space which appears as a triangular depression below the inguinal ligament
In human anatomy, the inguinal region refers to eith ...
.
Innervation
The lumbar plexus is formed from the anterior rami of nerves L1 to L4 and some fibers from T12. With only five roots and two divisions, it is less complex than the brachial plexus and gives rise to a number of nerves including the femoral nerve and accessory obturator nerve. The pectineus muscle is considered a
composite muscle
Composite or hybrid muscles are those muscles which have more than one set of fibers but perform the same function and are usually supplied by different nerves for different set of fibers.
Examples
* Brachialis: Musculocutaneous nerve is motor an ...
as the innervation is by the
femoral nerve
The femoral nerve is a nerve in the thigh that supplies skin on the upper thigh and inner leg, and the muscles that extend the knee.
Structure
Femoral nerve is the major nerve supplying the anterior compartment of the thigh. It is the largest bran ...
(L2 and L3) and occasionally (20% of the population) a branch of the
obturator nerve
The obturator nerve in human anatomy arises from the ventral divisions of the second, third, and fourth lumbar nerves in the lumbar plexus; the branch from the third is the largest, while that from the second is often very small.
Structure
The obt ...
called the
accessory obturator nerve. When it is present, the accessory obturator nerve innervates a portion of the pectineus muscle, entering the muscle on its dorsomedial aspect. The greater nerve to the muscle is the femoral nerve. Unlike the obturator accessory nerve, the femoral nerve is always present and provides the sole innervation for the pectineus muscle in over 90% of cases. The muscle is also innervated by the accessory obturator nerve in the 8.7% of cases in which the nerve occurs.
[5]
Function
It is one of the muscles primarily responsible for
hip flexion
A flexor is a muscle that flexes a joint
A joint or articulation (or articular surface) is the connection made between bones in the body which link the skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw-Hi ...
. It also
adducts
An adduct (from the Latin ''adductus'', "drawn toward" alternatively, a contraction of "addition product") is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all comp ...
the thigh.
Additional images
File:Gray235.png, Right hip bone. External surface.
File:Gray344.png, Structures surrounding right hip-joint.
File:Gray430.png, Muscles of the iliac and anterior femoral regions.
File:Gray433.png, Deep muscles of the medial femoral region.
File:Gray549.png, The left femoral triangle.
File:Gray823.png, The lumbar plexus and its branches.
File:Slide3GGGGG.JPG, Pectineus muscle
File:Slide2LLLL.JPG, Pectineus muscle
File:Slide13LLLL.JPG, Pectineus muscle
File:Slide4NNNNN.JPG, Pectineus muscle
File:Slide1WWWW.JPG, Pectineus muscle
File:Slide1BOUA.JPG, Muscles of Thigh. Anterior views
File:Slide1DEEA.JPG, Muscles of Thigh. Anterior views.
See also
*
Thigh
In Outline of human anatomy, human anatomy, the thigh is the area between the hip (pelvis) and the knee. Anatomically, it is part of the Human leg, lower limb.
The single bone in the thigh is called the femur. This bone is very thick and strong ...

References
Notes
*
* Saladin, Kenneth S. Anatomy & Physiology: The Unity of Form and Function. New York, NY: McGraw-Hill, 2007. pg.493. Print.
External links
* - "Muscles of the anterior (extensor) compartment of the thigh."
* - "Deep muscles of the anterior thigh."
*
{{Authority control
Hip adductors
Hip medial rotators
Hip flexors
Thigh muscles
Medial compartment of thigh