The quadratus femoris is a flat, quadrilateral

skeletal muscle Skeletal muscle (commonly referred to as muscle) is one of the three types of vertebrate muscle tissue, the others being cardiac muscle and smooth muscle. They are part of the somatic nervous system, voluntary muscular system and typically are a ...

. Located on the posterior side of the

hip joint In vertebrate anatomy, the hip, or coxaLatin ''coxa'' was used by Celsus in the sense "hip", but by Pliny the Elder in the sense "hip bone" (Diab, p 77) (: ''coxae'') in medical terminology, refers to either an anatomical region or a joint o ...

, it is a strong external rotator and adductor of the thigh, but also acts to stabilize the

femoral head The femoral head (femur head or head of the femur) is the highest part of the thigh bone (femur The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the ...

in the

acetabulum The acetabulum (; : acetabula), also called the cotyloid cavity, is a wikt:concave, concave surface of the pelvis. The femur head, head of the femur meets with the pelvis at the acetabulum, forming the Hip#Articulation, hip joint. Structure The ...

. The quadratus femoris is used in Meyer's muscle pedicle grafting to prevent avascular necrosis of femur head.

Course

It originates on the lateral border of the

ischial tuberosity The ischial tuberosity (or tuberosity of the ischium, tuber ischiadicum), also known colloquially as the sit bones or sitz bones, or as a pair the sitting bones, is a large posterior bony protuberance on the superior ramus of the ischium. It ...

of the

ischium The ischium (; : is ...

of the

pelvis The pelvis (: pelves or pelvises) is the lower part of an Anatomy, anatomical Trunk (anatomy), trunk, between the human abdomen, abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also c ...

. From there, it passes laterally to its insertion on the posterior side of the head of the femur: the quadrate tubercle on the

intertrochanteric crest The intertrochanteric crest is a prominent bony ridge upon the posterior surface of the femur at the junction of the neck and the shaft of the femur. It extends between the greater trochanter superiorly, and the lesser trochanter inferiorly. An ...

and along the quadrate line, the vertical line which runs downward to bisect the

lesser trochanter In human anatomy, the lesser trochanter is a conical, posteromedial, bony projection from the shaft of the femur. It serves as the principal insertion site of the iliopsoas muscle. Structure The lesser trochanter is a conical posteromedial p ...

on the medial side of the femur. Along its course, quadratus is aligned edge to edge with the

inferior gemellus The gemelli muscles are the inferior gemellus muscle and the superior gemellus muscle, two small accessory fasciculi to the tendon of the internal obturator muscle. The gemelli muscles belong to the lateral rotator group of six muscles of the hip ...

above and the

adductor magnus The adductor magnus is a large triangular muscle, situated on the medial side of the thigh. It consists of two parts. The portion which arises from the ischiopubic ramus (a small part of the inferior ramus of the pubis, and the inferior ramu ...

below, so that its upper and lower borders run horizontal and parallel. At its origin, the upper margin of the

is separated from it by the terminal branches of the

medial femoral circumflex The medial circumflex femoral artery (internal circumflex artery, medial femoral circumflex artery) is an artery in the upper thigh that arises from the profunda femoris artery''.'' It supplies arterial blood to several muscles in the region, as w ...

vessels. A

bursa Bursa () is a city in northwestern Turkey and the administrative center of Bursa Province. The fourth-most populous city in Turkey and second-most populous in the Marmara Region, Bursa is one of the industrial centers of the country. Most of ...

is often found between the front of this muscle and the

Clinical significance

Groin pain can be a disabling ailment with many potential root causes: one such cause, often overlooked, is quadratus femoris

tendinitis Tendinopathy is a type of tendon disorder that results in pain, swelling, and impaired function. The pain is typically worse with movement. It most commonly occurs around the shoulder ( rotator cuff tendinitis, biceps tendinitis), elbow ( tenn ...

Magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and ...

can show abnormal signal intensity at the insertion of the right quadratus femoris tendon, which suggests inflammation of the area. Since the muscle works to laterally rotate and adduct the femur, actions involving the lower body can strain the muscle. In addition, patients present with hip pain and an increased signal intensity of the MRI of the quadratus femoris have been shown to also have a significantly narrower ischiofemoral space compared to the general populace. The ischiofemoral impingement may be a cause of the hip pain associated with quadratus femoris tendinitis.

Additional images

File:Gray245.png, Right femur. Posterior surface. File:Gray344.png, Structures surrounding right hip-joint. File:Gray832.png, Nerves of the right lower extremity Posterior view. File:Slide6hh.JPG, Quadratus femoris muscle File:Slide1BIBI.JPG, Muscles of Thigh. Anterior views.

Notes

References

* * (ISBN for the Americas 1-58890-159-9.) *

External links

PTCentral
* {{Authority control Hip muscles Hip lateral rotators Deep lateral rotators of the hip Muscles of the lower limb