.gif)
Hip (anatomy)
Encyclopedia
In vertebrate
anatomy
, hip (or "coxa" in medical terminology) refer to either an anatomical region or a joint.
The hip region is located lateral
to the gluteal region (i.e. the buttock), inferior to the iliac crest
, and overlying the greater trochanter
of the femur
, or "thigh bone". In adults, three of the bones of the pelvis have fused into the hip bone
which forms part of the hip region.
The hip joint, scientifically referred to as the acetabulofemoral joint (art. coxae), is the joint
between the femur and acetabulum
of the pelvis
and its primary function is to support the weight of the body in both static (e.g. standing) and dynamic (e.g. walking or running) postures. The hip joints are the most important part in retaining balance. The pelvic inclination angle, which is the single most important element of human body posture, is adjusted at the hips.
, and the ischial tuberosity
("sitting bone").
The hip joint is a synovial joint
formed by the articulation of the rounded head of the femur
and the cup-like acetabulum
of the pelvis. It forms the primary connection between the bones of the lower limb and the axial skeleton
of the trunk and pelvis. Both joint surfaces are covered with a strong but lubricated layer called articular hyaline cartilage
.
The cuplike acetabulum forms at the union of three pelvic bones the ilium
, pubis
, and ischium. The Y-shaped growth plate that separates them, the triradiate cartilage, is fused definitively at ages 14–16. It is a special type of spheroidal or ball and socket joint
where the roughly spherical femoral head is largely contained within the acetabulum and has an average radius of curvature of 2.5 cm. The acetabulum grasps almost half the femoral ball, a grip augmented by a ring-shaped fibrocartilaginous lip, the acetabular labrum
, which extends the joint beyond the equator.
The head of the femur is attached to the shaft by a thin neck region that is often prone to fracture in the elderly, which is mainly due to the degenerative effects of osteoporosis
.
The acetabulum is oriented inferiorly, laterally and anteriorly, while the femoral neck is directed superiorly, medially, and anteriorly.
An abnormally small angle is known as coxa vara
and an abnormally large angle as coxa valga
. Because changes in shape of the femur naturally affects the knee, coxa valga is often combined with genu varum (bow-leggedness), while coxa vara leads to genu valgum
(knock-knees).
Changes in CCD angle is the result of changes in the stress patterns applied to the hip joint. Such changes, caused for example by a dislocation, changes the trabecula
r patterns inside the bones. Two continuous trabecular systems emerging on auricular surface of the sacroiliac joint
meander and criss-cross each other down through the hip bone, the femoral head, neck, and shaft.
On the lateral side of the hip joint the fascia lata
is strengthened to form the iliotibial tract
which functions as a tension band and reduces the bending loads on the proximal part of the femur.
The capsule attaches to the hip bone outside the acetabular lip which thus projects into the capsular space. On the femoral side, the distance between the head's cartilaginous rim and the capsular attachment at the base of the neck is constant, which leaves a wider extracapsular part of the neck at the back than at the front.
The strong but loose fibrous capsule of the hip joint permits the hip joint to have the second largest range of movement (second only to the shoulder
) and yet support the weight of the body, arms and head.
The capsule has two sets of fibers: longitudinal and circular.
The extracapsular ligaments are the iliofemoral
, ischiofemoral
, and pubofemoral ligament
s attached to the bones of the pelvis (the ilium
, ischium, and pubis
respectively). All three strengthen the capsule and prevent an excessive range of movement in the joint. Of these, the Y-shaped and twisted iliofemoral ligament is the strongest ligament in the human body.
In the upright position, it prevents the trunk from falling backward without the need for muscular activity. In the sitting position, it becomes relaxed, thus permitting the pelvis to tilt backward into its sitting position. The iliofemoral ligament prevents excessive adduction and internal rotation of the hip. The ischiofemoral ligament prevents medial (internal) rotation while the pubofemoral ligament restricts abduction and internal rotation of the hip joint.
The zona orbicularis
, which lies like a collar around the most narrow part of the femoral neck
, is covered by the other ligaments which partly radiate into it. The zona orbicularis acts like a buttonhole on the femoral head and assists in maintaining the contact in the joint.
The intracapsular ligament, the ligamentum teres
, is attached to a depression in the acetabulum (the acetabular notch) and a depression on the femoral head (the fovea of the head). It is only stretched when the hip is dislocated, and may then prevent further displacement.
It is not that important as a ligament but can often be vitally important as a conduit of a small artery to the head of the femur. This arterial branch is not present in everyone but can become the only blood supply to the bone in the head of the femur when the neck of the femur is fractured or disrupted by injury in childhood.
(profunda femoris), but there are numerous variations and one or both may also arise directly from the femoral artery
. There is also a small contribution from a small artery in the ligament of the head of the femur which is a branch of the posterior division of the obturator artery, which becomes important to avoid avascular necrosis
of the head of the femur
when the blood supply from the medial and lateral circumflex arteries are disrupted (e.g. through fracture of the neck of the femur along their course).
The hip has two anatomically important anastomoses
, the cruciate
and the trochanteric anastomoses
, the latter of which provides most of the blood to the head of the femur. These anastomoses exist between the femoral artery or profunda femoris and the gluteal vessels.
, resulting in three degrees of freedom and three pair of principal directions: Flexion
and extension
around a transverse axis (left-right); lateral rotation and medial rotation around a longitudinal axis (along the thigh); and abduction
and adduction
around a sagittal axis (forward-backward); and a combination of these movements (i.e. circumduction, a compound movement in which the leg describes the surface of an irregular cone).
It should be noted that some of the hip muscles also act on either the vertebral joints or the knee joint, that with their extensive areas of origin and/or insertion, different part of individual muscles participate in very different movements, and that the range of movement varies with the position of the hip joint.
Additionally, the inferior
and superior gemelli
may be termed triceps coxae together with the obturator internus
, and their function simply is to assist the latter muscle.
The movements of the hip joint is thus performed by a series of muscles which are here presented in order of importance with the range of motion from the neutral zero-degree position indicated:
. The femora
are also more widely spaced in females, so as to widen the opening in the hip bone and thus facilitate childbirth. Finally, the ilium and its muscle attachment are shaped so as to situate the buttocks away from the birth canal, where contraction of the buttocks could otherwise damage the baby.
The female hips have long been associated with both fertility
and general expression of sexuality
. Since broad hips facilitate child birth
and also serve as an anatomical cue of sexual maturity, they have been seen as an attractive trait for women for thousands of years. Many of the classical poses women take when sculpted, painted or photographed, such as the Odalisque
, serve to emphasize the prominence of their hips. Similarly, women's fashion
through the ages has often drawn attention to the girth of the wearer's hips.
Vertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...
anatomy
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
, hip (or "coxa" in medical terminology) refer to either an anatomical region or a joint.
The hip region is located lateral
Lateral
Lateral may refer to:*Lateral , an anatomical direction*Lateral canal, a canal built beside another stream*Lateral consonant, an ℓ-like consonant in which air flows along the sides of the tongue...
to the gluteal region (i.e. the buttock), inferior to the iliac crest
Iliac crest
-External links: - "Superficial muscles of the gluteal region and posterior thigh." - "Anterior Abdominal Wall: Osteology and Surface Anatomy " - "The Back, Posterior View" * *...
, and overlying the greater trochanter
Greater trochanter
The greater trochanter of the femur is a large, irregular, quadrilateral eminence and a part of the skeletal system.It is directed a little lateralward and backward, and, in the adult, is about 1 cm lower than the head...
of the femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
, or "thigh bone". In adults, three of the bones of the pelvis have fused into the hip bone
Hip bone
The hip bone, innominate bone or coxal bone is a large, flattened, irregularly shaped bone, constricted in the center and expanded above and below...
which forms part of the hip region.
The hip joint, scientifically referred to as the acetabulofemoral joint (art. coxae), is the joint
Joint
A joint is the location at which two or more bones make contact. They are constructed to allow movement and provide mechanical support, and are classified structurally and functionally.-Classification:...
between the femur and acetabulum
Acetabulum
The acetabulum is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.-Structure:...
of the pelvis
Pelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
and its primary function is to support the weight of the body in both static (e.g. standing) and dynamic (e.g. walking or running) postures. The hip joints are the most important part in retaining balance. The pelvic inclination angle, which is the single most important element of human body posture, is adjusted at the hips.
Region
The five or so tubercles and the lower lateral borders of the sacrumSacrum
In vertebrate anatomy the sacrum is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx...
, and the ischial tuberosity
Tuberosity of the ischium
-External links: - "The Female Perineum: Bones" - "Major Joints of the Lower Extremity: Hip bone "...
("sitting bone").
- Proximally the femur is largely covered by muscles and, as a consequence, the greater trochanterGreater trochanterThe greater trochanter of the femur is a large, irregular, quadrilateral eminence and a part of the skeletal system.It is directed a little lateralward and backward, and, in the adult, is about 1 cm lower than the head...
is often the only palpable bony structure. Distally on the femur some more palpable bony structures are the condyles.
Articulation
Synovial joint
A Synovial joint, also known as a diarthrosis, is the most common and most movable type of joint in the body of a mammal. As with most other joints, synovial joints achieve movement at the point of contact of the articulating bones....
formed by the articulation of the rounded head of the femur
Femur head
The femur head is the highest part of the thigh bone . It is supported by the neck of the femur.The head is globular and forms rather more than a hemisphere, is directed upward, medialward, and a little forward, the greater part of its convexity being above and in front.Its surface is smooth,...
and the cup-like acetabulum
Acetabulum
The acetabulum is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.-Structure:...
of the pelvis. It forms the primary connection between the bones of the lower limb and the axial skeleton
Axial skeleton
The axial skeleton consists of the 80 bones along the central axis of the human body. It is composed of six parts; the human skull, the ossicles of the middle ear, the hyoid bone of the throat, the rib cage, sternum and the vertebral column...
of the trunk and pelvis. Both joint surfaces are covered with a strong but lubricated layer called articular hyaline cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...
.
The cuplike acetabulum forms at the union of three pelvic bones the ilium
Ilium (bone)
The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...
, pubis
Pubis (bone)
In vertebrates, the pubic bone is the ventral and anterior of the three principal bones composing either half of the pelvis.It is covered by a layer of fat, which is covered by the mons pubis....
, and ischium. The Y-shaped growth plate that separates them, the triradiate cartilage, is fused definitively at ages 14–16. It is a special type of spheroidal or ball and socket joint
Ball and socket joint
A ball and socket joint is a joint in which the distal bone is capable of motion around an indefinite number of axes, which have one common center...
where the roughly spherical femoral head is largely contained within the acetabulum and has an average radius of curvature of 2.5 cm. The acetabulum grasps almost half the femoral ball, a grip augmented by a ring-shaped fibrocartilaginous lip, the acetabular labrum
Acetabular labrum
The acetabular labrum is a ring of cartilage that surrounds the acetabulum ....
, which extends the joint beyond the equator.
The head of the femur is attached to the shaft by a thin neck region that is often prone to fracture in the elderly, which is mainly due to the degenerative effects of osteoporosis
Osteoporosis
Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis the bone mineral density is reduced, bone microarchitecture is deteriorating, and the amount and variety of proteins in bone is altered...
.
The acetabulum is oriented inferiorly, laterally and anteriorly, while the femoral neck is directed superiorly, medially, and anteriorly.
Articular angles
- The transverse angle of the acetabular inlet (also called Sharp's angle and is generally the angle referred to by acetabular angle without further specification) can be determined by measuring the angle between a line passing from the superior to the inferior acetabular rim and the horizontal plane; an angle which normally measures 51° at birth and 40° in adults, and which affects the acetabular lateral coverage of the femoral head and several other parameters.
- The sagittal angle of the acetabular inlet is an angle between a line passing from the anterior to the posterior acetabular rim and the sagittal plane. It measures 7° at birth and increases to 17° in adults.
- Wiberg's centre-edge angle (CE angle) is an angle between a vertical line and a line from the centre of the femoral head to the most lateral part of the acetabulum, as seen on an anteroposterior radiograph.
- The vertical-centre-anterior margin angle (VCA) is an angle formed from a vertical line (V) and a line from the centre of the femoral head (C) and the anterior (A) edge of the dense shadow of the subchondral bone slightly posterior to the anterior edge of the acetabulum, with the radiograph being taken from the false angle, that is, a lateral view rotated 25 degrees towards becoming frontal.
- The articular cartilage angle (AC angle, also called Hilgenreiner angle) is an angle formed parallel to the weight bearing dome, that is, the sourcil, and the horizontal plane, or a line connecting the corner of the triangular cartilage and the lateral acetabular rim.
Femoral neck angle
The angle between the longitudinal axes of the femoral neck and shaft, called the caput-collum-diaphyseal angle or CCD angle, normally measures approximately 150° in newborn and 126° in adults (coxa norma).An abnormally small angle is known as coxa vara
Coxa vara
Coxa vara is a deformity of the hip, whereby the angle between the ball and the shaft of the femur is reduced to less than 120 degrees. This results in the leg being shortened, and therefore a limp occurs. It is commonly caused by injury, such as a fracture...
and an abnormally large angle as coxa valga
Coxa valga
It is a deformity of the hip where the angle formed between the head and neck of the femur and its shaft is increased, usually above 135 degrees. It is caused by a slipped epiphysis of the femoral head.-See also:*Coxa vara*Genu valgum*Genu varum...
. Because changes in shape of the femur naturally affects the knee, coxa valga is often combined with genu varum (bow-leggedness), while coxa vara leads to genu valgum
Genu valgum
Genu valgum, commonly called "knock-knee", is a condition where the knees angle in and touch one another when the legs are straightened. Women have a wider pelvis than men and a relatively shorter length of the thigh bone, and as a result, have a greater static genu valgum than men...
(knock-knees).
Changes in CCD angle is the result of changes in the stress patterns applied to the hip joint. Such changes, caused for example by a dislocation, changes the trabecula
Trabecula
A trabecula is a small, often microscopic, tissue element in the form of a small beam, strut or rod, generally having a mechanical function, and usually composed of dense collagenous tissue They can be composed of other materials; in the heart, for example, muscles such as trabeculae carneae...
r patterns inside the bones. Two continuous trabecular systems emerging on auricular surface of the sacroiliac joint
Sacroiliac joint
The sacroiliac joint or SI joint is the joint in the bony pelvis between the sacrum and the ilium of the pelvis, which are joined together by strong ligaments. In humans, the sacrum supports the spine and is supported in turn by an ilium on each side...
meander and criss-cross each other down through the hip bone, the femoral head, neck, and shaft.
- In the hip bone, one system arises on the upper part of auricular surface to converge onto the posterior surface of the greater sciatic notchGreater sciatic notchAbove the ischial spine is a large notch, the greater sciatic notch, converted into a foramen by the sacrospinous ligament.It transmits the Piriformis, the superior and inferior gluteal vessels and nerves, the sciatic and posterior femoral cutaneous nerves, the internal pudendal vessels, and the...
, from where its trabeculae are reflected to the inferior part of the acetabulum. The other system emerges on the lower part of the auricular surface, converges at the level of the superior gluteal line, and is reflected laterally onto the upper part of the acetabulum. - In the femur, the first system lines up with a system arising from the lateral part of the femoral shaft to stretch to the inferior portion of the femoral neck and head. The other system lines up with a system in the femur stretching from the medial part of the femoral shaft to the superior part of the femoral head.
On the lateral side of the hip joint the fascia lata
Fascia lata
-Thickness:It is an investment for the whole of the thigh, but varies in thickness in different parts.Thus, it is thicker in the upper and lateral part of the thigh, where it receives a fibrous expansion from the Glutæus maximus, and where the Tensor fasciæ latæ is inserted between its layers; it...
is strengthened to form the iliotibial tract
Iliotibial tract
The iliotibial tract or iliotibial band is a longitudinal fibrous reinforcement of the fascia lata. It is attached to the anterolateral iliac tubercle portion of the external lip of the iliac crest and to the lateral condyle of the tibia...
which functions as a tension band and reduces the bending loads on the proximal part of the femur.
Capsule
- Main article: Capsule of hip jointCapsule of hip jointThe articular capsule is strong and dense.Above, it is attached to the margin of the acetabulum 5 to 6 mm. beyond the labrum behind; but in front, it is attached to the outer margin of the labrum, and, opposite to the notch where the margin of the cavity is deficient, it is connected to the...
The capsule attaches to the hip bone outside the acetabular lip which thus projects into the capsular space. On the femoral side, the distance between the head's cartilaginous rim and the capsular attachment at the base of the neck is constant, which leaves a wider extracapsular part of the neck at the back than at the front.
The strong but loose fibrous capsule of the hip joint permits the hip joint to have the second largest range of movement (second only to the shoulder
Shoulder
The human shoulder is made up of three bones: the clavicle , the scapula , and the humerus as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder make up the shoulder joints. The major joint of the shoulder is the glenohumeral joint, which...
) and yet support the weight of the body, arms and head.
The capsule has two sets of fibers: longitudinal and circular.
- The circular fibers form a collar around the femoral neck called the zona orbicularisZona orbicularisThe zona orbicularis or annular ligament is a ligament on the neck of the femur formed by the circular fibers of the articular capsule of the hip joint...
. - The longitudinal retinacular fibers travel along the neck and carry blood vessels.
Ligaments
The hip joint is reinforced by five ligaments, of which four are extracapsular and one intracapsular.The extracapsular ligaments are the iliofemoral
Iliofemoral ligament
The iliofemoral ligament is a ligament of the hip joint which extends from the ilium to the femur in front of the joint. It is also referred to as the Y-ligament or the ligament of Bigelow, and any combinations of these names....
, ischiofemoral
Ischiofemoral ligament
The ischiocapsular ligament consists of a triangular band of strong fibers on the posterior side of the hip joint...
, and pubofemoral ligament
Pubofemoral ligament
The pubofemoral ligament is a ligament on the inferior side of the hip joint.This ligament is attached, above, to the obturator crest and the superior ramus of the pubis; below, it blends with the capsule and with the deep surface of the vertical band of the iliofemoral ligament....
s attached to the bones of the pelvis (the ilium
Ilium (bone)
The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...
, ischium, and pubis
Pubis (bone)
In vertebrates, the pubic bone is the ventral and anterior of the three principal bones composing either half of the pelvis.It is covered by a layer of fat, which is covered by the mons pubis....
respectively). All three strengthen the capsule and prevent an excessive range of movement in the joint. Of these, the Y-shaped and twisted iliofemoral ligament is the strongest ligament in the human body.
In the upright position, it prevents the trunk from falling backward without the need for muscular activity. In the sitting position, it becomes relaxed, thus permitting the pelvis to tilt backward into its sitting position. The iliofemoral ligament prevents excessive adduction and internal rotation of the hip. The ischiofemoral ligament prevents medial (internal) rotation while the pubofemoral ligament restricts abduction and internal rotation of the hip joint.
The zona orbicularis
Zona orbicularis
The zona orbicularis or annular ligament is a ligament on the neck of the femur formed by the circular fibers of the articular capsule of the hip joint...
, which lies like a collar around the most narrow part of the femoral neck
Femur neck
The femur neck or neck of the femur is a flattened pyramidal process of bone, connecting the femoral head with the femoral shaft, and forming with the latter a wide angle opening medialward.- Angle of inclination :...
, is covered by the other ligaments which partly radiate into it. The zona orbicularis acts like a buttonhole on the femoral head and assists in maintaining the contact in the joint.
The intracapsular ligament, the ligamentum teres
Ligament of head of femur
The ligament of the head of the femur , or the round ligament of the femur , is a triangular, somewhat flattened band implanted by its apex into the antero-superior part of the fovea capitis femoris; its base is attached by two bands, one into either side of the acetabular notch, and between these...
, is attached to a depression in the acetabulum (the acetabular notch) and a depression on the femoral head (the fovea of the head). It is only stretched when the hip is dislocated, and may then prevent further displacement.
It is not that important as a ligament but can often be vitally important as a conduit of a small artery to the head of the femur. This arterial branch is not present in everyone but can become the only blood supply to the bone in the head of the femur when the neck of the femur is fractured or disrupted by injury in childhood.
Blood supply
The hip joint is supplied with blood from the medial circumflex femoral and lateral circumflex femoral arteries, which are both usually branches of the deep artery of the thighProfunda femoris artery
The profunda femoris artery is a branch of the femoral artery that, as its name suggests, travels more deeply than the rest of the femoral artery.-Structure:...
(profunda femoris), but there are numerous variations and one or both may also arise directly from the femoral artery
Femoral artery
The femoral artery is a general term comprising a few large arteries in the thigh. They begin at the inguinal ligament and end just above the knee at adductor canal or Hunter's canal traversing the extent of the femur bone....
. There is also a small contribution from a small artery in the ligament of the head of the femur which is a branch of the posterior division of the obturator artery, which becomes important to avoid avascular necrosis
Avascular necrosis
Avascular necrosis is a disease where there is cellular death of bone components due to interruption of the blood supply. Without blood, the bone tissue dies and the bone collapses...
of the head of the femur
Femur head
The femur head is the highest part of the thigh bone . It is supported by the neck of the femur.The head is globular and forms rather more than a hemisphere, is directed upward, medialward, and a little forward, the greater part of its convexity being above and in front.Its surface is smooth,...
when the blood supply from the medial and lateral circumflex arteries are disrupted (e.g. through fracture of the neck of the femur along their course).
The hip has two anatomically important anastomoses
Anastomosis
An anastomosis is the reconnection of two streams that previously branched out, such as blood vessels or leaf veins. The term is used in medicine, biology, mycology and geology....
, the cruciate
Cruciate anastomosis
The cruciate anastomosis is an anastomosis in the upper thigh of the inferior gluteal artery, the lateral and medial circumflex femoral arteries, and the first perforating artery of the profunda femoris artery...
and the trochanteric anastomoses
Trochanteric anastomosis
The trochanteric anastomosis provides circulation around the head of the femur. It includes the superior and inferior gluteal arteries and the medial and lateral circumflex femoral arteries ....
, the latter of which provides most of the blood to the head of the femur. These anastomoses exist between the femoral artery or profunda femoris and the gluteal vessels.
Muscles and movements
The hip muscles act on three mutually perpendicular main axes, all of which pass through the center of the femoral headFemur head
The femur head is the highest part of the thigh bone . It is supported by the neck of the femur.The head is globular and forms rather more than a hemisphere, is directed upward, medialward, and a little forward, the greater part of its convexity being above and in front.Its surface is smooth,...
, resulting in three degrees of freedom and three pair of principal directions: Flexion
Flexion
In anatomy, flexion is a position that is made possible by the joint angle decreasing. The skeletal and muscular systems work together to move the joint into a "flexed" position. For example the elbow is flexed when the hand is brought closer to the shoulder...
and extension
Extension (kinesiology)
In kinesiology, extension is a movement of a joint that results in increased angle between two bones or body surfaces at a joint. Extension usually results in straightening of the bones or body surfaces involved. For example, extension is produced by extending the flexed elbow. Straightening of...
around a transverse axis (left-right); lateral rotation and medial rotation around a longitudinal axis (along the thigh); and abduction
Abduction (kinesiology)
Abduction, in functional anatomy, is a movement which draws a limb away from the median plane of the body. It is thus opposed to adduction.-Upper limb:* of arm at shoulder ** Supraspinatus** Deltoid* of hand at wrist...
and adduction
Adduction
Adduction is a movement which brings a part of the anatomy closer to the middle sagittal plane of the body. It is opposed to abduction.-Upper limb:* of arm at shoulder ** Subscapularis** Teres major** Pectoralis major** Infraspinatus...
around a sagittal axis (forward-backward); and a combination of these movements (i.e. circumduction, a compound movement in which the leg describes the surface of an irregular cone).
It should be noted that some of the hip muscles also act on either the vertebral joints or the knee joint, that with their extensive areas of origin and/or insertion, different part of individual muscles participate in very different movements, and that the range of movement varies with the position of the hip joint.
Additionally, the inferior
Inferior gemellus muscle
The inferior gemellus muscle is a muscle of the human body.The Gemelli are two small muscular fasciculi, accessories to the tendon of the Obturator internus which is received into a groove between them....
and superior gemelli
Superior gemellus muscle
The superior gemellus muscle is a muscle of the human body.The Gemelli are two small muscular fasciculi, accessories to the tendon of the Obturator internus which is received into a groove between them....
may be termed triceps coxae together with the obturator internus
Obturator internus muscle
The obturator internus muscle originates on the medial surface of the obturator membrane, the ischium near the membrane, and the rim of the pubis.It exits the pelvic cavity through the lesser sciatic foramen....
, and their function simply is to assist the latter muscle.
The movements of the hip joint is thus performed by a series of muscles which are here presented in order of importance with the range of motion from the neutral zero-degree position indicated:
- Lateral or external rotation (30° with the hip extended, 50° with the hip flexed): gluteus maximusGluteus maximus muscleThe gluteus maximus is the largest and most superficial of the three gluteal muscles...
; quadratus femorisQuadratus femoris muscleThe quadratus femoris is a flat, quadrilateral skeletal muscle. Located on the posterior side of the hip joint, it is a strong external rotator and adductor of the thigh, but also acts to stabilize the femoral head in the Acetabulum.- Course :...
; obturator internusObturator internus muscleThe obturator internus muscle originates on the medial surface of the obturator membrane, the ischium near the membrane, and the rim of the pubis.It exits the pelvic cavity through the lesser sciatic foramen....
; dorsal fibers of gluteus mediusGluteus medius muscleThe gluteus medius , one of the three gluteal muscles, is a broad, thick, radiating muscle, situated on the outer surface of the pelvis....
and minimusGluteus minimus muscleThe gluteus minimus , the smallest of the three gluteal muscles, is situated immediately beneath the gluteus medius.-Origin and insertion:...
; iliopsoasIliopsoas-External links:*...
(including psoas majorPsoas major muscle-External links: - "Posterior Abdominal Wall: Muscles of the Posterior Abdominal Wall"* *...
from the vertebral column); obturator externusObturator externus muscleThe obturator externus muscle 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 considered part of the gluteal region....
; adductor magnusAdductor magnus muscleThe 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 is called the "adductor portion", and the portion arising from the tuberosity of the ischium is called the "hamstring portion"...
, longusAdductor longus muscleIn 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 adduct the thigh and it is innervated by the obturator nerve...
, brevisAdductor brevis muscleThe adductor brevis is a muscle in the thigh situated immediately behind the pectineus and adductor longus.-Origin and insertion:It is somewhat triangular in form, and arises by a narrow origin from the outer surfaces of the superior and inferior rami of the pubis, between the gracilis and...
, and minimusAdductor minimus muscleIn human anatomy, the adductor minimus is a small and flat skeletal muscle in the thigh which constitutes the upper, lateral part of the adductor magnus muscle....
; piriformisPiriformis muscleThe piriformis is a muscle in the gluteal region of the lower limb. It was first named by Spigelius, a professor from the University of Padua in the 16th century.- Origin and insertion :...
; and sartoriusSartorius muscleThe Sartorius muscle – the longest muscle in the human body – is a long thin muscle that runs down the length of the thigh. Its upper portion forms the lateral border of the femoral triangle.-Origin and insertion:...
. The iliofemoral ligamentIliofemoral ligamentThe iliofemoral ligament is a ligament of the hip joint which extends from the ilium to the femur in front of the joint. It is also referred to as the Y-ligament or the ligament of Bigelow, and any combinations of these names....
inhibits lateral rotation and extension, this is why the hip can rotate laterally to a greater degree when it is flexed. - Medial or internal rotation (40°): anterior fibers of gluteus mediusGluteus medius muscleThe gluteus medius , one of the three gluteal muscles, is a broad, thick, radiating muscle, situated on the outer surface of the pelvis....
and minimusGluteus minimus muscleThe gluteus minimus , the smallest of the three gluteal muscles, is situated immediately beneath the gluteus medius.-Origin and insertion:...
; tensor fascia latae; the part of adductor magnusAdductor magnus muscleThe 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 is called the "adductor portion", and the portion arising from the tuberosity of the ischium is called the "hamstring portion"...
inserted into the adductor tubercleAdductor tubercleThe medial lip of the linea aspera ends below at the summit of the medial condyle, in a small tubercle, the adductor tubercle, which affords insertion to the tendon of the vertical fibers of Adductor magnus.-External links:*...
; and, with the leg abducted also the pectineusPectineus muscleThe pectineus muscle is a flat, quadrangular muscle, situated at the anterior part of the upper and medial aspect of the thigh....
. - Extension or retroversion (20°): gluteus maximusGluteus maximus muscleThe gluteus maximus is the largest and most superficial of the three gluteal muscles...
(if put out of action, active standing from a sitting position is not possible, but standing and walking on a flat surface is); dorsal fibers of gluteus mediusGluteus medius muscleThe gluteus medius , one of the three gluteal muscles, is a broad, thick, radiating muscle, situated on the outer surface of the pelvis....
and minimusGluteus minimus muscleThe gluteus minimus , the smallest of the three gluteal muscles, is situated immediately beneath the gluteus medius.-Origin and insertion:...
; adductor magnusAdductor magnus muscleThe 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 is called the "adductor portion", and the portion arising from the tuberosity of the ischium is called the "hamstring portion"...
; and piriformisPiriformis muscleThe piriformis is a muscle in the gluteal region of the lower limb. It was first named by Spigelius, a professor from the University of Padua in the 16th century.- Origin and insertion :...
. Additionally, the following thigh muscles extend the hip: semimembranosusSemimembranosus muscleThe semimembranosus is a muscle in the back of the thigh. It is the most medial of the three hamstring muscles.-Structure:The semimembranosus, so called from its membranous tendon of origin, is situated at the back and medial side of the thigh....
, semitendinosusSemitendinosus muscleThe semitendinosus is a muscle in the back of the thigh; it is one of the hamstrings.-Structure:The semitendinosus, remarkable for the great length of its tendon of insertion, is situated at the posterior and medial aspect of the thigh ....
, and long head of biceps femorisBiceps femoris muscleThe biceps femoris is a muscle of the posterior thigh. As its name implies, it has two parts, one of which forms part of the hamstrings muscle group.-Origin and insertion:It has two heads of origin;...
. Maximal extension is inhibited by the iliofemoral ligamentIliofemoral ligamentThe iliofemoral ligament is a ligament of the hip joint which extends from the ilium to the femur in front of the joint. It is also referred to as the Y-ligament or the ligament of Bigelow, and any combinations of these names....
. - Flexion or anteversion (140°): the hip flexors: iliopsoasIliopsoas-External links:*...
(with psoas major from vertebral column); tensor fascia latae, pectineusPectineus muscleThe pectineus muscle is a flat, quadrangular muscle, situated at the anterior part of the upper and medial aspect of the thigh....
, adductor longusAdductor longus muscleIn 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 adduct the thigh and it is innervated by the obturator nerve...
, adductor brevisAdductor brevis muscleThe adductor brevis is a muscle in the thigh situated immediately behind the pectineus and adductor longus.-Origin and insertion:It is somewhat triangular in form, and arises by a narrow origin from the outer surfaces of the superior and inferior rami of the pubis, between the gracilis and...
, and gracilisGracilis muscleThe gracilis is the most superficial muscle on the medial side of the thigh. It is thin and flattened, broad above, narrow and tapering below.-Origin and insertion:...
. Thigh muscles acting as hip flexors: rectus femorisRectus femoris muscleThe rectus femoris muscle is one of the four quadriceps muscles of the human body. The others are the vastus medialis, the vastus intermedius , and the vastus lateralis...
and sartoriusSartorius muscleThe Sartorius muscle – the longest muscle in the human body – is a long thin muscle that runs down the length of the thigh. Its upper portion forms the lateral border of the femoral triangle.-Origin and insertion:...
. Maximal flexion is inhibited by the thigh coming in contact with the chest. - Abduction (50° with hip extended, 80° with hip flexed): gluteus mediusGluteus medius muscleThe gluteus medius , one of the three gluteal muscles, is a broad, thick, radiating muscle, situated on the outer surface of the pelvis....
; tensor fascia latae; gluteus maximusGluteus maximus muscleThe gluteus maximus is the largest and most superficial of the three gluteal muscles...
with its attachment at the fascia lataFascia lata-Thickness:It is an investment for the whole of the thigh, but varies in thickness in different parts.Thus, it is thicker in the upper and lateral part of the thigh, where it receives a fibrous expansion from the Glutæus maximus, and where the Tensor fasciæ latæ is inserted between its layers; it...
; gluteus minimusGluteus minimus muscleThe gluteus minimus , the smallest of the three gluteal muscles, is situated immediately beneath the gluteus medius.-Origin and insertion:...
; piriformisPiriformis muscleThe piriformis is a muscle in the gluteal region of the lower limb. It was first named by Spigelius, a professor from the University of Padua in the 16th century.- Origin and insertion :...
; and obturator internusObturator internus muscleThe obturator internus muscle originates on the medial surface of the obturator membrane, the ischium near the membrane, and the rim of the pubis.It exits the pelvic cavity through the lesser sciatic foramen....
. Maximal abduction is inhibited by the neck of the femur coming into contact with the lateral pelvis. When the hips are flexed, this delays the impingement until a greater angle. - Adduction (30° with hip extended, 20° with hip flexed): adductor magnusAdductor magnus muscleThe 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 is called the "adductor portion", and the portion arising from the tuberosity of the ischium is called the "hamstring portion"...
with adductor minimusAdductor minimus muscleIn human anatomy, the adductor minimus is a small and flat skeletal muscle in the thigh which constitutes the upper, lateral part of the adductor magnus muscle....
; adductor longusAdductor longus muscleIn 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 adduct the thigh and it is innervated by the obturator nerve...
, adductor brevisAdductor brevis muscleThe adductor brevis is a muscle in the thigh situated immediately behind the pectineus and adductor longus.-Origin and insertion:It is somewhat triangular in form, and arises by a narrow origin from the outer surfaces of the superior and inferior rami of the pubis, between the gracilis and...
, gluteus maximusGluteus maximus muscleThe gluteus maximus is the largest and most superficial of the three gluteal muscles...
with its attachment at the gluteal tuberosityGluteal tuberosityThe lateral ridge of the linea aspera is very rough, and runs almost vertically upward to the base of the greater trochanter. It is termed the gluteal tuberosity, and gives attachment to part of the Glutæus maximus: its upper part is often elongated into a roughened crest, on which a more or less...
; gracilisGracilis muscleThe gracilis is the most superficial muscle on the medial side of the thigh. It is thin and flattened, broad above, narrow and tapering below.-Origin and insertion:...
(extends to the tibia); pectineusPectineus muscleThe pectineus muscle is a flat, quadrangular muscle, situated at the anterior part of the upper and medial aspect of the thigh....
, quadratus femorisQuadratus femoris muscleThe quadratus femoris is a flat, quadrilateral skeletal muscle. Located on the posterior side of the hip joint, it is a strong external rotator and adductor of the thigh, but also acts to stabilize the femoral head in the Acetabulum.- Course :...
; and obturator externusObturator externus muscleThe obturator externus muscle 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 considered part of the gluteal region....
. Of the thigh muscles, semitendinosusSemitendinosus muscleThe semitendinosus is a muscle in the back of the thigh; it is one of the hamstrings.-Structure:The semitendinosus, remarkable for the great length of its tendon of insertion, is situated at the posterior and medial aspect of the thigh ....
is especially involved in hip adduction. Maximal adduction is impeded by the thighs coming into contact with one another. This can be avoided by abducting the opposite leg, or having the legs alternately flexed/extended at the hip so they travel in different planes and do not intersect.
Sexual dimorphism and cultural significance
In humans, unlike other animals, the hip bones are substantially different in the two sexes. The hips of human females widen during pubertyPuberty
Puberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...
. The femora
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
are also more widely spaced in females, so as to widen the opening in the hip bone and thus facilitate childbirth. Finally, the ilium and its muscle attachment are shaped so as to situate the buttocks away from the birth canal, where contraction of the buttocks could otherwise damage the baby.
The female hips have long been associated with both fertility
Fertility
Fertility is the natural capability of producing offsprings. As a measure, "fertility rate" is the number of children born per couple, person or population. Fertility differs from fecundity, which is defined as the potential for reproduction...
and general expression of sexuality
Human sexuality
Human sexuality is the awareness of gender differences, and the capacity to have erotic experiences and responses. Human sexuality can also be described as the way someone is sexually attracted to another person whether it is to opposite sexes , to the same sex , to either sexes , or not being...
. Since broad hips facilitate child birth
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...
and also serve as an anatomical cue of sexual maturity, they have been seen as an attractive trait for women for thousands of years. Many of the classical poses women take when sculpted, painted or photographed, such as the Odalisque
Odalisque
An odalisque was a female slave in an Ottoman seraglio. She was an assistant or apprentice to the concubines and wives, and she might rise in status to become one of them...
, serve to emphasize the prominence of their hips. Similarly, women's fashion
Fashion
Fashion, a general term for a currently popular style or practice, especially in clothing, foot wear, or accessories. Fashion references to anything that is the current trend in look and dress up of a person...
through the ages has often drawn attention to the girth of the wearer's hips.
See also
- Belly danceBelly danceBelly dance or Bellydance is a "Western"-coined name for a traditional "Middle Eastern" dance, especially raqs sharqi . It is sometimes also called Middle Eastern dance or Arabic dance in the West, or by the Greco-Turkish term çiftetelli...
r - Body shapeBody shapeHuman body shape is a complex phenomenon with sophisticated detail and function. The general shape or figure of a person is defined mainly by skeletal structure, muscles and fat...
- Femoral Acetabular ImpingementFemoral Acetabular ImpingementFemoroacetabular Impingement or hip impingement syndrome is a condition affecting the hip joint in young and middle-aged adults. Impingement occurs when the ball shaped femoral head rubs abnormally or doesn't have full range of motion in the acetabular socket...
- Haunch
- Hip dysplasia (human)Hip dysplasia (human)Hip dysplasia, developmental dysplasia of the hip or congenital dysplasia of the hip is a congenital or acquired deformation or misalignment of the hip joint.-Terminology:...
- Hip examinationHip examinationIn medicine, physiotherapy, and chiropractic, the hip examination, or hip exam, is undertaken when a patient has a complaint of hip pain and/or signs and/or symptoms suggestive of hip joint pathology...
- Hip replacementHip replacementHip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. Hip replacement surgery can be performed as a total replacement or a hemi replacement. Such joint replacement orthopaedic surgery generally is conducted to relieve arthritis pain or fix severe...
- Obstetrical DilemmaObstetrical DilemmaThe Obstetrical Dilemma refers to the evolutionary development of the human species through a number of biological changes, specifically the shifting of the females' pelvic bones, thereby shortening the fetal incubation period....
- Sexual dimorphismSexual dimorphismSexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
- Snapping hip syndromeSnapping hip syndromeSnapping hip syndrome is a medical condition characterized by a snapping sensation felt when the hip is flexed and extended. This may be accompanied by an audible snapping or popping noise and pain or discomfort. Pain often decreases with rest and diminished activity...
- Waist-hip ratio