The hip bone is a large irregular bone, constricted in the center and expanded above and below. In some vertebrates it is composed of three parts: the ilium and the pubis; the two hip bones join at the pubic symphysis and together with the sacrum and coccyx comprise the skeletal component of the pelvis – the pelvic girdle which surrounds the pelvic cavity. They are connected to the sacrum, part of the axial skeleton, at the sacroiliac joint; each hip bone is connected to the corresponding femur through the large ball and socket joint of the hip. The hip bone is formed by three parts: ilium and pubis. At birth, these three components are separated by hyaline cartilage, they join each other in a Y-shaped portion of cartilage in the acetabulum. By the end of puberty the three regions will have fused together, by the age 25 they will have ossified; the two hip bones join each other at the pubic symphysis. Together with the sacrum and coccyx, the hip bones form the pelvis. Ilium is the largest region.
It makes up two fifths of the acetabulum. It is divisible into the ala or wing of ilium; the body of ilium forms the sacroiliac joint with the sacrum. The edge of the wing of ilium forms the S-shaped iliac crest, located through the skin; the iliac crest shows clear marks of the attachment of the three abdominal wall muscles. The ischium forms the lower and back part of the hip bone and is located below the ilium and behind the pubis; the ischium is the strongest of the three regions. It is divisible into three portions: the body, the superior ramus, the inferior ramus; the body forms one-third of the acetabulum. The ischium forms a large swelling, the tuberosity of the ischium referred to colloquially as the "sit bone"; when sitting, the weight is placed upon the ischial tuberosity. The gluteus maximus leaves it free in the seated position; the pubic region or pubis is the anterior of the three parts forming the hip bone. It is divisible into a body, a superior ramus, an inferior ramus; the body forms one-fifth of the acetabulum.
The body forms the wide, strong and flat portion of the pubic bone which unites with the other pubic bone in the pubic symphysis. The fibrocartilaginous pad which lies between the symphysial surfaces of the coxal bones, that secures the pubic symphysis, is called the interpubic disc; the pelvic brim is a continuous oval ridge of bone that runs along the pubic symphysis, pubic crests, arcuate lines, sacral alae, sacral promontory. The false pelvis is that portion superior to the pelvic brim; the true pelvis is the region inferior to the pelvic brim, entirely surrounded by bone. The pelvic inlet is the opening delineated by the pelvic brim; the widest dimension of the pelvic inlet is from left to right, that is, along the frontal plane. The pelvic outlet is the margin of the true pelvis, it is bounded anteriorly by the pubic arch, laterally by the ischia, posteriorly by the sacrum and coccyx. The superior pubic ramus is a part of the pubic bone, it extends from the body to the median plane where it articulates with its fellow of the opposite side.
It is conveniently described in two portions: a medial flattened part and a narrow lateral prismoid portion. The inferior pubic ramus is flat, it passes downward from the medial end of the superior ramus. It becomes narrower as it descends and joins with the inferior ramus of the ischium below the obturator foramen; the hip bone is ossified from eight centers: three primary, one each for the ilium and pubis, five secondary, one each for the iliac crest, the anterior inferior spine, the tuberosity of the ischium, the pubic symphysis, one or more for the Y-shaped piece at the bottom of the acetabulum. The centers appear in the following order: in the lower part of the ilium above the greater sciatic notch, about the eighth or ninth week of fetal life. At birth, the three primary centers are quite separate, the crest, the bottom of the acetabulum, the ischial tuberosity, the inferior rami of the ischium and pubis being still cartilaginous. By the seventh or eighth year, the inferior rami of the pubis and ischium are completely united by bone.
About the thirteenth or fourteenth year, the three primary centers have extended their growth into the bottom of the acetabulum, are there separated from each other by a Y-shaped portion of cartilage, which now presents traces of ossification by two or more centers. One of these, the os acetabuli, appears about the age of twelve, between the ilium and pubis, fuses with them about the age of eighteen; the ilium and ischium become joined, lastly the pubis and ischium, through the intervention of this Y-shaped portion. At about the age of puberty, ossification takes place in each of the remaining portions, they join with the rest of the bone between the twentieth and twenty-f
The sacrotuberous ligament is situated at the lower and back part of the pelvis. It is flat, triangular in form, it runs from the sacrum to the tuberosity of the ischium. It is a remnant of part of Biceps femoris muscle; the sacrotuberous ligament is attached by its broad base to the posterior superior iliac spine, the posterior sacroiliac ligaments, to the lower transverse sacral tubercles and the lateral margins of the lower sacrum and upper coccyx. Its oblique fibres descend laterally, converging to form a thick, narrow band that widens again below and is attached to the medial margin of the ischial tuberosity, it spreads along the ischial ramus as the falciform process, whose concave edge blends with the fascial sheath of the internal pudendal vessels and pudendal nerve. The lowest fibres of gluteus maximus are attached to the posterior surface of the ligament; the ligament is pierced by the coccygeal branches of the inferior gluteal artery, the perforating cutaneous nerve and filaments of the coccygeal plexus.
The membranous falciform process of the sacrotuberous ligament was found to be absent in 13% of cadavers. When present it extends towards the ischioanal fossa travelling along the ischial ramus and fusing with the obturator fascia; the lower border of the ligament was found to be directly continuous with the tendon of origin of the long head of the Biceps femoris in 50% of subjects. Biceps femoris could therefore act to stabilise the sacroiliac joint via the sacrotuberous ligament; the sacrotuberous ligament contains the coccygeal branch of the inferior gluteal artery. If the pudendal nerve becomes entrapped between this ligament and the sacrospinous ligament causing perineal pain, the sacrotuberous ligament is surgically severed to relieve the pain; this article incorporates text in the public domain from page 309 of the 20th edition of Gray's Anatomy Anatomy figure: 13:03-04 at Human Anatomy Online, SUNY Downstate Medical Center – "Deep muscles of the gluteal region with gluteus medius and maximus muscles removed."
Anatomy figure: 17:02-05 at Human Anatomy Online, SUNY Downstate Medical Center – "Posterior view of the bones and ligaments of the hip joint." Anatomy photo:41:os-0114 at the SUNY Downstate Medical Center – "The Female Perineum" Anatomy photo:42:12-0102 at the SUNY Downstate Medical Center – "The Male Perineum and the Penis: Boundaries of the Ischioanal fossa" Anatomy image:9075 at the SUNY Downstate Medical Center hip/hip%20ligaments/ligaments7 at the Dartmouth Medical School's Department of Anatomy
From the posterior border of the body of the Ischium there extends backward a thin and pointed triangular eminence, the ischial spine, more or less elongated in different subjects. It can serve as a landmark in pudendal anesthesia; this article incorporates text in the public domain from page 235 of the 20th edition of Gray's Anatomy Anatomy photo:41:os-0105 at the SUNY Downstate Medical Center - "The Female Perineum: Osteology" Anatomy photo:44:st-0724 at the SUNY Downstate Medical Center - "The Male Pelvis"
Anatomical terms of bone
Many anatomical terms descriptive of bone are defined in anatomical terminology, are derived from Greek and Latin. A long bone is one, cylindrical in shape, being longer than it is wide. However, the term describes the shape of a bone, not its size, relative. Long bones are found in the legs, as well as in the fingers and toes. Long bones function as levers, they are responsible for the body's height. A short bone is one, cube-like in shape, being equal in length and thickness; the only short bones in the human skeleton are in the carpals of the wrists and the tarsals of the ankles. Short bones provide support as well as some limited motion; the term “flat bone” is something of a misnomer because, although a flat bone is thin, it is often curved. Examples include the cranial bones, the scapulae, the sternum, the ribs. Flat bones serve as points of attachment for muscles and protect internal organs. Flat bones do not have a medullary cavity. An irregular bone is one that does not have an classified shape and defies description.
These bones tend to have more complex shapes, like the vertebrae that support the spinal cord and protect it from compressive forces. Many facial bones the ones containing sinuses, are classified as irregular bones. A sesamoid bone is a round bone that, as the name suggests, is shaped like a sesame seed; these bones form in tendons. The sesamoid bones protect tendons by helping them overcome compressive forces. Sesamoid bones vary in number and placement from person to person but are found in tendons associated with the feet and knees; the only type of sesamoid bone, common to everybody is the kneecap, the largest of the sesamoid bones. A condyle is the round prominence at the end of a bone, most part of a joint – an articulation with another bone; the epicondyle refers to a projection near a condyle the medial epicondyle of the humerus. These terms derive from Greek. An eminence refers to a small projection or bump of bone, such as the medial eminence. A process refers to a large projection or prominent bump, as does a promontory such as the sacral promontory.
Both tubercle and tuberosity refer to a projection or bump with a roughened surface, with a "tubercle" smaller than a "tuberosity". These terms are derived from Tuber. A ramus refers to an extension of bone, such as the ramus of the mandible in the jaw or Superior pubic ramus. Ramus may be used to refer to nerves, such as the ramus communicans. A facet refers to a flattened articular surface. A line refers to a long, thin projection with a rough surface. Ridge and crest refer to a narrow line. Unlike many words used to describe anatomical terms, the word ridge is derived from Old English. A spine, as well as referring to the spinal cord, may be used to describe a long, thin projection or bump; these terms are used to describe bony protuberances in specific parts of the body. The Malleolus is the bony prominence on each side of the ankle; these are known as the lateral malleolus. Each leg is supported by two bones, the tibia on the inner side of the leg and the fibula on the outer side of the leg; the medial malleolus is the prominence on the inner side of the ankle, formed by the lower end of the tibia.
The lateral malleolus is the prominence on the outer side of the ankle, formed by the lower end of the fibula. The trochanters are parts of the femur, it may refer to the greater, lesser, or third trochanter The following terms are used to describe cavities that connect to other areas: A foramen is any opening referring to those in bone. Foramina inside the body of humans and other animals allow muscles, arteries, veins, or other structures to connect one part of the body with another. A canal is a long, tunnel-like foramen a passage for notable nerves or blood vessels; the following terms are used to describe cavities that do not connect to other areas: A fossa is a depression or hollow in a bone, such as the hypophyseal fossa, the depression in the sphenoid bone. A meatus is a short canal. A fovea is a small pit on the head of a bone. An example of a fovea is the fovea capitis of the head of the femur; the following terms are used to describe the walls of a cavity: A labyrinth refers to the bony labyrinth and membranous labyrinth, components of the inner ear, due to their fine and complex structure.
A sinus refers to a bony cavity within the skull. A joint, or articulation is the region where adjacent bones contact each other, for example the elbow, shoulder, or costovertebral joint. Terms that refer to joints include: articular process, referring to a projection that contacts an adjacent bone. Suture, referring to an articulation between cranial bones. Bones are described with the terms head, shaft and base The head of a bone refers to the proximal end of the bone; the shaft refers to the elongated sections of long bone, the neck the segment between the head and shaft. The end of the long bone opposite to the head is known as the base; the cortex of a bone is used to refer to its outer layers, medulla used to
In human anatomy, a hamstring is one of the three posterior thigh muscles in between the hip and the knee. The hamstrings are quite susceptible to injury. In quadrupeds, the hamstring is the single large tendon found behind comparable area; the common criteria of any hamstring muscles are: Muscles should originate from ischial tuberosity. Muscles should be inserted in the tibia or in the fibula. Muscles will be innervated by the tibial branch of the sciatic nerve. Muscle will participate in flexion of the knee extension of the hip joint; those muscle which fulfill all of the four criteria are called true hamstrings. The adductor magnus reaches only up to the adductor tubercle of the femur, but it is included amongst the hamstrings because the tibial collateral ligament of the knee joint morphologically is the degenerated tendon of this muscle; the ligament is attached to two millimeters from the adductor tubercle. The three muscles of the posterior thigh flex the knee, while all but the short head of biceps femoris extend the hip.
The three'true' hamstrings cross both the hip and the knee joint and are therefore involved in knee flexion and hip extension. The short head of the biceps femoris crosses only one joint and is therefore not involved in hip extension. With its divergent origin and innervation it is sometimes excluded from the'hamstring' characterization. A portion of the adductor magnus is sometimes considered a part of the hamstrings; the hamstrings cross and act upon two joints - the hip and the knee, as such are termed biarticular muscles. Semitendinosus and semimembranosus extend the hip; the long head of the biceps femoris extends the hip, as. The hamstrings play a crucial role in many daily activities such as walking, running and controlling some movement in the trunk. In walking, they are most important as an antagonist to the quadriceps in the deceleration of knee extension. Imaging the hamstring muscles is performed with an ultrasound and/or MRI; the biceps femoris is most injured, followed by semitendinosus.
Semimembranosus injury is rare. Imaging is useful in differentiating the grade of strain if the muscle is torn. In this setting, the level and degree of retraction can be determined, serving as a useful roadmap prior to any surgery; those with a hamstring strain of greater than 60mm in length have a greater risk of recurrence. The distal semitendinosus tendon is one of the tendons that can be used in the surgical procedure ACL reconstruction. In this procedure, a piece of it is used to replace the anterior cruciate ligament; the ACL is one of the four major ligaments in the knee. The word "ham" is derived from the Old English ham or hom meaning the hollow or bend of the knee, from a Germanic base where it meant "crooked", it gained the meaning of the leg of an animal around the 15th century. String refers to tendons, thus, the hamstrings are the string-like tendons felt on either side of the back of the knee. Hamstringing Hamstring curl Lombard's Paradox Popliteal fossa Pulled hamstring MRI Images demonstrating avulsion fracture of the hamstring muscle origin
The gluteus maximus is the main extensor muscle of the hip. It is the largest and most superficial of the three gluteal muscles and makes up a large portion of the shape and appearance of each side of the hips, its thick fleshy mass, in a quadrilateral shape, forms the prominence of the buttocks. Its large size is one of the most characteristic features of the muscular system in humans, connected as it is with the power of maintaining the trunk in the erect posture. Other primates can not sustain standing erectly; the muscle is remarkably coarse in function and structure, being made up of muscle fascicles lying parallel with one another, collected together into larger bundles separated by fibrous septa. It arises from the posterior gluteal line of the inner upper ilium, a pelvic bone, the portion of the bone including the crest of the ilium above and behind it; the fibers are lateralward. Three bursae are found in relation with the deep surface of this muscle: One of these, of large size, separates it from the greater trochanter.
When the gluteus maximus takes its fixed point from the pelvis, it extends the acetabulofemoral joint and brings the bent thigh into a line with the body. Taking its fixed point from below, it acts upon the pelvis, supporting it and the trunk upon the head of the femur, its most powerful action is to cause the body to regain the erect position after stooping, by drawing the pelvis backward, being assisted in this action by the biceps femoris, semitendinosus and adductor magnus. The gluteus maximus is a tensor of the fascia lata, by its connection with the iliotibial band steadies the femur on the articular surfaces of the tibia during standing, when the extensor muscles are relaxed; the lower part of the muscle acts as an adductor and external rotator of the limb. The upper fibers act as abductors of the hip joints; the gluteus maximus is involved from running to weight-lifting. A number of exercises focus on the gluteus maximus as well as other muscles of the upper leg. Hip thrusts Glute bridge Quadruped hip extensions Kettlebell swings Squats and variations like split squats, pistol squats and wide-stance lunges Deadlift Reverse hyperextension Four-way hip extensions Glute-ham raise Functional assessment can be useful in assessing injuries to the gluteus maximus and surrounding muscles.
These tests include: 30 Second Chair to Stand testThis test measures a participant's ability to stand up from a seated position as many times as possible in a thirty-second period of time. Testing the number of times a person can stand up in a thirty-second period helps assess strength, flexibility and endurance, which can help determine how far along a person is in rehabilitation, or how much work is still to be done. Passive piriformis stretch; the piriformis test measures flexibility of the gluteus maximus. This requires a trained professional and is based on the angle of external and internal rotation in relation to normal range of motion without injury or impingement. In other primates, gluteus maximus consists of ischiofemoralis, a small muscle that corresponds to the human gluteus maximus and originates from the ilium and the sacroiliac ligament, gluteus maximus proprius, a large muscle that extends from the ischial tuberosity to a more distant insertion on the femur. In adapting to bipedal gait, reorganization of the attachment of the muscle as well as the moment arm was required.
Table of muscles of the human body Coccyx This article incorporates text in the public domain from page 474 of the 20th edition of Gray's Anatomy Anatomy photo:13:st-0403 at the SUNY Downstate Medical Center Cross section image: pelvis/pelvis-female-17—Plastination Laboratory at the Medical University of Vienna Cross section image: pelvis/pelvis-e12-15—Plastination Laboratory at the Medical University of Vienna Cross section image: pembody/body18b—Plastination Laboratory at the Medical University of Vienna Muscles/GluteusMaximus at exrx.net
The obturator foramen is the large opening created by the ischium and pubis bones of the pelvis through which nerves and blood vessels pass. It is bounded by a thin, uneven margin, to which a strong membrane is attached, presents, superiorly, a deep groove, the obturator groove, which runs from the pelvis obliquely medialward and downward; this groove is converted into the obturator canal by a ligamentous band, a specialized part of the obturator membrane, attached to two tubercles: one, the posterior obturator tubercle, on the medial border of the ischium, just in front of the acetabular notch the other, the anterior obturator tubercle, on the obturator crest of the superior ramus of the pubis Reflecting the overall sex differences between male and female pelvises, the obturator foramina are oval in the male and wider and more triangular in the female. Additionally, unilateral pelvis hypoplasia can cause differences in size between the obturator foramina, there are rare reports of individual pelvises featuring a double obturator foramen in one of the hip bones.
Through the canal the obturator artery, obturator vein and obturator nerve pass out of the pelvis. Obturator internus muscle Obturator externus muscle This article incorporates text in the public domain from page 237 of the 20th edition of Gray's Anatomy Anatomy photo:17:st-0205 at the SUNY Downstate Medical Center - "Major Joints of the Lower Extremity: hip and sacrum" Atlas image: male_urethrogram at the University of Michigan Health System - "Pelvis & Perineum: Male Urethrogram" Photo at vc.cc.tx.us