Hip bone Anatomy | Bone and Spine You are here: Home / Anatomy / Hip bone Anatomy Hip bone Anatomy Published - By Dr Arun Pal Singh Last Edited Apr 1, 2015 @ 5:16 pm Hip bone is also known as inominate bone or pelvic bone and is formed by fusion of three bones namely ilium, ischium and pubis bones. Hip bone forms part of pelvis and takes part in hip joint articulation. The hip bone is made up of the three parts – the ilium, pubis and ischium. Prior to puberty, the triradiate cartilage separates these constituents. At the age of 15-17, the three parts begin to fuse. Their fusion forms a cup-shaped socket known as the acetabulum, which becomes complete at 20-25 years of age. The head of the femur articulates with the acetabulum to form the hip joint. Thus the hip bone has three articulations – Sacroiliac joint – articulation with sacrum Pubic symphysis – articulation with the other hip bone . Hip joint – articulation with the head of femur.

Side determination of Hip Bone Acetabulum is on lateral side Obturator formen lies below the acetabulum, pubis being anterior and ischium posterior Flat expanded part, the ilium is above the acetabulum. Anatomical Position of Hip Bone Pubic tubercle and anterior superior iliac spine lie in same coronal plane . Pelvic surface of pubis is directed backwards and upwards Symphyseal surface of the body of pubis is in the median plane . Ilium Ilium is largest part of the hip bone and forms upper expanded plate in upper part and contributes to acetabulum formation in lower part. Roughly two fifth of acetabulum is contributed by ilium. Upper end of ilium is called iliac crest. Iliac crest is broad, convex, topmost portion of ilium which can be palpated in the flank area. Anterior end of iliac crest is called the anterior superior iliac spine which is a very important anatomical landmark. Iliac crest ends posteriorly in the posterior superior iliac spine [Located about dimple of venus about by a dimple 4 cm lateral to the second sacral spine.

] Iliac crest is divided in to a ventral segment and a dorsal segment which meet at the tubercle. The ventral segment forms more than the anterior two thirds of the crest. The dorsal segment forms less than the posterior one third of the crest. Lower end is fused with ischium and pubis at the acetabulum. Ilium has got three borders [anterior, posterior and medial ] and three surfaces [gluteal, iliac, and a sacropelvic surface]. Borders of Ilium Anterior border of ilium starts at the anterior superior iliac spine and runs downwards to the acetabulum. In upper part , the border has a notch and while its lower part has anterior inferior iliac spine. Posterior border extends from the posterior superior iliac spine to the upper end of the posterior border of the ischium. It is marked by prominence called posterior inferior iliac spine and lower a large deep notch called the greater sciatic notch. Medial Border is on the inner surface of the ilium from the iliac crest to the iliopubic eminence and separates the iliac fossa from the sacropelvic surface.

Its lower rounder part form the iliac part inlet of pelvis or arcuate line . Surfaces of Ilium Gluteal surface is the outer surface of the ilium, which is convex in front and concave behind. Three gluteal lines divide the gluteal surface. The posterior gluteal line is the shortest and extends from a point front of the posterior superior spine to a point of the posterior inferior spine. The anterior gluteal line is the longest , begins about an inch behind the anterior superior spine, runs backwards and then downwards to end at the middle of the upper border of the greater sciatic notch. The inferior gluteal line is not well defined. It begins a little above and behind the anterior inferior spine, runs backwards and downwards to end near the apex of the greater sciatic notch. Inner surface of ilium is divided by medial border into iliac fossa and sacropelvic surface. Iliac fossa is the large concave area on the inner surface of the ilium, situated in front of its medial border. It forms the lateral wall of the false pelvis. Sacropelvic surface is the uneven area on the inner surface of the ilium, behind its medial border.

It is subdivided in three parts: the iliac tuberosity, auricular surface and pelvic surface. Iliac tuberosity is a large rough area below dorsal segment of iliac crest. It is raised in the middle and depressed both above and below. Articular surface is called auricular surface and articulates with corresponding auricular surface on scarum to form sacroiliac joint. Anteroinferior to auricular surface is smooth pelvic surface which forms lateral wall of true pelvis. Preauricular surface is marked by preauricular sulcus. Attachments on Ilium Pelvis Pelvis Home > Skeletal System > Bones of the Pelvis and Lower Back > Pelvis Pelvis Located in the lower torso, the pelvis is a sturdy ring of bones that protects the delicate organs of the abdominopelvic cavity while anchoring the powerful muscles of the hip, thigh, and abdomen. Several bones unite to form the pelvis, including the sacrum, coccyx (tail bone), and the left and right coxal (hip) bones. Throughout childhood, the pelvis is made of many smaller bones that eventually fuse during adulthood to form a more rigid pelvis.

Each of the coxal bones begins as three separate bones: the ilium, ischium, and pubis.... Move up/down/left/right: Click compass arrows Rotate image: Click and drag in any direction, anywhere in the frame Identify objects: Click on them in the image 2D Interactive 3D Rotate & Zoom Change Anatomical System Change View Angle Full Pelvis Description [Continued from above] . . . The ilium is the largest, widest, and most superior of the hip bones. When you place your hands on your hips, you can feel the curved ridge of the ilium known as the iliac crest. The narrow ischium is inferior to the ilium and is the bone, along with the coccyx, that you rest your body weight on while sitting. Anterior to the ischium is the pubis, the smallest of the hip bones. The ilium, ischium, and pubis meet in the center of the hip bone to form the deep, cup-like socket of the hip joint called the acetabulum. The sacrum and coccyx also begin life as multiple bones before fusing.

Five short, wide vertebrae fuse to form the wedge-shaped sacrum, while four tiny vertebrae fuse to form the coccyx. The bones of the adult pelvis join together to form four joints: the left and right sacroiliac joints, the sacrococcygeal joint, and the pubic symphysis. The sacroiliac joints form between the sacrum and the left and right ilium to form a tight junction capable of supporting the body’s weight and resisting the force of strong muscles. Although the sacroiliac joints are synovial joints, many strong ligaments and bony ridges on the sacrum and ilium interlock to prevent movement of the bones and strengthen the joint. The cartilaginous sacrococcygeal joint unites the sacrum with the tiny coccyx and allows some slight movement of the tail bone. On the anterior side of the pelvis the pubic symphysis unites the left and right pubic bones. The pubic symphysis is a slightly flexible band of fibrocartilage that allows the independent movement of the hip bones while walking.

Women have a significantly wider and more flexible pubic symphysis compared to men, which allows the female pelvis to stretch during childbirth to accommodate the head of a fetus passing through the birth canal. Many significant structural differences, or sexual dimorphisms, exist between the male and female pelvis. Most of these differences relate to the female reproductive system and the roles of pregnancy and childbirth in the female. The bones of the male pelvis are larger, thicker, and heavier than those of the female and there is very little hollow space within the ring of the pelvic bones. The female pelvis by comparison is significantly shorter and wider, which provides a greater hollow space within for the head of a fetus to pass through during childbirth. The sacrum and coccyx curve much more but are located more posteriorly in the female pelvis to increase the space of the pelvis. Even the shape and angle of the acetabulum and hip joint differ between males and females. The female acetabulum is rotated more anteriorly than in males, resulting in differences in walking gait and posture between men and women.

Prepared by Tim Taylor, Anatomy and Physiology Instructor Pelvic Fractures-OrthoInfo - AAOS Copyright 2016 American Academy of Orthopaedic Surgeons Pelvic Fractures The pelvis is the sturdy ring of bones located at the base of the spine. Fractures of the pelvis are uncommon—accounting for only about 3% of all adult fractures. Most pelvic fractures are caused by some type of traumatic, high-energy event, such as a car collision. Because the pelvis is in proximity to major blood vessels and organs, pelvic fractures may cause extensive bleeding and other injuries that require urgent treatment. In some cases, a lower-impact event—such as a minor fall—may be enough to cause a pelvic fracture in an older person who has weaker bones. Treatment for a pelvic fracture varies depending on the severity of the injury. While lower-energy fractures can often be managed with conservative care, treatment for high-energy pelvic fractures usually involves surgery to reconstruct the pelvis and restore stability so that patients can resume their daily activities. Anatomy The pelvis is a ring of bones located at the lower end of the trunk—between the spine and the legs.

The pelvic bones include the: Sacrum (the large triangular bone at the base of the spine) Coccyx (tailbone) Hip bones Each hip bone contains three bones—the ilium, ischium, and pubis—that are separate during childhood but fuse together as we grow older. These three bones meet to form the acetabulum—the hollow cup that serves as the socket for the ball-and-socket hip joint. Bands of strong connective tissues called ligaments join the pelvis to the sacrum, creating a bowl-like cavity below the rib cage. Major nerves, blood vessels, and portions of the bowel, bladder, and reproductive organs all pass through the pelvic ring. The pelvis protects these important structures from injury. It also serves as an anchor for the muscles of the hip, thigh, and abdomen. The pelvis helps anchor the muscles and protect the organs in the lower abdomen. Top of page Description Because the pelvis is a ring-like structure, a fracture in one part of the structure is often accompanied by a fracture or damage to ligaments at another point in the structure. Doctors have identified several common pelvic fracture patterns.

The specific pattern of the fracture depends upon the direction in which it was broken and the amount of force that caused the injury. In addition to being described by the specific fracture pattern, pelvic fractures are often described as "stable" or "unstable," based on how much damage has occurred to the structural integrity of the pelvic ring. Stable fracture. In this type of fracture, there is often only one break in the pelvic ring and the broken ends of the bones line up adequately. Low-energy fractures are often stable fractures. Stable pelvic fracture patterns include: Iliac wing fracture Sacrum fracture Superior and inferior pubic ramus fracture Unstable fracture. In this type of fracture, there are usually two or more breaks in the pelvic ring and the ends of the broken bones do not line up correctly (displacement). This type of fracture is more likely to occur due to a high-energy event. Unstable pelvic fracture patterns include: Anterior-posterior compression fracture Lateral compression fracture. In this fracture, the pelvis is pushed inward. Vertical shear fracture. In this fracture, one half of the pelvis shifts upward.

Both stable and unstable pelvic fractures can also be divided into "open" fractures, in which the bone fragments stick out through the skin, or "closed" fractures, in which the skin is not broken. Open fractures are particularly serious because, once the skin is broken, infection in both the wound and the bone can occur. Immediate treatment is required to prevent infection. A pelvic fracture may result from a high-energy force, such as that generated during a: Car or motorcycle collision Crush accident Fall from a significant height (such as a ladder) Depending on the direction and magnitude of the force, these injuries can be life-threatening and require surgical treatment. Bone Insufficiency A pelvic fracture may also occur due to weak or insufficient bone. This is most common in older people whose bones have become weakened by osteoporosis. In these patients, a fracture may occur even during a fall from standing or a routine activity such as getting out of the bathtub or descending stairs. These injuries are typically stable fractures that do not damage the structural integrity of the pelvic ring, but may fracture an individual bone. Other Causes Less commonly, a fracture may occur when a piece of the ischium bone tears away from the site where the hamstring muscles attach to the bone.

This type of fracture is called an avulsion fracture and it is most common in young athletes who are still growing. An avulsion fracture does not usually make the pelvis unstable or injure internal organs. Top of page Symptoms A fractured pelvis is almost always painful. This pain is aggravated by moving the hip or attempting to walk. Often, the patient will try to keep his or her hip or knee bent in a specific position to avoid aggravating the pain. Some patients may experience swelling or bruising in the hip area. Doctor Examination Emergency Stabilization Patients with high-energy fractures will almost always go or be brought to an urgent care center or emergency room for initial treatment due to the severity of their symptoms. These patients may also have additional injuries to the head, chest, abdomen, or legs. If their injuries cause significant blood loss, it could lead to shock—a life-threatening condition that can result in organ failure. The care of patients with high-energy pelvic fractures requires a multidisciplinary approach with input from a number of medical specialists. In some cases, doctors must address airway, breathing, and circulatory problems before treating the fracture and other injuries. Physical Examination Your doctor will carefully examine your pelvis, hips, and legs.

He or she will also check for nerve injury by assessing whether you can move your ankles and toes and feel sensation on the bottom of your feet. Your doctor will also carefully examine the rest of your body to determine if you have sustained any other injuries. Imaging Studies X-rays. These studies provide images of dense structures, such as bones. All pelvic fractures require x-rays—usually from a number of different angles—to help the doctor determine how displaced place the bones are. X-ray shows an unstable pelvic fracture with disruption of the pubis (arrow) and sacroiliac joint (arrowhead). Reproduced with permission from JF Sarwark, ed: Essentials of Musculoskeletal Care, ed 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2016. Computed tomography (CT) scans. Because of the complexity of this type of injury, a CT scan is commonly ordered for pelvic fractures. A CT scan will provide a more detailed, cross-sectional image of the pelvis. Your doctor will use this information to better determine the specific pattern and extent of your injury, look for associated injuries, and aid in preoperative planning.

Magnetic resonance imaging (MRI) scans: In rare cases, your doctor may order an MRI scan to discover a fracture that cannot be seen on x-ray or CT scan. Treatment is based on a number of factors, including: The specific pattern of the fracture How much the bones are displaced Your overall condition and associated injuries Nonsurgical Treatment Your doctor may recommend nonsurgical treatment for stable fractures in which the bones are nondisplaced or minimally displaced. Nonsurgical treatments may include: Walking aids. To avoid bearing weight on your leg, your doctor may recommend that you use crutches or a walker for up to three months—or until your bones are fully healed. If you have injuries above both legs, you may need to use a wheelchair for a period of time so that you can avoid bearing weight on either leg. Medications. Your doctor may prescribe medication to relieve pain, as well as an anti-coagulant, or blood thinner, to reduce the risk of blood clots forming in the veins of your legs and pelvis. Surgical Treatment Patients with unstable pelvic fractures may require one or more surgical procedures. External fixation. Your doctor may use external fixation to stabilize your pelvic area.

In this operation, metal pins or screws are inserted into the bones through small incisions into the skin and muscle. The pins and screws project out of the skin on both sides of the pelvis where they are attached to carbon fiber bars outside the skin. The external fixator acts as a stabilizing frame to hold the broken bones in proper position. In some cases, an external fixator is used to stabilize the bones until healing is complete. In patients who are unable to tolerate a lengthy, more complicated procedure, an external fixator may be used as a temporary treatment until another procedure can be performed. In this x-ray, an external fixator has been used to stabilize the pelvis. Reproduced from Kurylo JC, Tornetta P: Initial management and classification of pelvic fractures. Instructional Course Lecture 61. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2012, pp. 3-18. Skeletal traction. Skeletal traction is a pulley system of weights and counterweights that helps realign the pieces of bone. Skeletal traction is often used immediately after an injury and removed after surgery. Occasionally, acetabular fractures can be treated with skeletal traction alone.

This is rare, however, and will be a decision made jointly with input from your doctor. During skeletal traction, metal pins are implanted in the thighbone or shinbone to help position the leg. Weights attached to the pins gently pull on the leg, keeping the broken bone fragments in as normal a position as possible. For many patients, skeletal traction also provides some pain relief. Open reduction and internal fixation. During this operation, the displaced bone fragments are first repositioned (reduced) into their normal alignment. They are then held together with screws or metal plates attached to the outer surface of the bone. In this x-ray, plates and screws have been used to repair a fractured pelvis. Reproduced from Mullis BH: Techniques of anterior pelvic fixation. Instructional Course Lecture 61. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2012, pp. 19-25. Complications There are risks associated with any surgical procedure. Before your surgery, your doctor will discuss each of these risks with you and will take specific measures to help avoid potential complications. Possible complications include: Recovery Pain Management After surgery, you will feel some pain. This is a natural part of the healing process.

Your doctor and nurses will work to reduce your pain, which can help you recover from surgery faster. Medications are often prescribed for short-term pain relief after surgery. Many types of medicines are available to help manage pain, including opioids, non-steroidal anti-inflammatory drugs (NSAIDs), and local anesthetics. Your doctor may use a combination of these medications to improve pain relief, as well as minimize the need for opioids. Be aware that although opioids help relieve pain after surgery, they are a narcotic and can be addictive. Opioid dependency and overdose has become a critical public health issue in the U.S. It is important to use opioids only as directed by your doctor. As soon as your pain begins to improve, stop taking opioids. Talk to your doctor if your pain has not begun to improve within a few days of your surgery. Early Movement In most cases, your doctor will encourage early movement. Most patients begin walking—with weight-bearing restrictions—and performing foot and leg exercises as soon as possible after surgery. Physical Therapy Specific exercises will help you regain flexibility and restore range of motion in your hip. Other exercises will help you build strength and endurance so that you are better able to perform your daily activities.

Blood Clot Prevention Although early movement is encouraged, your mobility after surgery will still be somewhat limited. For this reason, your doctor may prescribe an anticoagulant, or blood thinner, to help prevent blood clots from forming in the deep veins of your pelvis and legs. Weight Bearing Your doctor may recommend that you use crutches or a walker for a period of time. Full weight bearing is usually allowed by 3 months—or when your bones are fully healed. You may require the use of a cane or walking aid for a longer period of time. Top of page Outcomes Stable pelvic fractures tend to heal well. Unstable pelvic fractures sustained during high-energy incidents, such as car accidents, may result in significant complications, including severe bleeding, internal organ damage, and infection. If these injuries are addressed successfully, the fracture usually heals well. You may walk with a limp for several months if damage has occurred to the muscles around your pelvis. These muscles may take up to one year to become strong again. Subsequent problems, such as pain, impaired mobility, and sexual dysfunction, may result from damage to nerves and organs that is associated with the pelvic fracture.

If you found this article helpful, you may also be interested in Deep Vein Thrombosis Deep Vein Thrombosis (topic.cfm?topic=A00219). What is the Pelvic Ring? (with pictures) What is the Pelvic Ring? Last Modified Date: 17 January 2017 Copyright Protected: Top 10 unbelievable historical concurrencies The pelvic ring, also known as the pelvic girdle , is a ring of bones shaped like a basin that connects the torso to the legs. It supports the weight of the upper body and transfers some of the weight to the lower limbs when standing. It provides protection to vulnerable organs and supports posture. The primary function of the pelvic ring is to support the weight of the upper body while standing and sitting. When standing and walking, the pelvic girdle transfers the weight from the axial skeleton , which consists of the 80 bones of the head and trunk of the body, to the lower limbs. It is very strong and sturdy with limited mobility, maintaining strong bonds with the powerful muscles of the legs. The two hip bones connect and make up the pelvic ring.

It is formed where the hip bones meet at the pubic symphysis and connect with the sacrum at the sacroiliac joints. The pubic symphysis is the cartilaginous joint where the left and right pubic bone meet. The sacrum is a large triangular bone, attached to the last lumbar vertebra and the tailbone , which is wedged between the two hip bones. This is connected to the hip bones by the sacroiliac joints. The pelvic ring contains five joints. It has two sacroiliac joints, where the hip bones meet the sacrum. There are two hip joints, where the hip bones connect to the femurs, or leg bones. Lastly, there is the symphysis pubis, which connects the left and right pubic bones. Each of these joints have limited mobility, with the exception of the hip joints, as the pelvis is responsible for carrying the weight of the upper body. When weight is placed on the ring, as when sitting or standing, it transforms from a loose structure to a load-bearing stable one. This transformation is triggered when pressure travels down through the spine and causes the sacroiliac ligaments to tighten.

The pelvic ring also provides and home and protective shelter for internal organs. It protects internal reproductive organs, such as the uterus and ovaries, as well as inferior parts of the urinary tracts. These bones also protect and are attached to muscles and membranes of the external reproductive organs. Posture is also affected by the pelvis ring. These bones are held in a delicate balance that determines the curve of the spine. If the pelvic girdle is abnormally tilted, it will cause poor posture, which can lead to serious injury and discomfort. Ad seag47 Post 5 I know a lot of elderly people who have had problems with a pelvic ring injury. I guess a lot of them have some degree of osteoporosis, which makes the pelvic bones particularly vulnerable to cracking or breaking. You always hear about old people falling down and breaking their hips. What they are actually breaking are their pelvic bones. My neighbor fell and had to have plates and screws placed in his pelvic ring. The doctor said his injury had made the bones unstable, so they would have to be secured by the hardware. StarJo Post 4 @orangey03 – That sounds like a particularly bad pelvic fracture.

My little sister injured her pelvis while playing sports in junior high, but she didn't have to have surgery. The area was swollen and very sore, and her doctor told her that she would have to use crutches for three months. That should give the fracture time to heal. He told her it was important that she avoid placing weight on the pelvis during that time. He also gave her pain medication and a medicine to thin her blood. He said that because she would not be using her legs very much, she would be at risk of getting a blood clot, so the blood thinner would prevent this. lighth0se33 Post 3 I've heard that the pelvic ring will expand and loosen up when you are pregnant. I've never been pregnant, but my sister has, and she said that this made her develop a sort of waddling gait. The pelvic ring wants the baby to be able to fit through it, so it will give way to accommodate the baby. It will get looser as time progresses so that when it is time to give birth, the bones won't be in the way so much. I love how our body parts are designed to work with each other like this.

It would be awful if the pelvic ring didn't give the baby extra room to exit! ElizaBennett Post 2 You know, people tend to think of the pelvis as one hard bone, but there's more to it than that! The pubic symphysis that the article mentions? It's not bone, right? It's cartilage. So it loosens during pregnancy (that's why pregnant women waddle - I had a teacher in high school who called it "independent suspension"). And especially by the end of pregnancy, changing position can therefore cause the shape of the pelvis to change. This all becomes really important in childbirth! Some doctors seem to think we have an epidemic of babies with heads too big for their mom's pelvises, but many midwives feel that using positions like squatting that better "open up" the pelvis can get out more babies than just having women lie in bed. orangey03 Post 1 I have a friend who suffered a broken pelvis. She got into a bad car accident, and she had have surgery to repair her pelvic ring.

The doctor used what is called an “external fixator.” This is a kind of frame that sits outside the body but is attached to the pelvic bones by screws. It took her months to heal up enough to attempt walking. Even then, she had to use crutches for many more months. A broken pelvis is serious business. When you break bones in the middle of your body like that, it affects your entire body. Post your comments Hip Joint Anatomy, Hip Bones, Ligaments, Muscles 58 Shares Share 1 Tweet 1 Share 3 Email 53 The hip is the body’s second largest weight-bearing joint (after the knee ). It is a ball and socket joint at the juncture of the leg and pelvis. The rounded head of the femur (thighbone) forms the ball, which fits into the acetabulum (a cup-shaped socket in the pelvis). Ligaments connect the ball to the socket and usually provide tremendous stability to the joint. The hip joint is normally very sturdy because of the fit between the femoral head and acetabulum as well as strong ligaments and muscles at the joint. All of the various components of the hip mechanism assist in the mobility of the joint.

Damage to any single component can negatively affect range of motion and ability to bear weight on the joint. Orthopedic degeneration or trauma – those conditions affecting the bones in the hip joint – can necessitate total hip replacement , partial hip replacement or hip resurfacing . Bones of the hip joint Normal Hip Joint vs. Arthritic Hip Joint The femur is the upper leg bone or thigh. It is the largest bone in the body. At the top of the femur is a rounded protrusion which articulates with the pelvis. This portion is referred to as the head of the femur, or femoral head. There are two other protrusions near the top of the femur, known as the greater and lesser trochanters. The muscles involved in hip motion are attached to the joint at these trochanters. The acetabulum is a concave area in the pelvis, into which the femoral head fits. The pelvis is a girdle of bones, connected at the front by cartilage pad, called the pubis, and at the back by the lowest four fused vertebrae (the sacrum). The sacro-iliac joints are located where the sacrum meets the pelvis.

The bone surfaces of the femoral head and acetabulum have a smooth durable layer of articular cartilage that cushions the ends of the bones and allows for smooth movement. Hip joint capsule or socket Hip capsule (socket) illustration (image courtesy of: Smith & Nephew ) You may hear your hip surgeon refer to the capsule or socket, when describing the structure of the hip joint. The joint capsule is a thick ligamentous structure surrounding the entire joint. Inside the capsule, the surfaces of the hip joint are covered by a thin tissue called the synovial membrane. This membrane nourishes and lubricates the joint. Ligaments As noted above, the stability of the hip joint is directly related to its muscles and ligaments. The most notable ligaments in the hip joint are: Iliofemoral ligament, which connects the pelvis to the femur at the front of the joint. It keeps the hip from hyper-extension Pubofemoral ligament, which attaches the most forward part of the pelvis known as the pubis to the femur Ischiofemoral ligament, which attaches to the ischium (the lowest part of the pelvis) and between the two trochanters of the femur.

Labrum The labrum is a circular layer of cartilage which surrounds the outer part of the acetabulum effectively making the socket deeper to provide more stability for the joint. Labrum tears are not an uncommon hip injury. Muscle Groups The various muscles which attach to or cover the hip joint generate the hip’s movement. Gluteals: The gluteals are the muscles in your buttocks. The gluteals (gluteus maximus, gluteus minimus and gluteus medius) are the three muscles attached to back of the pelvis and insert into the greater trochanter of the femur. Quadriceps: The four quadricep muscles (vastus lateralis, medialis, intermedius and rectus femoris) are located at the front of the femur. All four attach to the top of the tibia. The rectus femoris originates at the front of the ilium.The three other quads attach around the greater trochanter of the femur and just below it. Iliopsoas: This is the primary hip flexor muscle.

The three parts of the iliopsoas attach the lower part of the spine and pelvis, then cross the joint and insert into the lesser trochanter of the femur. Hamstrings: The three muscles at the back of the thigh are called the hamstrings. All three attach to the lowest part of the pelvis. Groin muscles: The groin or adductor muscles attach to the pubis and run down the inside of the thigh. The Hip Bone - Ilium - Ischium - Pubis - TeachMeAnatomy By Anatomography [CC-BY-SA-2.1-jp], via Wikimedia Commons Fig 1.0 – Overview of the anatomical position of the hip bones. The two symmetrical hip bones (also known as the innominate bones, or pelvic bones) are part of the pelvic girdle, the bony structure that attaches the axial skeleton to the lower limbs (for more information about the anatomy of the pelvic girdle, click here ) The hip bones have three articulations: Sacroiliac joint – articulation with sacrum. Pubic symphysis – articulation with the corresponding hip bone. Hip joint – articulation with the head of femur.

In this article, we shall look at the osteology of the hip bones – their constituents, bony landmarks, and applied anatomy. Fig 1.2 – The hip bone of a 5 year old, with triradiate cartilage still present. Composition of the Hip Bone The hip bone is made up of the three parts – the ilium, pubis and ischium. Prior to puberty, the triradiate cartilage separates these constituents. At the age of 15-17, the three parts begin to fuse. Their fusion forms a cup-shaped socket known as the acetabulum, which becomes complete at 20-25 years of age. The head of the femur articulates with the acetabulum to form the hip joint . We shall now look at the individual parts of the hip bone, and their respective bony landmarks. The Ilium © 2015-2017 TeachMeAnatomy.com [CC-BY-NC-ND 4.0] Fig 1.3 – View of the anterior and interior surfaces of the ilium The superior part of the hip bone is formed by the ilium, the widest and largest of the three parts.

The body of the ilium forms the superior part of the acetabulum. Immediately above the acetabulum, the ilium expands to form the wing (or ala). The wing of the ilium has two surfaces. The inner surface is concave, and known as the iliac fossa, providing origin to the iliacus muscle. The external surface is convex, and provides attachments to the gluteal muscles. Hence it is known as the gluteal surface. The superior margin of the wing is thickened, forming the iliac crest. It extends from the anterior superior iliac spine to the posterior superior iliac spine. Muscles attaching to the Ilium: – Gluteal muscles attach to the external surface of the Ilium at the anterior, posterior and inferior gluteal lines. The iliacus muscle attaches medially at the iliac fossa. Fig 1.4 – View of the external surface of the ilium Clinical Relevance: Anterior Superior Iliac Spine The anterior superior iliac spine (ASIS) is an important landmark, serving as the attachment site of the inguinal ligament, which runs from the ASIS to the pubic tubercle.

Midway along the inguinal ligament, the femoral artery can be palpated, with the femoral vein lying medially. In clinical practice, a patient’s “true” leg length is measured from the ASIS to the medial malleolus at the ankle joint. This is distinct from “apparent” leg length, which is measured from the umbilicus to the medial malleolus. True leg length discrepancy can seen in various hip disorders. The Pubis The pubis is the most anterior portion of the hip bone. It consists of a body and superior and inferior rami (branches). The body is located medially, articulating with its opposite pubic body, at the pubic symphysis. The superior ramus extends laterally from the body, forming part of the acetabulum. The inferior ramus projects towards, and joins the ischium. Together, the two rami enclose part of the obturator foramen, through which the obturator nerve, artery and vein pass through to reach the lower limb.

© 2015-2017 TeachMeAnatomy.com [CC-BY-NC-ND 4.0] Fig 1.6 – Anterior view of the pelvic girdle. Note how the pubis contributes greatly to the obturator foramen The Ischium The posterioinferior part of the hip bone is formed by the ischium. Much like the pubis, it is composed of a body, an inferior and a superior ramus. © 2015-2017 TeachMeAnatomy.com [CC-BY-NC-ND 4.0] Fig 1.7 – Parts of the ischium. The inferior ischial ramus combines with the inferior pubic ramus forming the ischiopubic ramus which encloses part of the obturator foramen. The posterorinferior aspect of the ischium forms the ischial tuberosities and when sitting, it is these tuberosities on which our body weight falls. On the posterior aspect of the ischium there is an indentation known as the greater sciatic notch, with the ischial spine at its most inferior edge.

Two important ligaments attach to the ischium: The sacrospinous ligament runs from the ischial spine to the sacrum, thus creating the greater sciatic foramen through which lower limb neurovasculature (including the sciatic nerve) transcends. The sacrotuberous ligament runs from the sacrum to the ischial tuberosity, forming the lesser sciatic foramen. Clinical Relevance: Fractures of the Pelvic Bones By James Heilman, MD [CC-BY-SA-3.0], via Wikimedia Commons Fig 1.7 – Acetabular fracture denoted with an arrow There are two common ways of fracturing the pelvic bones: Direct trauma to the pelvic bones, for example from a vehicular accident. Forces transmitted from the lower limb, for example a heavy fall on the feet. Fractures often occur at the weaker points of the bones. These are the pubic rami, the acetabulum or in the region of the sacroiliac joint. A common complication of pelvic fractures is soft tissue injury. In particular, the bladder and urethra are at high risk of damage.

Rate This Article Hip Conditions - HSS.edu Hip Conditions Seeing a Physician at the Center for Hip Preservation The Hip Joint The hip joint is a “ball and socket” joint located where the thigh bone (femur) meets the pelvic bone. The upper segment (“head”) of the femur is a round ball that fits inside the cavity in the pelvic bone that forms the socket, also known as the acetabulum. The ends of the bone are covered with a smooth, cushioning layer called articular cartilage. The articular cartilage is what allows the bones to glide smoothly. While the cartilage covers the entire head of the femur, the acetabulum cartilage is in the shape of a horseshoe with a depression (fossa) in the center of the socket. This fossa contains soft tissue and a ligament connecting the femoral head to the socket. The socket has a rim of rubbery fibrocartilage called the labrum. The labrum acts as a gasket, sealing in joint fluid and maintaining lubrication and nutrition. In addition, numerous tendons surround the hip, as well as bursae, which are lubrication "cushions" where soft tissues glide over bony prominences.

Many factors can cause hip pain or hip problems that would lead someone to seek medical treatment from an orthopedist. These include abnormal anatomy that a person is born with and conditions that develop during the growth and development of the bones grow in childhood or adolescence. Trauma, as well as the wear and tear that occurs with aging can all lead to progressive arthritic changes. Hip pain in athletes is commonly the result of a muscle strain or tendinitis. The diagnosis and management of hip injuries has evolved substantially with the advancement in diagnostic tools such as magnetic resonance imaging and with new minimally invasive techniques and in hip arthroscopy.

Question: What is the ring of bones at the hip called?
Answer: Pelvic girdle