[Music] hipbone the hipbone is a large irregular flat bone which is situated in the pelvic region two hip bones along with the sacrum and coccyx formed the bony pelvis it presents a cavity in its lateral side known as the acetabulum which articulates with the head of the femur to form the hip joint it has three separate parts ilium pubis ish Kim during early life the three bones are separated by a y-shaped cartilage which later ossifies the place of union being in the walls of the acetabular cavity ilium it is the flat expanded part above the acetabular cavity it has the following parts two ends upper and lower three borders anterior posterior and menial three surfaces gluteal iliac fossa and pelvic upper end this is also known as the iliac crest it is elongated and expanded it makes up the upper border of the ilium the highest point of the iliac crest is situated at a level between the third and fourth lumbar vertebrae when looked at in the horizontal plane the crest is concave inward anteriorly and convex inward posteriorly anterior superior iliac spine it is a projection situated at the anterior end of the iliac crest posterior superior iliac spine is a projection situated at the posterior end of the iliac crest the crest is divided into ventral two-thirds and dorsal one-third segments ventral segment this presents with outer lip inner lip and an intermediate segment the outer lip presents with a tubercle about five centimeters behind and above the anterior superior iliac spine and is known as the tubercle of the iliac crest the intermediate area lies between the outer and inner lips dorsal segment it extends from its junction with the ventral two-thirds till the posterior superior iliac spine it presents an inner and outer surface separated by a ridge lower end it is smaller and forms about 2/5 of the articular surface of the acetabulum anterior border it extends from the anterior superior iliac spine till the acetabulum a small notch is present just below the spine for the lateral cutaneous nerve of the thigh anterior inferior spine is a projection in the lower part posterior border it extends from the posterior superior iliac spine to become continuous with the posterior border of the ischium from above downwards it presents with posterior inferior spine greater sciatic notch hql spine lesser sciatic notch medial border it extends downwards from the iliac crest till the iliopubic eminence it separates the iliac fossa from the sacral pelvic surface its lower part is smooth round and is called the arcuate line gluteal surface it is the outer surface of the bone it is convex anteriorly and concave posteriorly this surface is bounded above by the iliac crest below by the upper border of acetabulum in front by the anterior border and behind by the posterior border it becomes continuous with the posterior surface of the ischium behind the acetabulum it is split into four spaces by three lines posterior gluteal line it is the shortest line which extends from the outer lip of the iliac crest five centimeters anterior to the posterior superior iliac spine till a point right in front of the posterior inferior iliac spine anterior gluteal line it is the longest line which extends from the middle of the upper border of the greater sciatic notch to become continuous with the outer lip of the iliac crest inferior gluteal line it extends from above and behind the anterior inferior iliac spine and runs down and back till the upper part of the greater sciatic notch iliac fossa it is an area which lies between the anterior border in front medial border behind an iliac crest above it is smooth and concave it presents for the nutrient foramen in its posterior inferior part which transmits the nutrient artery the nutrient artery is derived from the iliolumbar artery a groove is present between the anterior inferior iliac spine and iliopubic eminence which lodges the iliopsoas tendon sacral pelvic surface it is situated behind the medial border and is divided into two parts sacral part and the pelvic part sacral part presents with an articular surface anteriorly and the iliac tuberosity posteriorly auricular surface it lies below an anterior to the iliac tuberosity it resembles the shape of a pinna of the year hence the name it articulates with the auricular surface of the sacrum iliac tuberosity is a rough area below the iliac crest pelvic surface it lies below an anterior to the auricular surface it is smooth and is continuous with the pelvic surface of the ischium preauricular sulcus is a groove which is situated in front of the auricular surface and along the lateral margin of the greater sciatic notch pubis it forms the anterior part of the hip bone and articulates with the opposite bone forming the symphysis pubis it also forms an anterior 1/5 of the acetabulum parts body superior ramus and inferior ramus body it connects the superior and inferior ramus it has three surfaces one border the pubic crest and the pubic tubercle anterior surface for four words downwards and laterally the posterior surface is smooth and forms the anterior wall of the bony pelvis its upper part is related to the urinary bladder symphyseal surface is rough and oval it articulates with a simple surface of the opposite pubis to form a secondary cartilaginous joint it is covered by high lean cartilage pubic crest is the blunt upper border of the pubis pubic tubercle is a rounded projection at the lateral end of the pubic crest it is crossed by the spermatic cord and males or round ligament of the uterus in females superior ramus it arises from the superior lateral angle of the body of the pubis and passes above the obturator foramen and unites with the ilium at the iliopubic eminence it is triangular and cross-section hence has three borders and three surfaces borders operator crest it is the rounded margin which extends from the pubic tubercle till the acetabular cavity it separates the obturator from the pectineus surface PEC tinea line it is a sharp border which starts at the posterior part of the pubic tubercle and extends backwards to become continuous with the arcuate line it separates the pelvic from the PEC tinea surface inferior border is sharp and forms the upper boundary of the obturator foramen surfaces pectineus surface it faces anteriorly and lies between the obturator crest and the PEC tinea line it extends from the pubic tubercle till the iliopubic eminence pelvic surface it faces upwards and backwards it lies between the PEC tinea line and inferior border it is continuous with the pelvic surface of the body of the pubis the obturator surface faces downwards and backwards it lies between the obturator crest and the inferior border a groove is present on this surface which is turned into a canal by the obturator muscles and brain it transmits the obturator nerve and vessels inferior ramus it is a part of the pubic bone which extends backwards from the body and unites with the ramus of the ischium on the medial side of the obturator foramen it has two surfaces and two borders and here your surface it is continuous with the anterior surface of the body it is directed downwards forwards and laterally posterior surface it is continuous with the posterior surface of the body above and with the posterior surface of the ramus of the ischium balloon it is divided into three areas by to blunt ridges medial area intermediate area and the lateral area medial border is more prominent in males lateral border forms the medial boundary of the obturator foramen and gives attachment of the obturator membrane ashkum it forms the posterior and lower part of the hip bone it makes up about posterior 2/5 of the acetabulum parts it is made up of a body and Aramis body consists of two ends three surfaces and three borders upper end it is fused with the ilium and pubis and forms part of the acetabular cavity the lower end forms part of the ischial tuberosity Ishqiya tuberosity is situated in the lower end it is divided into upper quadrilateral and a lower triangular area upper area is divided into upper lateral part and lower medial part lower area is divided into smaller medial part and larger lateral part there is a groove above the ischial tuberosity which lodges the tendons of the obturator internus and Jem aligned femoral surface faces downwards forwards and laterally it lies between the lateral and anterior borders the dorsal surface faces upwards backwards and laterally it lies between the lateral and posterior borders it is continuous with the gluteal surface of the pelvic surface it is smooth and lies between the anterior and posterior borders the anterior border forms the posterior margin of the obturator foramen the lateral border separates the femoral surface from the ischial tuberosity it lodges the obturator externus tendon in the upper part posterior border is continuous above with the posterior border of the ileum and helps to form the greater sciatic notch each skill spine is a projection at the end of this border ramus it extends upwards forwards and medially from the body of the ischium to join the inferior ramus of the pubis it has two borders and two surfaces upper border lower border the anterior surface which is continuous with the anterior surface of the inferior ramus of the pubic bone posterior surface which is divided into three areas by to blunt ridges upper area middle area and the lower area the acetabular cavity it is a deep hollow in the hip bone which faces laterally downwards and forwards it articulates with the head of the femur all three of the hip bones contribute to the formation of the acetabular cavity pubis upper and anterior one-fifth ischium lower and posterior two-fifths ilium the rest of the cavity acetabular notch it is a gap in the inferior part of the acetabular margin the acetabular fossa is a rough area in the center of the cavity which is not articular and is covered with a pad of fat lunayt surface is a horseshoe shaped area which articulates with the head of the femur actuator foramen it is a large opening in the bone between the pubis and ishke Ambala and the acetabular in the front boundaries above and in front superior ramus and the body of the pubis below and medially Ishqiya pubic ramus behind body of the ischium a of inferior margin of the acetabulum in males it is large and oval in females it is small and triangular in the living it is covered by the obturator membrane which is attached along the margin except in the upper part for the passage of the obturator nerve and vessels from the pelvis to the time determination of the site ileum is expanded and projects up pubis faces forwards and medially above the obturator foramen acetabular cavity faces forwards downwards and laterally ossification the hip bone ossifies in three primary centers and five secondary centers the primary centers appear as follows one for the ileum at eight weeks of intrauterine life one for ischium at third month of intrauterine life one for the pubis during the fourth month of intrauterine life they fuse with each other by seven to nine years the y-shaped tri radiate cartilage fuses by 15 to 18 years the secondary centers are one for the iliac crest one for anterior inferior iliac spine one for the body of the pubis one for the ischial tuberosity and one for the ischial spine all of them appear at puberty they fuse with the main bone mass by the age of 25 years