Week 8 Anatomy

Bony Pelvis

Identify the following on the bone/model and pictures

  • Ilieum
    • Crest
    • Ala/fossa
    • ASIS
    • AIIS
    • Obturator foreamen
    • Sacroiliac joint
    • Posteriorly – anterior, posterior and inferior gluteal line, ischial spine, greater and lesser sciatic notch
  • Ischium
    • Tuberosity
    • Ischial spine
    • Rami
  • Pubis
    • Crest
    • Tubercle
    • Rami
    • Symphysis

All three bones meet at the acetabulum


 Hip joint:

  • Between Acetabulum of bony pelvis and head of femur – good bony congruence
  • Stabilised by fibrocartilage labrum, iliofemoral, ischiofemoral and pubofemoral ligaments – anteriorly
  • Hip abductors and lateral rotators give dynamic support posteriorly
  • Ball and socket synovial joint – flexion/extension, abduction/adduction, internal and external rotation
  • Capsule – intertrochanteric line ant and intertrochanteric crest posteriorly
  • Nerve- femoral, obturator and superior gluteal nerves
  • Blood supply – lateral and medial circumflex femoral arteries(profunda femoris), artery to head of femur(obturator)
  • Ishiofemoral ligament is weakest
  • Iliofemoral is strongest ligament of hip.


Adductor muscles of the thigh

Innervated by obturator L2-4

  • Gracillus
    • Most medial
    • From pubic body and inferior ramus  to medial tibia via pes anserinus.
  • Adductor Brevis
    • Behind adductor longus.
    • From anterior and inferior aspect of pubic body to linea aspera
    • Obturator’s ant and posterior division run ant and posterior to this.
  • Adductor longus
    • Most anterior
    • From anterior aspect of pubic body to linea aspera
  • Adductor magnus
    • Strongest adductor
    • Hamstring part supplied by tibial part of sciatic nerve- has attachment to ischial tuberosity to adductor tubercle.
    • Most posterior of adductors – from inferior pubic and ischial rami to whole length of linea aspera and gluteal tuberosity.
  • Obturator externus
    • From external surface of obturator membrane to posterior aspect of greater trochanter.


Femoral triangle

  • Borders
    • Superiorly – inguinal ligament
    • Medially – adductor longus
    • Laterally – sartorius
    • Floor- iliopsoas, pectineus, adductor longus
    • Roof – fascia lata
  • Contents
    • Laterally – femoral nerve(outside sheath), then femoral artery then femoral vein–> femoral canal.
    • Great saphenous vein inserts here.
    • Deep artery of thigh(profunda femoris) leaves here posterior to femoral artery and adductor longus.


Femoral nerve

  • Superficial
    • 2 cutaneous – intermediate and medial femoral cutaneous nerve
    • 2 muscular – sartorius, pectinus
  • Deep
    • Saphenous  – cutaneous
    • Muscular – 4 branches to quadriceps.
  • Supply to: psoas, iliacus, pectineus, sartorius, rectus femoris, vastus lateralis and vastus medius.


Femoral artery

  • 4 superficial branches and profunda femoris
    • Superficial pudendal
    • Deep pudendal
    • Superficial epigastric
    • Superficial circumflex iliac
  •  Distally – descending genicular arteries
  • External Iliac–> IL–> common femoral artery in femoral triangle–> fives off, four branches and PF–> exits femoral triangle and continues down anterior surface of thigh–> Finishes as popliteal artery at adductor hiatus in adductor magnus.


Profunda femoris artery:

  • Course – arises posterio/laterally from femoral artery in femoral triangle 1-5cm below inguinal ligament–> behind adductor longus–>perforating arteries through magnus–> wrap around posterior femur on medial side
  • Branches – lateral and medial circumflex arteries, perforating arteries.



Gluteal region:


  • Gluteus medius
    • ilium between ant and post gluteal line–> lateral greater trochanter – hip abduction and medial rotation (sup gluteal nerve L5S1)
  • Gluteus Minimus
    • Ilium between ant and inferior gluteal line –> and greater trochanter – hip abduction and medial rot (sup gluteal nerve L5S1)
  • Gluteus maximus
    • ilium posterior to post gluteal line, SI joint, coccyx–> gluteal tuberosity+iliotibial tract – extend hip, lateral rotation. Inferior gluteal nerve S1S2
  • Tensor fascia lata
    • Asis and ant iliac crest to iliotibial tract (sup gluteal nerve L5S1)
  • Piriformis
    • Ant sacrum + sacrotuberous ligament –> sup greater trochanter – lateral rotate extended thigh, abduct flexed thigh, hip stabiliser (ant rami of S1, S2)
  • Obturator internus
    • Internal surface of obturator membrane to medial greater trochanter
    • lateral rotate extended thigh, abduct flexed thigh, hip stabiliser
  • Superior Gamelli
    • Ischial spine to medial greater trochanter
    • lateral rotate extended thigh, abduct flexed thigh, hip stabiliser
  • Inferior Gamelli
    • Ischial tuberosity to medial greater trochanter
    • lateral rotate extended thigh, abduct flexed thigh, hip stabiliser
  • Quadratus femoris
    • Lateral border of ischial tuberosity to quadrate tubercle on intertrochanteric crest
    • Laterally rotate thigh



  • Clunial nerves supply skin of gluteal region
  • All deep nerves leave via greater sciatic foramen, except for superior gluteal nerve all come under piriformis
  • Sciatic nerve – emerges under piriformis and travels deep to hamstrings in thigh. Supplies posterior thigh only, nothing in gluteal region
  • Pudendal – anterior rami of S2-4, enters perineum through lesser sciatic foreamen



  • Trochanteric anastomosis:
    • Circumflex femoral arteries from profunda femoris anastamose and provides blood supply to head of femur. Medial is the most important supply to head and neck of femur via retinacular arteries.


Hamstring muscles

common origin ischial tuberosity deep to gluteus maximus. Innervated by tibial part of sciatic nerve. Extend hip and flex knee. (L5S1)

  • Semitendinosis – insert with pes anserinus in medial tibia. Deep to semimembranosis.
  • Semimembranosis – posterior part of medial condyle of tibia
  • Biceps femoris  – insert in head of fibula. Short head is from line aspera.


Sciatic nerve in thigh.

  • Splits into tibial and common fibular at top of popliteal fossa