L14: Musculo-neuro-vascular systems of gluteal region (hip and buttock) Flashcards
gluteal surface anatomy :
bony landmarks:
- anterior superior iliac spine ASIS
- pubic tubercle
- posterior superior iliac spine PSIS
- iliac crest
- greater trochanter
gluteal surface anatomy:
soft tissue features:
- gluteal cleft
- gluteal fold
- gluteal maximus
- gluteal medius
ligaments of pelvis
sacrospinous ligament:
- from sacrum to ischial spine
- stabilises sacroiliac joint
sacrotuberous ligament:
- from sacrum to ischial tuberosity
- stabilises sacroiliac joint
sacrospinous ligament and sacrotuberous ligament form
these ligaments from part of the perimeter the greater sciatic foramen and lesser sciatic foramen
movements of hip joint
Flexion and Extension
Abduction and Adduction
External and Internal Rotation
Circumduction
gluteal muscles (9)
superficial (4)=
- gluteus maximus
- gluteus medius
- gluteus minimus (deep to gluteus medius)
- tensor fasciae latae
gluteal muscles (9)
deep muscles (5) =
- piriformis
- superior gemellus
- obturator internus
- inferior gemellus
- quadratus femoris
gluteus maximus
origin:
insertion:
- most superficial muscle. covers most of other muscles. Usually covered by a thick layer of adiposity
Origin=
- ilium posterior to posterior gluteal line
- lateral part of posterior sacrum and coccyx
- sacrotuberous ligament
insertion=
- illiotibial tract
- gluteal tuberosity on posterolateral femur
gluteus maximus
innervation=
actions=
innervation:
- inferior gluteal nerve (L5, S1, S2)
Actions:
- inferior part: extends thigh at hip joint
- external (lateral) rotation of femur at hip joint
gluteus medius
origin=
insertion=
lies deep to gluteus maximus
origin:
- external iliac surface, between anterior and posterior gluteal lines
insertion:
- lateral surface of greater trochanter of femur
gluteus medius
innervation=
actions=
innervation:
- superior gluteal nerve (L5, S1)
actions:
- abducts femur at hip joint
- internally rotates femur at hip joint
- stabilises pelvis in coronal plane
gluteus minimus
origin=
insertion=
lies deep to gluteus maximus
origin:
- external iliac surface, between anterior and inferior gluteal lines
insertion:
- anterior surface of greater trochanter
gluteus minimus
innervation=
actions=
innervation:
- superior gluteal nerve (L5, S1)
actions:
- abducts femur at hip joint
- internally rotates femur at hip joint
- stabilises pelvis in coronal plane
trendelenburg sign
caused by a weakness of hip abductors
Tendelenburgs gait
*When standing on one leg, hip abductors are unable to counteract gravity.
*Opposite side of pelvis tilts inferiorly.
*This means the other leg does not have sufficient clearance to swing forward for next step.
*In order to compensate and provide additional clearance for leg swing, patient leans to same side as the weak hip abductors.
*This elevates the pelvis and allows the leg clearance to swing for next step.
*In addition, often patients will swing their leg out and forward in order to achieve greater clearance.
Tensor Fasciae Latae
origin=
insertion=
Origin: ASIS + Anterior Iliac crest
Insertion: illiotibial tract (which inserts into lateral tibial condyle)
Tensor Fasciae Latae
Innervation=
Actions=
Innervation: Superior Gluteal Nerve (L5-S1)
Actions:
- abduct, flexes, internally rotates thigh at hip joint
- tightens iliotibial tract which stabilises knee while leg is extended
- keeps pelvis level when standing on ipsilateral limb
Piriformis
Origin=
insertion=
origin:
- anterior surface of sacrum
- sacrotubureous ligament
Insertion:
- exits pelvis through greater sciatic foramen
- superior border of greater trochanter
Piriformis
innervation=
actions=
innervation:
- nerve to piriformis (S1/S2)
Actions:
- externally rotates an extended thigh
- abducts a flexed thigh
- stabilises femoral head in acetabulum
Superior Gemellus
origin=
insertion=
origin: ischial spine
insertion: medial surface of greater trochanter of femur
Superior Gemellus
Innervation=
Actions=
innervation: nerve to obturator internus (L5,S1)
Actions:
- externally rotates an extended thigh
- abducts a flexed thigh
- stabilises femoral head in acetabulum
Obturator internus
origin=
insertion=
Forms triceps coxae with gemelli muscles
Origin: inner surface of obturator membrane and its bony boundaries
Insertion: medial surface of greater trochanter of femur
Obturator internus
Innervation=
Actions=
innervation: Nerve to obturator internus (L5,S1)
Actions:
- externally rotates an extended thigh
- abducts a flexed thigh
- stabilises femoral head in acetabulum
Inferior Gemellus
origin=
insertion=
origin: ischial tuberosity
insertion: medial surface of greater trochanter of femur
Inferior Gemellus
innervation=
actions=
Innervation: nerve to quadratus femoris (L5,S1)
Actions:
- externally rotates an extended thigh
- abducts a flexed thigh
- stabilises femoral head in acetabulum
Quadratus Femoris
origin=
insertion=
Origin: lateral border of ischial tuberosity
Insertion: quadrate tubercle on intertrochanteric crest of femur
Quadratus femoris
innervation=
actions=
innervation: nerve to quadratus femoris (L5,S1)
Actions:
- external rotation of thigh at hip joint
- stabilises femoral head in acetabulum
Cutaneous Nerves of the gluteal region
superior, middle and inferior clunial (cluneal) nerves:
- superior: posterior rami of L1-3
- middle: posterior rami of S1-3
- inferior: anterior rami of S2-3
lateral branch of the iliohypogastric Nerve also supplies part of the lateral buttocks
The sciatic nerve
- is the continuation of the lumbrosacral plexus and is the major nerve of the lower limb
- carries motor signals to muscles
- carries sensory signals from skin
- is vulnerable to compression which causes sciatica
Sciatica
can be understood as sciatic nerve impingement (compression)
patients will report a shooting pain that shoots down the back of their leg
Treated with:
generally with rest, anti-inflammatories, muscle relaxants
Sciatic nerve - anatomical variation
- sciatic nerve spits into tibial and fibular nerves before exiting the greater sciatic foramen
- 12.2% of people have common fibular nerve passing through piriformus
- 0.5% of people have common fibular nerve passing superior to piriformis - vulnerable to injury
arterial supply to lower limb
Heart,
Descending Aorta,
Common Iliac Artery
- internal iliac artery > supplies gluteal region and pelvis region
- external iliac artery > goes on to become femoral artery and supply thigh, leg, foot
arterial supply to gluteal region
heart,
descending aorta,
common iliac artery,
internal iliac artery,
- superior gluteal artery
- inferior gluteal artery
superior and inferior gluteal arteries supply the superior / inferior gluteal region respectively
Venous drainage of the lower limb
right atrium of heart
^
inferior vena cava
^
common iliac vein
^ ^
internal iliac vein external iliac vein
^^ ^
superior gluteal common femoral
vein and inferior vein (main thigh
gluteal vein vein)
venous drainage of the gluteal region
The gluteal region is drained by the Superior and Inferior Gluteal Veins.
These run beside the Superior and Inferior Gluteal Arteries but carry deoxygenated blood in the opposite direction.
The Superior and Inferior Gluteal veins pass through the greater sciatic foramen on either side of piriformis and drain into the Internal Iliac Vein.
The Internal Iliac Vein drains into Common Iliac Vein which subsequently drains into the Inferior Vena Cava.
