Muscles of the Gluteal Region
DR. NIVIN SHARAF MD
LMCC
Objectives
• Identify the bony landmarks of the pelvis and hip on the articulated
skeleton and bones. Include: pelvis (ilium, ischium, pubis, iliac crest, iliac
fossa, anterior superior iliac spines, pubic tubercle, pubic crest, acetabulum,
obturator foramen, greater and lesser sciatic notches, ischial spine,
sacroiliac joint, greater and lesser sciatic foramina, ischial tuberosity), femur
(head, neck, shaft, greater and lesser trochanters, intertrochanteric line and
crest, linea aspera).
• Explain how the anatomical position affects the muscle function. .
• Locate the piriformis muscle and the suprapiriform and the infrapiriform
spaces.
• Identify the superior gluteal nerve in the suprapiriform space and the sciatic
and inferior gluteal nerves emerging via infrapiriform space.
• . Summarize the muscles of gluteal region and thigh in terms of their
location, origin, insertion, nerve supply and actions.
Bony Skeleton
FYI
FEMUR
Anterior.
greater
trochanter
head
neck
lesser
trochanter
intertrochanteric
line
lateral
epicondyle
lateral
condyle
medial
epicondyle
medial
condyle
Proximal:
-head,
-fovea
-neck,
-greater + lesser
trochanters,
-intertrochanteric
line + crest
-gluteal
tuberosity
-linea aspera.
Distal:
-supracondylar
lines
-epicondyles,
-condyles
-adductor
tubercle
Posterior.
intertrochanteric
crest
linea aspera
adductor
tubercle
gluteal
tuberosty
supracondylar
lines
Sciatic
foramen
Movements
of Hip Joint
Internal
rotation
External
rotation
Gluteal region
• Gluteal muscles: a-Gluteus maximus
b-Gluteus medius
c-Gluteus minimus
• Tensor fasciae latae -iliotibial tract.
• Small lateral rotators of thigh.
• Sciatic and posterior cutaneous nerve of thigh.
• Superior and inferior gluteal ARTERIES.
Gluteus Maximus
gluteus maximus
Gluteus
maximus
Gluteal region:
iliotibial tract
Tensor
Fasciae
Latae
-Gluteus maximus
(most powerful
extensor,
also lateral rotator)
Insertion:
Gluteal tuberosity
+
Iliotibial tract (band)
Lateral View
Posterior View
Gluteus Maximus
FYI
Gluteus Maximus and Tensor Fascia Lata insert into Iliotibial Tract
- Iliotibial tract is a thickening of the deep fascia (fascia lata) that extends from the ilium to the
tibia.
- Tension from contraction of gluteus maximus and tensor fasciae latae stabilizes the lower limb
as a weight-bearing column.
Tensor Fascia Lata
Lateral
Posterior
Illio Tibial Tract (Band)
Is the thickened lateral
part of fascia latae.
Receive insertions of:
1- tensor fasciae l.
2- superf ¾ of gluteus
maximus.
Attached to oblique ridge
on the front of lat condyle
of tibia.
Stabilize femur on tibia
during standing.
Gluteus Medius
Extends, Abducts and Medial and Lateral rotations (Ant and posterior fibers)
helps to keep the pelvis level when the opposite leg is raised during activities such as running,
Walking, or standing on one leg
Gluteus Minimus
Posterior View
Small Lateral Rotators of Thigh
1.
Piriformis .
2.
Obturator internus.
3.
Superior gemillus
4.
inferior gemillus
5.
Quadratus femoris.
Action
• Gluteus maximus:1- main extensor of hip.
2- lateral rotation of hip
3- Maintain knee joint in
Extension through the iliotibial tract.
• gluteus medius, gluteus minimus, tensor fascia
latae :
1- extension of hip
2- abduction of hip
3-medial rotation (anterior fibers)
4-contract during walking to prevent tilting of
pelvis.
Nerve supply
• Inferior gluteal nerve → gluteus maximus.
• Superior gluteal nerve →gluteus medius.
gluteus minimus.
tensor fascia latae
Intrinsic muscles
• Infra and supra Piriformis
space
Superior gluteal nerve
Lateral and Medial Rotation of the hip
gluteus medius
gluteus
maximus
superior
gamellus
inferior
gamellus
gluteus minimus
Deep to gluteus maximus:
piriformis -abductors:
gluteus medius
obturator
gluteus minimus
internus
(anterior fibres medially rotate)
quadratus
femoris
-lateral (external) rotators:
piriformis
obturator internus
(associated gemelli)
quadratus femoris
[obturator externus is also a
lateral rotator]
Gluteus medius and minimus: abduction of femur and stabilization of pelvis
Normal
Positive sign
Trendelenburg Sign.
*
Loss of abductor function
(gluteus medius & minimus)
causes the pelvis to tilt down
when supporting the body
on the affected side (*).
(I.e. damage to superior
gluteal nerve).
This function of these
muscles is called
“stabilization of the pelvis”.
Superior and Inferior Gluteal Nerves
Superior:
Gluteu Medius
Gluteus Minimus
Inferior
Gluteus Maximus
QUIZ
Intragluteal Injections
• What?
• Why?
Avoid Sciatic Nerve Injury
Sciatic Nerve (L4-S3)
• Thickest nerve in
the body
• About 2cm in
diameter
• L4, L5, S1, S2, and
S3 Inside the
pelvis
• Leave through
greater sciatic
Foramen, below
piriformis.
FYI!
Sciatic Nerve Variations!
Muscle
Piriformis
Origin
Insertion
N supply
Action
Lateral
rotation
3 middle
Sacral
peices
Spine of
ischium
Upp border S1,2
of g
trochanter
Inf
gemillus
Upp margin
of ischial
tuberosity.
T of obt. int N to
quadratus f
Obturator
internus
Obturator
Membrane
Med surf of N to obturator Lateral
g
int
rotation
trochanter
Quad fem
Ischial tuber
Quadrate t
Sup
gemillus
T of obt. int N to obturator Lateral
int
N to
quadratus f
rotation
Lateral
rotation
Lateral
rotation
QUIZ
References
•
•
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www.netteranatomy.com
www.studentconsult.com
www.google.com
Gray’s Anatomy for students