Anatomy

1. For the students of Gulf Medical University, Ajman,
BPT
Dr. Seyed Morteza Mahmoudi,
MBBS
Gulf Medical University, Ajman

2. Contents
 Gluteal region and boundaries
 Cutaneous innervation
 Muscles of gluteal region
 Arteries of gluteal region
 Nerves of gluteal region

4. Gluteal region
 The transitional area between the trunk and the
lower extremity.
 Anatomically it is part of the trunk. Functionally
it is part of the lower extremity.
 The gluteal region includes the rounded,
posterior buttocks and the laterally placed hip
region.

5. Boundaries
 Superiorly: iliac crest (at L4),
 Medially: intergluteal cleft,
 Laterally: Greater trochanter,
 Inferiorly: gluteal fold
 The gluteal muscles form the prominent majority
of the gluteal region.

7. SUPERFICIAL FASCIA
Cutaneous Nerves
Upper-outer quadrant:
•Lateral branch of subcostal nerve.
•Lateral branches of iliohypogastric nerve
Upper-inner quadrant:
•Posterior primary rami of L1,2,3
•Posterior primary rami of S1,2,3
Lower-outer quadrant:
•Posterior divisions of lateral cutaneous nerve of thigh
Lower-medial quadrant:
•Perforating cutaneous branches of S 2,3
•Gluteal branches of posterior cutaneous nerve of thigh.

10. Muscles of the Gluteal Region

11. Muscles of the Gluteal Region
Gluteus maximus:
Largest muscle responsible
for the prominence of the
buttocks
Origin-
•Outer surface of ilium
behind posterior gluteal line
•Posterior surface of sacrum,
coccyx and sacrotuberous
ligament.
Insertion – 75% of fibres into
ilio-tibial tract – 25%(deep)
into gluteal tuberosity.

12. Nerve- inferior gluteal
nerve.
Action-
•Extensor & lateral rotator of
thigh at hip joint.
•Helps to maintain
extension at knee through
the ilio-tibial tract
•Paralysis of muscle –
inability to raise the trunk
from sitting or stooping
positions
•3 bursae are related to this muscle- trochanteric , ischial
& gluteofemoral (v.lateralis)

13. Iliotibial tract
&
Tensor fascia lata

14. Tensor fascia lata
Arises from anterior part
of iliac crest, ASIS and
notch below and inserts
into the iliotibial tract.
Nerve:
Superior gluteal nerve
Action:
Assists gluteus maximus in
keeping knee in extended
position
Muscles of the Gluteal Region

15. Muscles of the Gluteal Region

16. Gluteus medius
Posterior part covered by gluteus maximus
Origin
Outer surface of ilium b/w iliac crest above &
posterior gluteal line behind and middle gluteal
line below.
Insertion
Lateral surface of greater trochanter
Nerve – superior gluteal nerve
Action
•With G minimus and tensor fascia lata -powerful
abductor at hip.
•Anterior fibres medially rotate the thigh
•Walking and running
•Holds opposite side of pelvis horizontally when
foot is off the ground.

17. Muscles of the Gluteal Region

18. Gluteus minimus
Origin
Outer surface of ilium b/w
middle & inferior gluteal
lines
Insertion - Anterior surface
of greater trochanter
Nerve-superior gluteal nerve
Action
•With G minimus and tensor
fascia lata -powerful abductor
at hip.
•Anterior fibres medially
rotate the thigh

22. Trendelenburg test ---- used to assess hip
stability.
•The patient is asked to stand unassisted on each leg in
turn, whilst the examiner's fingers are placed on the
anterior superior iliac spines.
•The foot on the contralateral side is elevated from the
floor by bending at the knee.
•In normal function, the hip is held stable by gluteus
medius acting as an abductor in the supporting leg.
•If the pelvis drops on the unsupported side - positive
Trendelenburg sign
•The hip on which the patient is standing is painful or has
a weak or mechanically-disadvantaged gluteus medius.

23. A positive Trendelenburg test is found in:
• Any condition that brings the origin and insertion of gluteus medius together:
• subluxation or dislocation of the hip
• coxa vara (defect of head of femur)
• greater trochanter fractures
• slipped upper femoral epiphysis
• abductor paralysis or weakness e.g.:
polio
root lesion
post-operative nerve damage
muscle-wasting disease
• Any painful hip disorder which results in gluteal inhibition

24. Short Lateral Rotators of Thigh

25. Piriformis
Key muscle of gluteal region
Origin
Pelvic surface of sacrum 2nd,3rd
& 4th pieces
Sacrotuberous ligament
Insertion
Upper border of greater
trochanter
Leaves the pelvis through
greater sciatic foramen and
separates gleuteal vessels and
nerves to superior and inferior
Nerve
S1 2 anterior rami
Short Lateral Rotators of Thigh

26. Origin: from pelvic surfaces of
• Body of ischium
• Ischial tuberosity
• Ischio-pubic ramus
• Obturator membrane & fascia.
Insertion: tendon passes out of the
pelvis through the lesser sciatic
foramen and enters gluteal region
>> upper border of greater trochanter.
Obturator Internus
Nerve:
Nerve to obturator internus L5 S1 2
One ½ of muscle in pelvis
other ½ in perineum
Tendon in gluteal region
Short Lateral Rotators of Thigh

27. Gamellus superior
Origin-spine of ischium
Insertion-tendon of OBT int
Nerve- to OBT internus
Gamellus inferior
Origin-ischial tuberosity
Insertion-tendon of OBT
internus
Nerve-to Quadratus femoris
Quadratus femoris
Origin-ischial tuberosity
Insertion-quadrate tubercle
Nerve-sacral plexus
Short Lateral Rotators of Thigh

29. Arteries of Gluteal Region
Superior gluteal-from internal iliac posterior division above piriformis
Inferior gluteal-from internal iliac anterior division-below piriformis
Trochanteric anastomosis- main supply to head of femur. Retinacular
nutrient arteries pass along neck of femur to head.
Formation
1. Superior gluteal A
2. Inferior gluteal A
3. Medial Circumflex A
4. Lateral circumflex A
Cruciate anastomosis
1. Inferior gluteal
2. MCF and LCF
3. 1st perforating branch of PFA

30. Superior gluteal artery
• Branch from posterior division of the internal iliac artery
• Leaves the pelvis by passing through the greater sciatic
foramen above the piriformis muscle

31. INFERIOR GLUTEAL ARTERY
Arises from anterior division of Internal iliac artery.
• Leaves the pelvis by passing through the greater
sciatic foramen below the piriformis muscle

36. •The sacral plexus supplies
innervation to the pelvic muscles,
gluteal muscles, and perineal muscles.
It also forms the sciatic nerve.
Sacral plexus
Formed by the 4th & 5th lumbar
ventral rami (lumbosacral trunk)
and S1234
• Forms on the ventral surface of
the piriformis muscle

41. Sciatic nerve
(L4, L5, SI, S2, S3)
• Is the largest branch of the sacral
plexus and the largest nerve in body
• Consists of two separate nerves,
the common peroneal nerve and the
tibial nerve
• Leaves the pelvis through the
greater sciatic foramen below the
piriformis muscle

43. Superior gluteal nerve
(L4, L5, S1)
• Leaves the pelvis through
the greater sciatic foramen above
the piriformis muscle with the superior gluteal artery
and vein
• In the gluteal region supplies the gluteus medius, the
gluteus minimus, the tensor fasciae latae, and the hip
joint

44. Inferior gluteal nerve
(L5, S1, S2)
• Leaves the pelvis through the
greater sciatic foramen below the
piriformis muscle with the inferior
gluteal artery and vein
• In the gluteal region supplies the
gluteus maximus muscle

45. Posterior femorai cutaneous nerve
(SI, S2, S3)
• Leaves the pelvis through the greater sciatic foramen
inferior to the piriformis
• In the gluteal region descends on the posterior
surface of the sciatic nerve
• Supplies the skin of the buttocks, posterior thigh,
popliteal fossa, and external genitalia

46. Nerve to the obturator internus
(L5, S1, S2)
• Leaves the pelvis through the greater sciatic
foramen below the piriformis muscle
• In the gluteal region descends on the superior
gemellus muscle to pass below the ischial spine and
enter the lesser sciatic foramen
• Supplies the superior gemellus and obturator
internus muscles

47. Nerve to the quadratus femoris
(L4, L5, SI)
• Leaves the pelvis through the greater sciatic
foramen below the piriformis muscle and deep to the
sciatic nerve
• In the gluteal region runs anterior to the superior
and inferior gemellus and obturator internus
muscles
• Supplies the inferior gemellus and quadratus
femoris muscles

48. Pudendal nerve
(S2, S3, S4)
• Leaves the pelvis through the greater sciatic
foramen inferior to the piriformis muscle along with
the internal pudendal artery and vein
• In the gluteal region descends posterior to the
ischial spine and enters the lesser sciatic foramen
• Is distributed to the perineum and has no branches
in the gluteal region

50. Structures under cover Gluteus Maximus
1. Gluteus medius and minimis
2. Piriformis
3. Superior gamellus and inferior Gamellus
4. Tendon of obturator internus
5. Quadratus femoris
6. Adductor magnus-pubic fibres
7. Origin of hamstrings
8. Structures through greater sciatic foramen
a. Above piriformis- superior gluteal vessels and nerves
b. Below piriformis-
Sciatic n; posterior femoral cutaneous nerves
Inferior gluteal vessels & nerves
PIN structures
Nerve to OBT internus
Nerve to quadratus femoris
10. Cruciate anastamosis
11. Bursae-ischial, tronchanteric,ilial & gluteo-femoral