1

GLUTEAL REGION

- Quadrilateral in shape Covers the:

o Iliac crest (at the level of L4): highest point of the iliac bone

o Anterior Superior Iliac Spine (ASIS) o Posterior Superior Iliac Spine (PSIS) o Greater sciatic notch o Lesser sciatic notch o Ischial tuberosity

BOUNDARIES

Above: Iliac crest Below: Gluteal maximus Medial: Lateral margin of the sacrum and the coccyx Lateral: *Tensor fascia latae muscle

SURFACE ANATOMY Buttock (*Natis)

- Smooth rounded elevation - More developed in females especially in pregnancy

stage. The more developed it is the sexier you are. Natal cleft

- Deep fissure dividing the 2 buttocks - Boundary between your 2 buttocks

Fold of the buttock

- Equivalent of *Inferior groove of gluteus maximus. Due to bulging of the gluteus maximus and fatty maximus

CUTANEOUS NERVES

- Derived from posterior primary rami and partly from anterior primary rami of spinal nerves

- Three twigs from first 3 lumber nerves and 3 from first sacral nerves ***MEMORIZE!!!

- Anterior primary rami of spinal nerve is derived from: Lateral cutaneous branch of iliohypogastric

nerve Lateral cutaneous branch of lateral cutaneous

nerve of the thigh Posterior branch of lateral cutaneous nerve of

thigh Perforating cutaneous branch of S4

SUPERFICIAL LYMPH VESSELS

- Usually goes in the lateral lymph glands of the superficial inguinal group

FASCIA OF THE BUTTOCK

*Superficial fascia - Thick, especially in women, and impregnated with

large quantities of fat - Loaded with fat and numerous small cutaneous

nerves - Thickens over lower and upper margins of gluteus

maximus. It actually covers gluteus maximus - Rough and stingy over ischial tuberosity: cushion in

sitting position. The more developed it is the more comfortable you are in sitting.

*Deep fascia - Attached to the iliac crest

Gluteus Medius - dense, opaque, pearly white deep fascia

Gluteus Maximus - thin, transparent - More developed covering the gluteus medius

although it also goes upward and covers the gluteus maximus

(11 M) The Gluteal Region: Landmarks, Vessels, and Nerves

Dr. LAYGO| MAR 25, 2015 ANATOMY

Natal

cleft

Gluteal

fold

Buttocks/ Natis

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GLUTEAL MUSCLES: GLUTEUS MAXIMUS

- Rhoimboid; most massive structure in the human body

- Bulging of the buttock ORIGINS:

Posterior gluteal surface of the ileum

Dorsal aspect of sacrum and coccyx

Posterior surface of sacrotuberous ligament INSERTIONS:

Upper part of femoral shaft

Iliotibial tract (3/4: majority attachment)

Gluteal tuberosity UPPER BORDER:

o Landmark: Line which runs parallel with lower border; exits from PSIS to a point 2 inches above the greater trochanter

ACTION: *Great extensor of the thigh

*Synovial bursae: underneath G.maximus

1. Located between muscle and ischial tuberosity

2. Between muscle and greater trochanter 3. Between gluteus and upper vastus lateralis

Refer to the preceding image THE GLUTEAL REGION, POSTERIOR ASPECT. a. The deep relations of the Gluteus Maximus. The Sciatic

nerve usually emerges inferior to the piriformis and lies on a succession of lateral rotators.

b. Intramuscular injection. An intragluteal injection may be made safely in the area between the second and third fingers.

PIRIFORMIS

- One of the doors/gateways to the gluteal region. The other door is the greater sciatic foramen.

- Most obvious/unique muscle of the gluteal region ORIGINS:

Anterior surface of S2, S3, and S4 vertebra

In between sacral foramena

Upper part of the greater sciatic notch and sacrotuberous ligament

INSERTION:

Highest point of greater trochanter ACTION: *Extensor and lateral rotator of the femur INNERVATION: *S1

2 SPACES:

Infrapiriformic space: structures that exits from this space (lateral to medial)

Structures that pass through: 1. Sciatic nerve 2. *Inferior gluteal nerve 3. Posterior cutaneous nerve of thigh 4. Inferior gluteal artery 5. Nerve to obturator internus 6. Internal pudendal vessels 7. Internal pudendal nerve to the alcocks

canal

Suprapiriformic space: above the piriformis in the greater sciatic foramen

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Structures that pass through: 1. Superior gluteal vessels

a. *Superior gluteal artery - branches into superficial and deep branches:

i. *Superficial branch - supplies gluteus

maximus

ii. *Deep branch - supplies gluteus medius and gluteus minimus

b. *Superior gluteal vein

2. Superior gluteal nerves

- innervates the 3 abductors and medial rotators of the hip joint: gluteus medius, gluteus minimus and tensor fascia latae

The arrangement of the structures emerging from the GREATER SCIATIC FORAMEN. The foramen gives exit to the Piriformis, to SEVEN NERVES (sciatic, posterior femoral cutaneous, superior gluteal, inferior gluteal, pudendal, nerve to the obturator internus, and nerve to the quadratus femoris), and to THREE GROUPS OF VESSELS (internal pudendal, superior gluteal, and inferior gluteal)

***MINI QUIZ ON LAST PAGE

Other gluteal muscles (See table on the next page): ***READ!!!

Gluteus medius Gluteus minimus Gemelli muscles Obturator internus Quadratus femoris Obturator externus

4

5

MINI QUIZ!

1. This nerve innervates the gluteus maximus muscle.

2. The deep branch of the superior gluteal artery supplies this 2 muscles: ___a___ and ___b___?

3. The fold of the buttock is equivalent to the ______________ internally.

4. It is the lateral boundary of the gluteal region.

5. Nerve supply of piriformis is derived from what vertebral level?

6. SPECIFIC artery that supplies the gluteus maximus muscle.

7. Origin of Quadratus Femoris muscle.

8. Insertion of Tensor Fasciae Latae muscle.

9. Action of Gluteus Maximus muscle

10. Fill in the blanks: The following muscles ( ___a___, Superior Gemellus, ___b__, Obturator Externus, __c__, Obturator Internus) exert their action by? ___d____

- THE END -

GOOD LUCK AND GOD BLESS

NOTE TAKERS:

- BELINGON, SARAH KATE - CAPISTRANO, VON EAGAN

PROOF READER:

- CRUZ, GINO MIGUEL F.

Theres no such thing as a painless lesson. They just dont

exist. Sacrifices are necessary. You cant gain anything

without losing something first although if you can endure that

pain and walk away from it, youll find that you now have a

heart strong enough to overcome any obstacle. Yeah, a heart

made fullmetal.

~Edward Elric, Full Metal Alchemist

//TEAMANATOMY

ANSWER KEY: 1. INFERIORGLUTEALNERVE 2. GLUTEUSMAXIMUS&MINIMUS 3.

INFERIORGROOVEOFGLUTEUSMAXIMUS 4. TENSORFASCIAELATAEMUSCLE 5. S1 6.

SUPERFICIALBRANCHOFTHESUPERIORGLUTEALARTERY 7. ISCHIALTUBEROSITY 8.

ILIOTIBIALTRACT 9. EXTENSIONOFTHETHIGH 10. PIRIFORMIS, INFERIORGEMELLUS,

QUADRATUSFEMORIS. LATERALROTATIONOFTHETHIGH