The suboccipital triangle is a space located between the occipital bone and the spine of the axis. It contains the third part of the vertebral artery and the suboccipital nerve. The boundaries of the triangle include the rectus capitis posterior minor and major muscles medially, and the obliquus capitis inferior and superior muscles inferiorly. The third part of the vertebral artery runs through a groove on the posterior arch of the atlas within the triangle. The suboccipital nerve also lies between the vertebral artery and the posterior arch of the atlas.

1. SUBOCCIPITAL TRIANGLE

2. SUBOCCIPITAL TRIANGLE
SUBOCCIPITAL TRIANGLE IS A SPACE BETWEEN
THE OCCIPITAL BONE AND THE SPINE OF THE
AXIS.
THERE ARE SMALL MUSCLES FORMING THE
BOUNDARIES.
THIRD PART OF THE VERTEBRAL ARTERY IS THE
IMPORTANT CONTENT OF THIS SPACE.

3. SUBOCCIPITAL TRIANGLE
 THE FOLLOWING ARE THE LANDMARKS
 (a) SUPERIOR NUCHAL LINE
 (b) INFERIOR NUCHAL LINE
 (c) AREA BETWEEN SUPERIOR AND INFERIOR
NUCHAL LINE
 (d) AREA BELOW THE INFERIOR NUCHAL LINE
 (e) POSTERIOR TUBERCLE OF THE ATLAS
 (f) BIFID SPINE OF AXIS AND
 (g) THE TRANSVERSE PROCESS OF THE ATLAS

4. SUBOCCIPITAL TRIANGLE
 THE SUBOCCIPITAL TRIANGLE IS SITUATED IN
THE FOURTH MUSCULAR LAYER .
 THE FIRST LAYER IS TRAPEZIUS
 THE SECOND LAYER IS SPLENIUS CAPITIS
 THE THIRD LAYER IS SEMISPINALIS CAPITIS

5. SUBOCCIPITAL TRIANGLE
BOUNDARIES OF SUBOCCIPITAL TRIANGLE
MEDIALLY
RECTUS CAPITIS POSTERIOR MINOR
RECTUS CAPITIS POSTERIOR MAJOR
INFERIORLY
OBLIQUUS CAPITIS INFERIOR
OBLIQUUS CAPITIS SUPERIOR

6. SUBOCCIPITAL TRIANGLE
SUPEROLATERALLY
ROOF
SEMISPINALIS CAPITIS
FLOOR
POSTERIOR ARCH OF ATLAS
AND
POSTERIOR ATLANTO OCCIPITAL MEMBRANE

7. SUBOCCIPITAL TRIANGLE
CONTENTS OF SUBOCCIPITAL TRIANGLE
1. THIRD PART OF VERTEBRAL ARTERY
2. SUBOCCIPITAL NERVE (PPR OF C1)
3. SUBOCCIPITAL PLEXUS OF VEINS

8. SUBOCCIPITAL TRIANGLE
THE THIRD PART OF THE VERTEBRAL ARTERY LIES
IN THE GROOVE ON THE POSTERIOR ARCH OF THE
ATLAS
SUBOCCIPITAL NERVE LIES IN BETWEEN THE
VERTEBRAL ARTERY AND THE POSTERIOR ARCH OF
THE ATLAS

9. SUBOCCIPITAL TRIANGLE
SUBOCCIPITAL NERVE
BRANCHES
1) MUSCULAR BRANCHES
SUPPLIES ALL THE SUBOCCIPITAL MUSCLES
2) COMMUNICATING BRANCH TO GREATER
OCCIPITAL NERVE
3) SENSORY BRANCH TO THE MENINGES OF THE
POSTERIOR CRANIAL FOSSA AROUND

10. SUBOCCIPITAL TRIANGLE
THE FORAMEN MAGNUM .IT HAS NO CUTANEOUS
BRANCH.
CLINICAL IMPORTANCE
IRRITATION OF THIS NERVE CAUSES OCCIPITAL
HEADACHE

11. SUBOCCIPITAL TRIANGLE
SUBOCCIPITAL PLEXUS OF VEINS LIES IN THE
FASCIA SUPERFICIAL TO THE NERVE AND THE
ARTERY.
SIGNIFICANCE
THE SUBOCCIPITAL PLEXUS OF VEINS IS
CONNECTED TO THE SIGMOID SINUS BY AN
EMISSARY VEIN THROUGH THE POSTERIOR
CONDYLAR CANAL.

12. SUBOCCIPITAL TRIANGLE
GREATER OCCIPITAL NERVE
IT IS THE THICKEST CUTANEOUS NERVE IN THE
HEAD AND NECK REGION.
ROOT VALUE IS PPR OF C2
PPR - POSTERIOR PRIMARY RAMUS

13. SUBOCCIPITAL TRIANGLE
THE ROOF OF THE SUBOCCIPITAL TRIANGLE IS
CROSSED BY GREATER OCCIPITAL NERVE.
IT EMERGES BELOW THE MIDDLE OF INFERIOR
OBLIQUE MUSCLE AND CROSSES THE
SUBOCCIPITAL TRIANGLE AND PIERCES THE
TRAPEZIUS AND EXTENDS TO SUPPLY THE SKIN OF
THE SCALP UPTO THE VERTEX.

14. SUBOCCIPITAL TRIANGLE
MUSCLES FORMING BOUNDARIES
1)RECTUS CAPITIS POSTERIOR MINOR
IT ARISES FROM THE POSTERIOR TUBERCLE OF
THE POSTERIOR ARCH OF THE ATLAS TO THE
MEDIAL PART OF THE AREA BELOW THE INFERIOR
NUCHAL LINE.

15. SUBOCCIPITAL TRIANGLE
2) RECTUS CAPITIS POSTERIOR MAJOR
IT TAKES ORIGIN FROM THE SPINE OF THE AXIS TO
THE LATERAL PART OF THE OCCIPITAL BONE
BELOW THE INFERIOR NUCHAL LINE.

16. SUBOCCIPITAL TRIANGLE
3) OBLIQUUS CAPITIS INFERIOR
IT PASSES FROM THE SPINE TO THE AXIS TO THE
TRANSVERSE PROCESS OF ATLAS

17. SUBOCCIPITAL TRIANGLE
4) OBLIQUUS CAPITIS SUPERIOR
IT EXTENDS FROM THE TRANSVERSE PROCESS
OF ATLAS TO THE LATERAL HALF OF THE AREA
BETWEEN THE INFERIOR NUCHAL LINE AND
SUPERIOR NUCHAL LINE OF THE OCCIPITAL BONE .

18. SUBOCCIPITAL TRIANGLE
OBLIQUUS CAPITIS SUPERIOR
NERVE SUPPLY IS THE SUBOCCIPITAL NERVE (PPR
OF C1)
ACTION IS TO STABILIZE THE HEAD ON ATLAS AND
AXIS AND TO ACT AS LIGAMENTS OF VARIABLE
LENGTH AND TENSION FOR THIS PURPOSE.

19. SUBOCCIPITAL TRIANGLE
SEMISPINALIS CAPITIS
THIS LONG MUSCLE PRODUCES THE ROUNDED
RIDGE AT THE SIDE OF THE MEDIAN FURROW IN
THE BACK OF THE NECK EVEN THOUGH IT IS
UNDERCOVER OR DEEP TO THE TRAPEZIUS AND
SPLENIUS CAPITIS.
ORIGIN
IT ARISES FROM THE TRANSVERSE PROCESS OF

20. SUBOCCIPITAL TRIANGLE
LOWER FOUR CERVICAL VERTEBRA AND UPPER SIX
THORARIC VERTEBRA.
INSERTION
INTO THE MEDIAL HALF OF THE AREA BETWEEN
THE SUPERIOR AND INFERIOR NUCHAL LINES OF
THE OCCIPITAL BONE.

21. SUBOCCIPITAL TRIANGLE
SEMISPINALIS CAPITIS
IS RECOGNISED BY THE FOLLOWING POINTS
1) VERTICAL FIBRES
2) PIERCED BY GREATER OCCIPITAL NERVE (PPR
OF C2)
3) THERE IS A RICH ARTERIAL ANASTOMOSIS
AROUND THE MUSCLE.
4) IT IS THE CHIEF EXTENSOR OF THE NECK

22. SUBOCCIPITAL TRIANGLE
AND IT IS A MUSCLE OF POSTURE SO IT IS RICH IN
MYOGLOBIN.

23. THANK
YOU
FOR
PATIENT
HEARING