A. Vertebral artery.
B. Suboccipital nerve.
C. Greater occipital nerve.
D. Lesser occipital nerve.
Ans;D. Lesser occipital nerve
The triangle represented by a red arrow in the picture above represents the suboccipital triangle.
The contents of the suboccipital triangle are vertebral artery, suboccipital nerve and greater occipital nerve.
The suboccipital triangle is the area in the suboccipital region between the rectus capitis posterior major and the obliquus capitis superior and inferior muscles. It is covered by a layer of dense fibro-fatty tissue, deep to the semispinalis capitis muscle. Its floor is formed by the posterior occipitoatlantal membrane and the posterior arch of the C1 vertebrae.
The suboccipital muscles are:
- Obliquus capitis superior muscle
- Obliquus capitis inferior muscle
- Rectus capitis posterior major muscle
- Rectus capitis posterior minor muscle