SUBOCCIPITAL TRIANGLE

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SUBOCCIPITAL TRIANGLE
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Bony Articulations

• Occipital bone
• Occipital condyles.
• Atlas
• Posterior tubercle.
• Posterior arch.
• Anterior arch.
• Transverse process with foramina.
• Lateral masses
• Articulation with occipital condyles.
• Articulation with axis.

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Bony Articulations

• Axis
• Dens (odontoid process).
• Spinous process.
• Transverse processes with foramina.

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Vertebral Column Ligaments

• Anterior longitudinal ligament.
• Posterior longitudinal ligament.
• Ligamentum flavum.
• Ligamentum nuchae
• Supraspinous interspinous ligaments.

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Cervical and Craniovertebral Joints

• Three synovial joints
• No intervertebral disc.
• Between dens and anterior arch of the atlas.
• Between lateral masses of atlas and axis (x2).
• Ligaments
• Apical ligament.
• Alar ligaments.
• Cruciate ligaments.
• Tectorial membrane.

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Suboccipital Triangle Muscles

• Obliquus capitis superior
• Weak extensor of the neck.
• Obliquus capitis inferior
• Strong rotator of atlas.
• Rectus capitis posterior major
• Extension of vertebral column.
• Rectus capitis posterior minor
• Extension of vertebral column.

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Floor and Roof

• Floor
• Posterior atlanto-occipital membrane.
• Roof
• Semispinalis capitis muscle.

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Suboccipital Triangle Contents

• Suboccipital nerve
• Dorsal ramus of C1.
• No sensory function and no dorsal root.
• Motor to muscles of suboccipital triangle.
• Greater occipital nerve
• Dorsal ramus of C2.
• Sensory to back of skull.

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Suboccipital Triangle Contents

• Third occipital nerve
• Dorsal ramus of C3.
• Vertebral artery.