JOINTS OF NECK Prepared By Dr Sadaf Aziz

JOINTS OF NECK Prepared By: Dr. Sadaf Aziz Teaching Assistant IPMR, KMU

ATLANTO-OCCIPITAL JOINT TYPE: Synovial joint. They are enclosed by a capsule ARTICULAR SURFACES Above: The occipital condyles. These are convex in shape and found on either side of the foramen magnum. Below: the superior articular facets of the atlas. These are concave.

LIGAMENTS 1. THE FIBROUS CAPSULE surrounds the joint. It is thick posterolaterally and thin anteriomedially. 2. ANTERIOR ATLANTO-OCCIPITAL MEMBRANE extends from the anterior margin of foramen magnum above to the upper border of the anterior arch of the atlas below. Laterally it is continuous with the capsular ligament and anteriorly by the anterior longitudinal ligament. 3. POSTERIOR ATLANTO-OCCIPITAL MEMBRANE extends from posterior margin of foramen magnum above to upper border of the posterior arch of the atlas below. Laterally it is continuous with the capsule and inferiolaterally it has a free margin that arches over vertebral artery and 1 st cervical nerve.

• ARTERIAL SUPPLY: vertebral artery • NERVE SUPPLY: first cervical nerve

MOVEMENTS • FLEXION and • EXTENSION (nodding) occur around a transverse axis. • Slight LATERAL FLEXION around anteroposterior axis,

ATLANTO-AXIAL JOINT TYPE: 3 synovial joints ARTICULAR SURFACES: • 2 lateral atlanto-axial joints between the inferior surface of atlas and superior facets of axis. These are plane joints. • A median atlanto-axial joint between the dens and the anterior arch and transverse ligament of atlas. It is a pivot joint.

LIGAMENTS 1. APICAL LIGAMENT connects the apex of odontoid process to the anterior margin of foramen magnum 2. ALAR LIGAMENT lie on each side of the apical ligament and connect odontoid process to medial side of occipital condyles. 3. CRUCIATE LIGAMENT consists of transverse and a vertical part. The transverse part is attached on each side to the inner aspect of the lateral mass of the atlas and binds odontoid process to the anterior arch of atlas. The vertical part runs from posterior part of the body of the axis to the anterior margin of the foramen magnum.

4. MEMBRANE TECTORIA upward continuation of posterior longitudinal ligament. It is attached above to the occipital bone and covers posterior surface of odontoid process and the apical, alar and cruciate ligament. 5. CAPSULE support the joints.

MOVEMENTS • Movements at all joints are rotatory. • The dens forms a pivot around which the atlas rotates ( carrying the skull with it). This movement is limited by the alar ligaments

JOINTS OF VERTEBRAE BELOW THE AXIS • TYPE & ARTICULAR SURFACES: The vertebrae articulate with each other by a cartilaginous joint between their bodies and by synovial joints between their articular processes.

JOINTS BETWEEN 2 VERTEBRAL BODIES • The upper n lower surfaces of vertebral bodies are covered by hyaline cartilage. Sandwiched between the hyaline cartilage is intervertebral disc of fibrocartilage. It strongly unites the bodies of two vertebrae. • In lower cervical small synovial joints are present at the sides of intervertebral disc between the upper and lower surfaces of the bodies of vertebrae.

LIGAMENTS 1. THE ANTERIOR LONGITUDINAL LIGAMENT run as continuous band down the anterior surface of vertebral column from the skull to the sacrum. It is wide and strongly attached to the sides and front of vertebral bodies and intervertebral discs. 2. THE POSTERIOR LONGITUDINAL LIGAMENT run as continuous band down the posterior surface of vertebral column from the skull to the sacrum. It is weak and narrow and attached to posterior borders of the discs. These ligaments hold the vertebrae firmly but at the same time permit a small amount of movement to take place.

JOINTS BETWEEN TWO VERTEBRAL ARCHES • Consists of synovial joints between the superior and inferior articular processes of adjacent vertebrae. • The articular facets are covered with hyaline cartilage and the joints are surrounded by capsular ligament

LIGAMENTS 1. SUPRASPINOUS LIGAMENT runs between the tips of adjacent spines. 2. INTERSPINOUS LIGAMENT run between adjacent transverse process. 3. LIGAMENTUM FLAVUM connects the lamina of adjacent vertebrae. 4. In the cervical region the supraspinous and interspinous ligament are greatly thickened to form the LIGAMENTUM NUCHAE. It extends from the spine of 7 th cervical vertebrae to the occipital protuberence of skull, with its anterior border being strongly attached to the cervical spines in between.

LIGAMENTUM NUCHAE

CLINICAL ANATOMY • Death in execution by hanging is due to the dislocation of the dens following rupture of the transverse ligament of the dens, which then crushes the spinal cord. However, hanging can also cause fracture through the axis or separation of axis from 3 rd cervical vertebrae. • Cervical vertebrae may be fractured or more commonly dislocated by a fall on head with acute flexion of neck.

INTERVERTBRAL DISC • SELF STUDY…. .