Vertebrae and Trunk Overview

Typical Vertebrae

• The body is responsible for weight bearing
• The vertebral arch consists of pedicles and laminae
• The vertebral foramen is the opening created by the arch and body
• There are seven processes: two transverse, one spinous, and four articular
• Vertebral notches are indentations on the superior and inferior aspects of the pedicles

Cervical Vertebrae

• There are seven cervical vertebrae located between the thorax and skull
• Cervical vertebrae are generally smaller in size compared to others
• They have a foramen within each transverse process
• C1 refers to the Atlas
• C2 refers to the Axis
• C3-T1 have an uncal/uncinate process
• Uncal/uncinate processes are hook-shaped and prevent posterior linear translation movements
• They also limit lateral flexion

Overview of the Trunk

• The trunk is the "core" of the body
• It consists of the thorax (chest), abdomen and back

Trunk Skeletal Structure

• Vertebral column includes 7 cervical, 12 thoracic, and 5 lumbar vertebrae plus 1 fused sacral and 1 fused coccygeal bone
• The thoracic cage consists of the sternum and ribs
• The pelvic girdle (upper part) includes the Ilium, Pubis and Ischium

Trunk Functions

• Provides support and protection
• Offers attachments for a complex network of muscles
• Facilitates movement through extrinsic and intrinsic muscle groups
• Extrinsic muscles move the upper limbs & the ribs
• Intrinsic muscles maintain posture & moves the vertebral column

Arthrology and Joints

• Atlanto-Occipital & Atlanto-Axial Joints allow for head/neck Flexion & Extension
• Atlanto-Axial Joint Allows head/neck Rotation

Thoracic Vertebrae

• Twelve thoracic vertebrae articulate with the ribs and have long processes

Lumbar Vertebrae

• Five lumbar vertebrae provide skeletal support for the posterior abdominal wall
• They are characterized by their large size

Sacrum and Coccyx

• The sacrum consists of five fused sacral vertebrae and makes up a component of the pelvic wall
• The coccyx consists of four fused vertebrae forming a small triangular bone

Trunk: Thoracic & Ribs Articulation

• Includes the vertebra that is connected to the ribs

Intervertebral Foramina

• Formed on each side between adjacent parts of vertebrae and their discs
• Allows spinal nerves and blood vessels to pass in and out of the vertebral canal
• It's a confined space surrounded by bone, ligaments, and joints
• Pathology in these structures and muscles can affect structures within the foramen

Posterior Spaces

• Lie between the vertebral arches, specifically between the laminae and spinous processes of vertebrae

Joints Between Vertebrae

• There are two major types: symphyses and synovial between articular processes
• A typical vertebra has six joints: two symphyses (one above and one below) and four synovial (two above and two below)
• Symphyses joints are located between vertebral bodies and intervertebral discs

Anulus Fibrosus

• It consists of an outer ring of collagen surrounding a wider zone of fibrocartilage in a lamellar configuration. This arrangement limits rotation between vertebrae

Nucleus Pulposus

• It fills the center of the intervertebral disc, is gelatinous, and absorbs compression forces between vertebrae. It also maintains a gap between vertebrae to allow space for nerves.

Zygapophysial Joints

• They are synovial joints between the superior and inferior articular processes on adjacent vertebrae

Uncovertebral Joints

• Located between the uncinate process and the body of the vertebra above

Trunk: Vertebral Column Ligaments

• The supraspinous ligament and ligamentum nuchae connect and pass along the tips of the spinous processes from C2 to the sacrum
• Interspinous ligaments pass between adjacent vertebral spinous processes
• Anterior and posterior longitudinal ligaments are on the anterior and posterior surfaces of the vertebral bodies
• Ligamenta flava pass between the laminae of adjacent vertebrae

Trunk: Vertebral Column Curves

• The vertebral column has cervical, thoracic, lumbar, and sacral curves.
• These curves are important for weight bearing and maintaining normal posture.

Trunk: Vertebral Column Deviations

• Kyphosis is an exaggeration of the thoracic curve
• Lordosis is an exaggeration of the lumbar curve
• Scoliosis is a lateral curvature of the spine

Trunk: Vertebral Column Movement

• The trunk allows for flexion, extension, lateral flexion (right and left). The rotation can happen to both sides
• The most movable vertebrae generally exist where one vertebral segment begins or ends

An overview of the trunk as the body's core structure, with a focus on typical and cervical vertebrae. Key features such as the vertebral arch, foramen, and processes are described. Special attention is given to cervical vertebrae, including the Atlas, Axis, and uncal processes.