“Topography of the Thorax: The Thoracic Wall” Excerpt From: Imperial College London. “MBBS Year 1 Anatomy of the Thorax Spring Term Course Guide 2017/18”. Apple Books. Flashcards
What is the vertebral level of the sternal notch
T2
Vertebral level off the manubrium
T2-T4
Vertebral level of the sternal angle
T4/T5
Vertebral level of the sternal body
T5-T8
Vertebral level of the diploid process
T9
What is the vertebrae prominens
The spinous process of C7 (which overlies the vertebral body of T1)- most prominent in the lower neck
When the patient bends you can see this
What guidance is used for aspiration and injection into the sternoclavicular joint
Although the sternoclavicular joint is easily palpable and accessible, CT guidance is used during aspiration and injection to prevent entry into the superior mediastinum and damage to pleura and great vessels
How can we facilitate radiographic identification of ribs
Knowledge of rib angulation aids radiographic identification, for example the posterior part of the rib appears to curve inferolaterally and is the most visible part.
The angle of the rib is palpated posteriorly, a few centimetres lateral to the vertebral spinous processes.
What is the angle of the rib a useful marker for
The angle is a useful marker for the lateral cutaneous nerves and vessels, which emerge just lateral to it and can be anaesthised in this region.
How can ribs be palpated
Ribs 4-10 can be palpated in the midaxillary line starting with rib 4 at the skin of the axillary floor. Rib 10 is continuous with the costal margin.
The free lateral ends of ribs 11 and 12, can be palpated posteriorly in lean individuals and can be traced medially to help identify the T11 and T12 vertebrae.
What is meant by the costal margin
This refers to the free inferior border of the anterior and lateral thoracic cage formed by the distal ends of the costal cartillages 7-10. It can be palpated inferolaterally from the xiphisternum to rib 10 and is a useful landmark.
Describe the costal cartillages
These connect the distal parts of ribs 1-10 to the sternum or adjacent costal cartilage. In lean individuals the cartillage of ribs 1-7 vertebrosternal can be identified at the sternum and serve as useful markers of underlying structures.
The cartillages pass medially, or superomedially, to the sternum and can be identified on radiographs by their direction of travel and relative radiolucency
Structure of a typical ribs
see diagram!
Structure of atypical ribs
see diagrams!
Structure of thoracic vertebrae
see diagram!
What structures pass through the intervertebral foramen
Spinal nerve and blood vessels
Each spinal nerve exits the vertebral canal laterally through an intervertebral foramen. The foramen is formed between adjacent vertebral arches and is closely related to intervertebral joints.
Describe the structure of the intervertebral foramen
The superior and inferior margins are formed by notices in adjacent pedicles.
The posterior margin is formed by the articular processes of the vertebral arches and the associated joint (zygapophysial joint).
The anterior border is formed by the intervertebral disc between the vertebral bodies of adjacent vertebrae.
Summarise the types of joints that exist between vertebrae
symphyses between vertebral bodies
synovial joints between articular processes
A typical vertebrae has a total of six joints with adjacent vertebrae: four synovial joints (two above and two below) and two symphyses (one above and one below). Each symphyses includes an intervertebral disc.
Describe the symphyses joints
The symphysis joints between adjacent vertebral bodies is formed by a layer of hyaline cartilage on each vertebral body and an intervertebral disc, which lies between the layers.
Describe the movement that these symphyses joints allow for
An amphiarthrosis is a joint that has limited mobility. An example of this type of joint is the cartilaginous joint that unites the bodies of adjacent vertebrae. Filling the gap between the vertebrae is a thick pad of fibrocartilage called an intervertebral disc (Figure 2). Each intervertebral disc strongly unites the vertebrae but still allows for a limited amount of movement between them. However, the small movements available between adjacent vertebrae can sum together along the length of the vertebral column to provide for large ranges of body movements.
The annulus fibrosis limits rotation between vertebrae.
Describe the joints between vertebral arches (zygapophysial joints)
the synovial joints between superior and inferior articular processes on adjacent vertebrae are the zygapophysial joints. A thin articular capsule attached to the margins of the articular facets encloses the joints.
What type of movements do the zygapophysial joints allow
In cervical regions, the zygapophysial joints slope inferiorly from anterior to posterior. This orientation facilitates flexion and extension.
In thoracic regions, the joints are orientated vertically and limit flexion and extension, but facilitate rotation.
In lumbar regions, the joint surfaces are curved and adjacent processes are interlocked, thereby limiting range of movement, though flexion and extension are still. major movements in the lumbar region
Describe the joints between spinous processes
Interspinous and supraspinous – join the spinous processes of adjacent vertebrae. The interspinous ligaments attach between processes, and the supraspinous ligaments attach to the tips.
These are ligaments
What types of movement do the joints between spinous processes allow for
Allow for gliding movements between vertebrae These serve to resist excess forward or backward bending movements of the vertebral column, respectively.
