DE LA SALLE HEALTH SCIENCES INSTITUTECollege of Medicine

Rocel Christine D. PugayFirst Year Section B

TOPIC: Thoracic Wall

Illustrate and/or explain the following topics and submit typewritten output

I. STERNUM

A. Pectus Carinatum

Pectus carinatum is a breastbone (sternum) and rib cartilage deformity that causes the chest to bow outward. It is caused by a defect in the tough connective tissue (cartilage) that holds the ribs to the breastbone. It is sometimes called “pigeon chest” because the chest can look like a bird’s breast. Pectus carinatum symptoms can include pain. The opposite condition, called pectus excavatum, makes the cartilage grow inward. Figure 1. Pectus Carinatum Radiograph

Source: radiopaedia.org

B. Pectus Excavatum

Pectus excavatum is a condition in which a person's breastbone is sunken into his or her chest. In severe cases, pectus excavatum can look as if the center of the chest has been scooped out, leaving a deep dent.

Figure 2. pectus ExcavatumSource: en.wikipedia.org

C. Sternoschisis

Sternoschisis also known as or related to bipartite sternum, sternum bifidum, sternal cleft, cleft sternum, bifid sternum. A developmental defect characterized by a longitudinal fissure in the sternum due to incomplete fusion of the cartilaginous sternal bars.

Figure 3. SternoschisisSource: www.google.com

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II. RIBS

A. Surface Anatomy. Check for Intercostal spaces and explain their clinical significance

The intercostal space is traversed during surgical procedures like pleural taps. When a chest drain is being inserted, it should be important to avoid the location of the neurovascular bundle by inserting the needle just above the rib at either the 4th, 5th or 6th intercostal spaces. Figure 4. Surface Anatomy of Ribs

Source: Netter’s Clinical Anatomy

B. Cervical Ribs. Correlate with Thoracic Outlet syndrome

Thoracic outlet is the space between your collarbone (clavicle) and your first rib. This narrow passageway is crowded with blood vessels, muscles, and nerves. If the shoulder muscles in your chest are not strong enough to hold the collarbone in place, it can slip down and

Figure 5. Thoracic Outlet Syndrome forward, putting pressure on the nerves Source: http://orthoinfo.aaos.org/ and blood vessels that lie under it. This causes a variety of symptoms which together are known as thoracic outlet syndrome.

Thoracic outlet syndrome can result from injury, disease, or a congenital problem, such as an abnormal first rib. It is more common in women than in men, and poor posture and obesity can aggravate the condition.

C. Lumbar Ribs. Clinical Significance

Lumbar rib is a very rare anomaly of the ribs characterized by an extra rib arising from lumbar vertebrae. Extra rib/ supra rudimentary ribs when present usually arise from cervical vertebrae, although sacral, coccygeal and intrathoracic ribs have also been reported.Lumbar ribs arising from vertebrae may be mistaken for kissing osteophytes, transverse process anomalies or abdominal vessel anomalies.

Figure 15. Lumbar RibsSource: www.google.com.ph

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D. Explain “flail chest.”

A flail chest occurs when a segment of the thoracic cage is separated from the rest of the chest wall. This is usually defined as at least two fractures per rib (producing a free segment), in at least two ribs. A segment of the chest wall that is flail is unable to contribute to lung expansion. Large flail segments will involve a much greater proportion

Figure 16. Flial chest of the chest wall and may extend bilaterally or involve the Source: http://www.trauma.org/ sternum. In these cases the disruption of normal pulmonary mechanics may be large enough to require mechanical ventilation.

The main significance of a flail chest however is that it indicates the presence of an underlying pulmonary contusion. In most cases it is the severity and extent of the lung injury that determines the clinical course and requirement for mechanical ventilation. Thus the management of flail chest consists of standard management of the rib fractures and of the pulmonay contusions underneath.

E. Discuss difference between “pump handle” movement versus “bucket handle” movement of chest excursions.

PUMP HANDLE BUCKET HANDLEmovement of ribs

results in change in anteroposterior diameter of the thorax

results in change in transverse diameter of the thorax.

change in volume of thorax that helps inspiration and expirationanterior end of the rib is lower than the posterior end

during elevation of the rib, the anterior end also moves forwards

middle part of rib is lower than anterior and posterior ends

Movement at costovertebral joints 2 to 6 about a side-to-side axis results in raising and lowering the sternal end of the rib, the "pump-handle" movement.

Movement at costovertebral joints 7 to 10 about an anteroposterior axis results in raising and lowering the middle of the rib, the Bucket-handle movement.

Figure 17. Pump and Bucket Handle Movement of the ribsSource: www.google.com.ph

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III. ILLUSTRATE THE FOLLOWING ANATOMICAL LANDMARKS IN SURFACE ANATOMY

A. Jugular NotchB. Midsternal lineC. Calivular notchD. Parasternal lineE. Sternal Angle(of louise)F. Midclavicular line

G. Xiphoid ProcessH. Anterior Axillary lineI. Costal angleJ. Midaxillary lineK. Costal MarginL. Posterior axillary line

Figure 18. Surface Anatomy of ThoraxSource: www.google.com

Sources:

Seattle Children’s Hospital Official Website, ‘Pectus Carinatum’, retrieved last September 1, 2015, from http://www.seattlechildrens.org/medical-conditions/bone-joint-muscle-conditions/pectus-carinatum/

Mayo Clinic Official Website, ‘Pectus Excavatum’, retrieved last September 1, 2015, from http://www.mayoclinic.org/diseases-conditions/pectus-excavatum/basics/definition/con-20028599

Radiopedia.org Official Website, ‘Lumbar Rib’, retrieved last September 2, 2015, from http://radiopaedia.org/articles/lumbar-rib

Trauma.org Official Website, ‘Chest Trauma: Rib Fractures and Flial Chest’, retrieved last September 2, 2015, from http://www.trauma.org/archive/thoracic/CHESTflail.html

Ortho Info: American Academy of Orthopaedic Surgeon Official Website, ‘Thoracic Outlet Syndrome’, retrieved last September 2, 2015, from http://orthoinfo.aaos.org /topic.cfm?topic=a00336

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