1. WELCOME TO SCRUBS ANATOMY TEACHING
@SCRUBSNotts
scrubsnottingham
Nottingham SCRUBS Student Surgical Society

2. Surface Anatomy of Thorax
Anna Kober
Play as slideshow to see animations

3. Learning Objectives
Surface anatomy of anterior thoracic wall, lung surface marking, pleural reflections (include planes and spinal levels)
Identify important surface landmarks on the anterior thoracic wall and use the sternal angle (of Louis) to accurately number the ribs on a living subject
Surface anatomy and lymphatic drainage of the breast

4. Surface Anatomy of Thorax

5. Lines and Planes 1 x anterior midsternal line 2 x midclavicular lines
Median place
Divides sternum down the middle in half
2 x midclavicular lines
Pass through midpoints of clavicles
Clavicle is the anatomical term for collarbone

6. Lines and Planes Anterior axillary line Midaxillary line
Runs along anterior axillary fold
Midaxillary line
Runs between the anterior and posterior lines
Runs from the apex (deepest part) of the axilla
Posterior axillary line
Runs along posterior axillary fold
Axilla is the anatomical term for armpit
Anterior fold is formed by the border of the pectoralis major as it spans from the thorax to the humerus
Posterior fold is formed by the latissimus dorsi and teres major muscles as they span from the back to the attach to the humerus

7. Important Surface Landmarks

8. Bony Surface Landmarks
Jugular notch
Part of manubrium of sternum
Between 2 heads of SCM
Clavicle
Articulates with sternum and scapula
Sternum
Ribs
Costal margin
Inferior border of ribcage
Jugular notch
sternum
SCM - sternocleidomastoid

9. Surface Landmarks: Muscles
Pectoralis major
Serratus anterior
(sternocleidomastoid, trapezius, deltoid)

10. Sternal Angle On yourself palpate the jugular notch
Move your finger down…
RIDGE

11. Sternal Angle Sternal angle = manubriosternal joint = angle of Louis
Manubrium -> body
Articulation for costal cartilage of rib 2
Level of T4 and T5 vertebrae -> T4/T5 plane

12. T4-T5 plane Transverse plane
Plane cuts through -> IV disc between T4 and T5 + sternal angle + costal cartilage of rib 2
A lot of things happen at the level of this plane…
Division of mediastinum into superior and inferior
Bifurcation of trachea
Ascending aorta -> arch of aorta
Trachea bifurcates into right and left main bronchi

13. Counting Ribs Jugular notch Move down to palpate sternal angle
Articulation point for costal cartilage of rib 2
Move laterally -> palpate rib 2
Move inferiorly -> second intercostal space
Keep moving down + count the ribs!
Palpate = feel

14. Clinical Significance
Chest X-rays (CXR)
Surface markings and anatomical relations

16. Lungs and Pleura

17. Lungs and Pleura
2 lungs and 5 lobes (3 on the right and 2 on the left)
Wrapped in pleura
Visceral pleura – adhered to lung
Parietal pleura -> adhered to thoracic wall, mediastinum and diaphragm + lines pulmonary cavities
Pleural cavity -> potential space in between the two layers
Analogy:
Hand = lung
Balloon = pleura
Visceral pleura -> part of balloon that is in contact with skin
Parietal pleura -> the remaining surfaces of the balloon

18. Parietal Pleura Remember this is in 3D and not flat lines Costal
Surface of lung facing ribcage
Mediastinal
Surface facing mediastinum
Diaphragmatic
Surface facing diaphragm
Cervical
Extends through the superior thoracic aperture into the root of the neck
Forms cup-shaped dome over apex of lung

19. Pleural Reflections
Reflection = parietal pleura changes direction from one wall of pleural cavity to another
Sternal reflection = costal pleura <-> mediastinal pleura anteriorly
Costal reflection = costal pleura <-> diaphragmatic pleura
Vertebral pleura = costal pleura <-> mediastinal pleura posteriorly

20. Lung Surface Markings Tracing the outline of the lungs
Parietal pleura extends approximately 2 ribs inferior to lung

21. 2nd cc 4th cc 6th cc Midclavicular line at level of 8th cc Midaxillary line at level of 10th rib Scapular line at level of 12th rib Spinous process of T12
Trace inferiorly
L trace laterally + inferiorly to form cardiac notch
R trace inferiorly
Trace inferiorly + laterally
Trace inferiorly + laterally
Trace inferiorly + medially (now posterior)
Trace medially

22. Lung fissures Oblique fissure Horizontal fissure (right lung only)
Spinous process of T2 posteriorly -> 6th costal cartilage anteriorly
Horizontal fissure (right lung only)
From oblique fissure along rib 4 to 4th costal cartilage anteriorly
R lung = oblique + horizontal fissure = 3 lobes
L lung = oblique fissure = 2 lobes

23. Lung Recesses
Lungs do not completely occupy pleural cavity -> this gives rise to recesses
Costomediastinal recess
Particularly on the left in relation to the heart bulge
Costodiaphragmatic recess
Between lower lung margin and lower margin of pleural cavity

24. Clinical Significance: Auscultation sites

25. Surface Anatomy and Lymphatic Drainage of Breast

26. Breast Vary in size Typically ribs 2-6
Overlie pectoralis major + serratus anterior
4 quadrants
Upper outer and inner
Lower outer and inner
Axillary tail/axillary process/ tail of Spence
Extension of mammary gland superolaterally around lower margin of pectoralis major to enter axilla
/ axillary process/ axillary tail

27. Breast Body of sternum – T4/5 -> T9 Xiphoid process – T9
Nipple – mainly smooth muscle fibres
Areolae – pigmented and contains sebaceous glands
In men: nipple overlies 4th intercostal space 10cm from anterior midsternal line
In women: location is variable
Sebaceous glands enlarge during pregnancy and secrete oily substance which acts as protective lubricant over nipple

28. Structure
Breast contains lobules each drained by a lactiferous duct into the nipple

29. Lymphatic Drainage
>75% lymph (particularly from lateral quadrants) -> axillary lymph nodes
Medial quadrants -> parasternal lymph nodes
Sentinel Lymph node
Biopsied to determine spread of cancer as other lymph nodes drain to it

30. QUIZ A Q) What is A? Q) It is a feature of which bone? - Jugular notch
- Manubrium part of the sternum

31. QUIZ B Q) What is B? Q) What are the surface landmarks of B?
- Oblique fissure
Q) What are the surface landmarks of B? B
- Extends from spinous process of T12 to 6th costal cartilage anteriorly

32. Thank you! Any questions? References: @SCRUBSNotts scrubsnottingham
Moore and Agur
Gray’s Anatomy for Students
Teach me anatomy
Google Images
@SCRUBSNotts
scrubsnottingham
Nottingham SCRUBS Student Surgical Society
Any questions?