1. Surface anatomy of anterior thoracic wall, lung surface marking, pleural reflections
By Amanda tatar

2. Objectives
Explain lymphatic drainage of the breast and its importance in the spread of cancer
Describe the surface markings of the lungs and pleural reflections
Identify important surface landmarks on the anterior thoracic wall
Use the sternal angle (of Louis) to accurately number the ribs on a living subject

3. Anatomy of the breast Both sexes Mammary glands
Suspensory ligaments: attach glands to dermis
15-20 lobules → parenchyma of mammary glands
1 lobule → lactiferous duct → nipple
Lactiferous sinuses – dilated area
Both males and females have breasts, but the mammary glands are more developed in women. In women they are important for lactation and are an accessory gland of the female reproductive system. Male mammary glands are functionless and just a few cords or ducts. Mammary glands attach to the dermis (layer of skin) by suspensory ligaments of Cooper. These are especially well developed in the superior (upper part) breast to support the mammary gland lobules.
15-20 lobules constitute the parenchyma of the mammary glands. Each lobule opens up onto the nipple thorough a lactiferous duct. Every duct has a dilated part just deep (further in) to the areola.
This diagram is showing three different layers/types of breast tissue.
Superiorly (yellow one) it shoes the suspensory ligaments and lobules of fat
Middle it shows the mammary glands in a non-lactating
Inferiorly it shows the mammary glands in a lactating breast

4. Surface anatomy of the breast
Midaxillary line
Ribs 2 → 6
Lateral border of sternum to midaxillary line
Axillary process
2/3 over pectoralis major
1/3 over serratus anterior
Nipple over 4ics = MEN
Axillary process
Transverse = lateral (side) border of the sternum out to the midaxillary line (line down from armpit).
Vertical = Ribs 2 down to 6
The nipple of the breast usually overlies the 4th intercostal space (ics), but in women is much more variable so unreliable as a surface landmark of anatomy
All of the breast overlies fascia of either the pectoralis major muscle (2/3) or the serratus anterior muscle (1/3).
Axillary process/Tail of Spence:
The tissue of the breast may extend out along the border of the pectoralis major muscle in the direction of the axillary fossa (indentation of the armpit). This extension of the breast tissue is called the axillary (armpit) process (extension).
Clinical relevance: pathological breast quadrants

5. Surface anatomy of breast
Intermammary cleft
Body of
sternum
Axillary tail
Anterior
axillary fold
Areola
Nipple
Areolar is pigmented area, altered by hormones after pregnancy
Anterior axillary fold – anterior fold of the axilla area – armpit
Supernumerary nipple = extra nipple to varying degrees of completeness. Occur along two milk lines - line on which nipples may appear – similar to a nipple line of dog or pig
Supernumerary nipple
Xiphoid process

6. Vasculature of breast Arterial supply:
Medial mammary branches of anterior intercostals from internal thoracic arteries
Lateral thoracic from axillary arteries
Thoraco-acromial from axillary arteries
Posterior intercostals from thoracic aorta
Internal thoracic artery branches → medial mammary from anterior intercostals
Axillary artery → lateral thoracic + Thoraco-acromial
Thoracic aorta → posterior intercostals

7. Arterial supply continued
RCC
LCC
AXILLARY
LSC
RSC
In Th
BCA
ARCH
Arch – aortic arch
PIC – posterior interscostals
LCC/RCC – left/right common carotid
BCA – brachiocephalic artery
LSC/RSC – left/right subclavian
AXILLARY – axillary
In Th – Internal Thoracic
AIC – Anterior intercostasl
Med Mam – Median mammary
Tho-Acr – thoraco-acromial
Lat-Tho – Lateral thoracic
AIC
Tho- Acr
PIC
Lat-Tho
Med Mam
HEART

8. Lymphatic drainage of breast
Lymphatics – drainage
All from breast → sub-areolar plexus then:
Axillary: 75 %
Parasternal
Abdominal
Lymphatic system enables drainage of excess tissue fluid, leaked plasma, removal of debris and infection
All lymph from breast goes into the sub-areolar plexus. From here, it then drains into three main types of lymph nodes:
Axillary: 75 %, especially from the lateral breast quadrants
Parasternal or opposite breast
Abdominal (inferior phrenic)
(Axillary drain into the infra or supra clavicular nodes and then into subclavian lymphatic trunk
Parasternal drain into bronchomediastinal trunks)

9. Lymph continued Axillary Nodes: Pectoral Humeral Subscapular Central
Apical
Axillary nodes → supra/infra clavicular → subclavian trunk
Parasternal → bronchomediastinal

10. Importance of lymph Breast carcinoma → metastasis
↑ communication of lymph
Metastasis can be extensive
Left – normal
Right - carcinoma

11. Lung pleurae Visceral – adherent to lungs
Parietal – lines pulmonary cavities
Between = pleural space = serous fluid:
Reduces friction – respiration
Surface tension - cohesion
The pleurae can be imagined with a balloon. Imagine your fist to be a lung. Push your fist into a blown up balloon (until you wrist). The balloon is in contact with your skin (visceral) but also billows out around your fist (parietal). The visceral pleura is attached to the lungs – balloon in contact with your fist. The parietal pleura lines the pulmonary cavities, adhered to the thoracic wall, mediastinum, diaphragm. IN between the pleural layers is the pleural cavity – a potential space (ie not an actual space but where a space can form) in which serous pleural fluid is contained. This is a lubricant, enabling the layers of pleura to slide over one another as needed in respiration. Also provide cohesion like water between glass plates.

12. lungs in prosection Sternum Right lung Left lung VISCERAL PLEURA
Prosection of thorax
External intercostal
muscles
Ribs
Costal margin

13. THORACIC CAVITY IN PROSECTION
Sternum
VISCERAL PLEURA
ON RIGHT LUNG
Prosection of right lung pulled back to see the parietal pleura.
Pleura makes it shiny
PARIETAL PLEURA
(costal)
Costal margin

14. Parietal pleura parts Costal: Mediastinal: Diaphragmatic: Cervical:
Internal thoracic wall surfaces
Endothoracic fascia separates
Mediastinal:
Lateral mediastinum
Diaphragmatic:
Diaphragm
Cervical:
Thorough superior thoracic aperture
2-3cm above clavivles
There are four parts to the parietal pleura:
Costal – covers the internal thoracic wall; ribs, sternum, costal cartilages, intercostal muscles, thoracic vertebrae sides – separated from the wall by endothoracic fascia
Mediastinal – central compartment of thorax; covers lateral sides of it
Diaphragmatic – diaphragm
Cervical – lung extends superior to clavicle, hence parietal pleura does too. This is about 2-3 cm superior to the clavicles

15. Pleural reflections – parietal pleura
Sternal - Anteriorly
Sharp
Costal → mediastinal
Costal - Inferiorly
Costal → diaphragmatic
Vertebral - Posteriorly
Rounder
Abrupt lines where the parietal pleura changes direction from one wall of the pleural cavity to another = pleural reflections

16. Parietal and visceral pleural markings
2cc → 4cc
4cc → 6cc inferiorly (R)
4cc → 6cc curved (L)
6cc → 8cc midaxillary
10 rib posteriorly
PARIETAL:
2cc → 4cc
4cc → 6cc inferiorly (R)
4cc → 6cc curved (L)
6cc → 8cc midclavicular
8cc → 10 rib midaxillary
12 rib posteriorly
EVEN NUMBERS:
Visceral =
Parietal =

17. recesses Pleural cavities not full in expiration → recesses
Costodiaphragmatic
Costomediastinal
Costomediastinal is roughly where cardiac notch is – but not the cardiac notch

18. Surface anatomy – anterior planes
Jugular notch
Sternal angle
Median (midsternal)
Midclavicular - two
MEDIAN LINE
Median – middle
Midclavicular – midpoint of clavicles, parallel to median line
MIDCLAVICULAR
LINES

19. SURFACE ANATOMY – ANTEROLATERAL PLANES
Axillary
fossa
Anterior axillary – along ant. fold (pectoralis major)
Midaxillary – axillary apex ↓
Posterior axillary – along post. fold (latissimus dorsi, teres major)
Anterior
axillary
Midaxillary
Anterior axillary – along anterior axillary fold formed by the border of pectoralis major
Midaxillary – from the axillary apex and down inferiorly, parallel to the anterior axillary
Posterior axillary – posterior axillary fold by latissimus dorsi and teres major, parallel
Pectoralis major, latissimus dorsi and teres major are all thoracic muscles you will learn about 
Posterior
axillary

20. Important features to identify

21. Important levels Jugular notch = T2 Sternal angle Xiphoid process = T9
T4/T5
2cc
Bifurcation of bronchi
Counting ribs from here
Xiphoid process = T9
Level of T4/T5 – very important landmark to know. From there, travel outwards with your fingers to palpate a rib – this is the second rib. Moving your fingers down slowly, you can plapate the ribs numerically

22. Counting the ribs *
Level of T4/T5 – very important landmark to know. From there, travel outwards with your fingers to palpate a rib – this is the second rib. Moving your fingers down slowly, you can plapate the ribs numerically

23. Correspondence! T2
T4/T5 T9

24. CLINICAL RELEVANCE – _?_ thorax!
Accumulation of ‘stuff’ into pleural cavity
Something is broken or torn open
Pneumothorax – air
Hydrothorax – fluid (from effusion)
Hemothorax – blood
Chylothorax - lymph
Build up of fluid etc!

25. quiz
Q. Most of the lymphatic drainage of the breast goes to the other breast? False – most drains to the axillary nodes Q. The parietal pleura crosses the midaxillary line at 8cc? False – crosses the midclavicular line at 8cc, midaxillary at 10cc. Visceral pleura crosses the midaxillary line at 8cc Q. Sternal angle is at the level of T3/T4? False – T4/T5 A B
A = jugular notch aka suprasternal notch
B = midclavicular line – midpoint of clavicle

26. Thank you! mzyart@nottingham.ac.uk In this powerpoint I used:
Point of interest: Pleural effusion – fluid on the lungs
In this powerpoint I used:
Moore and Agur
Teach me anatomy
Acland Anatomy Videos
Google images
Please me any questions or come
ask me at the end!