surface anatomy
DESCRIPTION
surface anatomyTRANSCRIPT
PC 824 Surface Anatomy
6.0 A A
Alexa Doig
Sunday 5/17 9:00 AM - 5/17 4:30 PM
Surface Anatomy Alexa Doig Level: Beginner Content Description Surface anatomy is the study of topographical relationships between palpable and nonpalpable anatomical structures and involves the mapping of deep organs to the body surface. This session will begin with a review of cervical, thoracic, and abdominal anatomy, emphasizing the relationships between internal organs and palpable landmarks on the axial skeleton. The rest of the session will consist of a hands-on workshop where participants will explore the relationships between the visceral organs, blood vessels, and nerves, and the palpable skeletal landmarks that create the surface map. understand the relationships between key organs and their associated vertebral levels, and apply this knowledge to assessment, diagnosis, and situations requiring the accomplishment of procedural tasks. Learning Outcomes At the end of this session the attendee will be able to: 1. Identify the relationships between palpable osteological landmarks of the axial skeleton and key vertebral levels 2. Identify relationships between palpable osteological landmarks and key levels of the vertebral column 3. Create a map on the surface of the body by identifying palpable osteological landmarks that outline the visceral organs, vessels and nerves of the neck, thorax and abdomen Summary of Key Points 1. Review of palpable osteological landmarks of the:
a. Sternum b. Ribs c. Vertebral column d. Pelvis (os coxa)
2. Map the location and pathways of visceral organs, vessels and nerves of the neck including:
a. Location of the esophagus and trachea b. Pathways of the vagus and phrenic nerves in the neck c. Pathways of key arteries and veins of the neck d. Identify clinical applications of cervical surface anatomy
3. Create a map on the surface of the body by identifying palpable osteological landmarks that outline the
visceral organs, vessels and nerves of the thorax including: a. Location of heart and great vessels in the mediastinum b. Location of the heart valves and the locations for optimal auscultation c. Pleural sacs and lungs with particular attention to the thoracic inlet, cardiac notch, and pleural
recesses d. Other structures in the mediastinum such as the esophagus and conducting airways of the respiratory
system e. Pathways of the vagus and phrenic nerves in the thorax f. Identify clinical applications of thoracic surface anatomy
4. Create a map on the surface of the body by identifying palpable osteological landmarks that outline the
diaphragm, visceral organs, vessels and nerves of the abdomen including: a. Anterior profile of the diaphragm
i. Changes in the diaphragm profile with diaphragmatic excursion b. Anterior and posterior profiles of the liver 2
c. Location of the gall bladder d. Location of the stomach, intestines, spleen, and pancreas, with attention to the peritoneal or
retroperitoneal location of each organ e. Location of the kidneys in the retroperitoneal abdomen f. Pathway of the abdominal aorta and all of its visceral branches g. Identify clinical applications of abdominal surface anatomy
Bibliography/Webliography Lumley, JS. Surface Anatomy: The Anatomical Basis of Clinical Examination. 3rd ed. London, England: Churchill Livingstone; 2001. Standring, S., ed. Gray’s Anatomy: The Anatomical Basis of Clinical Practice. 39th ed. Philedelphia, PA: Elsevier Churchill Livingstone; 2005. Tixa, S. Atlas of Palpatory Surface Anatomy of Limbs and Trunk. Teterboro, NJ: Icon Learning Systems, LLC; 2003
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Surface AnatomyAlexa Doig RN, PhDUniversity of UtahCollege of Nursing
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Copyright © 2001 by Mark Nielsen
All rights reserved. No part of this book may be reproduced in any form what-soever, by photograph or xerography or by any other means, by broadcast or transmission, by translation into any kind of language, nor by recording elec-
tronically or otherwise, without permission in writing from the author.
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Course Manual for
Surface Anatomy
Alexa DoigCollege of NursingUniversity of Utah
Mark NielsenDepartment of Biology
University of Utah
Artwork by Jamey Garbett
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PrefaceWhen we think about anatomy the mind conjures up mental images of cadavers dis-sected to show the deeper structures of the body such as muscles, vessels, and vis-cera. These mental images arise as a result of the way we approach anatomical learn-ing. In order to gain a knowledge of anatomy we first remove the skin. As we delve deeper into the layers of the body, only then do we see and learn the relationships of anatomical structure. For to really comprehend the body, like any natural wonder, it must be explored. To maximize the learning experience there are many tools avail-able to the anatomical explorer. There are books filled with descriptive text. There are books filled with photographs and illustrations. There are computer programs. While all of these are valuable supplements that streamline the exploration process, it is impos-sible to gain a true understanding without taking this complex natural wonder apart. It could be said that to study anatomy without books is to explore the Grand Canyon without a map, while to study anatomy with only books is not to go to the Grand Can-yon at all.
While cadaveric studies are critical for a true understanding of the subject, we often forget the real world application of anatomy. In most professions that use a knowledge of anatomy as a tool of their trade that tool, anatomical knowledge, is applied to liv-ing, breathing, dynamic bodies. It is not always a viable option to take this living form apart to find a solution or analyze a problem. For this reason, it is important to have a strong understanding of surface anatomy. Surface anatomy is the knowledge base that allows one to map deep structures onto the surface of the body. In the various health professions this can be one of the most valuable tools in the anatomy tool box.
In order to bring anatomy to the surface it is important to make use of identifiable sur-face landmarks. Many deep structures of the body, that are impossible to see or feel, can be related to surface structures through a clear knowledge of their topographical relations. With this knowledge one can use techniques such as palpation, percussion and auscultation to evaluate internal conditions.
The intent of this course is to provide you with a better knowledge of how the deep topography of the body relates to what you can see and feel on the surface. This manual will outline some of the important topographical aspects of deep body anatomy and will map this anatomy to key surface landmarks.
Mark NielsenUniversity of Utah
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Surface Anatomy
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Suprasternal (jugular) notch
This is the notch at the superior end of the sternum. It is easily palpated between the two sternal ends of the clavicle.
A horizontal line transecting the floor of the notch corresponds to the bottom edge of the second thoracic vertebra or the disc between T2 and T3.
Skeletal Landmarks of the Thorax and AbdomenSternumThis is a relatively subcutaneous bone that is easily palpated throughout its length. Place your fingers in the intercostal spaces to either side of the sternum and palpate the lateral edges of the bone. This is a relatively narrow bone.
Suprasternal notch
Sternal angle
Costal cartilage of 2nd rib
Sternal angle (manubriosternal joint)
Approximately 5 cm (2.5 inches) below the suprasternal notch palpate a transverse ridge on the anterior surface of the sternum. This ridge, the sternal angle, is the junction of the manubrium and body of the sternum.
If you move your fingers directly laterally along this ridge you will move onto the costal cartilage of the second rib. This is a very constant relationship.
On some individuals it can be difficult to palpate the sternal angle. Using the tips of your fingers and a little pressure, rub your fingers up and down on the sternum until you find it. Confirm your find by the relation to the second rib.
A horizontal line transecting the sternal angle corresponds to the disc between vertebrae T4 and T5 or the top edge of fifth thoracic vertebra.
Body
Manubrium
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Sternum (continued)
Xiphisternal joint
As you continue to palpate down the anterior surface of the sternum you will feel a ridge or depression as your fingers reach the inferior end of the sternal body. This can vary considerably from person to person. This marks the point of union between the sternal body and xiphoid process.
Carefully, as this can be a tender region, feel for the xiphoid process. In some individuals it will bend inward and be less obvious, while in others it will stand out and be easily palpated.
Notice that the costal cartilage of the seventh rib articulates at this point. This is the last rib to articulate directly with the sternum. A horizontal line transecting this joint corresponds to the disc between vertebrae T9 and T10.
Xiphisternal joint
Costal cartilage of 7th ribXiphoid process
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Surface Anatomy
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RibsAs you palpate the ribs you quickly notice that they are most easily palpated from anterolateral to posterolateral. Anteriorly, they can be difficult to palpate because of the potentially thick pectoralis musculature and the mammae in the female. Posteriorly as they approach the vertebrae, they are under the cover of the erector spinae musculature. If the pectoralis major is not to thick, the costal cartilages are easy to palpate at the their sternal ends.
On the lateral side of the thorax palpate the intercostal spaces between a series of ribs. Notice that the ribs and their spaces are directed obliquely anteriorly and inferiorly, with the obliquity increasing from the top of the rib cage toward the bottom. Because of this, the intercostal space is wider anteriorly than it is posteriorly.
Costal cartilages
As you palpate each of the first seven ribs you will notice that their anterior ends are joined directly to the sternum by their costal cartilages. This fact leads to their designation as the true ribs. The costal cartilages of ribs 8, 9, and 10, the so-called false ribs, do not attach directly to the sternum, instead they attach to the costal cartilage of the next superior rib. The costal cartilage of rib eight attaches to the costal cartilage of rib seven, the costal cartilage of rib nine attaches to the cartilage of rib eight, and likewise for rib ten.
Verify this by palpating the rib interspace above ribs 8, 9, and 10. Notice that as you move towards the sternum in this interspace that your palpating fingertips reach a dead end to the interspace where the lower costal cartilage joins the costal cartilage of the rib above it. The costal cartilages of ribs 7, 8, 9, and 10 then form the inferior costal margin of the anterior rib cage. Ribs 11 and 12, the floating ribs, have small cartilaginous tips but do not join to the other ribs. This can also be the case with tenth rib which is sometimes floating or weakly attached to the rib above.
Costal cartilage of 4th rib
Costal cartilage of 8th rib
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Ribs (continued)
Angle of ribs
As you palpate the ribs posteriorly notice that three to four finger-breadths from the spinous processes of the thoracic vertebrae the ribs become covered by the thick muscles of the vertebral column. This dorsal palpable region of the rib is called the angle.
It can be difficult to palpate the angle of the upper four or five ribs because of the scapular musculature. Because of this angle formed by the rib, the vertebral end of the rib is deeply situated to the muscles of the back and vertebral processes, rendering it impalpable.
Angle of 9th rib
Angle of 9th rib
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Surface Anatomy
Ribs (continued)
Rib 1
You will find it difficult to palpate much, if any, of the first rib as it lies under the cover of the clavicle. With a little pressure you can palpate its costal cartilage just inferior to the sternal end of the clavicle.
Rib 2
This rib is palpable as the first evident rib of the superior thorax. It is easily confirmed because of its relation to the sternal angle. Verify that you are palpating the second rib by moving your fingers onto the scapula and feeling the sternal angle. The converse of this is also true. Verify that you have located the sternal angle by moving laterally onto the second rib.
Ribs 3 to 6
The ease with which you are able to palpate these ribs anteriorly will vary from subject to subject depending on the development of the pectoralis major muscle and the mammary anatomy of the female. Try to find each rib in succession just lateral to the sternum by sliding your fingers off the rib above into the interspace and then onto the next rib.
Rib 7
The seventh rib is the rib whose costal cartilage joins the sternum at the junction of the body and xiphoid process. Be careful in this identification because the costal cartilage of the seventh rib often fuses with the costal cartilage of the sixth rib above it presenting a wide span of costal cartilage near the sternum. The seventh costal cartilage is the bottom edge of this span of cartilage adjoining at the xiphisternal junction.
TT
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Ribs (continued)
Ribs 8 and 9
Ribs eight and nine are the first ribs whose costal cartilage does not reach the sternum. Verify this fact by palpating the rib interspace superior to each of these ribs until you find it reach a dead end before reaching the sternum.
To gain a sense for the degree of obliquity in the middle ribs trace the eighth rib from posterior to anterior noting the following points. Posteriorly the eighth rib joins the vertebral column between the seventh and eighth vertebrae. Find the angle of the eighth rib and make a mark. This should be just slightly below the inferior angle of the scapula. Place a piece of string at this point and run it around to the front of the body in a horizontal plane. Notice that the string crosses the fifth costal cartilage where it joins the sternum.
As you trace the rib anteriorly stop when you reach the mid-clavicular line (a vertical line that divides the clavicle in half, this line should be on the lateral side of the nipple in the male, this can vary in the female) as this represents the point where the eighth rib joins its costal cartilage. Notice how far inferior this point is from the fourth costal cartilage. A horizontal line through this point corresponds to the level of the bottom of thoracic vertebra 12. The ribs than span four to five vertebrae in their course from posterior to anterior.
Costal cartilage of 9th rib
Costal cartilage of 8th rib 8th rib
9th rib
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Surface Anatomy
Ribs (continued)
Rib 10
The costal cartilage of rib ten, like those of ribs eight and nine, joins the costal cartilage of the rib superior to it. This can be verified in a similar fashion to ribs eight and nine above. Sometimes the costal cartilage of the tenth rib does not join the cartilage of the rib superior to it. When this occurs it can be classified as a floating rib, like ribs eleven and twelve.
Ribs 11 and 12
The small cartilage tips of ribs 11 and 12 do not join the costal cartilage of superior ribs. Because of this, they are often referred to as floating ribs. The twelfth rib can be extremely variable. Sometimes it can be so small that it becomes difficult to palpate at all. If this is suspected you can verify it by counting the ribs from superior to inferior. Notice how close the twelfth rib is to the iliac crest.
12th rib
11th ribIliac crest
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Surface Anatomy
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Ribs (continued)
Costal margin
The costal margin is the cartilaginous and bony margin defining the bottom of the rib cage. Anteriorly the seventh costal cartilage defines it near the sternal border. Moving laterally it is defined by the cartilages of the eighth, ninth, and tenth costal cartilages. Further laterally and posteriorly it is defined by the eleventh and twelfth ribs. Palpate this margin by running your fingers from the xiphisternal junction along the bottom edge of the costal cartilages of ribs 7, 8, 9, and 10 back to the angle of rib twelve.
Costovertebral angle
Between the 12th rib and the lumbar vertebral column is a triangular space called the costovertbral angle (CVA). Find this space by palpating the medial and inferior to the 12 rib.
CVA
Costal margin
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Surface Anatomy
Intercostal space
The gap between adjacent ribs is called the intercostal space. Three layers of intercostal muscles span the gap. Inbetween the internal and middle muscle layers (innermost and internal intercostal muscles respectively) lie the intercostal vein, artery and nerve. The vein, artery, and nerve (mneumonic: VAN) are found in that order from top to bottom in the intercostal space.
In addition, the ‘VAN’ is situated just inferior to the upper rib. Therfore if a clinician was to make an incision in the intercostal space in order to access the pleural cavity, they would be advised to make their cut on the superior margin of the lower rib.
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Surface Anatomy
VertebraeThoracic Vertebrae 1 and 2
The first two thoracic spines, like those of the cervical vertebrae, are directed horizontally backwards. T1 is typically more prominent than the spine of C7 and is easily palpated.
Thoracic 3 and 4
The spinous processes of these vertebrae begin to angle obliquely downward. Moving inferiorly from the spine of T2 you should be able to easily distinguish them. The spine of T3 is at the level of the spine of the scapula.
Thoracic 5 through 8
This series of spinous processes become long and course in a more vertical orientation. They overlap the spinous process of the subjacent vertebra. The tip of their process being positioned at the level of the intervertebral disc inferior to the subjacent vertebra. They can be more difficult to enumerate, sometimes feeling like a continuous ridge of bone.
Thoracic 9 and 10
Similar to the spines of thoracic vertebrae 3 and 4, the spines of these vertebrae angle obliquely downward becoming more easily palpable.
Thoracic 11 and 12
The spines of T11 and T12 assume a more horizontal orientation, similar to the first two thoracic spines. The spine of T12 begins to resemble more the spines of the lumbar vertebrae. The tip of its process forming more of a vertical ridge, instead of a rounded or pointed process.
The spine of T12 can be estimated by intersecting the midpoint of a line drawn vertically between the inferior angle of the scapula and the iliac crest.
C7
T1
T5
T12
T9
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Surface Anatomy
Spine of L4
Vertebrae (continued)
Lumbar vertebrae
The spinous processes of the five lumbar vertebrae are easily palpated.
A quick trick helps determine the correct levels of these spines. Connect a string from the superior most point of each iliac crest across the back. The string crosses the spine of the 4th lumbar vertebra. Now that you have located the 4th lumbar spine, it is easy to determine the other lumbar levels.
Sacrum
The sacral spinous processes are much reduced and form a median ridge that is palpable.
Posterior view of Pelvic girdle showing relationshiPs between the sarcum and os coxae
L1
L5
Sacrum
Iliac crest
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Surface AnatomyTT
ClavicleThe clavicle is easily palpated throughout its entire length. Run your fingers along the bone from medial to lateral. Notice that the medial aspect of the bone is straight or slightly convex, whereas the lateral portion of the bone is concave.
Sternal end
Feel the large knob-like sternal end of the clavicle where it forms the sternoclavicular joint with the sternum. Notice how these medial ends of the clavicle help deepen the suprasternal notch of the sternum. Place your fingers on the sternoclavicular joint and move your shoulder. Which joint shows a greater range of motion, the sternoclavicular joint or the acromioclavicular joint?
Acromial end
This end of the clavicle is much less distinct then the sternal end. It is somewhat fattened and joins with the flattened acromion of the scapula. Notice that it is four to five finger breadths form lateral edge of the shoulder. Move the shoulder around to help define where it joins with the acromion of the scapula.
Acromial end of clavicle Sternal end of clavicle
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Surface Anatomy
ScapulaSpine
The spine of the scapula divides the posterior surface of the flattened triangular bone into a supraspinous fossa and an infraspinous fossa. It is easily palpated as the horizontal ridge of bone on the posterior surface of the scapula.
Place your hand on the top of your shoulder with the tips of the fingers on the posterior side. Your finger tips can readily feel the ridge-like spine. Palpate this landmark from its base on the medial aspect of the bone to the point where it widens to become the acromion laterally. The base of the spine sits at the level of the third thoracic vertebra.
Acromion
The acromion is the expanded lateral aspect of the spine of the scapula. Palpate this flattened bony process at the lateral aspect of the shoulder. On the anteromedial part of this flat process feel where it forms the acromioclavicular joint with the clavicle. Move your shoulder around in an attempt to better define the acromioclavicular joint. Notice that the lateral edge of the acromion is approximately one to two finger breadths from the lateral surface of the greater tubercle of the humerus.
Coracoid process
This projection of bone, serving as a muscle attachment for the biceps brachii, pectoralis minor, and coracobrachialis, is easily palpable just inferior to the clavicle a little lateral to mid-clavicle. Palpate this landmark through the anterior portion of the deltoid muscle just lateral to the deltopectoral groove.
Posterior view of right scaPula
AcromionCoracoid process
Spine
anterior view of right scaPula
Acromion
Coracoid process
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Surface Anatomy
Scapula (continued)
Medial margin
Palpate the medial margin of the scapula. Notice that it approximately parallels the spinous processes of the vertebrae. In the anatomical position the medial margin of the scapula is about 4 finger breadths from the spines of the vertebrae.
Superior angle
Notice that the superior angle of the scapula projects above the level of the clavicle. A line that transects the spinous process of the first thoracic vertebra corresponds to the superior angle of the scapula.
Inferior angle
The scapula proves to be a helpful feature to estimate the level of the 7th thoracic vertebra. A horizontal line connecting the inferior angles of the two scapulae crosses the body of the 7th thoracic vertebra. Remember, however, that this corresponds to the tip of the spine of the 6th thoracic vertebra.
Lateral margin
The lateral margin of the scapula can be easily palpated in the posterior wall of the axilla (armpit).
Posterior view of right scaPula
Inferior angle
Superior angle
Lateral margin
Medial margin
T7
Spine of T1
Posterior view of skeleton showing relationshiPs between the sacPula and thoracic vertebrae
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Surface Anatomy
Os coxaThe two os coxae combined with the sacrum and coccyx form the region of the trunk often referred to as the pelvis. The iliac portion of the os coxa, however, is almost totally found within the wall of the lower abdomen. This region is therefore called the false pelvis. The pubis, ischium, sacrum, and coccyx contribute to the walls of the true pelvis. Many parts of the os coxa are readily palpable at the bottom of the trunk.
Pubic crest
This bony ridge is palpable by pressing firmly on the lower abdominal wall just superior to the external genitalia. This marks the anterior boundary between the abdomen and pelvis.
Iliac crest
The iliac crest is the superior most portion of the os coxa. It is situated in the wall of the abdomen. It can be palpated from the anterior superior spine of the ilium to the posterior superior spine of the ilium.
Run your finger along this ridge from one end to the other. Find the superior most point on this crest. This point is referred to as the tubercle of the ilium. A horizontal line between these two points on the ilia intersects the spinous process of the fourth lumbar vertebra at the level of the fourth lumbar interspace.
Anterior superior iliac spine
This is the bony projection at the anterior end of the iliac crest. Place the palm of the hand just below the umbilicus with the fingers directed laterally. With the tip of the middle finger feel for this process. It is the prominent projection at the lateral edge of the soft, lower muscular wall of the abdomen. Compare the distance between these points on individuals of each sex. Notice that the distance between them is narrower in the male.
Posterior superior iliac spine
This is the prominent bony projection at the posterior end of the iliac crest. These can be palpated about three finger breadths from the midline in the lower back. A horizontal line between the posterior superior iliac spines corresponds to the level of the second sacral vertebra.
Ischial tuberosity
This is the prominent landmark of the os coxa that you sit on. While sitting down reach your hand under your buttocks and feel these processes as they push against the chair. These represent the inferior most end of the pelvis.
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Surface Anatomy
Anterior superior iliac spine
Pubic crest
Iliac crest
anterior view of Pelvis
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Surface Anatomy
Posterior superior iliac spine
Ischial tuberosity
Greater trochanter
Posterior view of Pelvis
Iliac crest
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Surface Anatomy
Surface Anatomy of the ThoraxPlanes of the Thorax
Suprasternal notch
Notch at the superior end of the sternum. Easily palpated between the two sternal ends of the clavicle. Corresponds to the intervertebral disc between T2 and T3.
Sternal angle
Transverse ridge on the anterior surface of the sternum located approximately 2.5 inches below the suprasternal notch. Corresponds to the intervertebral disc between T4 and T5.
Inferior angle of scapula
Plalpate down the medial margin of the scapula until you reach the most inferior aspect of the scapula. Corresponds to the vertebral level T7 or the level of the 4th costal cartilage from anterior surface of body.
Xiphisternal joint
A ridge or depression at the inferior end of the sternal body where the body connects to the xiphoid process. Also located by finding the superior aspect of the costal angle between the ribs. Corresponds to the intervertebral disc between T9 and T10.
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Surface Anatomy
TTXiphisternal joint (T9-T10)
Sternal angle (T4-T5)
Sternal notch (T2-T3)
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Surface Anatomy
Summary of Key Levels in the ThoraxStarting with T2 and jumping in even numbered sequences it is easy to remember many key relationships within the mediastinum.
Thoracic vertebra 2
This level demarcates the top of the aortic arch where the major arteries feeding the head and neck arise.
Thoracic vertebra 4
The bottom of this vertebra forms a critical level of anatomy in the mediastinum. At this level many relationships exist:
This level marks the top of the • heart
This is the level of the beginning and ending of the • aortic arch.
This level marks the bifurcation of the trachea and the plane of the • pulmonary arteries.
At this level the azygos vein arches over the trachea and pulmonary artery to • join the superior vena cava.
At this level the thoracic lymphatic duct begins coursing laterally to the left • side.
Thoracic vertebrae 4 to 8
This span of these vertebrae defines the position of the heart.
Thoracic vertebra 8
This level marks the point where the inferior vena cava passes through the central tendon of the diaphragm.
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Surface Anatomy
Inferior vena cava
Aortic arch
Bronchial tree
Pulmonary artery
Superior vena cava
Pulmonary vein
Diaphragm
anterior view
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Surface Anatomy
Bronchial tree
Pulmonary artery
Sympathetic trunk
Azygous vein
Trachea
Esophagus
anterior view
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Surface Anatomy
Pericardial sac
anterior view
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Surface Anatomy
HeartMake points at the following locations:
1) One finger breadth right of the sternum on 3rd costal cartilage
2) One finger breadth left of the sternum in the 2nd intercostal space
3) One finger breadth right of the sternum on the 6th costal cartilage
4) Left of the sternum in the 5th intercostal space at the mid-claviclular line
Connect the points and you have a window that outlines the anterior projection of the heart.
Ventricles
The apex of the heart is positioned to the left in the mediastinum which means that the right ventricle is oriented so that it lies anterior to the left ventricle, just behind the sternum.
Heart Valves
1) Draw a line from the 3rd left costal cartilage to the 6th right costal cartilage just lateral to the sternum.
2) Write the letters P A B T from the top of this line to the bottom of the line, evenly spaced (see figure). This represents the position of the pulmonary (P), aortic (A), bicuspid or mitral (B), and tricuspid (T) valves.
While the above procedure allows you to map the anatomical position of the heart valves, this position is not the best place to hear the heart sounds.
The best place to listen for the valves is as follows:
Aortic - 2nd right intercostal space just lateral to sternum
Pulmonary - 2nd left intercostal space just lateral to sternum
Bicuspid - at apex beat (5th interspace just medial to mid-clavicle)
Tricuspid - Just to the left of the xiphisternal joint
With your stethoscope, auscultate at these points and compare them to the position of the heart valves. You will notice that these spots follow the flow of blood as it passes through the valves. As the blood courses through the valves into the ventricular chambers or the major vessels it carries the valve sounds with it to these locations.
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Surface Anatomy
PP PP
AA
AA
BB
BB
TT
TT
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Surface Anatomy
Pleural SacsFor the right pleural sac make points at the following landmarks:
1) At the sternoclavicular joint
2) At mid-sternum at the sternal angle
3) At mid-sternum at level of 6th costal cartilage
4) On the 8th rib at the mid-clavicular line
5) On the 10th rib at the mid-lateral line
6) At the angle of the 12th rib
7) One finger breadth lateral to the top of the 12th thoracic spine
8) Two finger breadths lateral to the spine of C7
Now connect the points and you have an outline of the right pleural sac.
For the left pleural sac make points at the following landmarks:
1) At the left sternoclavicular joint
2) At mid-sternum at the sternal angle
3) On the lateral edge of sternum at the level of 4th costal cartilage
4) On the lateral edge of sternum at the level of 6th costal cartilage
5) On the 8th rib at the mid-clavicular line
6) On the 10th rib at the mid-lateral line
7) At the angle of the 12th rib
8) One finger breadth lateral to the top of the 12th thoracic spine
9) Two finger breadths lateral to the spine of C7
Now connect the points and you have an outline of the left pleural sac.
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Surface Anatomy
LungsThe lungs sit within the pleural sacs and follow the contours of the sacs with two important deviations:
1) The left lung has a cardiac notch around the ventricles of the heart. This is a region where the lung tissue is absent.
2) Also the lungs do not project into the lowest aspects of the pleural sacs. These regions are referred to as the pleural reflections or recesses.
Outline the cardiac notch on the left side as follows:
Cardiac notch - on the left side from costal cartilage 4 to 6 reflect inward from the line of the pleural sac about two finger breadths.
Outline the bottom of the lungs in the pleural sac as follows:
Inferior borders of lungs are two rib levels higher than the pleural reflections.
Note that the lung and pleural sac extend above the level of the first rib behind the clavicle. The apex of the lung is located one inch above the middle of the medial third of the clavicle.
Pleural recess
Apex of lung
Cardiac notch
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Surface Anatomy
Surface Anatomy of the Abdomen
Summary of Key Levels Associated with DiaphragmStarting with T8 and jumping in even numbered sequences it is easy to remember many key relationships between the diaphragm and the tubular structures that pass through it.
Thoracic vertebra 8
This level marks the point where the inferior vena cava passes through the central tendon of the diaphragm.
Thoracic vertebra 10
This level is the plane of the esophageal hiatus in the diaphragm.
Thoracic vertebra 12
This marks the position of the aortic hiatus for the passage of the aorta and thoracic lymphatic duct.
Abdominal aorta
Esophagus
Inferior vena cava
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Surface Anatomy
Planes of the AbdomenXiphisternal joint
A ridge or depression at the inferior end of the sternal body where the body connects to the xiphoid process. Also located by finding the superior aspect of the costal angle between the ribs. Corresponds to the intervertebral disc between T9 and T10.
Transpyloric plane
Can be mapped on the anterior surface of the body by locating the junction of costal cartilage 9 with 8 and drawing a line across the anterior surface of the body. Corresponds to vertebral level L1
Subcostal plane
Can be mapped on the lateral aspect of the body by locating the bottom of costal arch which is the inferior most point of rib 10. Corresponds to vertebral level L3.
Umbilical plane
This is the horizontal plane through the umbilicus. This plane can be somewhat variable, but on average it corresponds to the level of the disc between L3 and L4.
Iliac intertubercular plane
This is the horizontal plane that crosses the high point of the iliac crest on both sides of the body. Corresponds to vertebral level L4-L5.
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Surface Anatomy
TT
Transpyloric plane (L1)
Subcostal plane (L3)
Iliac intertubercular plane (L4-L5)
Xiphisternal joint (T9-T10)
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Surface Anatomy
DiaphragmDraw the anterior profile of the diaphragm by making the following points:
1) On the right 10th rib in the mid-lateral plane
2) On the right 7th rib in the mid-lateral plane
3) 5th rib at the midclavicular line
4) At the xiphisternal junction
5) 5th intercostal space at the midclavicular line
6) On the left 7th rib in the mid-axial plane
7) On the left 10th rib in mid-axial plane;
Connect these points with a smooth curving line to view the profile of the diaphragm from an anterior view.
LiverThe liver is a large organ tucked beneath the right side of the rib cage having the diaphragm as its roof.
To outline the anterior profile of the liver make the following points:
1) Follow the contour of the diaphragm from the right side to the point just below the left nipple. (See description of diaphragm above. Follow it to the point below the left nipple. Then proceed as outlined in the steps that follow.)
2) Connect the point below the left nipple to the first point on the mid-lateral plane of the right tenth rib by tracing across the xiphoid process and along the bottom margin of the right costal margin.
To outline the posterior profile of the liver make the following points:
1) The posterior outline of the liver is from a point at the tip of the inferior angle of the left scapula to the tip of the inferior angle of the right scapula with a slight depression one vertebra in width as it crosses the midline.
2) Its lower border follows the 11th right rib.
Gall BladderThe gall bladder is difficult, but not impossible, to palpate. If the abdomen is sufficiently relaxed, the fundus portion of the bladder can sometimes be palpated by pressing in under the rib cage at the junction of the rectus abdominis with the right inferior costal margin.
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Surface Anatomy
EsophagusThe esophagus enters the abdomen at the level of thoracic vertebra 10 through the esophageal hiatus of the diaphragm just lateral to the median plane. It is situated deep in the abdomen.
On the anterior surface of the body this corresponds to the junction of ribs seven and eight on the left side. Place the letter E at this point.
Pyloric Sphincter and Upper Arm of DuodenumThis junction between the end of the stomach and the first part of the small intestine lies on the transpyloric plane (remember this is the plane that transects the bottom of the first lumbar vertebra) about two finger breadths to the right of the midline. Place the letter D at this point.
Lesser Curvature of StomachTo outline the lesser curvature of the stomach draw a strongly curved line uniting points E and D that we labeled in the previous two steps. The concavity of the curve should open upward and to the left.
Duodenojejunal Junction and DuodenumThis junction between the retroperitoneal duodenum and the jejunum occurs one to two finger breadths below the transpyloric plane one finger breadth to the left of the midline. Mark this point with the letter J.
Make a strong c-shaped curve, with the concavity of the curve opening to the left, to connect the points D and J which represent the two ends of the duodenum. The lowest aspect of the duodenum should touch the level of the subcostal line. Notice that the two ends of the duodenum are not too far apart.
PancreasThe pancreas runs from inside the c-shaped loop of the duodenum just below the transpyloric line to the hilus of the spleen just above the transpyloric line. This is a deep glandular structure situated posterior to the stomach.
SpleenThe spleen is situated deep in the left upper abdomen. It sits in the posterior arch of left ribs 9, 10 and 11 and does not project further forward then the mid-axillary line. It is separated from the surface by the diaphragm, lungs, and pleura. The transpyloric line crosses the bottom third of the spleen.
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Surface Anatomy
EE
DD
JJ
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Surface Anatomy
Small Intestine (Jejunum and Ileum)The jejunum starts where the duodenum ends, and the terminal portion of the ileum is located at the ileocecal junction described below. In between lies up to 25 feet of small intestine that loops in the central abdomen. Since the small intestine is suspended in the mesentery and undergoes peristalsis, the position of specific bowel segments is variable.
VV
McBurny’s point
Ileocecal Junction and AppendixMake a line by connecting the following points:
1) The anterior superior spine of the ilium
2) The umbilicus
The appendix arises from the base of the caecum in the lower right abdomen. It sits at the point approximately one-third of the distance along this line. This is referred to as McBurny’s point. Just above this point is the ileocecal junction (valve).
Appendix
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Surface Anatomy
Large IntestineThe large intestine consists of the caecum, four colon segments, and the rectum.
Caecum
The caecum lies just above McBurny’s point.
Ascending and descending colon
The ascending and descending colon lie against the lateral abdominal body wall behind the mid-axillary line.
Right and Left Colic Flexures
Also known as the splenic and hepatic flexures respectively, the corners made between the ascending and descending colons occur at the two lateral boundaries of the transpyloric line.
Transverse Colon
The transverse colon can be extremely variable. It can parallel the line between the hepatic and splenic flexures in the horizontal plane or, more often, loop downward into the lower abdomen.
Sigmoid colon
The sigmoid colon can be a short loop that ascends just above the pubis or a long loop that extends up to the level of the transverse colon.
VV
Splenic flexure
Hepatic flexure
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Surface Anatomy
KidneysThe transpyloric plane crosses through the middle of the kidneys. Posteriorly the 12th rib angles across the middle of the kidneys.
The upper pole of the kidney reaches the body of vertebra T12 and the lower pole of the kidney reaches the top of lumbar vertebra 3.
From behind the lower pole of the kidney sits about one to two finger’s breadth above the iliac crest. It also should be realized that since the top of the kidney projects above the 12th rib, there is pleura interposed behind the kidney.
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Surface Anatomy
Celiac artery
Superior mesentaric artery
Inferior mesentaric artery
Aorta and its BranchesThe aorta enters the abdomen at the level of the 12th thoracic vertebra. This is about one vertebral level above the transpyloric line. At this level it has two major branches within one centimeter of each other, the celiac and superior mesenteric arteries.
At the level of the transpyloric line the two renal arteries arise to feed the kidneys. At the bottom of the third lumbar vertebra is the lowest loop in the duodenum.
As the duodenum ascends it crosses the aorta just anterior to the inferior mesenteric artery. This artery arises at L3 which is at the level of the subcostal place.
The bifurcation of the aorta occurs at the fourth lumbar vertebra.
Vascularization of the Abdominal Viscera
Celiac artery & branches vascularize the embryonic foregut (lower espohagus to duodenum including liver and pancreas)
Superior mesenteric artery vascularizes the embryonic midgut (jejunum to transverse colon)
Inferior mesenteric artery vascularizes the embryonic hindgut (descending colon to rectum)
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Surface Anatomy
PP PP
AA
AA
BB
BB
TT
TTEE
DD
JJ
VV
Summary of Surface Anatomy of the Thorax and Abdomen
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Surface Anatomy
Skeletal Landmarks of the Head and NeckSkull
Mastoid process
This is the prominent boney landmark just posterior to the ear. As you palpate downward towards its apex your fingers move onto the sternocleidomastoid muscle.
External occipital protuberance
This is the prominent posterior projection at the back of the occipital bone. As you move laterally from this process towards the base of the mastoid process your fingers are moving along the ridge called the superior nuchal line. This is the superior most border of the thick nuchal musculature.
Styloid process
Place your finger immediately below the ear and just behind the posterior margin of the mandible. Gently push into this sulcus. The tenderness that you feel is your finger pushing on the styloid process of the temporal bone. This delicate process provides attachment for a series of muscles coursing downward into the regions of the pharynx and floor of the mouth.
Mandibular ramus and condylar process
The mandibular ramus is the vertically oriented portion of the mandible. Its lateral surface is the muscle attachment for masseter. Place your finger just anterior to the tragus of the ear. Now by opening and closing the mouth you can feel the condylar process of the mandible articulating in the temporal bone. Move your jaw around and describe the degree of mobility in this joint.
Mandibular ramus
Styloid process
Mastoid process
Condylar process
External occipital protuberance
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Surface Anatomy
Coronoid process
This is the process of the mandible that provides attachment for the powerful jaw closing muscle the temporalis. When the jaw is closed the tip of this process is positioned deep to the zygomatic (cheek) bone. However, if you place your fingers just below the cheek bone on the masseter muscle, then open the mouth you will feel the tip of this process, through the masseter muscle, as it moves inferiorly.
Zygomatic arch
This is the boney bridge that connects the temporal bone to the zygomatic bone. Placing your finger just anterior to the external acoustic meatus and move forward along the boney ridge that attaches to the zygomatic bone.
Pterion
This landmark marks the point where the sutures of the frontal, parietal, sphenoid, and temporal bones meet. It is situated deep to the temporalis muscle in the temporal fossa. It can be located two fingers’ breadths above the zygomatic arch and a thumb’s breadth behind the orbital margin.
Zygomatic arch
Pterion
Coronoid process
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Surface Anatomy
Cervical vertebrae and Nuchal LigamentPlace your fingers on the external occipital protuberance while flexing the head forcefully forward. Moving your fingers inferiorly notice a strong, vertical tendinous ridge. This is the nuchal ligament. While holding your fingers on this ligament bring your head back to the upright position. As you do so notice that the fingers can be pushed deeper into the neck onto the surfaces of the cervical spinous processes.
C1 (Atlas)
The posterior arch of C1 is not palpable. The transverse processes of the atlas project laterally. This increases the lever arm for rotational movements of the skull. These processes are easily alpated in the retromandibular fossa. Place your index finger just behind the posterior marigin of the mandibular ramus. Bringing the tip of the finger inferiorly towards the angle of the mandible, apply pressure. The prominent projection you feel is the transverse process of the atlas.
C2 (Axis)
The superior-most cervical spine that you feel is that of C2.
C7 (vertebrae prominence)
Move your fingers inferiorly over the spines of the cervical vertebrae until you come to the first large, prominent spine. This is the spinous process of C7 often referred to as the vertebra prominens. Note that T1 is often more prominent than C7.
External occipital protuberance
C1 (atlas)C2 (axis)
Transverse process of C1
C7
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Surface Anatomy
Hyoid boneTwo fingers breadth below the sides of the mandible feel the greater cornu of the hyoid bone. As you move you fingers anteriorly along notice that the bone disappears below muscle tissue.
Thyroid cartilage/laryngeal prominenceJust below the hyoid bone the next palpable skeletal structure is the thyroid cartilage. This is typically more prominent in males. Sometimes it is so prominent that the laryngeal prominence, or Adam’s apple, is visable.
Cricoid cartilageMoving your fingers inferiorly from the thyroid cartilage you cross a gap of soft tissue and then onto the cricoid cartilage.
Thyroid
Cricoid
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Hyoid (C3)
Hard Palate (C1)
Planes in the Head and NeckHard palateFirst cervical vertebra
Free margin of maxillary teethSecond cervical vertebra
Hyoid boneThird cervical vertebra
Superior margin of thyroid cartilageFourth cervical vertebra
Cricoid cartilageSixth cervical vertebra
Cricoid (C6)
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Surface Anatomy
Surface Anatomy of the HeadRetromandibular fossaThis is the region just behind the posterior margin of the mandibular ramus. You can easily palpate this region by wedging the index finger up against the base of the external acoustic meatus, just anterior to the mastoid process. Pushing deep into this region you can palpate the styloid process superiorly and the transverse process of the atlas more inferiorly. Your finger is pushing against the parotid gland. The facial nerve course through this region as it bends around the posterior border of the mandible passing through the substance of the parotid gland on its course to innervate the muscles of facial expression.
Temporal fossaThis is the area of the skull situated posterior to the lateral border of the orbit and above the zygomatic arch. It is filled primarily by the temporalis muscle and its tendon. The superficial temporal artery passes through this region. Just deep to the pterion, the H-shaped sutural junction of the sphenoid, frontal, parietal, and temporal bones, is the anterior branch of the middle meningeal artery. This can be an important landmark for determining intracranial relations. The tip of the temporal lobe of the brain is deep to the bone of this region.
Infratemporal fossaThis region is positioned deep to the upper part of the mandibular ramus. A horizontal plane coursing medially from the zygomatic arch separates the temporal fossa from the infratemporal fossa. The infratemporal fossa is that region of soft tissue that forms lateral to the pterygoid process and medial to the coronoid process of the mandible. If you palpate the pterygoid process (see boney landmarks above) you can move the tip of your finger laterally and superiorly. The soft tissue in this region is filling the infratemporal fossa. This is a complex region of anatomy containing the maxillary nerve and vessels with their associated branches and the mandibular nerve and its initial branches. Just medial and superior to this region is the pterygopalatine fossa containing the pterygopalatine ganglion and its nervous connections.
Retromandibular fossa
Temporal fossa
Infratemporal fossa
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Surface Anatomy
GlandsParotid
This large salivary gland can be palpated by pressing through the skin just below and in front of the ear. Part of the gland overlaps the posterior aspect of the masseter muscle.
Parotid duct
Palpate the duct as it crosses the anterior margin of a clenched masseter muscle. It can be easily rolled under the fingers.
Palatine tonsil
This structure can be mapped to the surface by drawing a small oval area over the lower part of the masseter just superior and anterior to the angle of the mandible.
Submandibular gland
This gland can be easily palpated as the large glandular mass just inferior to the angle of the mandible.
Submandibular salivary duct orifice
Notice this raised, fleshy papilla on either side of the frenulum. Try to express saliva from this opening by placing pressure on the submandibular gland.
Parotid gland
Submandibular glasd
Sublingual gland
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Surface Anatomy
NervesFacial nerve
The facial nerve exits the skull through the stylomastoid foramen, located just medial to the mastoid process. It then crosses lateral to the styloid process, below the external acoustic meatus The facial nerve passes through the parotid gland where it splits into its five main branches. These branches remain superficial along their pathway to the muscles of facial expression.
Because the facial nerve is embedded in the parotid gland, parotic abcesses or tumors can cause facial nerve compression and in parotidectomy surgeries facial nerve damage is always a risk.
Temporal nerve
Zygomatic nerve
Buccal nerve
Marginal mandibular nerve
Cervical nerve
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Surface Anatomy
Surface Anatomy of the NeckRegions of the Neck
Anterior triangle
The anterior triangle of the neck is defined by the anterior border of the sternocleidomastoid muscle and the inferior border of the mandible.
Posterior triangle
The posterior triangle of the neck is the region behind sternocleidomastoid.
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Surface Anatomy
Thyroid and Surrounding TissuesCricothyroid ligament
This connective tissue septum can be palpated between the thyroid and cricoid cartilages. This ligament can be an access point to the airways when the glottis is occluded.
Thyroid gland
This gland is most easily palpated lateral to the cricoid cartilage and upper trachea. Find the cricoid cartilage and move a thumb laterally to one side and the first two fingers laterally to the other side. Gently roll the gland under the tips of the digits. If the gland is ‘normal’ you should not feel the outline of the tissue. Therefore during palpation of the thyroid gland a clinician is feeling for the presence of masses or nodules, or glandular enlargement (goiter).
Parathyroid glands
The four parathyroid glands are approximately the size of a pea and are embedded in the posterior aspect of the thyroid gland.
Thyroid
Cricoid
Cricrothyroid ligament
Thyroid gland
Parathyroid gland
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Surface Anatomy
Lymph NodesSuperficial lymph nodes
The most superficial lymph nodes of the neck run horizontally along the inferior margin of the mandible. These can be easily palpated when swollen.
Deep lymph nodes
The deeper lymph nodes of the neck run vertically paralleling the internal jugular vein. These nodes are not as easily palpable unless they are extremely swollen. If this is the case they can be palpated deep to the sternocleidomastoid muscle.
Sternocleidomastoid
Trapezius
Inferior margin of mandible
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Surface Anatomy
Vessels and NervesCommon carotid/Internal carotid
Mapped by a straight line from the sternoclavicular joint to the retromandibular fossa. The carotid artery passes directly anterior to the transverse process of the sixth cervical vertebrae, and in some cases can become compressed at this point.
Bifurcation of common carotid to internal and external carotids occurs at the level of the upper border of the thyroid cartilage.
Vagus nerve
The vagus nerve is situated medial and slightly posterior to the carotid artery in the carotid sheath.
Internal jugular vein
Common carotid artery
Internal carotid artery
External carotid artery
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Surface Anatomy
Internal jugular vein
The hollow between two heads of the sternocleidomastoid marks the internal jugular vein just before it joins the subclavian vein behind the clavicle. This vein runs parallel and just posterior and lateral to carotid artery.
External jugular vein
Descends obliquely from anterior to posterior across the sternocleidomastoid into the posterior triangle of the neck to join the subclavian just behind mid-clavicle.
Internal jugular vein
External jugular vein
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Surface Anatomy
Subclavian artery
The subclavian artery begins just posterior to the sternoclavicular joint and passes between the internal and middle scalene meuscles in the neck. At the highest point of its arch is can rise a couple centimeters above the clavicle. At mid clavical the artery between the clavicle and first rib as it descends towards the axillary region. You can often feel pulsations in supraclavicular fossa as it crosses the first rib.
Subclavian vein
The subclavian vein lies anterior to the subclavian artery and anterior scalene muscle (not shown). The proximal portion of the subclavian vein lies directly posterior to the clavicle. The subclavian vein emerges from under the clavicle just lateral to the midclavicular line, which is the most common site for central venous catheter access.
The junction of the subclavian and internal jugular veins, marking the beginning of the brachiocephalic vein, occurs just deep to the sternal end of the clavicle lateral to the sternoclavicular joint.
Subclavian vein
Internal jugular vein
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Surface Anatomy
Phrenic nerve
The phrenic nerve originates from levels C2-C4 in the spinal cord and innervates the diaphragm. After the three spinal nerve levels join together, the phrenic nerve descends in the neck just anterior to the anterior scalene muscle. As the phrenic nerve approaches the thoracic inlet the nerve is situated just deep to the lower end of the sternocleidomastoid muscle.
Phrenic nerve (branch of C2-C4 spinal nerves)
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Surface Anatomy
Roots of the brachial plexus
These can be palpated with the fingers in the supraclavicular fossa. Just above the middle of the clavicle and just behind the posterior margin of the distal end of the sternocleidomastoid press deeply against the scalene muscles. The roots of the brachial plexus along with the subclavian artery can be compressed here.
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