douglas j. gould-clinical anatomy for your pocket -lippincott williams _ wilkins (2008).pdf
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Clinical Anatomyfor Your Pocket
Douglas J. Gould, Ph.D.Associate Professor, Division of Anatomy
The Ohio State University College of Medicine
Columbus, Ohio
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Library of Congress Cataloging-in-Publication Data
Gould, Douglas J.Clinical anatomy for your pocket / Douglas J. Gould.
p. ; cm.Includes index.ISBN-13: 978-0-7817-9193-9 (pbk. : alk. paper)ISBN-10: 0-7817-9193-6 (pbk. : alk. paper) 1. Human anatomy
Outlines, syllabi, etc. I. Title.[DNLM: 1. Anatomy. QS 4 G696c 2009]QM31.G68 2009611dc22
2008024080DISCLAIMER
Care has been taken to confirm the accuracy of the information present andto describe generally accepted practices. However, the authors, editors, and pub-lisher are not responsible for errors or omissions or for any consequences fromapplication of the information in this book and make no warranty, expressed orimplied, with respect to the currency, completeness, or accuracy of the contents ofthe publication. Application of this information in a particular situation remains theprofessional responsibility of the practitioner; the clinical treatments described andrecommended may not be considered absolute and universal recommendations.
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Health professions curricula around the world are continu-ally evolving: new discoveries, techniques, applications, andcontent areas compete for increasingly limited time with tra-ditional basic science topics such as gross anatomy. It is inthis context that the foundations established in grossanatomy become increasingly important and relevant forabsorbing and applying our ever-expanding knowledge ofthe human body. As a result of the progressively morecrowded curricular landscape, students and instructors arefinding new ways to maximize precious contact, preparation,and study time through more efficient, high-yield presenta-tion and study methods.
Clinical Anatomy for Your Pocket is designed to serve thetime-crunched student. The presentation of gross anatomyin bullet and table format streamlines study and exampreparation. This pocket size, quick reference book isportable, practical, and necessary; even at this small size,nothing is omitted and a large number of clinically signifi-cant facts, mnemonics, and easy-to-learn concepts are usedto complement the tables and inform the reader.
I am confident that Clinical Anatomy for Your Pocket willgreatly benefit all students attempting to learn clinically rel-evant anatomy in a variety of settings, including all graduateand professional gross anatomy programs.
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Preface
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I dedicate this book to my motherMargaret.My first teacher.
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Dedication
I would like to thank the student reviewers for their inputinto this book: I hope that I have done you justice and cre-ated the learning tool that you need. I would also like tothank Dr. Robert DePhilip, the faculty reviewer of ClinicalAnatomy for Your Pocket, whose suggestions have provedinvaluable in creating an accurate and functional tool forstudents.
Acknowledgments
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Contents
v
Preface iiiDedication and Acknowledgments iv
1 Thorax . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Abdomen . . . . . . . . . . . . . . . . . . . . . 33
3 Pelvis . . . . . . . . . . . . . . . . . . . . . . . . 77
4 Back . . . . . . . . . . . . . . . . . . . . . . . 113
5 Lower Limb . . . . . . . . . . . . . . . . . . 126
6 Upper Limb . . . . . . . . . . . . . . . . . . 158
7 Head . . . . . . . . . . . . . . . . . . . . . . . . 196
8 Neck . . . . . . . . . . . . . . . . . . . . . . . . 237
List of Mnemonics 260Index 261
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Bone Characteristic SignificanceTypical ribs (39)
Atypical ribs (12, 1012 )
Bones of the thoracic wall
Head
NeckTubercle
Body
1st and 2ndribsheads
Ribs 1012sternalattachments
Bears 2 facets that articulate withvertebra of same number and thevertebra superior to itJoins head with body of rib Articulates with transverse process
of vertebra of same number Located at junction of neck and body Bears pronounced angle Inferior internal border has costal
groove for intercostalneurovascular elements
The heads of the first 2 ribs onlyattach to one vertebral body, unliketypical ribs that attach to two
The 1st and 2nd ribs haveadditional tubercles for muscleattachments
INTRODUCTIONThe thorax is that portion of the trunk inferior to the neck(superior thoracic aperture) and superior to the diaphragm,to which the pectoral girdle and upper limbs are attached.
THORACIC WALLThe bones of the thoracic wall are the ribs and sternum.Ribs 39 possess characteristics common to the majority ofribs and so are considered typical, whereas ribs 12 and1012 have specializations or are lacking typical characteris-tics and so are considered atypical.
1Thorax
1
(continued)
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2 CLINICAL ANATOMY FOR YOUR POCKET
Bone Characteristic Significance
Thoracic vertebrae (12)
Sternum
Bones of the thoracic wall (continued)
Body
Spinous process
Transverseprocess
Laminae andpedicles
Vertebralforamen
Vertebralnotchessuperior andinferior
Articulatingprocessessuperior (2) andinferior (2)
Manubrium
Sternal angle
Body
Xiphoid process
Ribs 1012 attach indirectly (rib 10)or not at all to the sternum (ribs1112, the floating ribs)
Supports weight
Serve for muscle attachments
Form vertebral arch that enclosesspinal cord
Formed from vertebral arch andposterior aspect of vertebral body
Encloses spinal cord Successive vertebral foramen form
vertebral canal
Inferior and superior notches ofadjacent vertebrae formintervertebral foramen that permitspassage of spinal nerves betweenthe vertebral canal and periphery
Form zygapophyseal joints witharticulating processes on adjacentvertebrae
Superior part of sternum Superior border bears jugular notch Clavicular notches (2) are found on
each side of the jugular notch forarticulation with the clavicles
Landmark for the 2nd ribs costalcartilage articulation with thesternum
Marks articulation betweenmanubrium and body
Bears costal notches along lateralborder for articulation with costalcartilages
Most inferior part of sternum Landmark for central tendon of
diaphragm, superior margin of liver,and inferior border of heart
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Additional ConceptTrue, False, and Floating RibsRibs 17 are considered true ribs, as they attach to thesternum via their individual costal cartilages; ribs 810 areconsidered false ribs, as they attach indirectly to the ster-num via the costal cartilages of more superior ribs; ribs1112 are considered floating ribs, as they do not connectto the sternum.
Clinical SignificanceRib FractureFracture of the upper ribs may injure the lungs and of lowerribs may damage the liver or spleen or may tear thediaphragm. All rib fractures are painful owing to the brokenpieces moving during respiration, coughing, sneezing, orlaughing.
Sternal PunctureA wide-bore needle may be used to harvest bone marrowfrom the sternum for transplantation or biopsy.
CHAPTER 1 | THORAX 3
Proximal DistalMuscle attachment Attachment Innervation Main ActionsExternal Inferior Superior Intercostal Elevate ribsintercostal aspect of ribs aspect of ribs nervesInternal Depress andinter- elevate ribscostalInnermostintercostalTransverse Posterior inferior Posterior Depress ribsthoracic aspect of aspect of
sternum costal cartilages 26
Subcostal Deep aspect of Superior Depress andlower ribs, near aspect elevate ribsangles of 23 ribs
below proximal attachment
Muscles of the thoracic wall(Figures 1-2 and 1-4)
(continued)
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4 CLINICAL ANATOMY FOR YOUR POCKET
Muscles of the thoracic wall (continued)
Diaphragm Sternum, Central Motor: Increases inferior 6 ribs tendon of phrenic; the volumeand their costal the diaphragm sensory: of the thoraxcartilages, medial phrenic and to cause& lateral arcuate intercostal inspirationligaments, and nerves1st 3 lumbar vertebrae
Levator T7T11 Subjacent ribs C8T11 Elevate ribscostarum transverse between posterior
processes tubercle and ramiangle
Serratus Nuchal ligament, 2nd4th ribs 2nd5th posterior C7T3 spinous superior intercostalssuperior processes bordersSerratus T11L2 spinous 8th12th ribs 9th11th Depress ribsposterior processes inferior borders, intercostalsinferior near angles and subcostal
Lung
Visceral pleura
Parietal pleura
Innermost intercostalmuscleIntercostal vein,artery, nerve
Internal intercostal muscleExternal intercostal muscle
Needle
Tube
Pleural cavity
FIGURE 1-1. Thoracocentesis. An intercostal nerve block (needlein image) produces anesthesia of an intercostal space by introduc-tion of an anesthetic agent around the intercostal nerve and its col-laterals. The tube in the diagram indicates the position for thoraco-centesis. (From Dudek RW, Louis TM. High-Yield Gross Anatomy.3rd ed. Baltimore: Lippincott Williams & Wilkins; 2008:56.)
Proximal DistalMuscle attachment Attachment Innervation Main Actions
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CHAPTER 1 | THORAX 5
Additional ConceptDiaphragmThe diaphragm has three openings that permit passage ofstructures between the thorax and abdomen. These open-ings are found at T8caval foramen, T10esophageal hia-tus, and T12aortic hiatus.
Clinical SignificancePhrenic Nerve InjuryPhrenic nerve injury results in hemiparalysis of thediaphragm and paradoxical movement during inspiration.Instead of descending during inspiration, the paralyzedhalf ascends in response to increased intra-abdominalpressure.
Sternum
T8
T10
T12
Superiormesenteric artery
Celiac trunk
Aorta
Esophagus
Inferiorvena cava
Diaphragm
FIGURE 1-2. Holes in diaphragm. There are three large aper-tures in the diaphragm for major structures to pass to and fromthe thorax into the abdomen. The caval opening for the inferiorvena cava (IVC), most anterior, is at the T8 level and to the rightof the midline; the esophageal hiatus, intermediate, is at T10 andto the left of the midline; the aortic hiatus for the aorta passesposterior to the vertebral attachment of the diaphragm in themidline at T12. (From Moore KL, Dalley AF. Clinically OrientedAnatomy. 5th ed. Baltimore: Lippincott Williams & Wilkins;2006:329.)
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6 CLINICAL ANATOMY FOR YOUR POCKET
Artery Origin Description
Internal Subclavian Gives rise to anterior intercostals and thoracic musculophrenic
Anterior Internal Supplies intercostal muscles and intercostals thoracic (16) and parietal pleura
musculophrenic (79)
Posterior Supreme intercostalintercostals (12) and thoracic aorta
Subcostal Thoracic aorta Supplies anterolateral abdominalmusculature
Arterial supply of the thoracic wall(Figures 1-1 and 1-4)
Nerve Origin Structures Innervated
Nerves of the thoracic wall(Figures 1-1 and 1-4)
Intercostals Anterior rami Intercostal muscles and parietal pleuraof T1T11
Subcostal Anterior Abdominal wall musculature and rami of T12 parietal pleura
Rami Connect Whiteconvey presynapticcommunicantes intercostals sympathetic fibers from spinal nerve
and subcostal to sympathetic chain and visceralnerves to afferents to spinal nervessympathetic Grayconvey postsynaptictrunk sympathetic fibers from the
sympathetic chain to spinal nerve
Sympathetic Sympathetic Composed of sympathetic gangliatrunk chain ganglia containing postsynaptic sympathetic
(paravertebral cell bodies connected by ascendingganglia) and descending fibers
Thoracic Sympathetic Convey presynaptic sympathetic fiberssplanchnics chain: to the prevertebral ganglia of the
Greater abdomen; convey visceral afferents to T5T9 the sympathetic chain
LesserT10T11
LeastT12
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Additional ConceptVenous DrainageVenous drainage of the thoracic wall generally parallels arte-rial supply. However, the posterior intercostal veins drain tothe azygos system, which is discussed with the posteriormediastinum.
CHAPTER 1 | THORAX 7
Joint Type Articulation Structure
1st Cartilaginous 1st costal Joint strengthened by sternocostal cartilage sternocostal radiate
with manubrium ligaments
2nd7th Synovial 2nd7th costal sternocostal cartilages with
sternum
Sternoclavicular Synovial Sternal end of Divided into twoclavicle with compartments bymanubrium and articular disc1st costal cartil- Joint strengthened age by anterior and
posterior sternoclavi-cular and costoclavi-cular ligaments
Manubriosternal Cartilaginous Manubrium with Joint often fuses inbody of sternum older people
Xiphisternal Xiphoid process with body of sternum
Interchondral 6th9th: Costal cartilages Strengthened bysynovial of adjacent ribs interchondral
9th10th: 610 ligamentsfibrous
Costochondral Cartilaginous Costal cartilage Bound together bywith end of rib periosteum
Little if any movement permitted
Intervertebral Symphysis Adjacent verte- Strengthened by bral bodies anterior and posterior
longitudinal ligaments and the anular ligament
Joints of the thoracic wall
(continued)
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BREASTThe breast extends from the sternum to the midaxillary lineand from ribs 26. It rests on the pectoral fascia and the fas-cia over serratus anterior.
8 CLINICAL ANATOMY FOR YOUR POCKET
Joint Type Articulation Structure
Joints of the thoracic wall (continued)
Costovertebral Synovial Head of ribs with Strengthened byvertebral bodies radiate and intra-at same level articular ligamentsand the 1st, 11th, 12th, andvertebral body and sometimes 10th superior to it ribs articulate only
with vertebral body of same level
Costotransverse Tubercle of rib Strengthened by with transverse lateral and superiorprocess of costotransverse vertebral body ligamentsat same level 11th and 12th ribs do
not participate in costotransverse joints
Structure Description SignificanceMammary Modified sweat glands Accessory reproductive glands Arranged in 1520 lobules organs in the female
Contained within thebreast
Areola The skin around the nipple Turns a darker color Studded with sebaceous during pregnancy
glands that form eleva- Stimulation from thetions suckling infant triggers
ejection and production of milkthe let-down reflex
Nipple Round, raised area of skin Stimulation from the sucklingin the center of the areola infant triggers erection of
Surrounded by circularly the nipple and the ejectionarranged smooth muscle and production of milkfibers that cause erection on stimulation
Structure of the breast(Figure 1-3)
(continued)
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Additional ConceptThe size and shape of the adult female breast is due to itscontained fat, which forms the bulk of the breast tissue.
CHAPTER 1 | THORAX 9
Structure Description Significance
Structure of the breast (continued)
Suspensory Connective tissue supports Provide support for theligaments that extend from the dermis breast
to the pectoral fascia If invaded by carcinoma, the ligaments shorten and produce skin dimpling and nipple inversion
Lactiferous duct 1520 total, open onto Drain the mammary glandularthe nipple tissue
Lactiferous sinus Expansion of lactiferous duct Function as a milk reservoir near the nipple during lactation
Axillary process Extension of breast tissue High percentage of breast into the axilla tumors occurs here
Externalabdominal
oblique
Serratusanterior
Axillary tail
Areola
Nipple
Lactiferous ducts
Lactiferous sinusLobes Fat
FIGURE 1-3. Breast, anterior view. (From Tank PW, Gest TR.LWW Atlas of Anatomy. Baltimore: Lippincott Williams & Wilkins;2009:39.)
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Additional ConceptVenous drainage of the breast parallels the arterial supplyand drains mainly to the axillary vein, whereas some venousdrainage is to the internal thoracic vein.
10 CLINICAL ANATOMY FOR YOUR POCKET
Artery Origin Description
Medial mammary Internal thoracic Supplies medial aspect of breastbranches
Anterior intercostals
Lateral mammary Lateral thoracic Supplies lateral aspect of breastbranches
Thoracoacromial Axillary Supplies breast through pectoral branches
Posterior Thoracic aorta Supplies lateral aspect of breast intercostals through lateral mammary branches
Arterial supply of the breast
Clinical SignificanceQuadrantsThe breast is divided into four quadrants for the anatomiclocation and description of pathologies. The inferior quad-rants are less vascular and, therefore, the preferred area forsurgical incisions when necessary.
Retromammary SpaceBetween the breast and the pectoral fascia is the retromam-mary space, which permits movement of the breast on thethoracic wall. Diminishment of this movement may indicatepathology.
Nerves of the breast
Nerve Origin Structures Innervated
Anterior cutaneous Intercostal Sensory to skin of breastbranches nerves 46 Postsynaptic sympathetic fibers to Lateral cutaneous the smooth muscle of the nipple and branches blood vessels
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Additional ConceptThe contralateral breast receives a significant amount oflymphatic drainage.
MISCELLANEOUSThoracic cavityThe thoracic cavity is bounded by the thoracic walla flexi-ble musculoskeletal cage. It is divided into 2 laterally placedpleural cavities and a central regionthe mediastinum.Thethoracic cavity contains the heart, lungs, thymus, trachea,esophagus, and multiple neurovascular elements.
CHAPTER 1 | THORAX 11
Lymphatic Structure Description DrainageSubareolar Located deep to the nipple, Drains lymph from the nipple,lymphatic areola, and around the areola, and glandular tissueplexus lobules of the glandular of the breast to regional nodes
tissue of the breastAxillary Composed of pectoral, Drains 75% of lymph from lymph nodes humeral, subscapular, the breastthe lateral
central, and apical nodes quadrant in particularParasternal Located along the sternum Drains mostly lymph from lymph nodes the medial quadrant of the
breastAbdominal Located inferior to the dia- Drains mostly lymph from thelymph nodes phragm in the abdominal inferior quadrants of the breast
cavity; also known as inferior phrenic lymph nodes
Infraclavicular Located inferior to the Drains lymph from the axillarylymph nodes clavicle lymph nodesSupraclavi- Located superior to the cular lymph claviclenodesSubclavian Formed from efferent vessels On the rightjoins withlymphatic of the axillary nodes, apical bronchomediastinal & trunk in particular jugular trunks to form
the right lymphatic duct On the leftjoins the
thoracic duct
Lymphatics of the breastKnowledge of the lymphatic drainage of the breast is impor-tant owing to the high incidence of breast carcinoma.
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Area Structure SignificanceSuperior Boundaries: Also known as the thoracicthoracic Anteriormanubrium inletaperture PosteriorT1 Allows passage of the
Lateral1st ribs and their trachea, esophagus, andcostal cartilages neurovascular elements
between the thoracic cavity and the neck
Inferior Boundaries: Also known as the thoracicthoracic Anteriorxiphisternal outletaperture joint Closed by the diaphragm
Anterolateralcostal Allows for passage of cartilages of ribs 710 the inferior vena cava, aorta,the costal margin and esophagus between the
PosteriorT12 thoracic cavity and abdomen Posterolateral11th and
12th ribsIntercostal Space between adjacent ribs Contains intercostal musclesspace and costal cartilages and intercostal neurovascular
elementsSuperior Superior bordersuperior Contains superior vena cava,mediastinum thoracic aperture brachiocephalic veins, arch of
Inferior borderplane aorta, thoracic duct, esophagus,passing from sternal angle trachea, left & right vagusthrough the T4T5 nerves, left recurrent laryngealvertebral level nerve and left & right phrenic
Lateral borderspleural nerves, and the thymuscavities
Inferior Superior borderplane Subdivided by the pericardial mediastinum passing from sternal angle sac into anterior, middle, and
through the T4T5 posterior mediastinavertebral level
Inferior borderdiaphragm Lateral borderspleural
cavitiesAnterior Most anterior part of the Contains the thymus, loose mediastinum inferior mediastinum connective tissue, sternoperi-
Bounded anteriorly by the cardial ligaments, lymphsternum and transverse nodes, and fatthoracic muscle and post-eriorly by the pericardium
Middle Middle part of inferior Contains the heart, pericardialmediastinum mediastinum sac, roots of the great vessels,
arch of the azygos vein, and primary bronchi
Posterior Most posterior part of the Contains the thoracic aorta,mediastinum inferior mediastinum esophagus, azygos and
hemiazygos veins, vagus nerves, thoracic duct, sympathetic trunks, and splanchnic nerves
12
Thoracic cavity (continued)
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MnemonicV-A-N: Intercostal neurovascular elements are arrangedfrom superior to inferior as:
intercostal Veinintercostal Arteryintercostal Nerve
Clinical SignificanceThoracic Outlet SyndromeObstructions in the root of the neck may affect structurespassing through the superior thoracic aperture; problems areoften manifested in the upper limb.
CHAPTER 1 | THORAX 13
Structure Significance
Organ
Esophagus Located posterior to the trachea, anterior to vertebral bodies Begins at inferior aspect of pharynx (C6) Terminates by entering the stomach after passing through the
esophageal hiatus (T10) of the diaphragm
Nerve
Esophageal Formed of parasympathetic fibers from the vagus nerves andplexus sympathetic fibers from sympathetic chain ganglia and the
greater splanchnic nerve Supply glands and musculature of inferior 2/3 of esophagus
Sympathetic Located on either side of the vertebral column along posterior trunks wall of the thorax
Chain of paravertebral ganglia containing presynaptic sympathetic cell bodies
Ganglia connected by presynaptic sympathetic and visceral afferent fibers
Connected to thoracic spinal nerves by rami communicantes
Thoracic Greater, lesser, and leastsplanchnic Convey presynaptic sympathetic fibers from T5T12nerves to prevertebral ganglia of the abdomen
Convey visceral afferents from the abdomen
Vessel
Thoracic Continuation of the arch of the aorta; becomes abdominal aorta aorta after passing through the aortic hiatus (T12) of the
diaphragm Found to the left of thoracic vertebral bodies
Posterior mediastinum
(continued)
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Clinical SignificanceEsophageal ConstrictionsThree constrictions of the esophagus occur where it is compressed by, from superior to inferior: (1) arch of theaorta, (2) left main bronchus, and (3) the diaphragm.These constrictions are areas susceptible to damage from swallow-ing caustic substances and are places where ingested objects
14 CLINICAL ANATOMY FOR YOUR POCKET
Structure Significance
Posterior mediastinum (continued)
Bronchial Left: branches of thoracic aortaarteries Right: branches of posterior intercostal arteries
Supply oxygenated blood to the tissues of the lungPericardial Branches of thoracic aorta and pericardiophrenic arteriesarteries Supply the pericardiumPosterior Branches of thoracic aortaintercostal Supply intercostal spaces 311arteries9 pairsSuperior Branches of the thoracic aortaphrenic Supply the diaphragmarteriesEsophageal Branches of the thoracic aortaarteries Supply the esophagusSubcostal Branches of the thoracic aortaarteries Supply body wall inferior to the 12th ribsThoracic Conveys lymph from entire body, except the right upper limb,duct right aspect of the thorax and right side of head & neck
Begins in abdomen at chyle cistern and empties into the junction of left internal jugular vein and left subclavian vein
Found along the vertebral column between the azygos vein and esophagus
Azygos vein Drains mediastinum and posterior thoracic & abdominal walls on the right; found on right side of vertebral bodies
Begins in the abdomen and terminates by emptying into superior vena cava
Receives hemiazygos and accessory hemiazygos veins at the T8T9 vertebral level
Hemiazygos Drains mediastinum and posterior thoracic and abdominal vein walls on the left as high as T9 vertebral level, where it
crosses to the right side to enter the azygos veinAccessory Drains mediastinum and posterior upper thoracic wall on the hemiazygos left as far inferiorly as T8 vertebral level where it crosses tovein the right side to enter the azygos vein
The trachea is presented with the superior mediastinum.
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may become lodged; the constrictions are visible on radi-ographs and are useful landmarks.
Azygos VeinsThe azygos system provides a collateral pathway for venousblood that connects the superior and inferior vena cavae.
MnemonicFour birds of the thorax:
esophaGOOSEvaGOOSE nerve azyGOOSE veinthoracic DUCK
CHAPTER 1 | THORAX 15
Sympatheticchain
Azygosvein
Rightprimary
bronchus
Intercostalvein, artery,
and nerve
Cut edgeof costal
pleura
Esophagus
Trachea
Leftprimarybronchus
Thoracicduct
Diaphragm
FIGURE 1-4. Posterior mediastinum viewed from the right: parietalpleura is intact on left side and partially removed on right. A portion ofesophagus, between bifurcation of trachea and diaphragm, is alsoremoved. (From Agur AMR, Dalley AF. Grants Atlas of Anatomy, 12th
ed. Baltimore: Lippincott Williams & Wilkins; 2009:82.)
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16 CLINICAL ANATOMY FOR YOUR POCKET
(continued)
Superior mediastinum(Figure 1-5)
Structure SignificanceLigamentum Remnant of the ductus arteriosus (shunt for blood from the arteriosum fetal pulmonary trunk to aorta)
Connects left pulmonary artery to the arch of the aorta Left recurrent laryngeal nerve wraps around to then ascend to
the larynxOrganThymus Located mostly in the superior mediastinum
Lymphatic organ that involutes after puberty and is replacedby fat
Trachea Located anterior to the esophagus Begins at cricoid cartilage of the larynx Terminates at the level of the sternal angle into 2 main bronchi Skeleton of posteriorly oriented U-shaped rings, posterior
deficiency spanned by the trachealis muscleEsophagus Located posterior to the trachea and anterior to the vertebral
bodies Begins at inferior aspect of the pharynx, terminates by entering
the stomach after passing through the esophageal hiatus (T10) of the diaphragm
NerveLeft vagus Found anterior to the arch of the aorta where it gives off the
left recurrent laryngeal nerve Passes posterior to the root of the lung, where it ramifies
to contribute to the pulmonary, cardiac, and esophageal plexuses
Right vagus Found anterior to the right subclavian artery, where it gives off the right recurrent laryngeal nerve
Passes posterior to the root of the lung, where it ramifiesto contribute to the pulmonary, cardiac, and esophageal plexuses
Left Branch of left vagus nerve as it passes over the anterior recurrent surface of the arch of the aortalaryngeal Ascends to the larynx between the trachea and esophagusRight Branch of the right vagus nerve as it passes over the anteriorrecurrent surface of the right subclavian arterylaryngeal Ascends to the larynx between the trachea and esophagus in
the tracheoesophageal grooveLeft phrenic Passes anterior to the root of the lung, found between thenerve fibrous pericardium and mediastinal pleuraRight Sole motor supply to the diaphragmphrenic Sensory to central aspects of diaphragmnerve
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Additional ConceptLymphatic DrainageIn addition to the brachiocephalic veins forming at the junc-tion of the internal jugular and subclavian veins, it is also thepoint where the right lymphatic duct joins the venous sys-tem on the right and the thoracic duct on the leftknownas the jugular angle.
CHAPTER 1 | THORAX 17
Structure Significance
Superior mediastinum (continued)
Vessel
Left Formed by junction of the internal jugular and subclavian veinsbrachioce- The left and right brachiocephalic veins join to form the phalic vein superior vena cava
Right brachioce-phalic vein
Superior Drains most venous blood from structures superior to the vena cava thorax into the right atrium
Arch of the Continuation of the ascending aorta; becomes the thoracic aorta aorta as it descends
Gives off 3 branches in the superior mediastinum:1. brachiocephalic trunk2. left common carotid artery3. left subclavian artery
Left vagus nerve courses on its anterior surface
Brachioce- 1st branch of the arch of the aortaphalic trunk Terminates by dividing into the right common carotid and right
subclavian arteries Indirectly supplies the right side of head and neck and right
upper limb through its branches
Left 2nd branch of the arch of the aortacommon Terminates in the neck by dividing into internal & external carotid carotid arteriesartery Indirectly supplies left side of head and neck through its
branches
Left sub- 3rd branch of the arch of the aortaclavian Continues as it passes over the lateral border of the 1st rib toartery become the left axillary artery
Supplies the left upper limb
The thoracic duct is presented with the posterior mediastinum.
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MEDIASTINUMAdditional ConceptPericardiumThe pericardium receives its arterial supply from the peri-cardiacophrenic arteries, which run with the phrenic nervebetween the mediastinal pleura and the fibrous pericardium.Sensory innervation to the pericardium is carried via thephrenic nerves.
18 CLINICAL ANATOMY FOR YOUR POCKET
Structure Description SignificancePericardial Formed of 2 layers: Double-layered fibroseroussac 1. outerfibrous sac that encloses the heart
pericardium Fused with adventitia of the2. innerparietal layer of great vessels
serous pericardium Attached to the deep surface of the sternum by the sterno-pericardial ligament
Fuses with the central tendon of the diaphragm; therefore, moves during respiration
Visceral layer Mesotheliumsimple Also known as the of serous squamous epithelium epicardiumthe outer layer pericardium of the heartParietal layer Lines inner surface of fibrousof serous peri- pericardiumcardiumPericardial Potential space between Filled with serous fluidcavity the layers of serous peri- Allows heart to beat in a
cardium friction free environmentFibrous peri- Strong collagenous outer Inflexible nature preventscardium layer of the pericardial overfilling of the heart
sac Phrenic nerve travels Fuses with adventitia of inferiorly through the thorax
great vessels, central on its lateral surfacetendon of the diaphragm, and sternum
Transverse Extension of the pericardial Allows for control of blood out sinus cavity posterior to the pul- of the heart during surgery
monary trunk and aortaOblique sinus Extension of the pericardial Ends as a cul-de-sac between
cavity on the posterior the pulmonary veinsaspect of the heart
Structure of the pericardial cavity(Figure 1-5)
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CHAPTER 1 | THORAX 19
Clinical SignificancePericarditisInflammation of the pericardium that may cause chest painand pericardial friction rub, which can be detected duringauscultation.Pericardial TamponadeAn increase in fluid in the pericardial cavity (e.g., fromchronic inflammation) may decrease the efficiency of theheart as it is compressed. Pericardiocentesis is the drainageof excess fluid from the pericardial sac.
Structure of the heart(Figure 1-6)
The heart is contained within the pericardial sac. It islocated within the middle mediastinum, left of the medianplane in the thorax. The heart is essentially a cone-shapedmuscular pump, the apex of which is directed anteroinferi-orly to the left and the base posterolaterally to the right.Thebase of the heart is the location of the superior vena cava,ascending aorta and pulmonary trunk.
Structure Description SignificanceHeart Anterior (sternocostal) Anteriorformed mainly by surfaces Inferior (diaphragmatic) right ventricle
Right and left pulmonary Diaphragmaticformedsurfaces mainly by left ventricle
(some right ventricle) related to central tendon of diaphragm
Left pulmonaryformed mainly by left ventricle, related to cardiac notch of left lung
Right pulmonaryformed mainly by right atrium
Pectinate Muscular ridges found on Found in primitive parts of muscles the walls of the atria both atria
Presence indicates rough part of atrial walls
Trabeculae Muscular ridges found on Found in primitive parts of carneae the walls of the ventricles both ventricles
Serve to increase mechanical advantage during ventricularcontraction
Presence indicates rough part of ventricular walls
(continued)
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20 CLINICAL ANATOMY FOR YOUR POCKET
Structure Description SignificancePapillary Conical muscular projections Contract immediately beforemuscles from the ventricular wall ventricular contraction to pull
that attach to chordae chordae tendineae taut to tendineae prevent backflow during
ventricular contraction (systole)
Chordae Attached to margins of Hold valve cusps taut duringtendineae atrioventricular valves and ventricular contraction to
papillary muscles prevent backflow (regurgitation)Interatrial Muscular septum separating Right sidelocation of fossa septum the atria ovalis: remnant of foramen
ovale, an embryologic shunt for blood from the right atrium to the left atrium
Interventricular Composed of a membranous Separates right and left septum (superior) part and a muscular ventricles
(inferior) partRight and Right3 cusps Rightpermits passage of left atrioventri- (tricuspid) blood from right atrium to cular valves Left2 cusps right ventricle and prevents
(bicuspid, mitral) backflow in the reverse direction
Leftpermits passage of blood from left atrium to left ventricle and prevents backflow in the reverse direction
Fibrous Collagenous skeleton of Provides stability and attach-skeleton heart ment for valve cusps and
Forms fibrous rings that muscle fiberssurround heart orifices Provides electrical insulation
Fibrous trigones connect between the atria and rings ventricles
Right atrium Forms right border of heart Receives deoxygenated blood from the superior and inferior vena cavae & coronary sinus
Sinus venarum Smooth-walled part of right Formed from incorporation of atrium the embryonic sinus venosus
during developmentSulcus Groove on outside of right External representation of terminalis atrium meeting of primitive atrium and
sinus venarum derived tissuesCrista Ridge on inside of right Internal representation of terminalis atrium meeting of primitive atrium and
sinus venarum derived tissues
Structure of the heart (continued)
(continued)
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CHAPTER 1 | THORAX 21
Structure Description SignificanceRight auricle Small, conical projection Remnant of primitive right
from right atrium atriumLeft atrium Forms most of base of heart Receives oxygenated blood
from 4 pulmonary veinsLeft auricle Finger-like projection from Remnant of primitive left
left atrium atriumRight Forms inferior border of Receives blood from right ventricle heart atriumConus Smooth-walled superior Entry to the pulmonary trunkarteriosus aspect of right ventricle(infundibulum)Supraventri- Muscular ridge on inside of Separates rough part of cular crest right ventricle chamber from smooth-walled
part of chamberSeptomarginal Muscular ridge that extends Conveys right atrioventricular trabecula from the inferior aspect of bundlepart of conduction (moderator the interventricular septum system, to the anterior band) to the base of the anterior- papillary muscle
most papillary musclePulmonary 3 semilunar cusps Prevents backflow valve Located at apex of conus (regurgitation) of blood during
arteriosus ventricular relaxation (diastole)Pulmonary Located between cup-shaped Prevent valve cusps from sinuses semilunar valve leaflets and sticking to pulmonary trunk
dilated pulmonary trunk wall wall during ventricular contraction
Left ventricle Forms apex and left border Thicker wall (4) than right of heart ventricle because it pumps
against greater pressureAortic vesti- Smooth-walled superior Entry to ascending aortabule aspect of left ventricleAortic valve 3 semilunar cusps Prevent backflow
Located near origin of (regurgitation) of blood during ascending aorta ventricular relaxation (diastole)
Aortic sinuses Located between cup- Prevent valve cusps from shaped semilunar valve sticking to ascending aorta leaflets and dilated ascend- wall during ventricular ing aorta wall contraction
Right and left sinus give origin to the right and leftcoronary arteries respectively
Structure of the heart (continued)
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Additional ConceptHeart is a Double PumpRight side of the heart: right atrium receives deoxygenatedblood from the vena cavae; the right ventricle pumps thisblood to the lungs for oxygenation via the pulmonary trunk.Left side of the heart: left atrium receives oxygenated bloodfrom the pulmonary veins; the left ventricle pumps thisblood to the body via the aorta.
Walls of the HeartThe walls of all 4 chambers of the heart consist of the samethree layers from superficial to deep:
epicardiumlayer of mesothelium; also known as viscerallayer of serous pericardium
myocardiummiddle layer composed of cardiac muscletissue
endocardiumlayer of endothelium that lines heartchambers and valves
22 CLINICAL ANATOMY FOR YOUR POCKET
Right brachiocephalic vein
Left brachiocephalic veinSuperior vena cava
Reection ofpericardium
Right auriclePectinatemuscles
Fossaovalis
Rightatrium
Inferiorvena cava
Tricuspid valvePapillary
muscle
Rightcoronary
artery
Left subclavian arteryLeft common carotid artery
Brachiocephalic trunkArch of aorta
Ligamentumarteriosum
Pulmonarytrunk
ConusarteriosusLeft auricle
Leftventricle
Abdominalaorta
Apex of heart
Muscularinter-ventricularseptum
Chordaetendineae
Moderatorband
Anterior inter-ventricularartery
FIGURE 1-5. Heart. Right interior view. (Asset provided byAnatomical Chart Company.)
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AuscultationAuscultation of the valves: each of the 4 valves of the heartis heard best at specific locations on the thoracic wall:
bicuspid valve5th intercostal space on the lefttricuspid valve4th intercostal space to the left of the
sternumpulmonary valve2nd intercostal space to the left of the
sternumaortic valve2nd intercostal space to the right of the
sternum
VentriclesVentricle characteristicsfewer, larger papillary muscles,more numerous trabeculae carneae, fewer, thicker atrioven-tricular valve cusps and fewer, thicker chordae tendineae arecharacteristics of the left ventricle owing to its increasedworkload relative to the right ventricle.
Clinical SignificanceForamen OvaleIncomplete closure of the foramen ovale occurs in15%25% of adults, it is typically asymptomatic.
Septal DefectsThe membranous part of the interventricular septum isthe most common site of interventricular septal defects;severe defects may result in hypertension and cardiac failure.
CHAPTER 1 | THORAX 23
Nerves of the heart
Nerve Origin Structures InnervatedSuperficial Sympathetic Sympatheticterminate on SA and cardiac plexus sympathetic AV nodes, increases heart rate and
trunks force of contraction, produces vasodi- Parasym- lation of coronary arteries
patheticvagus Parasympatheticterminate on SA nerves and AV nodes and coronary arteries,
Located inferior decreases heart rate and force ofto the aortic arch contraction, causes vasoconstrictionand anterior to of coronary arteriesthe right pulmo-nary artery
(continued)
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24 CLINICAL ANATOMY FOR YOUR POCKET
Nerves of the heart (continued)
Nerve Origin Structures InnervatedDeep cardiac Sympatheticplexus sympathetic
trunks Parasym-
patheticvagus nerves
Located posterior to the aortic arch and anterior to the tracheal bifurcation
Visceral Fibers travel with Fibers traveling with sympatheticsafferents of sympathetics and convey pain information to T1T5 cardiac plexuses in the vagus nerve spinal cord segments; these fibers are
involved in pain referred to the left upper limb during heart attack
Fibers traveling in the vagus nerve innervate baroreceptors and chemoreceptors that monitor pressureand gas concentrations in the blood
Sinuatrial (SA) Group of self- Pacemaker of the heart, gives an node excitable cardiac impulse ~70 times per minute
muscle cells located near the junction of the superior vena cava and the right atrium
Atrioventricular Located on the Receives impulse from wall of atria(AV) node right side of the that was initiated in the SA node
atrial septum near Passes impulse to ventricles via the the opening of the AV bundlecoronary sinus
AV bundle Fiber bundle pass- Only bridge of conduction system(Bundle of His) ing from the AV between atria and ventricles
node to membran-ous part of inter-ventricular septum, where it terminates by dividing into bundle branches
Right and left Formed by termina- Supply cardiac muscle cells ofbundle branches tion of AV bundle, ventricular walls through ramifications
follow interventri- (subendocardial branches)cular septum to Right bundle branch sends a branchventricular walls through the septomarginal trabeculaewhere they ramify of the right ventricle to the anterior
papillary muscle
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Additional ConceptPostsynaptic parasympathetic ganglia are located near theSA and AV nodes.
CHAPTER 1 | THORAX 25
Vessels of the heart
Artery Origin DescriptionRight coronary Right aortic Supplies right atrium & ventricle, left
sinus ventricle, SA and AV nodes, and inter-ventricular septum
SA nodal branch Right coronary Supplies SA nodeRight marginal artery Supplies right ventricle and apex of branch heartPosterior Supplies both ventricles and posterior interventricular aspect of interventricular septumAV nodal branch Supplies AV nodeLeft coronary Left aortic sinus Supplies left atrium and ventricle, right
ventricle, and interventricular septumAnterior interven- Left coronary Supplies right and left ventricles andtricular (left artery interventricular septumanterior descendingLeft circumflex Supplies left atrium and ventriclebranchLeft marginal Left circumflex Supplies left ventriclebranch branchPosterior interven- Left coronary Supplies interventricular septumtricular branch arteryVein Termination DescriptionCoronary sinus Right atrium Large vein on posterior aspect of heart
in coronary sulcus; accepts most venousblood from the heart before emptying into right atrium
Great cardiac Coronary sinus Runs with anterior interventricular artery in anterior interventricular sulcus;becomes coronary sinus on posterior aspect of heart
Middle cardiac Runs with posterior interventricular artery in posterior interventricular sulcus
Small cardiac Runs with right marginal branchOblique vein of Remnant of primordial left superior left atrium vena cavaLeft posterior Drains posterior aspect of left ventricleventricularLeft marginal Drains left margin of heartAnterior cardiac Right atrium Drains right ventricleSmallest cardiac Chambers of Drains walls of all 4 chambers of heart
heart
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Additional ConceptVenous DrainageVenous drainage of the heart is said to be indirect becausemost venous blood enters the coronary sinus before beingemptied into the right atrium.
Clinical SignificanceCoronary ArteriesCoronary artery disease is a leading cause of death, typicallyas a result of decreased blood flow to the heart. An area ofmyocardium that has undergone necrosis (as a result of lackof blood) constitutes a myocardial infarction or heart attack.
LUNGS AND PLEURA
26 CLINICAL ANATOMY FOR YOUR POCKET
Structure Description SignificanceEndothoracic Fibroareolar layer between Invests muscular and skeletalfascia parietal pleura and thoracic elements of thoracic wall and
wall adheres parietal pleura to inner surface of thoracic wall
Costal pleura Parietal pleura adherent to Intercostal and phrenic nervesthe inner surface of the ribs provide sensory innervation; and costal cartilages via the therefore, pain may be referred endothoracic fascia to the thoracic wall and neck
Mediastinal Parietal pleura adherent topleura the outer surface of the
mediastinum via the endothoracic fascia
Diaphragmatic Parietal pleura adherent topleura the superior surface of the
diaphragm via the endotho-racic fascia
Cervical pleura Parietal pleura extending into the root of the neck
Covered by the supra-pleural membranea regional thickening of the endothoracic fascia
Pulmonary Double-layered fold of pleura Area of reflectionvisceralligament extending inferiorly from the pleura from the surface of
root of the lung the lung is continuous with parietal pleura
Structure of the pleural cavities(Figures 1-4, 1-6 and 1-7)
(continued)
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CHAPTER 1 | THORAX 27
Structure Description Significance
Structure of the pleural cavities (continued)
Visceral pleura Covers all surfaces of each Continuous with parietal lung pleura at the root of the
lung No or very limited pain
afferents
Pleural cavity Potential space between the Contains capillary layer of visceral and parietal pleura serous fluid
Negative pressure here maintains lungs in inflated state
Left and right Potential space between During inspiration the lungscostodiaphrag- costal and diaphragmatic enter the recessesmatic recesses pleura
Left and right Potential spaces betweencostomediastinal costal and mediastinalrecess pleura
IVC andpericardium
Pericardium
Left ventricle
Pulmonary trunk
Right atrium
Superiorvena cava
FIGURE 1-6. Anteroposterior chest radiograph. Radiographshows the various components of the heart and great vessels. (FromDudek RW, Louis TM. High-Yield Gross Anatomy. 3rd ed. Baltimore:Lippincott Williams & Wilkins; 2008:85.)
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Clinical SignificanceCervical PleuraThe cervical pleura and apex of the lung are subject toinjury from neck wounds because the pleural cavity extendsinto the root of the neck.
28 CLINICAL ANATOMY FOR YOUR POCKET
FIGURE 1-7. Pneumothorax. A pneumothorax is air in the pluralcavity; this has the effect of collapsing the elastic lung as the negativepressure maintaining it in its expanded state is lost. Posteroanteriorradiograph shows a left apical (straight arrows) and subpulmonic(curved arrow) pneumothorax in a 41-year-old woman with respira-tory distress syndrome. (From Dudek RW, Louis TM. High-YieldGross Anatomy. 3rd ed. Baltimore: Lippincott Williams & Wilkins;2008:64.)
Structure Description Significance
Tracheal rings 20 U-shaped hyaline Keep trachea patentcartilages Posteriorly oriented opening
of U-shaped cartilage allowsfor expansion of the esoph-agus during swallowing
Tracheobronchial tree(Figure 1-4)
(continued)
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CHAPTER 1 | THORAX 29
Structure Description Significance
Tracheobronchial tree (continued)
Trachealis Layer of smooth muscle Spans posterior deficiency of tracheal rings
Right and left Extend from tracheal bifur- Form part of root of the lungmain bronchi cation to hilum of lungs Enter lung at hilum
Supported by U-shaped Right main bronchus is shor-hyaline cartilage ter, wider and more vertically
Terminate by dividing into oriented than the leftlobar bronchi Hyaline cartilage keeps both
main bronchi patent
Carina Keel-like septum projecting Visible on radiographs; superiorly at the bifurcation displacement may indicate of the trachea thoracic pathology
Lobar (secondary) Supported by hyaline Hyaline cartilage keeps bronchi (3; right) cartilage lobar bronchi patent
Lobar (secondary) Extend from main bronchi Each lobar bronchusbronchi (2; left) until termination as seg- corresponds to a lobe
mental bronchi of the lung
Segmental Supported by hyaline Supply bronchopulmonary (tertiary) bronchi cartilage segmentsright lung: 10
Formed from terminal segmental bronchibranches of lobar bronchi Left lung: 810 segmental
bronchi
Bronchopulmo- Pyramidal-shaped with Each receives a segmental nary segments apex directed toward root of bronchus and a branch of
lung and base toward outer both pulmonary andsurface of lung bronchial arteries
Intersegmental veins help identify boundaries between segments for resection
Additional ConceptBronchopulmonary Segments
Right lungSuperior lobe: Apical, Posterior, AnteriorMiddle lobe: Lateral, MedialInferior lobe: Superior, Anterior basal, Posterior basal,Lateral basal, Medial basal
Left lungSuperior lobe: Superior divisionApicoposterior,Anterior; Lingular divisionSuperior, Inferior
Inferior lobe: superior, Anterior basal, posterior basal,Lateral basal, Medial basal
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Structure Description Significance
Right lung 3 lobes (superior, middle, The right lung is larger than and inferior) separated by the lefta horizontal and oblique fissure
Left lung 2 lobes (superior and inferior) The left lung is smaller thanseparated by an oblique the right owing to the positionfissure of the heart
Cardiac notch Indentation of superior lobe Result of the heart and of left lung along the pericardial sac bulging to theanteroinferior border left
Lingula Tongue-like process of superior lobe of the left lung inferior to the cardiac notch
Root of lung Formed by pulmonary and Located on medial aspect of bronchial arteries, pulmo- lung, site at which structuresnary and bronchial veins, enter and leave the lunglymphatics, nerves, and main bronchi
Enclosed by pleural sleeve
Hilum of lung Located on medial aspect of Root of lung enters lung herelungs
Horizontal and Right lung has 1 horizontal Separate lungs into lobes:oblique fissures and 1 oblique fissure right lung 3, left lung 2
Left lung has 1 oblique fissure
MnemonicInhale a Bite, Goes Down the Right Inhaled objects more likely to enter right bronchus, as it iswider, shorter, and more vertical than the left.
Structure of the lungsThe lungs are the elastic organs of respiration. Their function depends upon surface tension in the pleural cavity keeping the parietal and visceral layers of pleuratogether.
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Additional ConceptPostsynaptic parasympathetic ganglia are found distributedthroughout both plexuses.
CHAPTER 1 | THORAX 31
Nerves of the lungs
Nerve Origin Structures Innervated
Anterior Sympathetic Sympatheticinhibit bronchialpulmonary plexus sympathetic smooth muscle (bronchodilate) and
trunks glands, motor to vessels Parasym- (vasoconstrict)
patheticvagus Parasympatheticinhibit vessel nerves musculature (vasodilate), motor to
Located anterior smooth muscle of bronchial tree to root of lung (bronchoconstrict) and glands
(stimulates mucous secretion)
Vessels of the lungs
Artery Origin Description
Right and left Pulmonary Give rise to lobar arteries; carrypulmonary trunk deoxygenated blood to the lungs
Lobar Pulmonary 3 right and 2 left lobar arteries carry arteries deoxygenated blood to each lobe of the
lung; accompany secondary bronchi
Right and left Right Supply oxygenated blood to the tissuesbronchial posterior of the bronchial tree
intercostal artery
Leftthoracic aorta
Vein Termination DescriptionRight and left Left atrium 2 pairs of pulmonary veins convey pulmonary oxygenated blood to the left atrium
(continued)
Posterior Sympatheticpulmonary plexus sympathetic
trunks Parasym-
patheticvagus nerves
Located posterior to root of lung
Visceral afferents Fibers travel in Sensory to tissues of the lungs andof pulmonary vagus nerve bronchitouch, stretch, temperature,plexuses and chemical irritants
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Additional ConceptThe superficial and deep lymphatic plexuses of the lungscommunicate freely.
Clinical SignificanceBronchopulmonary nodes are an early site of tumormetastases in bronchogenic carcinoma.
Additional ConceptLigamentum ArteriosumThe ligamentum arteriosum is the remnant of the ductusarteriosusan embryologic shunt connecting the arch ofthe aorta and the left pulmonary artery.
32 CLINICAL ANATOMY FOR YOUR POCKET
Lymphatic structure Description Drainage
Superficial Located immediately deep to Drains to bronchopulmonary lymphatic plexus visceral pleura lymph nodes
Deep lymphatic Located in the submucosa of Drains to pulmonary lymph plexus bronchi and connective nodes
tissue around the bronchi
Pulmonary Located along the lobar Drain to bronchopulmonary lymph nodes (secondary) bronchi lymph nodes
Bronchopul- Located in the hilum of the Drain to tracheobronchialmonary (hilar) lung(s) lymph nodeslymph nodes
Superior and Located at the bifurcation of Drain to bronchomediastinal inferior tracheo- the trachea trunks (right and left)bronchial lymph nodes
Lymphatics of the lungs
Vessels of the lungs (continued)
Vein Termination Description
Right and left Right Drain deoxygenated blood from the bronchial azygos vein bronchial tree
Leftaccessory hemiazygos vein
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INTRODUCTIONThe abdomen is that portion of the trunk inferior to thediaphragm and superior to the pelvis with which it is con-tinuous. The abdomen extends inferiorly to the superiorpelvic aperture.
AREAS AND FASCIA OF THE ABDOMEN
2Abdomen
33
Area Structure SignificanceAbdominal cavity
Regions (9)
Areas of the abdomen
Boundaries: Superior
diaphragm Inferior
continuous withpelvic cavity atsuperior pelvicaperture
Anterolateralmuscular abdominalwall
Posteriorvertebral column
Divided into regionsby: 2 horizontal
planessubcostaland transtubercular
2 vertical-midclavicularplanes
Larger, superior part of theabdominopelvic cavity
Regions: Right and left
hypochondriac Right and left inguinal Right and left lateral Epigastric Umbilical Pubic
Used for description oforgan location or locationof pathologic processes
(continued)
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Area Structure SignificanceQuadrants (4)
Inguinal canal
Subinguinal space
Areas of the abdomen (continued)
Divided intoquadrants by ahorizontal(transumbilical) and avertical (median)plane 46 cm long,
inferomediallydirected passageextending betweenthe deep andsuperficial inguinalrings
Walls of canal: Anterior
external obliqueaponeurosis
Posteriortransversalisfascia andmedially theconjoint tendon
Rooftransversalisfascia and archingfibers of theinternal obliqueand transversusabdominis
Flooriliopubictract, inguinalligament, andlacunar ligamentfrom lateral tomedial
Space located deep tothe inguinal ligamentand iliopubic tract
Quadrants: Right and left upper Right and left lower
Used for description oforgan location or locationof pathologic processes
Transmits the spermaticcord or round ligament ofthe uterus, ilioinguinalnerve, and the genitalbranch of thegenitofemoral nerve
One result of the obliquenature of canal is that thesuperficial and deep ringsdo not overlap; therefore,increases in intra-abdominal pressure forcethe canal closed toprevent herniation
Serves to connect theabdominopelvic cavity withthe lower limb
Additional ConceptsDeep Inguinal RingThe deep inguinal ring, the internal opening of the inguinalcanal, is an evagination of transversalis fascia, just superiorto the middle of the inguinal ligament and immediately lat-eral to the inferior epigastric vessels.
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Superficial Inguinal RingThe superficial inguinal ring is the slitlike external open-ing of the inguinal canal in the aponeurosis of the externaloblique muscle, just superior to the public tubercle. Themedial and lateral margins of the opening are the medialand lateral crura, which are prevented from spreadingapart by intercrural fibers.
CHAPTER 2 | ABDOMEN 35
Feature DescriptionSuperficial fascia
Investing fascia
Endoabdominal fascia
Parietal peritoneum
Rectus sheath
Structures of the abdominal wall
Inferior to umbilicus, it is composed of 2 layers: A superficial fatty layer (Campers fascia) A deep membranous layer (Scarpas fascia)
Covers the muscles (4) forming the muscular wall ofthe abdomen Lines inner surface of abdominal wall Named according to muscle it lines:
Transversalis fascia lines the transverseabdominal muscle Divided into anterior, middle, and posterior
layers Middle and posterior layers enclose the
intrinsic muscles of the backrelativelythick, provides attachment for anterolateralabdominal wall muscles
Anterior layer is fascia of quadratuslumborum musclethickened superiorly toform lateral arcuate ligament, inferiorlyattaches to iliolumbar ligament
Lumbar fascia lines the quadratus lumborum Psoas fascia lines the psoas major muscle
It is thickened superiorly to form the medialarcuate ligament
It is continuous with the thoracolumbarfascia
Lines abdominopelvic cavity Located deep to the endoabdominal fascia
from which it is separated by extraperitoneal fat
Formed by the aponeuroses of the external andinternal oblique and transverse abdominal
The sheath contains the rectus abdominis, the superior and inferior epigastric vessels, the pyramidalis, segmental nerves, andlymphatics
(continued)
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Additional ConceptRectus SheathRectus sheathAbove a line midway between thepubic symphysis and umbilicus the anterior layer of thesheath is formed by the external oblique and the ante-rior portion of the internal oblique, which splits to con-tribute to the posterior layer of the sheath with thetransverse abdominal muscle. Below this line, thesheath is deficient posteriorly, with the aponeurosis ofall three muscles forming the anterior layer of thesheath, with only the transversalis fascia separating therectus abdominis from the parietal peritoneum. Thelower edge of the aponeurotic line of the posteriorsheath is the arcuate line.
36 CLINICAL ANATOMY FOR YOUR POCKET
Feature Description
Conjoint tendon
Inguinal ligament
Iliopubic tract
Lacunar ligament
Pectineal ligament
Structures of the abdominal wall (continued)
Fused tendons of internal oblique and transverseabdominal at their attachment to the pubis
Forms medial portion of posterior wall of inguinalcanal
Free, fibrous inferior edge of external oblique,extending between the anterior superior iliacspine and pubic tubercle
Laterally provides attachment for transverseabdominal and internal oblique
Thickened inferior margin of the transversalisfascia
Forms portion of floor and posterior wall ofinguinal canal
Located posterior and parallel to the inguinalligament
Forms the anterior boundary of the subinguinalspace
Medial-most internally directed portion of theinguinal ligament
Forms portion of floor of inguinal canal Attaches to superior pubic ramus
Continuation of lacunar ligament as it runs alongthe pectin pubis
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CHAPTER 2 | ABDOMEN 37
Proximal Distal Muscle Attachment Attachment Innervation Main ActionsAnterolateral Abdominal WallExternal oblique
Internal oblique
Transverse abdominal
Rectus abdominis
Pyramidalis
Spermatic Cord and ScrotumCremaster
Dartos
Posterior Abdominal WallPsoas minor
Muscles of the abdominal wall
Ribs 512
Thoracolumbarfascia,anterior iliaccrest, inguinalligamentCostalcartilages712,thoracolumbarfascia, iliaccrest, inguinalligamentPubicsymphysis andpubic crest
Pubis
T12L1vertebrae andintervertebraldiscs
Linea alba,pubic crestandtubercle,anterior iliaccrest
Ribs 1012,linea alba,pectin pubis(via conjointtendon)Linea alba,pubic crest,pectin pubis(via conjointtendon)
Xiphoidprocess,costalcartilages57
Linea alba
Pectin pubis
T5T12
T6T12 andL1
T6T12
T12
Genitofemo-ralAutonomic
L1
Compress,protect, andsupportabdominalcontents; flexand rotatetrunkCompress,protect, andsupportabdominalcontents
Compress,protect, andsupportabdominalcontents; flextrunk (lumbarregion)Tenses lineaalba
Draws testescloser to bodyWrinkles skinof scrotum
Weak trunkflexor; oftenabsent
Found within cremaster fascia
Found within superficialfascia of scrotum
ABDOMINAL WALL
(continued)
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38 CLINICAL ANATOMY FOR YOUR POCKET
Skeletal elements (attachments) discussed above are presentedwith the thorax and pelvis.
Clinical SignificanceGuarding ReflexIn addition to the functions mentioned previously, the flatabdominal wall muscles provide protection to abdominalviscera through involuntary contraction when touched orwhen an underlying structure is inflamed, becoming rigid;this is known as the guarding reflex.
MnemonicsOrientationHands-in-your-pockets orientation:
When you put your hands in your pants pockets, your fin-gers have the orientation of fibers of the externaloblique inferomedially.
Internal oblique fibers are at right angles to externaloblique fibers.
Psoas MajorInnervation of psoas major: Hitting L2, L3, and L4 makesthe psoas sore.
Vessels of the abdominal wall
Artery Origin DescriptionMusculophrenic Internal thoracic Supplies: diaphragm, anterolateral Superior epigastric abdominal wall
Inferior epigastric External iliac Supplies: rectus abdominis, antero-lateral abdominal wall
(continued)
Proximal Distal Muscle Attachment Attachment Innervation Main ActionsPsoas major
IliacusQuadratus lumborum
Muscles of the abdominal wall (continued)
T12L5vertebrae andintervertebraldiscsIliac fossa12th rib
Lessertrochanterof femur
Iliolumbarligament andiliac crest
L2L4
FemoralT12L4
Together formiliopsoasthechief flexor ofthe thigh
Extends andlaterally rotatesvertebral column
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Additional ConceptAbdominal AortaThe abdominal aorta is the continuation of the thoracic aortaafter it passes through the aortic hiatus of the diaphragm.Theabdominal aorta terminates by dividing into common iliacarteries at L4 vertebral level.The abdominal aorta gives:
paired visceral branches: suprarenal, renal, and gonadal unpaired visceral branches: celiac trunk, superior mesen-
teric and inferior mesenteric arteries paired parietal: inferior phrenic and lumbar unpaired parietal: median sacral artery.
Venous DrainageVeins generally parallel arteries and drain into the inferiorvena cava, with the notable exception of the portal system,which drains to the liver.
CHAPTER 2 | ABDOMEN 39
Vessels of the abdominal wall (continued)
Artery Origin DescriptionSuperficial Femoral Supplies: region between umbilicusepigastric and pubisSuperficial circum- Supplies: inguinal region and flex iliac anterosuperior thighDeep circumflex External iliac Supplies: iliacus and anterolateraliliac abdominal wallSubcostal Thoracic aorta Supplies: anterolateral abdominal wallLumbar Abdominal aorta Supplies: back and posterior (45 pairs) abdominal wallTesticular Supplies: testes and epididymisArtery of the Inferior vesical Supplies: ductus deferensductus deferens arteryCremasteric Inferior epigastric Supplies: cremaster muscle and
artery fasciaVein Termination DescriptionPampiniform Plexus converges Drains the spermatic cord and testesplexus to form the
testicular veins
Nerves of the abdominal wall
Nerve Origin Structures InnervatedThoracoabdominals T7T11 Anterolateral abdominal wall superior Subcostal T12 to iliac crest
(continued)
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MnemonicLumbar PlexusLumbar plexus nerve roots: 2 from 1, 2 from 2, 2 from 3:
2 nerves from 1 root: ilioinguinal (L1), iliohypogastric (L1).2 nerves from 2 roots: genitofemoral (L1L2), lateral cuta-
neous nerve of the thigh (L2L3). 2 nerves from 3roots: obturator (L2L4), femoral (L2L4).
40 CLINICAL ANATOMY FOR YOUR POCKET
Feature Description SignificanceWall Double layered: skin and Outpouching of lower
superficial fascia (dartos): anterior abdominal wallcontains smooth muscle Dartos muscle receives fibersdartos muscle autonomic innervation and
functions to wrinkle the skinArterial SupplyPosterior scrotal Origin: perineal artery Supplies posterior aspectbranchesAnterior scrotal Origin: external pudendal Supplies anterior aspectbranches arteryCremaster Origin: inferior epigastric Supplies the superior aspectartery artery
Structure of the scrotum
Nerves of the abdominal wall (continued)
Nerve Origin Structures Innervated
Lumbar PlexusIliohypogastric L1 Anterolateral abdominal wall of
inguinal and hypogastric regionsIlioinguinal Scrotum/labia majorum, mons pubis,
medial thigh, and lower-most aspect of anterolateral abdominal wall
Genitofemoral L1, L2 Divides into genital and femoral branches;genital branch supplies cremaster and cutaneous innervation to anterior aspectof scrotum; femoral branch is sensoryto anteromedial aspect of thigh
Lateral cutaneous L2, L3 Supplies sensory innervation to nerve of the thigh anterolateral aspect of thighObturator L2L4 Supplies adductor compartment of thighFemoral Supplies hip flexors and knee extensorsLumbosacral trunk L4, L5 Participates in formation of sacral
plexus (L4S4)
(continued)
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The testes and epididymis are presented with the reproductiveorgans in the pelvis and perineum chapter.
Clinical SignificanceSensory Innervation of the ScrotumAs the anterior aspect of the scrotum is supplied bybranches of the ilioinguinal nerve and the posterior aspectby the branches of the perineal and posterior femoral cuta-neous nerves, care must be taken to properly anesthetize thescrotum for surgical procedures.
Structure of the spermatic cordThe spermatic cord runs through the inguinal canal into thescrotum.The cord contains structures coursing between thescrotum and the abdominopelvic cavity.
CHAPTER 2 | ABDOMEN 41
Feature Description SignificanceNerve Supply
Genital branch Origin: genitofemoral nerve Supplies anterolateral of genitofemoral (L1L2) surfacenerve
Anterior scrotal Origin: ilioinguinal nerve Supplies anterior surfacenerves (L1)
Posterior scrotal Origin: perineal branches of Supplies posterior surfacenerves pudendal nerve (S1S4)
Perineal Origin: posterior femoral Supplies inferior surfacebranches of cutaneous nerve (S2S3)posterior femoralcutaneous
Structure of the scrotum (continued)
Structure Description Significance
Fascial coverings Internalinternal Internal spermaticof spermatic spermatic fascia derived from transversalis cord Middlecremaster fascia fascia
Externalexternal Cremasterderivedspermatic fascia from internal oblique
External spermaticderived from external oblique
(continued)
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Clinical SignificanceTemperature RegulationThe cremaster muscle (skeletal muscle), found with thecremaster fascia, draws the testes toward the body in coldtemperatures as part of the cremasteric reflex. The dartosmuscle (smooth muscle) causes wrinkling of the scrotum todraw the testes nearer the body and reduce the surface areaof the scrotum in cold temperatures.
PERITONEAL CAVITY
42 CLINICAL ANATOMY FOR YOUR POCKET
Structure of the peritoneal cavity(Figure 2-1)
The peritoneal cavity is a potential, fluid-filled spacebetween adjacent layers of peritoneum in the abdomen. It isdivided into a lesser and a greater sac that correspond totheir embryologic origins as the right and left halves of theintraembryonic cavity.
Structure Description SignificanceComponentsDuctus deferens Tube composed of smooth Conveys sperm from the
muscle epididymis to the ejaculatory duct
Testicular artery Arises from abdominal aorta Supplies testes andepididymis
Artery of the Arises from inferior vesical Supplies ductus deferensductus deferens arteryCremasteric Arises from inferior Supplies cremaster muscle artery epigastric artery and fasciaPampiniform Venous plexus that drains the Converges to form the plexus of veins testes and spermatic cord testicular veinsAutonomics Sympathetic and Innervates dartos and
parasympathetic nerve vessels of regionnetwork Responsible for peristaltic
contractions during emission
Genital branch Origin: L1L2; divides into Supplies cremaster muscleof genitofemoral genital and femoral
branches
Structure of the spermatic cord (continued)
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CHAPTER 2 | ABDOMEN 43
Bounded by: Anteriorliver,
stomach and lesseromentum
Posteriordiaphragm Rightliver Leftgastrosplenic
and gastrorenalligaments
Limited by diaphragm andposterior leaf of coronaryligament of the liverLimited by fusion ofanterior and posteriorleafs of greater omentumAll of the peritonealcavity that is not thelesser sac
Located posterior to theportal triad and anteriorto the inferior vena cavaDepressions runningparallel with theascending anddescending colon alongthe posterior abdominalwallFormed by the mesenteryof the transverse colonthe transverse mesocolon
Superior extensions of theperitoneal cavity betweenthe diaphragm and liverExtension of peritonealcavity inferior to the liverand anterior to the kidneyand suprarenal gland
Smaller portion of theperitoneal cavity
Formed by embryologicrotation of the gut
Superior extent of thelesser sac
Inferior extent of thelesser sac
Larger portion of theperitoneal cavity
Formed by embryologicrotation of the gut
Connection between thelesser and greater sac
Function as channelsthat convey peritonealfluid
Communicationbetween supra- andinfracolic compartments
Part of the peritonealcavity superior to thetransverse mesocolonPart of the peritonealcavity inferior to thetransverse mesocolonSeparated into right andleft by the falciformligament Communicates
anteriorly with the rightsubphrenic space
Communicates withomental bursa (lessersac)fluid may draininto recess from herewhen supine
Structure of the peritoneal cavity (continued)
Feature Description SignificanceLesser sac (omental bursa)
Superior recess of lesser sac
Inferior recess of lesser sac
Greater sac
Omental foramen
Paracolic gutters
Supracolic compartment
Infracolic compartment
Subphrenic spaces
Hepatorenal recess
(continued)
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44 CLINICAL ANATOMY FOR YOUR POCKET
Feature Description SignificancePeritoneal FossaeSupravesical fossaeMedial inguinal fossae (related to inguinal triangles)Lateral inguinal fossae
Between the median andmedial umbilical foldsBetween the medial andlateral umbilical folds
Lateral to the lateralumbilical folds
Potential site for a hernia
Potential site for a directinguinal hernia
Deep inguinal rings foundwithin fossae, potentialsite for indirectinguinal hernia
Peritoneal pouches are presented with the pelvis.
Clinical SignificancePeritoneal PunctureOccasionally it is necessary to puncture the peritoneum toremove excess fluid (ascites) that accumulates duringinflammation, to conduct peritoneal dialysis or administeranesthetic agents through intraperitoneal injection.
Peritoneum (Figure 2-1)
Structure Description SignificanceParietal peritoneumVisceral peritoneumMesentery
Peritoneal FoldsMedian umbilical fold
Medial umbilical folds (2)
Serous membrane liningthe peritoneal cavity
Double layer ofperitoneum connectingintraperitoneal organs tothe abdominal wall
Conveys neurovascularelements and lymphatics
Allows movement of theorgan to which it isattached
Fold of parietal peritoneumextending from the apex ofthe bladder to the umbilicusFold of parietal peritoneumfound lateral to the medianumbilical fold
Lines internal surface ofabdominal wallLines external surfaces ofabdominal organs The mesentery refers
specifically to the mes-entery of the small intestine
Other mesenteries arenamed specifically for theorgans to which they areassociated (e.g., transversemesocolon ormesoappendix)
Covers the medianumbilical ligamenttheremnant of the urachusCovers the medial umbilicalligamentsthe obliteratedpart of the umbilical arteries
(continued)
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CHAPTER 2 | ABDOMEN 45
Peritoneum (continued)
Fold of parietal peritoneumfound lateral to the medialumbilical folds
Double layer of peritoneumconnecting greater curvatureof stomach and proximalduodenum to adjacent organs
Double layer ofperitoneum connectinglesser curvature of thestomach and proximalduodenum to adjacentorgans
Forms anterior wall oflesser sac
Double layer ofperitoneum extendingfrom umbilicus to liver onanterior abdominal wall
Continuous superiorly asleft and right coronaryligament
Anterior formed byseparation of leafs offalciform ligament
Posterior is formed ofperitoneal reflexion fromdiaphragm to liver
Formed of anterior andposterior coronaryligaments
Connective tissue cord ininferior border of falciformligament
Covers the inferiorepigastric vessels
3 parts: 1. Gastrophrenic
ligamentconnectsstomach to diaphragm
2. Gastrosplenicligamentconnectsstomach to spleen
3. Gastrocolic ligamentconnects stomach totransverse colon, largestpart, anterior and posteriorlayers are fused to form a4-layered structure
2 parts:1. Hepatogastric
ligamentconnectsstomach to liver
2. Hepatoduodenalligamentconnectsduodenum to liver, containsportal triad: portal vein,hepatic artery and bile duct
Embryologic remnant ofthe ventral mesentery
Contains round ligament ofthe liver in its inferior,crescentic border
Bound the bare area of theliver
Formed of a peritonealreflexion between anteriorand posterior leafs ofcoronary ligamentsEmbryologic remnant of theumbilical vein
Structure Description SignificanceLateral umbilical folds (2)
OmentaGreater
Lesser
Associated with the LiverFalciform ligament
Coronary ligaments (anterior and posterior)
Triangular ligaments (right and left)
Round ligament of liver
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Liver
Lesser omentum
Pancreas
Falciformligament
Stomach
Duodenum
Transversemesocolon
Transverse colon
Mesentery ofsmall intestine
Greater omentum
Jejunum
Ileum
Visceral peritoneum
Parietal peritoneum
Rectovesical pouch
Urinary bladder
Rectum
Superior recess of omental bursa
Inferior recess of omental bursa
Transversemesocolon
Left colicflexure
A Right lateral view
B Anterior view
Transversecolon
Right colicflexure
Supracoliccompartment
Ascendingcolon
Tenia coli
Descendingcolon
Root ofmesentery ofsmall intestine
Leftparacolicgutter
Leftinfracolicspace
Rightparacolicgutter
Rightinfracolicspace
Phrenicocolicligament
Infracolic compartment
Subhepaticspace
Supracoliccompartment(greater sac)
Omentalbursa(lesser sac)Infracoliccompartment(greater sac)
FIGURE 2-1. Subdivisions of peritoneal cavity. A: This mediansection of the abdominopelvic cavity shows the subdivisions of theperitoneal cavity. B: The supracolic and infracolic compartments ofthe greater sac are shown after removal of the greater omentum.Theinfracolic spaces and paracolic gutters determine the flow of asciticfluid when inclined or upright. (From Moore KL, Dalley AF.Clinically Oriented Anatomy. 5th ed. Baltimore: Lippincott Williams& Wilkins; 2006:239.)46
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Additional ConceptsPeritoneal RelationsOrgans that are suspended by a mesentery are said to beintraperitoneal. Organs that lack a mesentery and are onlypartially covered with peritoneum are said to be extraperi-toneal (retroperitoneal or subperitoneal provides more indi-cation of their location).
Median Umbilical LigamentThe median umbilical ligament is formed by the urachus,the obliterated portion of the allantois, connecting the apexof the bladder with the umbilicus.
Medial Umbilical LigamentsThe medial umbilical ligaments are formed by the oblit-erated portions of the umbilical arteries distal to the supe-rior vesical arteries.
Clinical SignificanceHerniaeA direct inguinal hernia (acquired) exits the abdomen viathe medial inguinal fossa or inguinal triangle, which isbounded medially by the semilunar line (lateral border ofrectus abdominis), laterally by the lateral umbilical folds andinferiorly by the inguinal ligament.
An indirect inguinal hernia (congenital) exits theabdomen via the deep inguinal ring and passes through theinguinal canal into the scrotum.
AdhesionsAdhesions may develop in the peritoneal cavity as a result ofinflammation of the peritoneum (peritonitis) or previoussurgery, which may need to be removed if they compromisethe function of the viscera.
MnemonicStructures forming folds: IOU:From lateral to medial:
lateral umbilical ligament: Inferior epigastric vesselsmedial umbilical ligament: Obliterated umbilical arterymedian umbilical ligament: Urachus
CHAPTER 2 | ABDOMEN 47
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ESOPHAGUS
48 CLINICAL ANATOMY FOR YOUR POCKET
Feature Description SignificanceSphincters
Innervation
Arterial supply
Venous drainage
Structure of the esophagusThe esophagus is a muscular tube extending from the cricoidcartilage to the gastroesophageal junction; it enters theabdomen through the esophageal hiatus of the diaphragm.The nature of the musculature of the esophagus changesthroughout its course:
upper thirdskeletal muscle middle thirdmixture of smooth and skeletal muscle lower thirdsmooth muscle
2 sphincters: 1. Upper esophageal
sphincterskeletalmuscle
2. Lower esophagealsphinctersmoothmuscle and skeletalmuscle of diaphragm
Skeletal muscle partrecurrent branches ofthe vagus nerve
Smooth muscle partesophageal plexus
Inferior thyroid,esophageal, bronchial,left gastric and leftinferior phrenic arteriesEsophageal veins emptyinto the inferior thyroid,azygos, hemiazygos andgastric veins
Upper sphinctercomposed mainly ofcricopharyngeus
Lower sphinctersmooth muscle andmuscular diaphragmaticesophageal hiatusprevent gastroe-sophageal reflux
Esophageal plexusparasympathetic fibersfrom the vagus nerves andsympathetic fibers fromsympathetic chain andgreater splanchnic nerveArterial supply is generallyvia whatever arteries lienear this long longitudi-nally oriented structureImportant contributor tothe portal-cavalanastomosis
Clinical SignificanceEsophageal VaricesEsophageal varices are dilated esophageal veins that mayrupture in cases of portal hypertension.
PyrosisPyrosis (heartburn) is usually the result of regurgitation ofstomach contents into the lower esophagus.
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STOMACH
CHAPTER 2 | ABDOMEN 49
Structure of the stomach(Figure 2-3)
The stomach is the muscular organ of digestion; it produceschyme through enzymatic digestion.
Part surrounding cardialorifice
Part superior to cardialorificePart between fundus andpyloric antrum Distal-most part of the
stomach Possesses smooth
muscle sphincterpyloric sphincter,which guards thepyloric orifice thatopens into theduodenum
Funnel-shaped Divided into the
pyloric antrum (wide)and pyloric canal(narrow)
Directed inferior and tothe leftDirected superior and tothe right
Longitudinal folds ofgastric mucosa
Cardial orificefunnel-shaped opening ofstomach that receives theesophagusTypically dilated and gas-filledMajor part of thestomachPyloric sphincter controlsrelease of gastriccontents into theduodenum and preventsreflux from duodenuminto stomach
Longer, convex curvature
Shorter, concavecurvature
Bears the angularincisureouterrepresentation of thejunction of the bodyand pyloric part
Function to increasesurface area and allowfor distension
Feature Description SignificancePartsCardia
Fundus
Body
Pylorus
CurvaturesGreater
Lesser
InteriorRugae (gastric folds)
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Clinical SignificancePylorospasmPylorospasm is the failure of the pyloric sphincter torelax, which prevents food from passing from the stomachto the duodenum, often occurs in infants and may resultin vomiting.
50 CLINICAL ANATOMY FOR YOUR POCKET
Vessels of the stomach (Figure 2-4)
Supplies embryologicforegut
Gives rise to: splenic,hepatic and left gastricarteries
Supplies the spleen Gives rise to left gastro-
omental and short gastricarteries to the stomach
Supplies the liver Gives rise to gastroduodenal
and right ga