Skeletal imaging, atlas of the spine and extremities 2nd ed j taylor, t hughes, d resnick (saunders, 2010) 1

Entity General Characteristics General Imaging FindingsAchondroplasia Relatively common rhizomelic dwarfi sm Accentuated lumbar lordosis, waddling gait, prominent forehead, depressed nasa

SKELETAL IMAGING: ATLAS OF THE SPINE AND EXTREMITIES, ISBN 978-1-4160-5623-2

SECOND EDITION

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this book It is the responsibility of the treating practitioner, relying on independent expertise and

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to my students who provide continuous motivation;

and to my co-authors, Tudor Hughes and Donald Resnick.

JAMT

To my coauthor, John, who is clearly the fi rst author.

And to my always-supportive family: my loving wife Kelly;

my three wonderful boys, Geraint, Griffi th, and Rhett;

and my learned parents, Dorothy and Fred.

THH

It was a great pleasure and a distinct honor for me to work with two

skilled colleagues and friends, John Taylor and Tudor Hughes,

whose efforts far overshadow my contributions to this text.

They brought organization, dedication, and enthusiasm to

the project, sprinkled with good old-fashioned energy.

DR

BACKGROUND

We initially intended the Second Edition of Skeletal

Imaging to be merely a modifi cation of the First Edition

We planned only on updating the original and adding

new case material that illustrates the more recent

advances in the imaging diagnosis of musculoskeletal

disorders After all, only 9 years had elapsed between

publication of the fi rst edition, and the beginning of

research for this edition However, our survey of the

literature published since 2000 persuaded us that a

wealth of new information deserved synthesis and

recognition Our major dilemma was not so much to

decide what to include, but what to exclude, and still

meet our two principal objectives—to limit the atlas to

a single volume and to address the most important

mus-culoskeletal disorders Accordingly, we have focused on

disorders most frequently encountered in practice and on

how those disorders appear on conventional

radiogra-phy, CT scans, MR images, and to a lesser extent,

radio-nuclide imaging and diagnostic ultrasonography.

WHO WILL BENEFIT FROM THIS BOOK?

Radiologists, chiropractors, and other clinicians who

routinely interpret images of the musculoskeletal system

will fi nd the second edition an indispensable everyday

reference Radiology residents, chiropractic students,

and other clinicians-in-training who are preparing for

certifi cation examinations can use it in the classroom, at

the viewbox or monitor, and as a helpful study guide.

ORGANIZATION

The second edition retains the same organizational

strat-egy: arranging musculoskeletal disorders according to

anatomic region This organization enhances the book’s

value as a reference tool for practitioners and is a

practi-cal way for students to learn a logipracti-cal and methodipracti-cal

approach to patient assessment Each chapter includes a

description of the appearance of normal developmental

anatomy and major anomalies and anatomic variants It

also demonstrates the full range of the most frequently

encountered pathologic conditions, including dysplasias,

physical injuries, internal derangements of joints,

articu-lar disorders, and bone tumors, as well as metabolic,

hematologic, and infectious diseases.

Specifi cally, Chapter 1, “Introduction to Skeletal

Dis-orders: General Concepts,” consists of 19 tables

sum-marizing the general characteristics of the most common

disorders discussed and illustrated throughout the text

These tables offer an overview of information, such as

age of onset, sites of involvement, clinical features, and general imaging features This chapter was developed to avoid repetition of background material about disorders that affect several anatomic regions Chapters 2 to 17 represent stand-alone monographs, each dealing with a specifi c anatomic site The tables in these chapters emphasize only the site-specifi c manifestations of each entity, and they provide a sense of the range of disorders that characteristically affect that site Furthermore, in each of these regional chapters, most of the important conditions are illustrated with routine radiographs, some

of which are supplemented with conventional grams, CT or bone scans, MR images, or combinations

tomo-of these In addition, the chapters dealing with spinal regions and joints contain tables and illustrations of the normal developmental anatomy of that region through infancy, childhood, and adolescence When reading these chapters, it may be useful, or even necessary, to refer to Chapter 1 for a more detailed discussion of the general features of a particular disorder.

The major emphasis of this work, however, is on the illustrations that the authors believe represent the most characteristic or typical presentations of disease entities For the most part, the cases include commonly encoun- tered disorders, although some disorders that are seen less commonly also are included because they are impor- tant to consider with regard to differential diagnosis Purposely, the illustrations are as large as possible to best display the imaging fi ndings Each is accompanied by a detailed legend beginning with the primary diagnosis followed by a discussion of the imaging fi ndings and any available and important clinical data When MR imaging

is displayed, detailed imaging parameters are included in the legend.

At least one useful reference for each condition has been included The references are cited not only in the tables but also in the fi gure legends These reference cita- tions indicate the major sources of material and serve to direct the reader to further discussion In Chapter 1, a bibliography of recommended readings includes many textbooks dealing with various aspects of skeletal radiol- ogy that served as sources for information.

It is our hope that by retaining the successful features and format of the First Edition, updating the text to refl ect new information, and adding more case material that this edition will be as favorably received by readers and reviewers.

John A M Taylor Tudor H Hughes Donald Resnick

For the Second Edition

Many colleagues and friends who generously

contrib-uted so much to the fi rst edition have done so again, in

a variety of ways, for this revised second edition of

Skeletal Imaging We are enormously indebted to Dr

Brian Howard for contributing many more excellent case

studies from his teaching fi les; to Stephanie Brown, DC,

for compiling research material in the formative stages

of revision; and to Gary Smith, DC, DACBR, Matthew

Richardson, DC, and Laurie Rocco, DC, for carefully

and thoroughly proofreading every chapter, word by

word We thank Pete Broomhall for editorial advice and

assistance and Karen Rehwinkel and the other

profes-sionals of the Elsevier team and Saunders for providing

encouragement, advice, and assistance at every turn We

are particularly indebted to our editors, Kellie White and

Kelly Milford, for patiently and gently guiding us through

every stage of production and for attempting to keep us

on task and on schedule.

John A M Taylor Tudor H Hughes

The original two authors of Skeletal Imaging are

enor-mously indebted to Dr Tudor Hughes, a well-respected musculoskeletal radiologist and educator at the Univer- sity of California, San Diego, and the second edition’s recently recruited third author His extensive knowledge and understanding of musculoskeletal disorders is matched by equally impressive skills in researching, fact- checking, writing, and editing In addition to contribut- ing hundreds of fascinating cases from his vast digital

teaching fi les, he improved every chapter of Skeletal Imaging by making them more accessible to and produc-

tive for the reader.

John A M Taylor

For the First Edition

The authors wish to acknowledge their appreciation of

several persons who have generously contributed their

time, effort, and case material during the production of

this text First, as is indicated in the legends associated

with the illustrations, approximately 140 colleagues

contributed one or more cases for inclusion in this atlas

Their willingness to share case material with us is very

much appreciated Of these persons, many deserve

special mention for their donation of several cases: Drs

John Amberg, Appa Anderson, Richard Arkless, Felix

Bauer, Gabrielle Bergman, Eve Bonic, Enrique Bosch,

Sevil Kursunoglu Brahme, Thomas Broderick, Ann

Brower, Clement Chen, Armando D’Abreu, Larry

Danzig, Steven Eilenberg, Douglas Goodwin, Guerdon

Greenway, Jorg Haller, Al Nemcek, Beverly Harger,

Brian Howard, Roger Kerr, Phillipe Kindynis, Michael

Mitchell, Arthur Newberg, Mini Pathria, Carlos Pineda,

Jean Schils, Jack Slivka, Gary Smith, Richard Stiles,

Phillip VanderStoep, Christopher Van Lom, and Vinton

Vint Numerous radiographs illustrating normal

developmental anatomy were donated by Dr David

Sartoris from the University of California, San Diego;

Dr Jeffrey Cooley from Los Angeles College of

Chiropractic; and Dr Beverly Harger from Western

States Chiropractic College The authors also wish to acknowledge a number of persons who have willingly proofread portions of the manuscript at various stages

of completion: Bill Adams, Eve Bonic, Todd Knudsen, Chad Warshel, Peter Broomhall, and especially Gary Smith, who was kind enough to carefully read and re-read every chapter.

The atlas would not have been possible without the input of a team of professionals at WB Saunders: Lisette Bralow, Frank Polizzano, Mary Reinwald, Walt Verbitski, Nicholas Rook, and Nancy Matthews Their expertise and advice were crucial to the production of the atlas.

Finally, two members of our team who from the outset were absolutely essential to the completion of the text deserve recognition for their extraordinary efforts Debra Trudell, our technical assistant, produced the photographic reproductions Catherine Fix, our copy editor, meticulously edited every table, caption, and reference throughout the text Their expertise, attention

to detail, and demand for excellence are evident throughout the atlas The authors are deeply indebted to Debra and Catherine and, indeed, to all of the persons cited here.

x

Many bone and joint disorders affect multiple regions of

the skeleton The tables in this chapter list anomalies and

anatomic variants (Table 1-1), skeletal dysplasias (Table

1-2), spinal dysraphisms (Table 1-3), fractures (Tables

1-4 and 1-5), articular injuries (Table 1-6), articular

disorders (Tables 1-7 to 1-11), bone tumors (Tables 1-12

and 1-13), tumorlike lesions of bone (Table 1-14),

meta-bolic, nutritional, and endocrine disorders (Table 1-15),

hematologic disorders (Table 1-16), osteonecrosis (Table

1-17), osteochondroses (Table 1-18), and infectious orders of bones and joints (Table 1-19) These tables are intended to provide the reader with an overview of the common clinical, laboratory, and radiographic features

dis-of the more common disorders that typically appear in more than one skeletal location Site-specifi c fi ndings and features unique to each anatomic region are discussed further in subsequent chapters.

TA B L E 1 - 1 Developmental Anomalies, Anatomic Variants, and Sources of Diagnostic Error: Concepts

1 Most spinal anomalies occur at transitional areas, such as the craniocervical,

cervicothoracic, and thoracolumbar regions

2 When one anomaly is identifi ed, always search for more because anomalies may

Block vertebraeOdontoid agenesisHypoplastic C1 posterior archTransverse process hyperplasiaTransitional segments

Tarsal coalitionRadial aplasiaGlenoid hypoplasiaFocal gigantismPolydactyly

Anatomic

variant

A modifi cation of some anatomic characteristic that is considered normalUsually not associated with clinical manifestations; often encountered as an incidental fi nding

Areas of normal trabecular diminution or prominence

Prominent Hahn venous channels

Humeral pseudocystWard triangle of femurPseudocystic region of calcaneus

Normal sites of osseous irregularity

Cupid bow confi guration of vertebral body simulating endplate fracture

or Schmorl nodes

Avulsive cortical irregularity of the femur

Overlying normal anatomy

Mach effect overlying odontoid, simulating fracture

Quadriceps muscle plane overlying femur, simulating fracture

Rarefactions, irregularities, depressions, or proliferations of bone may be mistaken for evidence of disease

Anatomic irregularities Normal notch in

superior articulating process, simulating cervical pillar fracture

Normal sclerosis and fragmentation of calcaneal apophysis, simulating

osteochondrosisSlight modifi cations in osseous anatomy may

be judged to be signifi cant

Anatomic variants Osteosclerotic anterior

arch of atlas, simulating an osteoblastic lesion

Rhomboid fossa in clavicle, simulating a destructive lesion

Data from Jones K: Smith’s recognizable patterns of human malformation 6th ed Philadelphia, Saunders, 2005

* The differentiation of anomalies, anatomic variants, and sources of error is often indistinct, owing to considerable overlap in the defi nitions

Entity General Characteristics General Imaging Findings

Achondroplasia Relatively common rhizomelic dwarfi sm

Accentuated lumbar lordosis, waddling gait, prominent forehead, depressed nasal bridge, trident handShort proximal extremities, normal length of spine

Complications

Spinal stenosisBrain stem compression from narrow foramen magnum

Spinal stenosis with posterior scalloping of vertebral bodies and decreased spinal canal diameterVertebral bodies may be fl attened or wedge-shapedDiaphyseal widening of long bones

Narrow thorax, champagne glass pelvisSplayed and cupped metaphyses of long bonesDiastrophic dysplasia Rare autosomal recessive dwarfi ng dysplasia Short stature, progressive scoliosis, kyphosis

Milder, X-linked recessive form seen only in males

Rare lethal form

Also termed hypochondrogenesis

Congenita form

Decreased height of vertebral bodies, pear-shaped vertebrae in childhood, kyphoscoliosis, accentuated kyphosis and lordosis, pectus carinatum, delayed ossifi cation, hypoplasia of the odontoid with atlantoaxial instability

May be localized or generalizedJoint dysfunction, pain, limitation of motion, and a mass may accompany the disease

Resembles large eccentric osteochondroma arising from epiphyses particularly about the knee and ankleBulky irregular ossifi cation extending into soft tissuesComputed tomographic (CT) or MR imaging may be useful to show the exact location and extent of the lesion and the presence of joint involvement

MPS I-H (Hurler syndrome)

Atlantoaxial instability may be presentRounded anterior vertebral margins with inferior beakingPosterior scalloping of vertebral bodies

Paddle ribs, fl ared ilia, coxa valga, and coxa vara deformities

Sheetlike ossifi cation within soft tissues of neck, trunk, and extremities

Hypoplastic vertebral bodies and intervertebral discsApophyseal joint ankylosis

Shortening of thumbs and great toesCleidocranial dysplasia Rare autosomal dominant disorder characterized by

incomplete ossifi cationWidened cranial vaultDrooping shouldersAbnormal gait, scoliosis, hypermobility, and dislocations

of shoulders and hipsDeafness, severe dental caries, and infrequently, basilar impression

Absent or hypoplastic claviclesSpine: multiple midline defects of the neural arch (spina bifi da)

Pelvis: widened symphysis pubis, coxa valga, coxa vara, underdeveloped bones with small pelvic bowlSkull: wormian bones, persistent metopic suture

Osteopetrosis Sclerosing dysplasia

Benign (autosomal dominant), intermediate, and lethal (malignant autosomal recessive) forms

Complications: anemia, osteomyelitis, blindness, deafness, hemorrhage; brittle bones predispose to bone fragility and pathologic fracture

Patterns of osteosclerosis: diffuse osteosclerosis, bone-within-bone appearance, sandwich vertebrae

Continued

Osteopoikilosis Asymptomatic sclerosing dysplasia

No associated complications

Multiple 2- to 3-mm circular foci of osteosclerosisSymmetric periarticular lesions resembling bone islands predominate about the hip, shoulder, and kneeOsteopathia striata Extremely rare asymptomatic sclerosing dysplasia

No associated complications

Regular, linear, vertically oriented bands of osteosclerosis extending from the metaphysis for variable distances into the diaphysis

Metaphyseal fl aring also may be seenMay be related to cranial sclerosis and focal dermal hypoplasia (Goltz syndrome)

Melorheostosis Rare sclerosing dysplasia

Clinical fi ndings

May be associated with intermittent joint swelling, pain and limitation of motion, muscle contractures, tendon and ligament shortening, growth disturbances in affected limbs, and other musculoskeletal abnormalities

Usual pattern: hemimelic involvement of a single limbPeripherally located cortical hyperostosis resembling

fl owing candle wax on the surface of bonesPara-articular soft tissue calcifi cation and ossifi cation may occur and may even lead to joint ankylosis

May be positive on bone scans

Mixed sclerosing bone

dystrophy

Rare condition in which patients have radiologic

fi ndings characteristic of more than one, and occasionally all, of the sclerosing dysplasias

Combinations of osteopetrosis, osteopoikilosis, osteopathia striata, and melorheostosis

Chondrodysplasia

punctata

Conradi-Hünermann syndrome or stippled epiphysesSeveral different types of this rare multiple epiphyseal dysplasia have been identifi ed, including mild and lethal forms

Mild dwarfi sm, mental retardation, and joint contractures

Stippled calcifi cation of vertebral bodies and epiphyses

Type I, the more common form, exhibits milder changes and is associated with a normal life expectancyAssociated with osteoporosis and bone fragility, various degrees of dwarfi sm, blue sclera, ligament laxity, dentinogenesis imperfecta, and premature otosclerosis

Complicated by multiple fractures, deafness, and pneumonia

Severe osteoporosisPencil-thin corticesMultiple fractures of vertebrae and long bonesBowing deformities of long bones, especially lower extremity

Rare cystic form—ballooning of bone, metaphyseal

fl aring, and honeycombed appearance of thick trabeculae

Usually self-limited, resolving by 30-35 years of age

Bilateral fusiform thickening of the diaphysis of the long bones

Cortical thickening and hyperostosis result in increased diaphyseal radiodensity

Marfan syndrome Autosomal dominant connective tissue disorder

Muscular hypoplasia, joint laxity, dislocations, cataractsComplications: aortic aneurysm, lens dislocation

Long slender bones, arachnodactyly, thin corticesKyphoscoliosis in 40%-60% of persons

Posterior vertebral body scalloping from dural ectasiaSignifi cant osteopenia independent from body mass index (BMI)

Ehlers-Danlos

syndrome

Rare connective tissue disorder characterized by joint hypermobility, blood vessel fragility, and skin elasticity; many forms identifi ed

Complications: valvular insuffi ciency, aortic aneurysm and dissection

Posterior scalloping of vertebral bodiesPlatyspondyly and kyphoscoliosisGenu recurvatum and other joint subluxationsHeterotopic myositis ossifi cans

Subcutaneous hemangiomas (calcifi ed phleboliths)

For more detailed discussion, refer to:

Murray RO: The radiology of skeletal disorders 3rd ed New York, Churchill Livingstone, 1989

Taybi H, Lachman RS: Radiology of syndromes, metabolic disorders, and skeletal dysplasias 5th ed St Louis, Mosby-Year Book, 2007

Yochum TR, Rowe LJ: Essentials of skeletal radiology 3rd ed Baltimore, Williams & Wilkins, 2004

TA B L E 1 - 3 Classifi cation of Spinal Dysraphisms*

Closed spinal dysraphisms Closed spinal dysraphisms are covered by skin and therefore are

not exposed to the environment50% have cutaneous birth marksWith subcutaneous mass—lumbosacral

• Lipomas with dural defect: lipomyelomeningocele and lipomyelocele

• Tight fi lum terminale

• Persistent terminal ventricle

• Dermal sinus

Without subcutaneous mass—complex dysraphic states

• Disorders of midline notochordal integration

a Dorsal enteric fi stula

b Neurenteric cysts

c Diastematomyelia

• Disorders of notochordal formation

a Caudal agenesis

b Segmental spinal dysgenesis

* Modifi ed from Rossi A, Gandolfo C, Morana G, et al: Current classifi cation and imaging of congenital spinal abnormalities Semin Roentgenol 41:250, 2006

Closed fracture Comminuted

Depression fracture Compression

Tibial plateau V

One hard bone surface is driven into an apposing softer bone surface Forceful fl

other large osteolytic or osteosclerotic lesions

Not visible on radiographs Bone marrow edema seen on MR imaging;

Fragmentation and possible separation of a portion of the articular surface Adolescent onset most frequent,

Fracture that heals in an improper position Excessive angular or rotational deformity Adults:

TA B L E 1 - 5 Fractures in Children: Concepts and Terminology

Entity Classifi cation Typical Sites of Involvement Characteristics

Incomplete

fractures

Greenstick fracture Proximal metaphysis of the tibia and

the middle third of the radius and ulna

Incomplete fracture that perforates one cortex, extends into the medullary bone, and compresses the opposite cortex

Torus fracture Distal end of radius and ulna and,

less commonly, the tibia

Incomplete fracture resulting in buckling of the cortexUsually involves a longitudinal compression force insuffi cient to create a complete discontinuity of the bone

Most frequent in children and osteoporotic personsLead pipe fracture Radius Combined compressive and angular forces result in a

combination of greenstick and torus fracturesMost frequent in children

Bowing fracture Radius and ulna; less commonly, the

clavicle, ribs, tibia, humerus,

fi bula, and femur

Plastic response of a long tubular bone to longitudinal stress

Bowing occurs in the absence of cortical discontinuity; in the case of neighboring bones (radius and ulna or tibia and fi bula), one bone typically fractures or dislocates, whereas bowing is identifi ed in the adjacent bone

Seen almost exclusively in childrenToddler fractures Distal tibial diaphysis, fi bula, femur,

metatarsal bones, and, less commonly, the calcaneus, cuboid bone, pubic rami, or patella

Acute onset of fracture in children between the ages of

1 and 3 yearsRadiographs may initially be negative; scintigraphy useful

in detecting such occult fracturesClassic toddler fracture: nondisplaced, oblique fracture of the distal tibial diaphysis

Up to 15% of all fractures to the tubular bones in children younger than 16 years of age involve the growth plate and neighboring bone

25%-30% of patients develop some degree of growth deformity

Salter-Harris classifi cation:

Type I (6%) Pure epiphyseal separation; fracture of cartilaginous

growth plate; no fracture of adjacent bonesSlipped capital femoral epiphysis

Type II (75%) Growth plate fracture with associated metaphyseal

fracture; metaphyseal fragment termed Holland fragment or “corner sign”

Thurston-Type III (8%) Growth plate fracture with associated vertically oriented

epiphyseal fractureType IV (10%) Vertical fracture through the epiphysis, growth plate, and

metaphysisType V (1%) Crushing or compressive injury of the growth plate with

no associated osseous fractureFrequently overlooked

Chronic stress injury Growth centers of the distal end of

the radius and ulna in competitive gymnasts; also proximal portion of the humerus, distal ends of the femur and tibia in other young athletes

Chronic application of stress to the developing growth center in vigorous or repetitious physical activityPart of the physis appears widened and irregular with accompanying sclerosis of the adjacent metaphysis; often unilateral or asymmetric distribution

Entity Classifi cation Typical Sites of Involvement Characteristics

Child abuse Traumatic abuse of

About 10% of children younger than the age of 5 years seen for trauma by emergency room physicians have infl icted injuries that are detectable radiographically

in 50%-70% of casesTypical age range is between 1 and 4 years; after this age, children generally are able to escape the abuser

or at least verbalize what has occurredHumeral fractures in infants and femoral fractures in crawling children should raise suspicion of abuse

Imaging fi ndings

Fractures in different phases of healing, subperiosteal hemorrhage with periostitis, metaphyseal corner fractures, physeal injuries, and transverse diaphyseal

or metaphyseal fractures

Differential diagnosis

Accidental fractures such as torus fractures of the distal end of radius, toddler’s fractures of the tibia, clavicular and skull fractures; normal periostitis of infancy, metaphyseal changes of normal growth, congenital insensitivity to pain, rickets, osteogenesis imperfecta, metaphyseal and spondylometaphyseal dysplasia, Menkes kinky hair syndrome, congenital syphilis, and infantile cortical hyperostosis (Caffey disease)

TA B L E 1 - 6 Articular Injuries: Concepts and Terminology

Joint effusion Knee

ElbowTibiotalar jointHip

Glenohumeral joint

Accumulation of excessive synovial fl uid within jointBland effusion associated with acute injury or internal joint derangement

Nonbloody effusions usually appear 12-24 hours after injuryAbsence of effusion with severe trauma may indicate capsular rupture of such a degree that fl uid extravasates into the soft tissues surrounding the joint (especially the knee)

Proliferative effusion associated with synovial proliferation as in infl ammatory arthropathy and villonodular synovitisPyarthrosis: purulent material in joint from pyogenic septic arthritisHemarthrosis Any injured joint Accumulation of blood within joint

Hemarthroses usually result in joint effusion within the fi rst few hours after injury

May result from acute ligament injury, villonodular synovitis, hemophilia, synovial hemangioma, or other articular diseasesLipohemarthrosis Knee

Glenohumeral jointHip

Accumulation of blood and lipid material within synovial jointFat-blood interface seen on cross-table horizontal beam lateral radiographs and on transaxial and sagittal MR imagesDouble fl uid-fl uid levels on MR images are more specifi c for lipohemarthrosis than a single fl uid-fl uid level

Usually related to acute intraarticular fracturePneumolipohemarthrosis Hip Accumulation of gas, blood, and lipid material within synovial joint

Typically seen after fracture-dislocationMost evident on CT scans

Sprain Acromioclavicular joint

Tibiotalar jointKneeElbow

Grade I: Mild sprain—stretching of the ligament but no tearGrade II: Moderate sprain—partial ligamentous disruptionGrade III: Complete ligamentous rupture (with or without dislocation)

Subluxation Glenohumeral joint, patellofemoral

joint, and many other sites

Partial loss of contact between two osseous surfaces that normally articulate

Dislocation Glenohumeral joint, acromioclavicular

joint, patellofemoral joint, hip, apophyseal joints, and many other sites

Complete loss of contact between two osseous surfaces that normally articulate

Trauma to symphyses Symphysis pubis, discovertebral joint,

and manubriosternal joint

Abnormal separation of a joint containing fi brocartilage that normally

is only slightly movableCartilaginous nodes, posttraumatic annular vacuum cleft, limbus vertebrae, and apophyseal ring avulsion fractures resulting from discovertebral trauma

Heterotopic ossifi cation Large muscle groups in thigh, leg,

Well-defi ned region of ossifi cation aligned parallel to the long axis

of the tibia and fi bula may be evident within 6-8 weeksZonal phenomenon—ossifi c periphery with radiolucent centerCleavage plane may be evident between ossifi cation and adjacent bone, helping to differentiate it from parosteal osteosarcomaAssociated periostitis may relate to subperiosteal hemorrhageMay be surrounded by edema seen on MR images

Differential diagnosis

Aggressive neoplasms such as parosteal, periosteal, and soft tissue osteosarcoma, and Ewing’s sarcoma, liposarcoma, and synovial sarcoma

Knee Hip Hand Foot Acromioclavicular joint Sacroiliac joint

Accompanies aging Clinical fi

Absence of soft tissue swelling Absence of osteoporosis Fibrous ankylosis (rare) Unilateral or bilateral asymmetric distribution

Glenohumeral joint Elbow Knee Hip Hand Foot Sacroiliac joint Acromioclavicular joint

(See Primary osteoarthrosis) Appearance of osteoarthrosis may obscure (or be obscured by) that of the primary articular process

C5-C7 T2-T5 T10-T12 L4-S1 Discovertebral junction Uncovertebral joint Apophyseal joint Costovertebral joint

Intervertebral osteochondrosis Spondylosis deformans Uncovertebral osteoarthrosis Apophyseal joint osteoarthrosis Costovertebral joint osteoarthrosis

patients with severe degenerative changes may have minimal or no symptoms

Subchondral bone sclerosis Schmorl (cartilaginous) nodes

anterolateral aspect of the spine (see Diagnostic criteria below)

Absence of apophyseal joint bony ankylosis and sacroiliac joint erosion, sclerosis

Hand Foot Wrist Knee Elbow Glenohumeral joint Acromioclavicular joint Cervical spine

Radiographic erosions or periarticular osteopenia, or both,

Positive LE phenomenon (8%-27% of patients) Imaging fi

Marginal and central subchondral erosions Subchondral cysts Cortical atrophy and osteolysis Absent or mild sclerosis Periarticular osteoporosis Synovial cysts Joint instability

Sacroiliac joint Thoracolumbar spine Cervical spine Symphysis pubis Hip Shoulder Heel

Most common seronegative spondyloarthropathy Clinical fi

Iritis (20% of cases) Aortic insuffi

Pleuritis Infl

Negative rheumatoid and LE factors HLA-B27 histocompatibility antigen present in 90% of

Hand Foot Sacroiliac joint Thoracolumbar spine Cervical spine

Seronegative spondyloarthropathy Less common than ankylosing spondylitis Two to 6% of patients with psoriatic skin lesions

Combination of spondyloarthropathy and sacroiliitis

Signs and symptoms Long history of psoriatic skin lesions:

Mild anemia Elev

Negative for rheumatoid factor Imaging fi

Absence of osteoporosis Severe joint space destruction with marginal

Low back pain,

synovitis-acne-pustulosis-hyperostosis-osteomyelitis (SAPHO) syndrome or pustulotic arthro-osteitis (P

Ocular abnormalities Early:

Absence of osteoporosis Diffuse joint space loss

ulcerative colitis and Crohn disease who develop spondylitis or sacroiliitis

Entity Typical Age of Onset (Y ears)

Initial soft tissue edema Soft tissue atrophy Sheetlik

Phalangeal tuft erosion Conical appearance of fi

Acrosclerosis Erosions and subchondral cysts (rare) Phalangeal tuft resorption Osteonecrosis:

whether they received corticosteroid therapy; possibly caused by v

Hand Wrist Foot

diseases include combinations of rheumatoid arthritis

Knee Symphysis pubis Hand Wrist Hip Shoulder Elbow Spine

May be precipitated by local damage Clinical patterns Most persons are asymptomatic;

Bilateral asymmetric involvement Local soft tissue swelling Calcifi

fragmentation resembling neuropathic osteoarthropathy

disease allowing differentiation from degenerative joint disease include prominent calcifi

Shoulder Rare sites:

Wrist Hand Elbow Hip Neck

Hip Shoulder Spine

hyperuricemia without signs or symptoms; 20% of patients develop acute arthritis or renal calculi,

Hand Wrist Knee Hip Shoulder

Spine Hip Knee

Presence of homogentisic acid in urine and plasma Imaging fi

Ankle Hip Shoulder Hand Foot

plasma clotting factors and defective blood coagulation

Manifested in men and carried by women Two main X-link

Osseous erosions and cysts Joint space narrowing Sclerosis and osteophytes Osteonecrosis Imaging appearance of joints closely

motor neuron) lesions can lead to neuropathic osteoarthropathy

Hypertrophic and atrophic forms Axial sk

zygapophyseal joint destruction May resemble infectious spondylodiscitis Joint collapse

Hip Knee Shoulder Elbow

typically progress to large accumulations possessing trabeculae

Knee Hip Elbow Ankle

50% of patients have history of trauma Extraarticular form is termed

Soft tissue swelling Cystic erosions on both sides of the joint Hemorrhagic joint effusion Eventual osteoporosis Well-preserved joint space until late in the

Knee Hip Elbow

cartilaginous and osteocartilaginous bodies by the synovial membrane

pain may resemble that of an internal joint derangementJoint locking and instability may occur Focal recurrence after surgery Malignant degeneration (rare)

Erosion of adjacent bone Secondary osteoarthrosis Noncalcifi

occur as a result of degenerative joint disease

TA B L E 1 - 1 1 Articular Disorders With Skin and Joint Findings*

Disorders of the Epidermis

Psoriasis Peripheral arthritis, sacroiliitis Scaling erythematosus papules on scalp and

extensor surfacesUlcerative colitis Like psoriasis and other seronegative

spondyloarthropathies

Maculopapular eruptions, purpura, aphthae, erythema nodosum, erythema multiforme, pyoderma gangrenosum

Disorders of the Dermis

Ehlers-Danlos syndrome Joint effusion, dislocation, and contracture Hyperelasticity and fragility of skin, soft tissue

calcifi cation

Disorders of the Sebaceous Glands

Pustular acne (Pustulotic arthro-osteitis

(PAO) or SAPHO)†

SAPHO: abbreviation for synovitis, acne, pustulosis, hyperostosis, and osteitisOsteoarticular infl ammation involving anterior chest wall, spine, pelvis, sacroiliac joints

PolyarthralgiaHyperostosis

Nodulocystic pustules with scarring primarily

on the palms of the hands and plantar surface of the feet

Acne fulminans Sacroiliitis, synovitis, and osteolytic lesions Acute ulceration and hemorrhage

Acne conglobata Small joint erosions, sacroiliitis, and

syndesmophytes

Large infl amed cysts

Disorders of Sweat Glands

Hidradenitis suppurativa Sacroiliitis, phalangeal periostitis Infected sweat glands with abscesses in groin

and axilla

Tumors and Tumorlike Conditions

Disseminated ovarian or other carcinoma Shoulder and hand arthritis and contractures Palmar fasciitis

Immunologic and Allergic Cutaneous Disorders With Arthralgia

Drug reaction/serum sickness Arthralgias Urticaria

Infections, Behçet syndrome, drugs Arthralgias Erythema nodosum

Collagen Vascular Diseases

Systemic lupus erythematosus Subluxations without erosions Malar butterfl y rash

Systemic periarteritis nodosa Migratory polyarthralgia Ulceration, nodules, purpuric plaques

Scleroderma Infl ammatory arthritis Tight skin, fi brosis, telangiectasia

Rheumatoid arthritis Symmetric small joint erosive synovitis Subcutaneous nodules, petechiae, and purpuraJuvenile rheumatoid arthritis Asymmetric large joint erosive synovitis Maculopapules on limbs, trunk and faceMulticentric reticulohistiocytosis Destructive polyarthritis, erosive synovitis Multiple cutaneous nodules, characteristically

around fi ngernailsRelapsing polychondritis Rheumatoid-like arthropathy Swollen ears, saddle nose, erythema nodosum

* Reprinted with permission from Kilcoyne RF: Arthritis associated with dermatologic conditions Semin Musculoskeletal Radiol 7:227, 2003

† From Hyodoh K, Sugimoto H: Pustulotic arthro-osteitis: Defi ning the radiologic spectrum of the disease Semin Musculoskeletal Radiol 5:89, 2001

Entity Skeletal Findings Skin Findings

Infections

Viral

Measles, rubella, parvovirus, viral

hepatitis, herpes simplex, vaccinia

Arthralgias Urticaria and other rashes

Bacterial

Rheumatic fever

Disseminated gonococcal infection

Transient arthralgia/arthritisSeptic arthritis or reactive allergic arthritis

Erythema marginatumScattered acral papular and vesicopustular lesions

Leprosy Osteomyelitis, infective arthritis, neuropathic

joints

Thickening of skin over face and extremities; autoamputation

Spirochetal

Syphilis, acquired Neuropathic joints Different skin lesions in primary, secondary,

and tertiary stagesLyme disease Mono- or migratory arthritis, chronic erosive

arthritis

Erythema chronicum migransFungal

Sporotrichosis

Coccidioidomycosis (valley fever)

Direct contiguous spread or hematogenous infection

Acute desert rheumatism or chronic arthritis

Suppurating nodular lesions of wrist, ankle, and elbow

Erythema nodosumPossibly infectious

Diseases of Nutrition and Metabolism

Acromegaly Widened joint spaces, early degeneration Skin thickening of hands, feet, and face

Ochronosis Chondrocalcinosis, early degeneration Slate blue skin pigmentation

Hemochromatosis Generalized arthropathy, chondrocalcinosis Bronze diabetes

Gout Discrete articular erosions, especially toe Tophi, soft tissue swelling, erythema

Environmentally Caused or Drug-Related Diseases

Vinyl chloride exposure Acro-osteolysis Scleroderma-like

Retinoids Hyperostosis, DISH-like changes,

enthesopathy, osteoporosis, premature closure of physes

Dry skin, epilation, reduced sebum

Most common malignant tumor of bone Most frequent primary sources in adults:

Permeative or moth-eaten osteolysis (75% of patients) Diffuse or patchy osteosclerosis or mixed pattern of

Pathologic fracture Soft tissue mass (rare) Periosteal reaction (rare) Bone expansion (rare) Cortical metastasis Prev

of nutrient arteries into the bone (cookie-bite lesions)

Tibia (21) Humerus (11) Pelvis (7)

may result from malignant transformation of benign neoplasms

Prominent aggressive periosteal reaction common Preferential involvement of the metaphysis

Osteosclerotic surface lesion of bone Large radiodense

Tibia (13) Pelvis (13) Femur (11) Foot (11)

radiographic characteristics of malignancy and can be diffi

be slightly younger than those with central chondrosarcoma

Femur Tibia Radius Spine Humerus

radiographic appearance is an inaccurate guide to determining malignancy of lesion;

Forty to 60% recurrence rate for all giant cell tumors Tumor implantation may occur at distant sites

Tibia (16) Humerus (11) Pelvis (10)

Rare malignant neoplasm of bone Fibrosarcomas of bone have a poorer prognosis

Two main types: 1

Sequestrum may be seen Minimal sclerotic reaction or periostitis Central or eccentric location in tubular bones Soft tissue masses are common

initially and result from pressure on adjacent structures (rectum,

Reactive bone sclerosis Periostitis rare

Occasional bone sclerosis Pathologic fracture (15% of patients) Most lesions central and diametaphyseal in location

Pelvis (27) Ribs (26) Humerus (15)

disease of plasma cells and represents the most common primary malignancy of bone

V Pathologic fracture 97% osteolytic;

Pelvis (13) Femur (16) Sternum (15)

Localized form of plasma cell myeloma 25% of cases of plasma cell myeloma are solitary

eletal abnormalities occur in 10%-25% of patients; more common in adults than in children

Pelvis (18) Spine (13) Tibia (9)

No race predilection Clinical fi

eletal involvement in up to 30% of patients with non-Hodgkin lymphoma

Common cause of pathologic fracture Diffuse or localized sclerotic lesions are rare

form (up to 70% of cases) than adult form (less than 20% of cases)

Diffuse osteopenia (15%-100% of cases) Radiolucent or radiodense transverse metaphyseal

Osteolytic lesions (30%-50% of cases) Periostitis (10%-35% of cases) Osteosclerosis (5%-10% of cases) Radiodense metaphyses more frequent in patients

radiating osseous spicules that intermingle with the surrounding trabeculae of the spongiosa

less than 1 cm in diameter and may not be visible on routine radiographsComputed tomography is gold standard to show nidus Intracapsular lesions provok

Femur (14) Tibia (10) Foot (7)

Approximately 95% of osteoblastomas are benign Clinical fi

Often resembles large osteoid osteoma Spine:

Femur (11) Foot (7) Humerus (7) Ribs (5)

transformation to chondrosarcoma (fewer than 1% of cases) or pathologic fracture

Lobulated endosteal scalloping Stippled calcifi

Multiple enchondromas Tubular radiolucent areas extending into the metaphysis

Shortening and deformity of affected bones Frequent calcifi

Multiple enchondromas and soft tissue hemangiomas Unilateral distribution in 50% of cases Malignant transformation rate:

Benign epiphyseal tumor of cartilage origin Frequently results in joint pain

Circular osteolytic lesion 1 to 6 cm in diameter Arise from epiphyses and apophyses of long bones;

Thin sclerotic margin Calcifi

Soft tissue mass and pathologic fracture rare Occasionally periosteal reaction may be seen on routine radiographs and edema may be seen on magnetic resonance images

cartilaginous metaplasia within the periosteal membrane

excrescence arising from the surface of the metaphyses of long bones or

Spinal lesions arise from the posterior arch Signs suggesting malignant tr

virtually excludes presence of malignancy; microscopic biopsy fi