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`Sandoz v. AbbVie
`Sandoz Ex. 1029
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`Ex. 1029 - Page 1
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`Ex. 1029 - Page 1
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`

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`Textbook of
`
`Rheumatology
`
`Ex. 1029 - Page 2
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`

`

`Textbook of
`Rheumatology
`
`Fourth Edition
`
`Volume I
`
`WILLIAM N. KELLEY, M.D.
`Chief Executive Officer
`University of Pennsylvania Medical Center
`Executive Vice President and Robert G. Dunlop
`Professor of Medicine and Biochemistry and Biophysics
`University of Pennsylvania
`Dean, University of Pennsylvania School of Medicine
`Philadelphia, Pennsylvania
`
`EDWARD D. HARRIS, Jr., M.D.
`Arthur L. Bloomfield Professor and Chairman
`Department of Medicine
`Stanford University School of Medicine
`Stanford, California
`
`SHAUN RUDDY, M.D.
`Elam Toone Professor of Internal Medicine,
`Immunology, and Microbiology
`Chairman
`Division of Rheumatology, Allergy, and Immunology
`Department of Internal Medicine
`Medical College of Virginia
`Virginia Commonwealth University
`Richmond, Virginia
`
`CLEMENT B. SLEDGE, M.D.
`John B. and Buckminster Brown Professor of Orthopedic Surgery
`Harvard Medical School
`Chairman
`Department of Orthopedic Surgery
`Brigham and Women's Hospital
`Boston, Massachusetts
`
`W.B. SAUNDERS COMPANY
`Harcourt Brace Invannvich. lac.
`Philadelphia London Toronto Montreal Sydney Tokyo
`
`Ex. 1029 - Page 3
`
`(cid:9)
`

`

`W.B. SAUNDERS COMPANY
`Harcourt Etrace Jovanovich, Inc.
`The Curtis Center
`Independence Square West
`Philadelphia.. Pennsylvania 19106
`
`Library of Congress Cataloging-in-Publication Data
`Textbook of rheumatology William N. Kelley „ . [et al.].-
`4th ed.
`
`p. (cid:9)
`Includes bibliographical references and indexes.
`
`cm.
`
`ISBN 0-7216-3157-6 (set)
`
`I. Kelley, William N., 1939-
`1. Rheumatology. (cid:9)
`2- Rheumatic Diseases.
`1. Arthritis. (cid:9)
`[DNLIvl: (cid:9)
`WE .544 T355 1993]
`
`RC927.T49 1993 (cid:9)
`
`616.7'23—dc20
`
`DNLM/DLC
`for Library of Congress (cid:9)
`
`92-48331
`CIP
`
`TEXTBOOK OF RHEUMATOLOCY, Fourth Edition (cid:9)
`
`ISBN
`
`Volume I (cid:9)
`0-7216-3155-X
`Volume II (cid:9)
`0-7216-3156-8
`Two Volume Set 0-7216-3157-6
`
`Copyright e, 1993, 1989, 1985, 1981 by W.B. Saunders Company.
`
`All rights reserved, No part of this publication may be reproduced CV transmitted in any form or by any
`means, electronic or methanicat, including photocopy, recording, or any information storage and retrieval
`system, without permission in writing from the publisher.
`
`Printed in the United States of America.
`
`Last digit is the print number: (cid:9)
`
`9 (cid:9)
`
`8 (cid:9)
`
`7 (cid:9)
`
`6 (cid:9)
`
`5 (cid:9)
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`4 (cid:9)
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`3 (cid:9)
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`2 (cid:9)
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`1
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`Ex. 1029 - Page 4
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`

`

`Chapter 37
`Imaging
`
`Donald Resnick
`Marie-losee Benhiaurne
`David Sartoris
`
`INTRODUCTION
`
`The routine radiographic examination is a key-
`stone in the diagnosis and management of the patient
`with articular disease. In some patients, the diagnosis
`may initially be suggested by standard radiographic
`films, whereas in other patients with a known clinical
`diagnosis, the extent and the severity of the disease
`process may be documented by such techniques.
`Furthermore, serial radiographic examinations pro-
`vide evidence of the therapeutic response of the
`disease process. In this chapter, we discuss routine
`radiographic techniques and additional imaging
`methods, cardinal roentgen signs of articular disease,
`and the radiographic findings at specific "target"
`areas of the major articular disorders. As the major
`advances in imaging of musculoskeletal disorders in
`the last 5 years have involved computed tomography,
`(CT) and magnetic resonance (MR) techniques, these
`two methods are emphasized in this chapter.
`
`IMAGING TECHNIQUES AND METHODS
`
`Plain Film Examination. Appropriately selected
`plain films form the initial step in the radiographic
`evaluation of the articubr disease. The choice of
`radiographic projections for each anatomic area is a
`decision that deserves careful consideration. The
`need for a comprehensive examination to document
`the extent and configuration of the disease process
`must be balanced with the consideration of expense,
`comfort, and radiation exposure to the patient, who
`may be expected to have numerous radiation exam-
`inations over many years_
`In most instances, multiple radiographic projec-
`tions of a number of joints are indicated. Table 37-I
`lists the suggested radiographic projections for the
`optimal evaluation of specific anatomic areas- .In the
`patient with monoarticular or pauciarticular disease,
`such a protocol may be followed Closely. In the
`patient with polyarticular disease, however, obtain-
`ing the numerous radiographic views listed in Table
`37-1 would be considered excessive in almost all
`instances. In these patients, the initial radiographic
`examination should be individually tailored to as
`great an extent as possible.
`A "tailored" arthritis series is useful in those
`patients with polyarthritis who have either a known
`or a highly Likely clinical diagnosis. In this setting,
`plain films are selected that most optimally show the
`
`major target areas of the disease as well as additional
`areas of clinical significance_ For example, the patient
`with rheumatoid arthritis requires careful radio-
`graphic evaluation of the hands, wrists, feet, knees,
`shoulders, and cervical spine, whereas the patient
`with calcium pyrophosphate dihydrate (CPPD) crys-
`tal deposition disease usually requires analysis of
`only the hands, wrists, knees, and syrnphysis pubis.
`The situation often arises in which a patient has
`polyarthritis without a specific clinical diagnosis. In
`this instance, a so-called standard arthritis series is
`useful; projections are selected to provide adequate
`visualization of a large number of major target areas
`with a minimum of radiation exposure. A suggested
`standard arthritis series, consisting of 15 radiographs,
`is listed in Table 37-2.
`The follow-up radiographic examination ob-
`tained during the course of treatment need riot be as
`extensive as the initial survey. In many instances it
`can be limited to a few symptomatic areas or areas
`where unsuspected progression of disease may lead
`to catastrophic consequences., such as the cervical
`spine in patients with rheumatoid arthritis.
`Use of intensifying screen in a radiographic film
`cassette combined with double-emulsion radio-
`graphic film allows formation of a radiographic image
`with considerably less radiation exposure to the pa-
`
`Table 37-1. RADIOGRAPHIC PROWL-DONS
`
`Fland
`West
`Elbow
`Shoulder
`
`Foot
`
`Ankle
`Knee
`
`E lip
`
`Sacroiliac joint
`
`Lumbar spine
`
`Thoracic spine
`Cervical spine
`
`Fosteroanterior, oblique
`Posteroanterior, oblique, Lateral
`Anteroposterior. lateral
`Anteroposterior with internal rotation of
`the humerus; anteroposterior with
`external natation of the humerus
`Anteroposterior, oblique, lateral (including
`calcaneus)
`Anteroposterior, lateral
`Antempnsterior. lateral. -tunnel"
`(anteroposterior in serniflexionl, axial
`patellar ("sunrise")
`Antenipos.terior of pelvis, onterup.isterinr
`of hip with internal rotation of leg,
`anteroposterfor of hip with external
`rotation of IE r frog teg")
`Anteropusterior, anteroposterior with 30
`degrees cephalic angulation of central ray
`Anteroposterior, obliques, lateral, lateral
`coned dawn to 13-5!
`Anteroposterior, lateral
`Anteroposterior„ Ob.] iques, latura! with neck
`in flexion, lateral with neck in extension,
`"open-mouth" °deltoid view
`
`579
`
`Ex. 1029 - Page 5
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`(cid:9)
`(cid:9)
`(cid:9)
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`(cid:9)
`

`

`580 (cid:9)
`
`Diagnostic Tests and Procedures in Rheumatic Diseases • 37
`
`Table 37-2. ARTHRITIS SURVEY
`
`Area (cid:9)
`Hand and wrist
`Foot
`Knee
`Pelvis and hips
`Thorax and shoulders
`Cervical spine
`
`Projection
`
`Posteroanterior, obliques
`Anteroposterior, obliques, lateral
`Anteroposterior, lateral]
`Anreroposterior
`Anteroposterior
`Lateral with neck in flexion.
`
`dent. A small decrease in radiographic resolution,
`however, is the price paid for this considerable dim-
`inution in radiation exposure. Occasionally, in eval-
`uating diseases such as rheumatoid arthritis, osteo-
`myelitis., septic arthritis, or hyperparathyroiclisrn,
`greater resolution may be important in establishing
`a diagnosis at an early stage,' 3 In these instances,
`increased radiation exposure to a relatively radiore-
`sistant area of the body, such as the hand, the wrist,
`or the foot, may be acceptable for the important
`diagnostic information that is obtained, With vir-
`tually any radiographic unit, use of single-emulsion
`film and a nonscreen vacuum-packed cassette, re-
`fered to as the ntaininographic technique, allows high-
`resolution images to be obtained. Furthermore, op-
`tical or radiographic magnification can be extremely
`helpful. With the magnification technique, images
`may be obtained using rnicrofocal spot radiographic
`tubes, such as are present on many angiographic
`units, or specially designed magnification units. It
`should be emphasized that these are specialized
`techniques and should be used only in selected
`clinical situations.
`Radiographs of an articulation obtained during
`weight bearing or the application of stress or traction
`may provide valuable supplemental information to
`the plain film radiographic examination. Weight-
`bearing views of the knees are especially valuable in
`the evaluation of patients with osteoarthritis4 and
`may allow a more exact delineation of cartilaginous
`loss as well as abnormal varus or valgus anguJation
`of the joint. Stress radiographs may be used to assess
`soft tissue and bony stability following injury to the
`knee, ankle, acrornioclavicuiar joint, or first metacar-
`pophalangeaI joint.' Upright lateral radiographs of
`the lumbar spine obtained after prolonged standing
`may accentuate bony neural arch defects (spondylol-
`vsis) or intervertebral slippage (spondylolisthesis).
`Radiographs of the pelvis obtained with the patient
`standing on one leg at a time may demonstrate
`instability of the sacroiliac joint or symphysis pubis.t.
`Radiographs obtained during application of trac-
`tion across a joint also may prove useful in selected
`circumstances. Demonstration of subtle transchcin-
`dral fractures in osteonecrosis of the femoral head
`may be improved with this technique.'' Such traction
`may also stimulate the release of gas, primarily
`nitrogen, into the joint cavity, an occurrence that
`usually will rule out the presence of a joint effusion
`and allows visualization of a portion of the cartilagi-
`nous surface. This method is mostly used in children
`to rule out a septic arthritis.
`
`Conventional Tomography. Conventional to.
`mography can aid both in the identification of sdk
`abnormalities and in the more precise deliaeatian
`previously identified lesions. fri some anatornicare6
`such as the temporornandibular joint 0-141) and skr,
`noclavicular and costovertebral articulations, ph:,
`radiographs are rarely adequate and couvenlior.
`tomography is often indicated.
`Arthrography and Bursography. injection €4 rj.
`diopaque contrast material, air, or both, hop a
`or bursa may be essential in evaluating a nuider...
`articular disorders.* Contrast arthrographi, is ms_:
`often used in the knee and shoulder to iclent.,
`surgically repairable soft tissue injuries such as
`niscal or rotator cuff tears, Aspiration arthrograty
`allows confirrnatiort of suspected joint sepsis; iluo-
`roscopically guided intra-articular needle placenx.
`is particularly useful in recovering fluid from den
`articulations such as the glenohumer-al joint or
`hip. Subsequent instillation of a small amount Li
`radiographic contrast agent allows verification NI
`the joint space was indeed entered and may all
`yield important information concerning the exlenti
`periarticular soft tissue destruction, An kapott-
`indication for aspiration arthrography is evaiut.:
`of the patient with a painful total hip or knee pm.:
`thesis to differentiate conclusively between rfacir.
`infection and aseptic loosening of the prostheses.
`Air arthrography, usually combined "with coml.
`tional tomography, often is of great value in IFS
`identification of transchondml fractures and init.:-
`articular osteocartilaginous bodies. ArthregraRliF
`also may provide a firm diagnosis in cases N-
`mented villonodular synovitis or idiopathic s4'ncil92l
`osteochondrolnatosis,1 Finally, arthrography °11,
`serve as a method of treatment with the "brisersar
`procedure, or distension arthrography in cases ‘1.1
`adhesive capsulitis, in which the articular eaPsni?n
`progressively distended with a mixture of lidocaille
`or bupivacaine hydrochloride and steroids until 62
`capsule ruptures or relief of symptoms is obtaind-
`Bursography has its greatest value in evaltiaiir ...
`lesions of the subacronniaI bursa in the shoulder.—
`In this location, bursitis, intrabursal osteacA
`nous bodies, partial rotator cuff tears, and causes1
`shoulder irnpingernertt may be identified. At
`same time, instillation of local anesthetic agents
`anti-inflammatory medications directly into the bar9
`can serve both diagnostic and therapeutic pLIIrse
`
`Computed Tomography
`Introduction and Technical Consiclerations.. ]n
`an age in which MR imaging is increasinglY belq
`employed, CT remains an excellent investigative°.
`for rnusculoskeletal disorders used either salelY,.13:,:i
`combination with MR. CT permits cro5s-5eca--i.
`images to be displayed with excellent structural d
`iriition of both soft tissues and 1.)ones, In nitls t.cgt
`c umstances, CT scans provide more thar' 5°6(1'61
`information and obviate any other imaging exani`
`
`Ex. 1029 - Page 6
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`

`

`Donald Resnick, Marie-Josee Berthiaurne, and David Sartoris • imaging (cid:9)
`
`581
`
`nation. Nevertheless, significant drawbacks limit its
`performance. For instance, artefacts caused by the
`presence of metallic objects greatly diminish image
`quality. Also, direct images obtainable during CT are
`generally in the transaxial plane, Although most CT
`units have software capable of reconstructing original
`image data in any plane or in three dimensions,'
`sometimes this requires increased patient radiation
`exposure or an increase of examination time, and
`often a significant loss of definition in the recon-
`structed images.
`CT frequently serves as a supplement to conven-
`tional imaging techniques. Because different factors
`often reduce its availability, it is of the utmost im-
`portance that clinical and imaging records be re-
`viewed prior to CT to select the most appropriate
`examination protocol for any given condition.
`Each examination begins with a scout film cov-
`ering the area of interest. It is important to note that
`although CT generally is limited with regard to initial
`imaging plane, the patient's body or specific regions
`of the body can, to some extent, be positioned in
`such a way that differentplanes other than transaxial
`can be produced. As a rule, the more distal the body
`part to be studied, the greater the number of possible
`planes that can be obtained. For example, transaxial
`views are required for the lumbar spine, whereas
`virtually all planes are obtainable for a hand, elbow,
`or foot. Positioning of the subject also may be limited
`by the patient's comfort.. physical state, and cooper-
`ation. The next important step relates to the choice
`of slice thickness and interval. Although slice thick-
`ness and interval arc included as part of many
`standard protocols, it is important to tailor these
`specific aspects of the procedure whenever neces-
`sary. The choice depends primarily on the type, size,
`and location of the lesion, the need for further
`reformation of the images, the duration [lf the ex-
`arninafion, and the resulting radiation exposure.
`CT images are digitalized and depict various
`structures in terms of different densities on a stan-
`dard gray scale. The distribution within the range of
`the gray scale can be modified to enhance soft tissue
`relationships or bony structures but not both of these
`at the same time on one image. Generally, two sets
`of images are obtained at different "window" levels
`to show optimally bone and soft tissue structures_
`The relative densities of all structures are expressed
`in Flounsfield units (1-IU). Arbitrarily, gas has the
`lowest density at —10[10 HU and bone or metal the
`highest at + 1000 HU. Water is considered being
`neutral with a value of 0 HU, a- depicts the shape,.
`structure, content and, above all, the extent of a
`lesion with a precision that is far beyond that of any
`conventional imaging technique- It is possible to rely
`on the Hourisfield values to predict the nature of a
`given lesion,. including cysts (Fig. 37—I), fat, and
`calcification; however, density alone should not be
`regarded as a precise histologic indicator- One must
`rely on the results of a combination of clinical,
`laboratory, conventional, and other imaging tech-
`niques.
`
`Figure 37-1. Synovial cyst of the hip in a patient with rheumatoid
`arthritis. Observe the erosion of the femora] head and femoral
`neck and a large eysik mass Invared anterior to th (cid:9)
`farrow).
`
`In some specific clinical settings, the simultane-
`ous use of positive or negative contrast material
`enhances the value of CT. In the musculoskeletal
`system, this has been most true for spine studies in
`which intrathecal positive contrast material is used.
`Because of the invasiveness and the risks related to
`the injection of intrathecal iodinated material and the
`more extensive use of MR, this type of procedure
`has been used less frequently in the past few years.
`Nevertheless, injection of positive contrast material
`into the intrathecal space in combination with Cr
`remains extremely useful in acute or emergency
`settings when patients cannot undergo an MR ex-
`amination because of clinical status or because of
`medical equipment attached to them. Intravenous
`contrast material is mainly used to characterize soft
`tissue masses or the vascular status of a given lesion,
`and positive or negative contrast material (air), or
`both, is used frequently in articular studies in which
`it is particularly useful to evaluate the articular sur-
`face; to detect intra-articular bodies, such as in pri-
`mary synovial osteochondromatosis; and to study
`other articular components, The software for three-
`dimensional reconstruction of image data is not yet
`generally available, Nevertheless, it holds great
`promise and is espedaily useful in the study of areas
`of complex anatomy.. such as the facial bones, pelvis..
`spine, and hindfoot, Moreover, it has important
`applications in trauma, reconstructive surgery, and
`prosthetic design,'5.
`Clinical Indications. CT is efficient and practical
`in studying axial structures such as the spine, pelvis,
`sacrum and sacroiliac }Dints, sternum and sternocla-
`vicular joints, hip (Fig. 37-2), shoulder, hindfoot,
`and midfoot. The wrist (Fig, 37-3) and TMJ are now
`better studied by MR imaging. Some specific indica-
`tions and applications of Cr scanning are discussed
`briefly here.
`Trauma. CT has its greatest advantage in the
`evaluation of the acutely traumatized patient, espe-
`cially when the injury involves axial structures. It
`allows the identification of fractures and dislocations.
`It is extremely useful in the investigation of acute
`spinal trauma'. Es and, in that regard, is superior to
`plain films. Standard CT slices at the suspected level
`
`Ex. 1029 - Page 7
`
`

`

`582 (cid:9)
`
`Diagnostic Tests and Procedures in Rheumatic Diseases • 37
`
`acetabular fragment displacement, CT again is to
`perior to plain films or even convenricuu,
`to mograrns,"' 25 Furthermore, the pelvis is frequently
`the site of complex fractures that can be well deb
`eated only by CT, often with multiplanar or thief
`dimensional images.'
`Other traumatized articulations also benefit fri-
`CT evaluation. The sternum and sternoclavirUz
`joints often are poorly demonstrated by conventioru
`imaging techniques, but CT reveals their anatcc';.
`with great precision. Furthermore, it has the aka.
`tage of providing information about the iriediastirtm
`at the same time.=7. 241 The injured glenohumeral
`is much better studied with CT than with plain tilffs
`Humeral head dislocation'" is a frequent diagrom
`Although the diagnosis can be made on plain filn
`the associated bone injury and cartilaginous iniune
`are better assessed with CT. The Bankart defonnit%
`a cartilaginous or bone lesion of the inferior
`rim cavity, and the Hill-Sachs deformity, an imp:-
`tion fracture of the posterior aspect of the hum
`head at the level of the coracoid process, lima
`indicate previous anterior glenohumeral disloratkr
`and frequently are not detected when plain tihe
`alone are used."'
`CT is of more limited use in the evaluation et
`trauma to the foot, hand, or elbow," although b
`imaging method is widely used for the asses
`of calcaneal,' talar (Fig. 37-4), and wrist fractur:,
`and the presence of loose bodies in the elbow.
`studies have replaced CT for evaluation of traunui
`damage to ligaments, articular cartilage. and meek:
`of the knee.
`Infections. CT plays a significant role in
`diagnosis of osteomyelitis. Although such a &pot.
`still relies on the combination of clinical, san .
`graphic, and plain film findings, CT features [NT
`acteristic of infection include single or multiple
`questra, delineation of sinus tracts, and roe'
`,
`intraosseous (pneumatocysts)33 or soft tissuegel'
`
`Although the presence of gas always is su estivet
`!,•;
`infection, gas density in the intervertebral disc at!
`vertebral bodies in disc degeneration and vertetri
`body osteoriec-rosis (Kummell's disease), resft':
`Lively, are well known. CT also allows the physiOar:
`to choose the most appropriate site for an event'
`biopsy or aspiration (Fig. 37-5).
`Bone and Soft Tissue Neoplasms. MR imagA 1
`the preferred technique in the evaluation of to
`to!:
`o
`CT, however, remains useful in this setting-'
`able to determine (1) whether the neoplasm is hilt!,
`produces bone or cartilage, or has a nidus sr.
`rounded by bone sclerosis (osteoid °stoma/ L3th:
`fluid level (cyst, giant cell tumor, etc.); or }
`thickness of the cartilaginous cap of an osto°1-,,,,
`drama (the thicker the cap, the more likelY1'
`presence of a chondrosarcoma.)," " Soft tissue '0
`plasms are much better studied by MR. MR is, q.,„,
`sensitive but not specific for these rt.e(T,a'aie
`whereas CT is neither sensitive nor specificjirLiit
`other hand, if the presence of calcified mat° .{,r
`soft tissue neoplasm must be evaluated, the USt
`
`Figure 37-2. Pigmented viltonodular synovitis. Multiple erosions
`of the right femoral head, well demonstrated with CT, are consis•
`tent with the diagnosis of pigmented villonodular synovitis.
`
`of injury with multiplanar reformated images will
`accurately determine the extent of vertebral fractures
`and provide information on their stability, simulta-
`neous dislocation, cord compression by bone frag-
`ments in the spinal canal, and the integrity of pos-
`terior elements below and above the injured
`level.'"--"- In most instances, this information can be
`obtained rapidly, without significant risk to the pa-
`tient.
`The value of CT also is evident in the analysis
`of injuries to the pelvis and hip.23 Pelvic and sacral
`fractures often are difficult to assess on plain films,
`whereas CT depicts them and their extent with great
`precision. Particularly in the evaluation of the acetab-
`ulum, for femoral head dislocation, loose bodies, and
`
`Figure 37-3. Normal wrist. The individual musculotendinous and
`neurovascular units are well delineated on both the volar and the
`dorsal aspects. Of particular clinical importance is the optimal
`depiction of the relationships between structures beneath the
`flexor retinaculum (R) within the carpal tunnel IT) and the adjacent
`bones. (H = hamate; Fla = hamulus; C = capitate; Td =
`trapezoid; Tm (cid:9)
`trapezium.)
`
`Ex. 1029 - Page 8
`
`

`

`Donald Resnick, Marie-Josee Berthiaume, and David Sartoris • Imaging (cid:9)
`
`583
`
`contiguous slices, the use of bone and soft tissue
`window images, and coronal and sagittal reformatted
`images, although direct sagittal images' can be
`obtained with some specialized software. Direct sag-
`ittal CT has 92 percent sensitivity and 87 percent
`accuracy, for a predictive value of 93 percent in the
`diagnosis of meniscal displacement. Direct sagittal
`CT allows assessment of the range of motion, osseous
`abnormalities of the temporal eminentia and the
`mandibular condyle, joint space narrowing, meniscal
`configuration, and positional abnormalities without
`the technical problems and limitations of reconstruct-
`ing sagittal images from transaxial slices.
`Sternoclavicular Joint. The sternoclavicular joint
`can be affected by a wide variety of pathologic
`processes ranging from trauma to inflammatory or
`neoplastic diseases (Fig. 37-7). CT, when compared
`with conventional imaging techniques, is much less
`time consuming, is less uncomfortable for the pa-
`tient, and provides detailed information about the
`articulation and the surrounding soft tissues. CT
`remains the preferred examination for sternoclavic-
`ular joint disorders."
`
`A
`
`B
`Figure 37-5. A, CT-guided needle aspiration of an abscess (A)
`involving the left illacus muscle and pararivtal fossa secondary to
`septic sacroiliitis in an intravenous drug abuser. Depth (D) of
`process can be accurately determined using computer software.
`8, Tuberculosis of the sacroiliac joints. Observe the destruction of
`the left sacroiliac joint and a large cystic mass anterior to the
`articulation, representing soft tissue extension of the infection.
`
`A
`
`B
`Figure 37—t. Ankle and hindfoot disease. A. Degenerative altera-
`tions following talar fracture. Articular irregularity arid narrowing
`of the tibiotalar (Al and posterior Subtalar (B) joints are evident in
`the right foot, Multiple persistent fracture lines (F) can be identified
`within the talus (t), indicative of nonunion. 8, Talocalcaneal tarsal
`coalition. A bony bridge extending between the sustentaculum
`tali of the calcaneus and the middle facet of the talus is indicative
`of a bony coalition. Compare the appearance with that of the
`opposite normal side.
`
`CT is still recommended. Finally, CT allows accurate
`diagnostic biopsy if necessary.
`Articular Diseases. Generally, CT is not required
`for the diagnosis of articular disorders but, in some
`instances, it may be employed to define the extent
`of bone involvement in these disorders. This is par-
`ticularly true in joints that are difficult to assess by
`conventional imaging techniques, such as apophy-
`seal, costovertebral, sternoclavicular, and temporo-
`mandibular joints.
`Teniporoinimiiibufar Joint (TM]). Exquisite TMJ. an-
`atomic detail can be obtained with CT using high-
`resolution techniques and multiplanar reconstructed
`images (Fig. 37-6). Previous studies have shown
`that CT findings correlate well with arthrographic
`and surgical abnormalities. CT can demonstrate in-
`direct signs of internal derangement of the TMJ, such
`as post-traumatic alterations and meniscus disloca-
`tion.'" MR imaging, however, is actually the pre-
`ferred imaging technique for this articulation. Nev-
`ertheless, if MR is not available, CT is definitely the
`best alternative. The examination protocol should
`include open- and closed-mouth 1.5-mm tranSaxial
`
`Ex. 1029 - Page 9
`
`

`

`584 (cid:9)
`
`Diagnostic Tests and Procedures in Rheumatic Diseases • 37
`
`Figure 37-6. TemporomarKtibular joint imaging. it, Direct sit:-.1
`image of a normal articulation in the open-mouth position reFils
`the anterior (A, arrow) and posterior (P, amen} bands of thenieni;,:::
`superior to the mandibular condyle (C). The biliminar tore .7
`posterior attachment (arrowhead) is also visualized (t = teripa,.
`eminentia). 8, Direct sagittal image in the dosed-mouth pax-
`from a patient with postoperative septic arthritis demcnsliti%
`poorly defined erosions firrrirwheitolsf involving the artioofars
`of the mandibular condyle (C) and the temporal mines& iG
`Prominent periostitis (arrow) is also noted along the anteriorax7:-.
`of the condylar neck.
`
`Figure 37-7. in a patient with stern°.
`costoclavicular hyperostosis, osteo-
`sclerosis and irregular articular mar-
`gins are noted in the manubrium (M),
`associated with bone proliferation (H)
`in the soft tissues anterior to the left
`sternocostoclavicuLar joint C1)..
`
`Ex. 1029 - Page 10
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`

`Donald Resnick, Marie-Josee Berthiaume, and David Sartori; • Imaging (cid:9)
`
`585
`
`Lumbar Facet joint, Facet, or zygapophvseal,
`joints are diarthrodial synovial articulations that can
`be affected by a wide variety of diseases, including
`inflammatory and degenerative disorders,'
`trauma, and neoplasms. Cr constitutes one of the
`best imaging modalities to investigate apophyseal
`joint disorders. Because these joints have varying
`anatomic orientations at different levels, CT is partic-
`ularly well suited for their study. Furthermore, if
`necessary, reformatted sagittal, coronas, nr oblique
`views can be obtained. Standard protocols include
`nontilted transaxial contiguous 3- to 5-mm slices.
`intraspirtal synovial cysts,' which result from a
`herniation of the capsule of the apophyseal joint
`within the spinal canal, are clearly demonstrated by
`CT. They are seen as homogeneous, low-density
`posterolateral masses in the spinal canal with or
`without cord compression. These synovial cysts can
`contain a certain amount of gas. Synovial cysts have
`been seen in association with degenerative spondy-
`lolisthesis and osteoarthritis involving apophyseal
`joints with or without radicniopathy. It is important
`to note that the clinical manifestations of synovial
`cysts can mimic those of a disc herniation. CT eval-
`uation is important because it discloses the correct
`diagnosis and thus prevents unnecessary exploratory
`laminectomy. Furthermore, CT-guided infra-articular
`injection of glucocorticoids may lead to relief of
`symptoms and cause the cyst to decrease in size. [n
`patients with ankylosing spondylitis' and the cauda
`equina syndrome, careful CT examination of the
`lumbar posterior elements may reveal multiple scal-
`loped erosions involving the Laminae. These result
`from thecai diverticula (Fig. 37-8).
`Sacrothac /in The contribution of CT in the
`investigation of sacroiliac joint disorders,'R. "
`sacrolliitis,5' has been evaluated in numerous
`studies, Certain normal CT variants have been estab-
`lished by studying asymptomatic subjects prospec-
`
`lively. These studies showed asymmetry in the sa-
`croiliac joints in 77 percent of asymptomatic subjects
`over the age of 30 years and in 87 percent of those
`over 40 years of age, Poor indicators of sacroiliitis
`consist of nonuniform iliac sclerosis, focal joint space
`loss, ill-defined areas of subchondral sclerosis (mostly
`on the iliac side), and vacuum phenomena (indicative
`of lack of joint effusion). Good indicators of sacroili-
`itis include increased subchondral sclerosis in pa-
`tients under 40 years of age, unilateral or bilateral
`diffuse joint space loss (<2 mm), and erosions and
`infra-articular anky[osis. The superiority of CT over
`plain films and tomograms in the study of sacroiliitis
`is controversial. In most patients with clinical signs
`of sacroiliitis, high-quality radiographs of the sacro-
`iliac joints will be diagnostic. When CT is used,.
`however, it often will reveal that the disease is more
`advanced than had been suspected. Cr also allows
`aspiration and a rthrography of the sacroiliac joint in
`instances of suspected infection.51
`Hip. CT plays little diagnostic role in the evalu-
`ation of disorders of the hip.2 Nevertheless, CT still
`is useful in demonstrating the extent of synovial
`osteochondromatosis prior to therapy. Although CT
`had been widely used to investigate the possibility
`of osteonecrosis of the femoral head, the emergence
`of MR imaging, which is a far more sensitive and
`specific diagnostic method for ischemic necrosis, has
`led to a decline in the use of CT for this indication.
`Gfemokumeral Joint. CT, alone or combined with
`arthrogaphy, is an excellent diagnostic tool for
`shoulder trauma and specifically for instability of the
`glenohumeral joint". 51- (Fig. 37-9). For the investi-
`gation of soft tissue structures such as the rotator
`cuff, MR is the preferred imaging method.
`Knee. MR imaging is better suited than CT's to
`the evaluation of soft tissue structures, and because
`the most common pathologic processes affecting the
`knee involve the menisci and ligaments, MR imaging
`is now the best imaging method for evaluation