Ebook Bone and joint imaging (3rd edition): Part 1

(BQ) Part 1 book Bone and joint imaging presents the following contents: Basic science, diagnostic techniques, imaging and interventional procedures of the spine, imaging of the postoperative spine, rheumatoid arthritis and related diseases, connective tissue disease, degenerative diseases,...

Bone and Joint IMAGING T H I R D E D I T I O N Donald Resnick, MD Chief, Musculoskeletal Imaging Professor of Radiology University of California, San Diego San Diego, California Mark J Kransdorf, MD Chief, Musculoskeletal Imaging Mayo Clinic Jacksonville, Florida Professor of Radiology Mayo Clinic College of Medicine Rochester, Minnesota The Curtis Center 170 S Independence Mall W 300E Philadelphia, Pennsylvania 19106 BONE AND JOINT IMAGING Copyright © 2005, 1996, 1989 by Elsevier Inc ISBN 0-7216-0270-3 All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher Permissions may be sought directly from Elsevier’s Health Sciences Rights Department in Philadelphia, PA, USA: phone: (+1) 215 238 7869, fax: (+1) 215 238 2239, e-mail: healthpermissions@elsevier.com You may also complete your request on-line via the Elsevier homepage (http://www.elsevier.com), by selecting ‘Customer Support’ and then ‘Obtaining Permissions’ NOTICE Radiology is an ever-changing field Standard safety precautions must be followed, but as new research and clinical experience broaden our knowledge, changes in treatment and drug therapy may become necessary or appropriate Readers are advised to check the most current product information provided by the manufacturer of each drug to be administered to verify the recommended dose, the method and duration of administration, and contraindications It is the responsibility of the treating physician, relying on experience and knowledge of the patient, to determine dosages and the best treatment for each individual patient Neither the Publisher nor the author assumes any liability for any injury and/or damage to persons or property arising from this publication Library of Congress Cataloging-in-Publication Data Resnick, Donald Bone and joint imaging/Donald Resnick, Mark J Kransdorf – 3rd ed p.; cm Includes bibliographical references and index ISBN 0-7216-0270-3 Bones—Imaging Joints—Imaging Bones—Diseases—Diagnosis Joints—Diseases—Diagnosis I Kransdorf, Mark J II Title [DNLM: Bone Diseases—diagnosis Diagnostic Imaging—methods Joint Diseases—diagnosis WE 141 R434b 2005] RC930.5.R47 2005 616.7′10754–dc22 2003070436 Executive Editor: Allan Ross Senior Developmental Editor: Janice M Gaillard Project Manager: Linda Lewis Grigg Design Manager: Gene Harris Printed in USA Last digit is the print number: To our residents and fellows — for their motivation, enthusiasm, and, most important, inspiration CONTRIBUTORS Ronald S Adler, M.D., Ph.D Professor of Radiology, Cornell University Joan and Sanford I Weill Medical College and Graduate School of Medical Sciences; Attending Radiologist, Hospital for Special Surgery, New York, New York Diagnostic Ultrasonography Wayne H Akeson, M.D Emeritus Professor of Orthopaedics, University of California, San Diego, School of Medicine, La Jolla; Chief of Orthopaedics, Veterans Affairs San Diego Healthcare System, San Diego, California Articular Cartilage: Morphology, Physiology, and Function Robert Downey Boutin, M.D Executive Musculoskeletal Radiologist, Med-Tel International, McLean, Virginia Muscle Disorders William Bugbee, M.D Assistant Professor, Department of Orthopaedics, University of California, San Diego, School of Medicine, La Jolla, California Articular Cartilage: Morphology, Physiology, and Function Constance R Chu, M.D Assistant Professor, University of Pittsburgh School of Medicine; Director, Cartilage Restoration, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania Articular Cartilage: Morphology, Physiology, and Function Christine B Chung, M.D Assistant Professor of Radiology, University of California, San Diego, School of Medicine, La Jolla; Department of Radiology, Veterans Affairs San Diego Healthcare System, San Diego, California Developmental Dysplasia of the Hip James M Coumas, M.D Musculoskeletal Radiologist, Carolina Hospital Authority, Charlotte, North Carolina Interventional Spinal Procedures Murray K Dalinka, M.D Professor of Radiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania Jerry R Dwek, M.D Assistant Clinical Professor, University of California, San Diego, School of Medicine, La Jolla; Department of Orthopaedic Surgery, Veterans Affairs San Diego Healthcare System, San Diego, California Developmental Dysplasia of the Hip Michael D Fallon, M.D.* Former Assistant Professor of Pathology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania *deceased Histogenesis, Anatomy, and Physiology of Bone Frieda Feldman, M.D Professor of Radiology, Columbia College of Physicians and Surgeons; Attending Radiologist, New York Presbyterian Hospital, New York, New York Tuberous Sclerosis, Neurofibromatosis, and Fibrous Dysplasia Steven R Garfin, M.D Chairman, Department of Orthopaedic Surgery, University of California, San Diego, University of California, San Diego, Medical Center, San Diego, California Imaging after Spinal Surgery Thomas G Goergen, M.D Associate Clinical Professor, University of California, San Diego, School of Medicine, La Jolla; Palomar Medical Center, Escondido, California Physical Injury: Concepts and Terminology Amy Beth Goldman, M.D New York, New York Heritable Diseases of Connective Tissue, Epiphyseal Dysplasias, and Related Conditions Guerdon D Greenway, M.D Associate Clinical Professor, Department of Radiology, University of California, San Diego, School of Medicine, La Jolla, California; Clinical Associate Professor, Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas; Attending Physician, Department of Radiology, Baylor University Medical Center, Dallas, Texas Tumors and Tumor-like Lesions of Bone: Imaging and Pathology of Specific Lesions Radiation Changes v vi Contributors W Bonner Guilford, M.D Musculoskeletal Radiologist, Charlotte Radiology, Carolina Healthcare System, Charlotte, North Carolina Interventional Spinal Procedures Parviz Haghighi, M.D., F.R.C.P.A Professor of Clinical Pathology, University of California, San Diego; Staff Pathologist, Veterans Affairs Medical Center, San Diego, California Lymphoproliferative and Myeloproliferative Disorders Tamara Miner Haygood, M.D., Ph.D Radiology Associates, Corpus Christi, Texas Radiation Changes Thomas E Herman, M.D Associate Professor, Mallinckrodt Institute of Radiology and Washington University School of Medicine; Radiologist, St Louis Children’s Hospital, St Louis, Missouri Osteochondrodysplasias, Dysostoses, Chromosomal Aberrations, Mucopolysaccharidoses, and Mucolipidoses Brian A Howard, M.D., M.B.C.H.B Musculoskeletal Radiologist, Charlotte Radiology, Carolina Healthcare System, Charlotte, North Carolina Interventional Spinal Procedures Phoebe A Kaplan, M.D Montreal, Quebec, Canada Temporomandibular Joint Michael Kyriakos, M.D Professor of Surgical Pathology, Washington University School of Medicine; Senior Pathologist, Barnes Hospital, St Louis, Missouri Tumors and Tumor-like Lesions of Bone: Imaging and Pathology of Specific Lesions Laurence A Mack, M.D.* Former Professor of Radiology, Adjunct Professor of Orthopedics, and Director of Ultrasound, University of Washington, Seattle, Washington *deceased Diagnostic Ultrasonography John E Madewell, M.D Professor of Radiology and Director of Clinical Radiology Operations, University of Texas M D Anderson Cancer Center, Houston, Texas Osteonecrosis: Pathogenesis, Diagnostic Techniques, Specific Situations, and Complications Stavros C Manolagas, M.D., Ph.D Professor of Medicine and Director, Division of Endocrinology and Metabolism, University of Arkansas for Medical Sciences, Little Rock, Arkansas Histogenesis, Anatomy, and Physiology of Bone William H McAlister, M.D Professor of Radiology and Pediatrics, Washington University School of Medicine and Mallinckrodt Institute of Radiology; Radiologist-in-Chief, St Louis Children’s Hospital, St Louis, Missouri Osteochondrodysplasias, Dysostoses, Chromosomal Aberrations, Mucopolysaccharidoses, and Mucolipidoses William A Murphy, Jr., M.D John S Dunn, Sr., Distinguished Chair and Professor of Radiology, University of Texas M D Anderson Cancer Center, Houston, Texas Temporomandibular Joint M B Ozonoff, M.D Salt Lake City, Utah Spinal Anomalies and Curvatures Mini N Pathria, M.D Professor of Clinical Radiology, University of California, San Diego, School of Medicine, La Jolla, California Imaging after Spinal Surgery; Physical Injury: Spine Michael J Pitt, M.D Professor of Radiology, University of Alabama School of Medicine; Staff, University Hospital, UAB Children’s Hospital of Alabama, Birmingham, Alabama Rickets and Osteomalacia Jeffrey S Ross, M.D Head, Radiology Research, and Staff Neuroradiologist, Cleveland Clinic Foundation, Cleveland, Ohio Spinal Imaging David A Rubin, M.D Associate Professor of Radiology, Washington University School of Medicine; Director, Musculoskeletal Section, Mal&linckrodt Institute of Radiology, St Louis, Missouri Magnetic Resonance Imaging: Practical Considerations David J Sartoris, M.D.* Former Professor of Radiology, University of California, San Diego; Chief, Quantitative Bone Densitometry, UCSD Medical Center; Professor of Radiology, Veterans Affairs Medical Center and Scripps Clinic, Green Hospital, La Jolla, California *deceased Developmental Dysplasia of the Hip F William Scheible, M.D Radiology Consultants of Iowa, Cedar Rapids, Iowa Diagnostic Ultrasonography Robert Schneider, M.D Associate Professor of Radiology, Cornell University Joan and Sanford I Weill Medical College and Graduate School of Medical Sciences; Attending Radiologist, Hospital for Special Surgery, New York, New York Radionuclide Techniques Contributors Carolyn M Sofka, M.D Associate Professor of Radiology, Cornell University Joan and Sanford I Weill Medical College and Graduate School of Medical Sciences; Assistant Attending Radiologist, Hospital for Special Surgery, New York, New York Diagnostic Ultrasonography Donald E Sweet, M.D.* Former Clinical Professor of Pathology, Georgetown University School of Medicine, Washington, D.C.; Clinical Professor of Pathology, Uniformed Services University of Health Sciences, Bethesda, Maryland; Chairman, Department of Orthopedic Pathology, Armed Forces Institute of Pathology, Washington, D.C *deceased Osteonecrosis: Pathogenesis, Diagnostic Techniques, Specific Situations, and Complications Barbara N Weissman, M.D vii Professor of Radiology, Harvard Medical School; Vice Chair for Ambulatory Services, Brigham and Women’s Hospital, Boston, Massachusetts Imaging after Surgery in Extraspinal Sites; Imaging of Joint Replacement PREFACE Nine years after the publication of the second edition of Bone and Joint Imaging and a few years after the publication of the fourth edition of the larger Diagnosis of Bone and Joint Disorders, the third edition of Bone and Joint Imaging is now ready for dissemination In common with the first and second editions of this text, the purpose of this book is to present in a logical manner and easy-to-read format the information that we, the authors, believe is essential for those learning musculoskeletal imaging for the first time or for those reviewing the subject one more time The subject of musculoskeletal imaging is ever changing and constantly growing in scope Much of this growth relates not to the discovery of new processes or disorders but rather to the development and refinement of advanced imaging methods and techniques Diagnostic methods now applied routinely to the analysis of musculoskeletal disorders include far more than conventional radiography: CT scanning, MR imaging, ultrasonography, radionuclide studies, and arthrography are among the additional methods that must be mastered by those interpreting images related to bone, joint, and soft tissue disorders To summarize adequately the many imaging techniques and findings in a text any shorter than this, in our view, would not be appropriate or even possible The organization of the text follows that of the previous edition Basic anatomy and physiology, diagnostic tech- niques, and postoperative imaging serve as introductory material; this material is then followed by sections dealing with imaging of most of the important diseases that affect the musculoskeletal system Key images have been selected to illustrate the most important of the imaging findings, and a short but appropriate bibliography is included in each chapter As before, we have included shortened versions of many chapters written by experts in the field that were part of the larger multivolume textbook When compared with the second edition, however, there are significant changes in this third edition Many subjects appear for the first time, countless new and improved illustrations are included, and references are updated And to this properly and on time, two editors rather than one have accomplished this task Both of us are confident that we have succeeded in condensing the essential material related to musculoskeletal imaging in a manageable textbook But it is the readers who are the ultimate judge We are hopeful that whether it is used for consultation on an intermittent basis or read in its entirety, the readers will enjoy the experience and be wiser for it DONALD RESNICK MARK J KRANSDORF ix ACKNOWLEDGMENTS We are greatly indebted to a number of individuals without whom this project would not be possible This includes our many contributing authors, all of whom are highly regarded educators and experts in their respective fields Their efforts are very much appreciated A very special thanks must go to Allan Ross, Executive Editor, and his associates at Elsevier: Janice M Gaillard, Senior Developmental Editor; Linda Lewis Grigg, Project Manager, Book Production; and Walter Verbitski, Illustration Specialist x We would also like to acknowledge those individuals whose dedication, commitment, and energy often go unnoticed but who keep the system running smoothly and on time: our administrative assistants Michael Holbrook, Debra Trudell, and Pamela J Chirico Basic Science I SECTION CHAPTER Histogenesis, Anatomy, and Physiology of Bone Donald Resnick, Stavros C Manolagas, and Michael D Fallon SUMMARY OF KEY FEATURES Bone is a unique tissue that is constantly undergoing change It develops through the processes of endochondral and intramembranous ossification and is subsequently modified and refined by the processes of modeling and remodeling to create a structurally and metabolically competent, highly organized architectural marvel Its cells, including osteoblasts, osteocytes, and osteoclasts, reside in organic matrix, primarily collagen, and inorganic material is deposited in a form that resembles hydroxyapatite The process of mineralization is complex and incompletely understood Bone is essential in maintaining calcium homeostasis, or stabilization of the plasma level of calcium Its cells are highly responsive to stimuli provided by a number of humoral agents, the most important of which are parathyroid hormone, thyrocalcitonin, and 1,25dihydroxyvitamin D Synthesis and resorption of bone, which normally continue in a delicate balance throughout life, are mediated by the action of such humoral agents through processes that include stimulation of osteoblasts to form bone and stimulation of osteoclasts to remove bone INTRODUCTION Bone is a remarkable tissue Although its appearance on radiographs might be misinterpreted as indicating inactivity, bone is constantly undergoing change This occurs not only in the immature skeleton, in which growth and development are readily apparent, but also in the mature skeleton, through the constant and balanced processes of bone formation and resorption It is when these processes are modified such that one dominates, that a pathologic state may be created In some instances, the resulting imbalance between bone formation and resorption is easily detectable on the radiograph In others, a more subtle imbalance exists that may be identified only at the histologic level The initial architecture of bone is characterized by an irregular network of collagen, termed woven-fibered bone, which is a temporary material that is either removed to form a marrow cavity or subsequently replaced by a sheetlike arrangement of osseous tissue, termed parallelfibered, or lamellar, bone As a connective tissue, bone is highly specialized and differs from other connective tissue by its rigidity and hardness, which relate primarily to the inorganic salts that are deposited in its matrix These properties are fundamental to a tissue that must maintain the shape of the human body, protect its vital soft tissues, and allow locomotion by transmitting from one region of the body to another the forces generated by the contractions of various muscles Bone also serves as a reservoir for ions, principally calcium, that are essential to normal fluid regulation; these ions are made available as a response to stimuli produced by a number of hormones, particularly parathyroid hormone, vitamin D, and calcitonin HISTOGENESIS Developing Bone Bone develops by the process of intramembranous bone formation (transformation of condensed mesenchymal tissue), endochondral bone formation (indirect conversion of an intermediate cartilage model), or both At some locations, such as the bones of the cranial vault (frontal and parietal bones, as well as parts of the occipital and temporal bones), the mandible and maxilla, and the midportion of the clavicle, intramembranous (mesenchymal) ossification is detected; in other locations, such as the bones of the extremities, the vertebral column, the pelvis, and the base of the skull, both endochondral and intramembranous ossification can be identified The actual processes of bone tissue formation are essentially the same in both intramembranous and endochondral ossification and include the following sequence: (1) osteoblasts differentiate from mesenchymal cells; (2) osteoblasts deposit matrix, which is subsequently mineralized; (3) bone is initially deposited as a network of immature (woven) trabeculae, the primary spongiosa; and (4) the primary spongiosa is replaced by secondary bone, removed to form bone marrow, or converted to primary cortical bone by the filling of spaces between trabeculae Intramembranous Ossification Intramembranous ossification is initiated by the proliferation of mesenchymal cells about a network of capillaries At this site, transformation of the mesenchymal cells is accompanied by the appearance of a meshwork of collagen fibers and amorphous ground substance The primitive cells proliferate, enlarge, and become arranged in groups, transforming into osteoblasts, which are intimately involved in the formation of an eosinophilic matrix within the collagenous tissue As the osteoid matrix undergoes calcification with the deposition of calcium phosphate, some of the osteoblasts on the surface of the osteoid and +, common; – uncommon or rare Diffuse sclerosis Focal sclerosis Osteopenia or bone lysis Bony enlargement Osteophytosis, ligament ossification Splenomegaly Distribution Axial > appendicular + + + – – + – – Mastocytosis Axial > appendicular + + + – Skeletal Metastasis Differential Diagnosis of Osteosclerosis TABLE 51–3 – + Axial > appendicular + – + – Myelofibrosis – + Axial > appendicular + + + – Lymphomas – – Axial > appendicular + + + + Paget’s Disease + – Axial > appendicular + – – – Fluorosis – – Axial > appendicular + – + – Renal Osteodystrophy – – + – – – Axial Axial Osteomalacia Chapter 51 Lymphoproliferative and Myeloproliferative Disorders the appearance of osteoporosis, sickle cell anemia, Gaucher’s disease, and plasma cell myeloma Diffuse osteosclerosis is observed not only in systemic mastocytosis but also in myelofibrosis, skeletal metastasis, fluorosis, Paget’s disease, renal osteodystrophy, and numerous other conditions The multiple focal osteosclerotic lesions in systemic mastocytosis resemble the findings in skeletal metastasis and tuberous sclerosis POLYCYTHEMIA VERA General Features Polycythemia vera (primary polycythemia), a disease of unknown cause characterized by hyperplasia of all the cellular elements in the bone marrow (primarily erythrocytes), results in an elevated red blood cell count, leukocytosis, and thrombocytosis Polycythemia vera occurs in middle-aged or elderly patients Clinical complaints include headache, dizziness, weakness, fatigue, paresthesias, dyspnea, and visual disturbances On physical examination, a ruddy complexion, hepatosplenomegaly, and systolic hypertension are seen Vascular thrombosis is a recognized complication of the disease that is related to thrombocytosis and increased blood viscosity Occlusion of hepatic veins (Budd-Chiari syndrome) and cirrhosis of the liver may be evident In the later stages of the disease, myelofibrosis, progressive myeloid metaplasia, and anemia are encountered Musculoskeletal Abnormalities Vascular thrombosis can lead to osteonecrosis, particularly of the femoral head, and generalized marrow hyperplasia can produce patchy radiolucent lesions throughout the bone The cranial abnormalities may resemble those of thalassemia major Myelofibrosis is associated with generalized increased radiodensity of the skeleton Extramedullary hematopoiesis is seen in later stages of the disease Hyperuricemia is not infrequent in (primary) polycythemia vera or secondary polycythemia Gouty arthritis has been estimated to occur in 5% to 8% of all cases MYELOFIBROSIS General Features Myelofibrosis is an uncommon disease associated with fibrotic or sclerotic bone marrow and extramedullary hematopoiesis Its cause has not been precisely determined Myelofibrosis is usually divided into two forms: primary (or idiopathic) and secondary The basic pathologic finding is fibrosis of the bone marrow, which in some instances may replace almost the entire marrow tissue Focal or diffuse areas of hypercellular marrow may be combined with trabecular thickening and overgrowth The degree of bone marrow fibrosis is generally thought to indicate the severity of the disease process Clinical Abnormalities Myelofibrosis is usually a disease of middle-aged and elderly men and women Most affected patients are in 699 the sixth or seventh decade of life The disease is generally insidious in onset Symptoms include weakness, fatigue, weight loss, abdominal pain, anorexia, nausea, vomiting, and dyspnea Physical signs may include abdominal swelling, hepatosplenomegaly, and purpura Hematologic evaluation frequently reveals moderate to severe anemia, an increased number of nucleated red blood cells, leukocytosis, or leukopenia The diagnosis is established by bone marrow biopsy The prognosis of the disease is variable Some patients die within a few months of the initial diagnosis, whereas others survive for a prolonged time Musculoskeletal Abnormalities The radiographic picture reflects the pathologic changes In some instances, normal or osteopenic bone and osteolytic lesions are observed, but in general, osteosclerosis is the predominant radiographic pattern and is observed in 40% to 50% of patients in both the axial skeleton and the proximal ends of the long bones (Fig 51–15) The bones altered most commonly are the spine, pelvis, skull, ribs, proximal end of the humerus, and proximal portion of the femur The osseous structures may be uniformly dense or demonstrate small areas of relative radiolucency In the long bones, cortical thickening may be observed and is predominantly due to endosteal sclerosis This abnormality results in obliteration of the normal demarcation between cortical and medullary bone In the spine, increased radiodensity or condensation of bone at the superior and inferior margins of the vertebral body (sandwich vertebrae) may be encountered Extramedullary hematopoiesis in this condition can create lobulated, paravertebral intrathoracic masses Articular Abnormalities Hemarthrosis has been described in association with myeloproliferative disease and can be its initial manifestation Impaired platelet function presumably contributes to the bleeding episodes Fifty percent to 80% of patients have elevated serum or urinary uric acid levels Secondary gout, which may antedate the diagnosis of myelofibrosis, occurs in 5% to 20% of patients and may be associated with tophi and renal uric acid stones The polyarthralgias and polyarthritis in myelofibrosis may resemble rheumatoid arthritis Magnetic Resonance Imaging Fibrotic replacement of the marrow, when examined with standard spin echo MR sequences, is characterized by decreased signal intensity on both T1- and T2-weighted images Regions of intermediate to high signal intensity at sites of marrow involvement have been described with STIR imaging and after intravenous gadolinium administration A focal or diffuse pattern of alteration in signal intensity may be encountered MR imaging abnormalities are evident in the vertebrae, pelvis, and ribs (Fig 51–16) Subsequent pathologic events, such as reconversion from fatty to hematopoietic marrow and marrow fibrosis, occur in the tubular bones, especially the femur, humerus, and 700 Section XIII Diseases of the Hematopoietic System Figure 51–15 Myelofibrosis: radiographic abnormalities Patchy osteosclerosis of the entire pelvis is associated with small radiolucent areas The spleen is enlarged (arrow) tibia, and they account for the same pattern of signal abnormality encountered in the axial skeleton In-phase and chemical shift opposed-phase spin echo MR sequences may be a useful adjunct in evaluating the presence of nonfatty marrow in the femoral neck and intertrochanteric region, findings considered abnormal in middle-aged and elderly individuals Differential Diagnosis Figure 51–16 Myelofibrosis: MR imaging abnormalities in the axial skeleton On a coronal T1-weighted (TR/TE, 650/30) spin echo MR image of the pelvis, the marrow of the vertebral bodies, pelvic bones, and proximal ends of the femora is predominantly low in signal intensity This pattern is consistent with the presence of hematopoietic marrow or fibrosis Schmorl’s nodes are evident, and the spleen is enlarged (Courtesy of T Mattsson, MD, Riyadh, Saudi Arabia.) The radiographic diagnosis of myelofibrosis should be suggested when axial skeleton osteosclerosis is combined with splenomegaly in a middle-aged or elderly patient (see Table 51–3) Although lymphoma and leukemia can lead to splenomegaly, the extent of the bone sclerosis is less in these conditions than in myelofibrosis Systemic mastocytosis can produce diffuse or focal osteosclerosis and hepatosplenomegaly, and it may be difficult to distinguish this condition from myelofibrosis Increased radiodensity of bone without splenic enlargement may be seen in some patients with myelofibrosis and is apparent in patients with this disorder who have had splenectomies This combination of findings may be evident in other processes as well, including skeletal metastasis, fluorosis, Paget’s disease, axial osteomalacia, and renal osteodystrophy Differentiation of myelofibrosis and skeletal metastasis can be difficult In most cases, the sclerosis observed in metastatic disease of the bone is less generalized, less symmetrical, and more frequently associated with osteolytic lesions In fluorosis, spinal osteophytosis, ligament calcification and ossification, and periostitis may be noted In renal osteodystrophy, other changes are evident, including those of hyperparathyroidism In Paget’s disease, a characteristic coarsened trabecular pattern is present Chapter 51 Lymphoproliferative and Myeloproliferative Disorders BONE MARROW TRANSPLANTATION Bone marrow transplantation is a technique for replenishing the bone marrow with normal pluripotential stem cells Normal marrow cells from a histocompatible allogeneic donor are used to repopulate the diseased marrow, and such transplantation is frequently combined with intensive chemotherapy or immunosuppressive therapy The marrow is usually obtained from the donor’s iliac crest Infections developing immediately before or soon after bone marrow transplantation relate to the effects of chemotherapy and radiation therapy, as well as the transplantation itself Bacterial and fungal infections dominate in the pretransplantation period, and viral infections may also be encountered During the first or weeks after transplantation, severe granulocytopenia, fever, and, in about 50% of patients, at least one episode of bacteremia are seen Neutropenia at this time predisposes to infections caused by opportunistic organisms Delayed post-transplantation infections are usually related to varicella-zoster virus or recurrent bacterial or fungal infections Graft-versus-host disease, which is discussed in detail in Chapter 24, is believed to be the result of allogeneic T cells that were transfused with the graft or that developed from its reaction to targets of the genetically different host An immunologic attack on the recipient’s tissues develops Acute graft-versus host disease occurs within the first months after transplantation and is associated with lesions of the skin, liver, and gastrointestinal tract Specific clinical findings include an erythematous maculopapular skin rash on the face, trunk, and extremities, as well as abdominal pain, diarrhea, nausea, and vomiting Chronic graft-versus-host disease affects 20% to 40% of patients who survive more than months after transplantation It involves the skin, oral mucosa, serosal surfaces, skeletal muscle, gastrointestinal tract, liver, and lung, and its manifestations resemble those of a collagen vascular disorder, particularly scleroderma Chemotherapy and radiotherapy administered in the pretransplantation period are designed not only to induce immunologic suppression in the recipient but also to eliminate any residual malignant cell populations The initial response of the bone marrow to such therapy is congestion and edema Subsequently, hematopoietic tissue disappears, and the marrow becomes predominantly fatty High signal intensity is observed on T1-weighted spin echo MR images, and intermediate signal intensity is seen on T2-weighted spin echo images, signal characteristics that are typical of adipose tissue During transplantation, bone marrow cells are infused intravenously After transient residence in the lungs and spleen, the infused stem cells migrate to the bone marrow Hematologic engrafting typically takes to weeks and is heralded by a peripheral rise in granulocytes Repopulation of the bone marrow in the spine after transplantation can be studied with MR imaging On T1-weighted spin echo MR images, the superior and inferior margins of the vertebral bodies reveal low signal intensity, whereas the central portion of the vertebral bodies show high signal intensity, consistent with fat With STIR sequences, the 701 opposite situation is apparent, with high signal intensity at the superior and inferior vertebral margins and low signal intensity centrally At histologic examination, the marginal, or peripheral, regions of the vertebral body are found to contain a concentrated collection of repopulating cells, and the central region contains predominantly marrow fat FURTHER READING Amano Y, Onda M, Amano M, et al: Magnetic resonance imaging of myelofibrosis: STIR and gadolinium-enhanced MR images Clin Imaging 21:264, 1997 Avila NA, Ling A, Metcalfe D, et al: Mastocytosis: Magnetic resonance imaging pattern of marrow disease Skeletal Radiol 27:119, 1998 Bloch KJ, Buchanan WW, Whol MJ, et al: Sjögren’s syndrome: A clinical, pathological and serological study of sixty-two cases Medicine 44:187, 1965 Braunstein EM, White SJ: Non-Hodgkin’s lymphoma of bone Radiology 135:59, 1980 Chew FS, Schellingerhout D, Keel SB: Primary lymphoma of skeletal muscle AJR Am J Roentgenol 172:1370, 1999 Coles WC, Schulz MD: Bone involvement in malignant lymphoma Radiology 50:458, 1948 Dalinka MK: Primary lymphoma of bone: Radiographic appearance and prognosis Radiology 147:288, 1983 Demanes DJ, Lane N, Beckstead JH: Bone involvement in hairy-cell leukemia Cancer 49:1697, 1982 Ferris RA, Hakkai HG, Cigtay OS: Radiologic manifestations of North American Burkitt’s lymphoma AJR Am J Roentgenol 123:614, 1975 Glatt W, Weinstein A: Acropachy in lymphatic leukemia Radiology 92:125, 1969 Harris NL, Jaffe ES, Diebold J, et al: World Health Organization classification of neoplastic diseases of the hematopoietic and lymphoid tissues: Report of the clinical advisory committee meeting−Airlie House, Virginia, November 1997 J Clin Oncol 17:3835, 1999 Kaplan KR, Mitchell DG, Steiner RM, et al: Polycythemia vera and myelofibrosis: Correlation of MR imaging, clinical, and laboratory findings Radiology 183:329, 1992 Lecouvet FE, Dechambre S, Malghem J, et al: Bone marrow transplantation in patients with multiple myeloma: Prognostic significance of MR imaging AJR Am J Roentgenol 176:91, 2001 Leigh TF, Corley CC Jr, Huguley CM Jr, et al: Myelofibrosis: The general and radiologic findings in 25 proven cases AJR Am J Roentgenol 82:183, 1959 McKenna MJ, Frame B: The mast cell and bone Clin Orthop 200:226, 1985 Metzler JP, Fleckenstein JL, Vuitch F, et al: Skeletal muscle lymphoma: MRI evaluation Magn Reson Imaging 10:491, 1992 Neiman RS, Barcos M, Berard C, et al: Granulocytic sarcoma: A clinicopathologic study of 61 biopsied cases Cancer 48:1426, 1981 Nixon GW, Gwinn JL: The roentgen manifestations of leukemia in infancy Radiology 107:603, 1973 Olson DO, Schields AF, Scheurich CJ, et al: Magnetic resonance imaging of the bone marrow in patients with leukemia, aplastic anemia, and lymphoma Invest Radiol 21:540, 1986 O’Reilly GV, Clark TM, Crum CP: Skeletal involvement in mycosis fungoides AJR Am J Roentgenol 129:741, 1977 702 Section XIII Diseases of the Hematopoietic System Parker BR, Marglin S, Castellino RA: Skeletal manifestations of leukemia, Hodgkin disease and non-Hodgkin lymphoma Semin Roentgenol 15:302, 1980 Patzik SB, Smith C, Kubicka RA, et al: Bone marrow transplantation: Clinical and radiologic aspects Radiographics 11:601, 1991 Pettigrew JD, Ward HP: Correlation of radiologic, histologic and clinical findings in agnogenic myeloid metaplasia Radiology 93:541, 1969 Phillips WC, Kattapuram SV, Doseretz DE, et al: Primary lymphoma of bone: Relationship of radiographic appearance and prognosis Radiology 144:285, 1982 Poppel MH, Gruber WF, Silber R, et al: The roentgen manifestations of urticaria pigmentosa (mastocytosis) AJR Am J Roentgenol 82:239, 1959 Rafii M, Firooznia H, Golimbu C, et al: Pathologic fracture in systemic mastocytosis: Radiographic spectrum and review of the literature Clin Orthop 180:260, 1983 Schabel SI, Tyminski L, Holland RD, et al: The skeletal manifestations of chronic myelogenous leukemia Skeletal Radiol 5:145, 1980 Schwartz AM, Leonidas JC: Methotrexate osteopathy Skeletal Radiol 11:13, 1984 Silbiger ML, Peterson CC Jr: Sjögren’s syndrome: Its roentgenographic features AJR Am J Roentgenol 100:554, 1967 Simmons CR, Harle TS, Singleton EB: The osseous manifestations of leukemia in children Radiol Clin North Am 6:115, 1968 Talbott JH: Gout and blood dyscrasias Medicine 38:173, 1959 Vogler JB III, Murphy WA: Bone marrow imaging Radiology 168:679, 1988 White LM, Schweitzer ME, Khalili K, et al: MR imaging of primary lymphoma of bone: Variability of T2-weighted signal intensity AJR Am J Roentgenol 170:1243, 1998 CHAPTER 52 Bleeding Disorders SUMMARY OF KEY FEATURES The skeletal abnormalities associated with hemophilia and other bleeding diatheses are characteristic They result from hemorrhage in soft tissue, muscle, and subperiosteal, intraosseous, and intra-articular locations In involved joints, typical findings are radiodense effusions, regional or periarticular osteoporosis, subchondral bony erosions and cysts, and joint space narrowing Hyperemia may lead to epiphyseal overgrowth in a child affected by these disorders Tumor-like lesions are occasionally encountered that are due to massive subperiosteal, osseous, or soft tissue hemorrhage, with erosion and distortion of adjacent bone Hemosiderin deposition in any of these disorders leads to characteristic findings on magnetic resonance imaging The differential diagnosis is usually not difficult when both clinical and imaging features are studied INTRODUCTION Hemophilia is a term applied to a group of disorders characterized by an anomaly of blood coagulation caused by a deficiency in a specific plasma clotting factor This anomaly leads to easy bruising and prolonged and excessive bleeding Of these disorders, two are associated most commonly with intraosseous and intra-articular bleeding: classic hemophilia (hemophilia A), characterized by a functional deficiency of antihemophilic factor (factor VIII), and Christmas disease (hemophilia B), marked by a functional deficiency of plasma thromboplastin component (factor IX) These two types of hemophilia are X-linked recessive disorders that are clinically manifested in men and carried by women Rarely, other disorders of blood coagulation may manifest as bone and joint abnormalities One such disorder is von Willebrand’s disease, a rare familial disease of both men and women that apparently is attributable to a dominant autosomal mutant gene; in this disease, both factor VIII and functional platelet abnormalities occur HEMOPHILIA Clinical Abnormalities Classic hemophilia occurs in approximately of every 10,000 men and boys in the United States Christmas disease occurs about one tenth as often as classic hemophilia Although both forms are confined almost exclusively to male subjects, reports exist of significant clinical and radiographic abnormalities in female patients The severity of the clinical manifestations in either form of hemophilia varies In mild forms of disease, excessive 52 bleeding may be apparent only during surgery With moderate or severe forms, bleeding episodes may also occur spontaneously or after minor or significant trauma The diagnosis is established by performing appropriate laboratory tests to detect defects in blood coagulation Hemarthrosis is a particularly characteristic abnormality, occurring in approximately 75% to 90% of patients It may begin in the early years of life, and young children and adolescents demonstrate more frequent episodes of joint bleeding than adults The joints altered most commonly are the knee, elbow, ankle, hip, and glenohumeral joint, in descending order of frequency Joints such as the knee, whose stability depends on adjacent soft tissue structures rather than intrinsic factors, are particularly vulnerable Usually a single joint is involved in each episode, although eventually multiple joints are affected Joint involvement may be markedly asymmetrical or even unilateral Clinical manifestations of hemophilic arthropathy can be divided into three types, although they are not rigidly defined: Acute hemarthrosis Joint bleeding may occur rapidly, producing a tense, swollen, red, and tender articulation that is painful and stiff Associated muscle spasm leads to flexion of the extremity and restricted motion Symptoms decrease quickly after administration of the appropriate clotting factor Subacute hemarthrosis After multiple acute episodes, complete recovery of the joint is not evident Joint motion is restricted, a finding that appears to best correlate with the degree of cartilaginous destruction, and contractures and muscle atrophy become evident Chronic hemarthrosis After months to year, a chronic stage may develop More severe and persistent contractures are found, particularly in the elbow and knee The final stage is a fibrotic, contracted, and destroyed joint Approximately 50% of hemophilic patients develop permanent changes in the peripheral joints Articular bleeding may be accompanied by hemorrhage into muscles, fascial planes, and bones Soft tissue bleeding can lead to fixed joint deformities and soft tissue necrosis Compartment syndromes may complicate intramuscular bleeding in the upper or lower extremities The most common of these in hemophilia are Volkmann’s contractures, related to massive hemorrhage into the volar muscles of the forearm Hemorrhage in and around the spinal cord can lead to neurologic abnormalities Subperiosteal and intraosseous bleeding can induce trabecular distortion and destruction, and large expansile lesions, particularly of the femur and ilium (hemophilic pseudotumors), may simulate neoplasm Pathologic Abnormalities After an acute episode of intra-articular bleeding, blackish fluid containing clots is apparent With each recurring 703 704 Section XIII Diseases of the Hematopoietic System episode of bleeding, resorption of blood is less complete and more permanent findings are apparent, particularly in the synovial membrane, with brownish discoloration caused by the absorption of blood pigment Synovial villi become more numerous and enlarged, and the entire membrane thickens The subsynovial tissue undergoes dense fibrous proliferation Marginal cartilaginous erosion appears adjacent to synovial pannus, and eventually numerous small or large serrated erosions are scattered throughout the cartilaginous surface Loss of the subchondral bone plate occurs, so that the calcified layer of cartilage rests on the cancellous bone Trabecular thinning and resorption lead to enlarging subchondral cysts Osseous cystic lesions are particularly prominent in this disease Productive changes may appear, with sclerotic trabeculae and osteophytes (Table 52–1; Fig 52–1) Massive periosteal or intraosseous hemorrhage creates neoplastic-like lesions called hemophilic pseudotumors (Fig 52–2) In subperiosteal locations, the periosteal membrane is lifted from the parent bone, and hemorrhage may extend into the adjacent soft tissues Periosteal bone formation follows, creating expanded and irregular osseous contours In intraosseous locations, large defects with geographic (relatively well-defined) bone destruction may be seen In the immature skeleton, chronic hyperemia of the epiphyseal cartilage can produce accelerated maturation and enlargement of epiphyses A B C D Radiographic Abnormalities General Features The findings of hemophilia have been divided into five stages on the basis of a variety of radiographic abnormalities: (1) soft tissue swelling, (2) osteoporosis, (3) osseous subchondral cystic lesions, (4) narrowing of the interosseous space with cartilage destruction, and (5) joint disorganization with severe cartilaginous and osseous abnormalities The division of the radiographic changes into stages E Figure 52–1 Hemophilia: pathologic abnormalities—intraTABLE 52–1 Hemophilia: Radiographic-Pathologic Correlation Pathology Radiology Recurrent intra-articular hemorrhage with hemosiderinladen hypertrophied synovial membrane Synovial inflammation and pannus formation; hyperemia Radiodense joint effusions Cartilaginous erosion; subchondral trabecular resorption and collapse Cartilaginous denudation Bony proliferation Soft tissue, superiosteal, and intraosseous hemorrhage Osteoporosis; epiphyseal overgrowth; accelerated skeletal maturation Bony erosions and cysts Joint space narrowing Sclerosis and osteophytosis Pseudotumors articular findings A, Acute episodes of bleeding lead to accumulation of blood in the articular cavity and periarticular soft tissues B, After numerous bleeding episodes, absorption of blood is incomplete from the articular cavity and soft tissues Brownish discoloration of the synovial membrane is associated with hypertrophy and hyperemia Synovial inflammatory tissue, or pannus, appears at the margins of the articular cartilage (arrows) C, At a later stage, periarticular osteoporosis and focal areas of cartilage and osseous destruction become apparent Cystic lesions are evident, which generally communicate with the joint cavity Note areas of relatively normal cartilage and bone D, Continued destruction of cartilage and bone leads to enlarging cystic lesions, surface irregularities, osteoporosis, and joint space narrowing E, In late stages of the disease, fibrous adhesions extend across the articular space New episodes of bleeding occur (see Fig 52–1) does not imply that all cases follow this sequence of events Further, radiographic abnormalities not always develop in a systematic fashion Although bone change usually precedes cartilage loss, this is not Chapter 52 Bleeding Disorders 705 Distribution of Abnormalities The knee, ankle, and elbow are the joints involved most frequently Bilateral involvement is common, but the changes need not be symmetrical A Knee The knee is affected most often (Fig 52–3) Dense joint effusions are common Periarticular osteoporosis creates lucent epiphyses of both the distal end of the femur and the proximal part of the tibia Irregularity of the articular surface of the femoral condyles, the tibial plateaus, and the posterior surface of the patella may become apparent Multiple subchondral cysts are frequent and sometimes grow to a large size Overgrowth of the distal femoral and proximal tibial epiphyses may result The distal condylar surface may appear flattened, and the intercondylar notch of the femur is commonly widened Squaring of the inferior pole of the patella has been detected in as many as 20% to 30% of patients with hemophilia However, squaring of the patella is not specific for hemophilia, being a recognized manifestation of juvenile chronic arthritis Differentiation between these two disorders on the basis of knee radiographs is very difficult B Figure 52–2 Hemophilia: pathologic abnormalities— intraosseous (A) and subperiosteal (B) hemorrhage These types of hemorrhage can lead to hemophilic pseudotumors, with destruction and deformity of bone Ankle The radiographic findings in the ankle are similar to those in other involved joints, including soft tissue swelling, osteoporosis, marginal and central osseous erosions, and joint space narrowing (Fig 52–4) Tibiotalar slanting may be observed, creating an angular joint surface, a finding observed in epiphyseal dysplasias, juvenile chronic arthritis, and perhaps sickle cell anemia Bony ankylosis of the subtalar joints has also been described in hemophilia Osteonecrosis of the talus may be observed always the case In some patients, articular involvement never progresses beyond the first or second stage; in other patients, despite appropriate medical or surgical therapy, severe arthropathy develops A B Figure 52–3 Hemophilia: knee joint abnormalities Frontal (A) and lateral (B) radiographs demonstrate characteristic findings of hemophilia The bones are mildly osteoporotic, and the epiphyses are enlarged Note the well-defined or “etched” erosions of subchondral bone (arrowheads), the radiodense joint effusion (arrow), and the widened intercondylar notch of the femur 706 Section XIII Diseases of the Hematopoietic System Figure 52–5 Hemophilia: elbow joint abnormalities Figure 52–4 Hemophilia: ankle joint abnormalities Exten- sive abnormalities in the ankle include osteoporosis and joint space narrowing Note the tibiotalar slant with an angular joint surface (arrows) Observe sclerosis, flattening, and deformity of the bones The radial head is widened Note the enlargement of the radial fossa (arrow) Elbow Radiodense effusion, osteoporosis, and cartilagi- nous and osseous destruction are evident in the elbow in hemophilia (Fig 52–5) The trochlear and radial notches of the ulna are frequently widened, and the radial head may be enlarged Other Joints Typical hemophilic abnormalities may be apparent in other joints, including the hip, glenohumeral joint, and small articulations of the hand and foot Additional Abnormalities Several other abnormalities may be associated with hemophilia Osteonecrosis Epiphyseal fragmentation and collapse may be apparent in hemophilia These findings appear to be related to intraosseous bleeding, with subsequent collapse of bone, or to intracapsular bleeding, with elevation of intra-articular pressure, vascular occlusion, and subsequent osteonecrosis These changes are particularly common in the femoral head and talus (Fig 52–6) Ectopic Ossification Ossification may appear in periar- ticular soft tissue (Fig 52–7) This complication is most frequently apparent in the lower half of the body, particularly in the pelvis, where ossification extending from the lateral aspect of the ilium or ischium to the proximal end of the femur may be observed Figure 52–6 Hemophilia: osteonecrosis of the hip Intra- articular bleeding can produce osteonecrosis of the femoral head Findings include considerable flattening of the femoral head, subchondral cysts, mild joint space narrowing, and acetabular deformity Chapter 52 Bleeding Disorders 707 Cortical atrophy due to abnormal pressure, subperiosteal bone formation, and soft tissue extension are evident (Fig 52–8) Tumors arising in the soft tissue enlarge slowly, develop a fibrous capsule, and distort the subjacent osseous tissue by pressure erosion Soft tissue hemophilic pseudotumors are most common in the thigh and the gluteal region Infrequently, the soft tissue masses calcify Initially, a subperiosteal hematoma in hemophilia produces periostitis that can simulate malignancy (Ewing’s sarcoma, skeletal metastases) or infection An intraosseous hematoma leading to osteolytic lesions of varying size simulates primary and secondary neoplasms, tumor-like lesions, and infection In many patients, accurate diagnosis relies on knowledge of the patient’s underlying disease Other Articular Manifestations In hemophilia, joint contractures may complicate intra-articular destruction or soft tissue hemorrhage, with impingement on vessels and nerves Scintigraphy Increased sensitivity of the isotopic examination compared with clinical and radiographic evaluation is not unexpected, particularly at sites of acute arthropathy The radionuclide examination lacks specificity, however, and it is less effective in evaluating joints with chronic arthropathy Computed Tomography Figure 52–7 Hemophilia: ectopic ossification A large band of ossification extends from the lateral aspect of the ilium to the proximal portion of the femur (Courtesy of M Dalinka, MD, Philadelphia, Pa.) Because hemophilic pseudotumors commonly arise in or extend to periosseous soft tissues, they are often well characterized by computed tomography Soft tissue ossification in hemophilia is also well shown with this technique (Fig 52–9) Magnetic Resonance Imaging Fractures In hemophilia, fractures may occur spontaneously or after minor trauma Fracture healing in hemophilic patients proceeds normally, although pseudotumors may develop at the site of fracture Hemophilic Pseudotumor Hemophilic pseudotumor is a relatively uncommon manifestation of the disease, probably occurring in less than 2% of cases The bones that are implicated most frequently, in descending order of frequency, are the femur, the components of the osseous pelvis, the tibia, and the small bones of the hands Pseudotumors may be intraosseous or subperiosteal, or they may occur within the soft tissues It is probable that pseudotumors arise from hemorrhage Medullary bone destruction may produce small or large central or eccentric radiolucent lesions that are fairly well demarcated Trabeculae can extend across the lesions, and the surrounding bone is frequently sclerotic Cortical violation and periosteal bone formation may reach considerable proportions A large soft tissue mass may be encountered Mild, moderate, or massive bleeding may occur in subperiosteal locations In the immature skeleton, the periosteum is lifted easily by the accumulation of blood Spin echo magnetic resonance (MR) imaging sequences typically reveal regions in the joint with low to intermediate signal intensity on T1- and T2-weighted images, with foci of increased signal intensity on T2-weighted images Persistent low signal intensity in both types of images is consistent with the presence of synovial fibrosis, hemosiderin deposition, or both (Fig 52–10) The foci of high signal intensity on T2-weighted images are consistent with areas of synovial inflammation or fluid Owing to the changing signal characteristics of resolving hemorrhage, it may be difficult to distinguish between viscous joint fluid and fresh blood with MR imaging in this disease The intravenous administration of paramagnetic contrast agents, such as those containing gadolinium, may be useful in distinguishing among synovial inflammation, hemorrhage, and joint effusion The MR imaging characteristics of hemosiderin deposition in this disease are similar to those seen in other disorders accompanied by recurrent episodes of intra-articular bleeding Such processes include pigmented villonodular synovitis, neoplasms such as synovial hemangiomas, neuropathic osteoarthropathy, and chronic renal disease Hemosiderin collections lead to low signal intensity on all spin echo 708 Section XIII Diseases of the Hematopoietic System A B Figure 52–8 Hemophilia: pseudotumors A, Radiograph of the forearm reveal a pseudotumor involving the distal portion of the radius Note new bone formation extending into the soft tissues, with destruction and deformity of the underlying bone B, Striking bone and soft tissue abnormalities may accompany bleeding in hemophilia The deformed femur has a “cystic” appearance, and in places, its contour has been obliterated completely The hip is also abnormal (A, Courtesy of A Brower, MD, Norfolk, Va.) B A Figure 52–9 Hemophilia: pseudotumors Routine radiography (A) and transaxial computed tomography (B) reveal both bone and soft tissue abnormalities The extent of the process is better delineated with computed tomography, which shows a lobulated mass of low attenuation, a partial rim of higher attenuation, and residual and distorted trabeculae (Courtesy of R Cone, MD, San Antonio, Tex.) Chapter 52 Bleeding Disorders A 709 B Figure 52–10 Hemophilia: MR imaging A, Sagittal T1-weighted (TR/TE, 500/16) spin echo MR image shows anterior extension of the joint (arrow) The intra-articular contents are of low signal intensity Irregularity of the subchondral bone of the tibia is evident (arrowhead) B, Sagittal T2-weighted (TR/TE, 2000/80) spin echo MR image shows persistent low signal intensity anteriorly, with peripheral regions of higher signal intensity (arrow) Abnormal signal intensity is also seen in the tibia (arrowhead) The articular findings indicate synovial fibrosis or hemosiderin deposition (low signal intensity) and inflammation (high signal intensity) sequences and, to a greater degree, on all gradient echo sequences (Fig 52–11) Subchondral cystic lesions, a prominent feature of hemophilic arthropathy, can be evaluated with MR imaging The signal characteristics of these cysts, however, are dependent on the precise imaging sequence used and the contents of the lesions Fluid, fibrotic material, hemorrhage, or hemosiderin, in various combinations, may be present in the subchondral cysts, leading to inhomogeneity in signal intensity in some cases Cysts with high signal intensity on both T1- and T2-weighted spin echo MR images are related to recent hemorrhage; those with low signal intensity on T1-weighted and high signal intensity on T2-weighted spin echo MR images contain nonhemorrhagic fluid; and those with low signal intensity in both types of MR images relate to the presence of fibrous tissue and hemosiderin (see Fig 52–11) The signal behavior of these pseudotumors is complex, reflecting the effects of remote and recurrent bleeding and clot organization A peripheral margin of low signal intensity on T1- and T2-weighted spin echo MR sequences is consistent with the presence of fibrous tissue or hemosiderin, or both, in the wall of the pseudotumor Less uniform, however, are the signal characteristics of the interior portions of the pseudotumor, which may reveal regions of either high or low signal intensity on one or both of these sequences Intramuscular pseudotumors (as well as those in other locations) may reveal mural nodules (Fig 52–12) Pathogenesis of Hemophilic Arthropathy Generally, it is assumed that arthropathy in hemophilia results from intra-articular and periarticular hemorrhage In the synovial membrane, hypertrophy and inflammation, subsynovial fibrosis, and hemosiderin deposition are known responses to experimental hemarthrosis and resemble the findings in other articular disorders, particularly pigmented villonodular synovitis Cartilaginous abnormalities occurring after hemarthrosis are less constant The role of intra-articular iron deposits in the pathogenesis of hemophilic arthropathy is not clear The osseous abnormalities in hemophilic joints may result from certain toxic and chemical effects on bone and elevation of intraarticular pressure (due to hemarthrosis) and intramarrow pressure (due to focal destruction of weight-bearing surfaces) Hyperemia may be responsible for epiphyseal overgrowth in hemophilia Osteoporosis may relate to increased blood flow in capsular and epiphyseal blood vessels, as well as to disuse and immobilization Differential Diagnosis Hemarthrosis is not confined to hemophilic arthropathy It is frequent after trauma, in other articular and nonarticular disorders such as scurvy or myeloproliferative disease, and after excessive administration of anticoagulant medication In these other conditions, permanent cartilaginous and osseous findings resembling those of hemophilia are not encountered Articular abnormalities of hemophilia most resemble the changes of juvenile chronic arthritis (Table 52–2) It is often impossible to distinguish between these two disorders on the basis of radiographic abnormalities in a single joint Rather, it is the distribution of articular abnormalities in hemophilia and juvenile-onset rheumatoid arthritis (and other forms of juvenile chronic arthritis) that permits an accurate radiographic diagnosis In A B Figure 52–11 Hemophilia: MR imaging—hemosiderin deposition A, Sagittal intermediate-weighted (TR/TE, 2100/20) spin echo MR image demonstrates synovial proliferation of low signal intensity extending into and distorting Hoffa’s fat pad (arrows) B, Sagittal T2-weighted three-dimensional (TR/TE, 30/10; flip angle, 40 degrees) gradient echo MR image demonstrates “blooming” of the hemosiderin within the synovium (arrows) and a posterior tibial cyst containing fluid or hemorrhage (curved arrow) A B Figure 52–12 Hemophilia: MR imaging—pseudotumors Sagittal T1-weighted (TR/TE, 600/20) (A) and T2-weighted (TR/TE, 1500/80) (B) spin echo MR images reveal a pseudotumor in the gastrocnemius muscle with an elliptic shape Multiple various-sized lobulated nodules are seen attached to the capsule (arrows), exhibiting heterogeneous signal intensity compatible with blood clots in various stages of organization (From Jaovisidha S, Ryu KN, Hodler J, et al: Hemophilic pseudotumor: Spectrum of MR findings Skeletal Radiol 26:468, 1997.) 710 711 Chapter 52 Bleeding Disorders TABLE 52–2 Hemophilia versus Juvenile-Onset Rheumatoid Arthritis (JRA) Hemophilia JRA Common articular sites Knee, wrist, elbow Soft tissue swelling Osteoporosis Joint space narrowing Bony ankylosis Epiphyseal overgrowth Growth inhibition Epiphyseal collapse or osteonecrosis Periostitis Pseudotumors Spondylitis + + ± – + – + Knee, ankle, wrist, hand + + ± + + + + ± + – + – + +, present; –, absent hemophilia, the knee, ankle, and elbow are altered most commonly; in juvenile-onset rheumatoid arthritis, the articulations of the hands and wrists, as well as the larger joints and the spine, may be affected In some joints, the findings of hemophilia may simulate those of pigmented villonodular synovitis or infection These latter disorders are characteristically monoarticular, whereas joint involvement in hemophilia is usually polyarticular Articular and skeletal alterations accompanying neuromuscular diseases such as cerebral palsy, muscular dystrophy, and poliomyelitis may also resemble those of hemophilia On rare occasions, intraarticular bleeding in association with certain hemorrhagic diatheses may lead to an arthropathy identical to that of hemophilia (Table 52–3) BLEEDING DIATHESES AND HEMANGIOMAS General Features Hemangiomas are vascular tumors, most often located in the skin, that appear in the early postnatal period Hemangiomas may be associated with unusual syndromes, some of which produce hematologic abnormalities The association of varicose veins, soft tissue and bony hypertrophy, and cutaneous hemangiomas is known as Klippel-Trénaunay syndrome An underlying vascular abnormality consisting of atresia and hypoplasia or obstruction of the deep venous system is noted When these findings are associated with an arteriovenous fistula, the condition is commonly called Parke-Weber syndrome Additional variations of Klippel-Trénaunay syndrome include cutaneous lymphangiomas and facial hemihypertrophy Klippel-Trénaunay syndrome affects both sexes The nevus is usually present at birth, and varices appear, sometimes at birth but typically in the first few years of life Osseous and soft tissue hypertrophy is also evident in early life but becomes more obvious during the adolescent growth spurt Usually only one lower limb is involved The natural history of Klippel-Trénaunay syndrome is variable, although worsening of venous insufficiency is the rule TABLE 52–3 Heritable Disorders of Blood Coagulation Disorder Hereditary Hemorrhagic Tendency Hemarthrosis Classic hemophilia (factor VIII deficiency) Christmas disease (factor IX deficiency) von Willebrand’s disease (factor VIII deficiency, platelet abnormalities) Plasma thromboplastin antecedent (PTA, factor IX) deficiency Hageman trait (deficiency of Hageman factor, factor XII) Fletcher trait (deficiency of plasma prekallikrein) Fitzgerald trait (deficiency of high-molecular-weight kininogen) Parahemophilia (factor V deficiency) Stuart factor deficiency (factor X deficiency) Factor VII deficiency Hereditary hypoprothrombinemia (prothrombin deficiency) Congenital deficiency of fibrinogen Congenital dysfibrinogenemia (structural abnormality of fibrinogen) Congenital deficiency of fibrin-stabilizing factor (factor XIII deficiency) X-linked X-linked Mild to severe Mild to severe Common Common Autosomal dominant Autosomal recessive Mild to severe Mild Uncommon Rare Autosomal recessive Autosomal recessive Autosomal recessive None to mild None None Usually absent Absent Absent Autosomal recessive Autosomal recessive Autosomal recessive Autosomal recessive Autosomal recessive Autosomal dominant Moderate Severe Mild to moderate Mild to severe Severe None to mild Rare Variable Variable Variable Variable Variable Unknown Severe Rare 712 Section XIII Diseases of the Hematopoietic System Kasabach-Merritt syndrome consists of papillary hemangiomas and extensive purpura Hematologic abnormalities associated with Kasabach-Merritt syndrome include thrombocytopenia; deficiencies of factors V, VII, VIII, and IX; prothrombin depression; hypofibrinogenemia; and microangiopathic hemolytic anemia A consumption coagulopathy caused by intravascular coagulation within the hemangioma makes these patients (usually infants) susceptible to hemorrhage Articular Abnormalities Arthropathies are not commonly reported in either Klippel-Trénaunay syndrome or Kasabach-Merritt syndrome, although, in the latter condition, patients may Figure 52–13 Arthropathy in association with hemangiomas and bleeding diatheses This 11-year-old had recurrent bilateral knee pain and abdominal discomfort At the age of weeks, multiple hemangiomas of the lower extremities and abdomen were noted Extensive clinical and laboratory evaluation confirmed the diagnosis of multiple giant hemangiomas and varicosities (Klippel-Trénaunay syndrome), Kasabach-Merritt syndrome, and a consumption coagulopathy On this radiograph of the knee, a soft tissue phlebolith (arrow) is apparent The distal femoral and proximal tibial epiphyses are enlarged, with irregularities of the subchondral bone and a widened intercondylar notch (open arrows) (From Resnick D, Oliphant M: Hemophilia-like arthropathy of the knee associated with cutaneous and synovial hemangiomas: Report of cases and review of the literature Radiology 114:323, 1975.) suffer joint stiffness and “degenerative” changes Rarely, an arthropathy of the knee resembling hemophilia may be evident (Fig 52–13) FURTHER READING Arnold WD, Hilgartner MW: Hemophilic arthropathy: Current concepts of pathogenesis and management J Bone Joint Surg Am 59:287, 1977 Brant EE, Jordan HH: Radiologic aspects of hemophilic pseudotumors in bone AJR Am J Roentgenol 115:525, 1972 deValderrama JAF, Matthews JM: The haemophilic pseudotumor or haemophilic subperiosteal haematoma J Bone Joint Surg Br 47:256, 1965 Gaary E, Gorlin JB, Jaramillo D: Pseudotumor and arthropathy in the knees of a hemophiliac Skeletal Radiol 25:85, 1996 Greene WB, Yankaskas BC, Guilford WB: Roentgenographic classifications of hemophilic arthropathy J Bone Joint Surg Am 71:237, 1989 Hermann G, Gilbert MS, Abdelwahab IF: Hemophilia: Evaluation of musculoskeletal involvement with CT, sonography, and MR imaging AJR Am J Roentgenol 158:119, 1992 Johnson JB, Davis TW, Bullock WH: Bone and joint changes in hemophilia Radiology 63:64, 1954 Jordan HH: Hemophilic Arthropathies Springfield, Ill, Charles C Thomas, 1958 Kasabach HH, Merritt KK: Capillary hemangioma with extensive purpura: Report of a case Am J Dis Child 59:1063, 1940 Kontras SB: The Klippel-Trenaunay-Weber syndrome Birth Defects 10:177, 1974 Pettersson H, Ahlberg S, Nilsson IM: A radiologic classification of hemophilic arthropathy Clin Orthop 149:153, 1980 Pettersson H, Gilbert MS: Diagnostic Imaging in Hemophilia Berlin, Springer-Verlag, 1985 Phillips GN, Gordon DH, Martin EC, et al: The KlippelTrenaunay syndrome: Clinical and radiological aspects Radiology 128:429, 1978 Plazanet FR, du Boullay CH, De Faux F, et al: Open synovectomy for the prevention of recurrent hemarthrosis of the ankle in patients with hemophilia: A report of five cases with magnetic resonance imaging documentation Rev Rhum Engl Ed 64:166, 1997 Resnick D, Oliphant M: Hemophilia-like arthropathy of the knee associated with cutaneous and synovial hemangiomas: Report of cases and review of the literature Radiology 114:323, 1975 Richardson ML, Helms CA, Vogler JB III, et al: Skeletal changes in neuromuscular disorders mimicking juvenile rheumatoid arthritis and hemophilia AJR Am J Roentgenol 143:893, 1984 Roebuck DJ: Klippel-Trenaunay and Parke-Weber syndromes AJR Am J Roentgenol 169:311, 1997 Roosendaal G, Vianen ME, Wenting MJG, et al: Iron deposits and catabolic properties of synovial tissue from patients with haemophilia J Bone Joint Surg Br 80:540, 1998 Vaz W, Cockshott WP, Martin RF, et al: Myositis ossificans in hemophilia Skeletal Radiol 7:27, 1981 Weber FP: Hemangiectatic hypertrophy of limbs—congenital phlebacteriectasis and so-called congenital varicose veins Br J Child Dis 15:13, 1918 Wilson DA, Prince JR: MR imaging of hemophilic pseudotumors AJR Am J Roentgenol 150:349, 1988 ... Mall W 300E Philadelphia, Pennsylvania 19 106 BONE AND JOINT IMAGING Copyright © 2005, 19 96, 19 89 by Elsevier Inc ISBN 0-7 216 -0270-3 All rights reserved No part of this publication may be reproduced... references and index ISBN 0-7 216 -0270-3 Bones Imaging Joints Imaging Bones—Diseases—Diagnosis Joints—Diseases—Diagnosis I Kransdorf, Mark J II Title [DNLM: Bone Diseases—diagnosis Diagnostic Imaging methods... edition of Bone and Joint Imaging and a few years after the publication of the fourth edition of the larger Diagnosis of Bone and Joint Disorders, the third edition of Bone and Joint Imaging is now