Imaging features of musculoskeletal tuberculosis

The purpose of this article is to review the imaging characteristics of musculoskeletal tuberculosis. Skeletal tuberculosis represents one-third of all cases of tuberculosis occurring in extrapulmonary sites. Hematogenous spread from a distant focus elsewhere in the body is the cornerstone in the understanding of imaging features of musculoskeletal tuberculosis. The most common presentations are tuberculous spondylitis, arthritis, osteomyelitis, and soft tissue involvement. The diagnostic value of the different imaging techniques, which include conventional radiography, CT, and MR imaging, are emphasized. Whereas conventional radiography is the mainstay in the diagnosis of tuberculous arthritis and osteomyelitis, MR imaging may detect associated bone marrow and soft tissue abnormalities. MR imaging is generally accepted as the imaging modality of choice for diagnosis, demonstration of the extent of the disease of tuberculous spondylitis, and soft tissue tuberculosis. Moreover, it may be very helpful in the differential diagnosis with pyogenic spondylodiscitis, as it may easily demonstrate anterior corner destruction, the relative preservation of the intervertebral disk, multilevel involvement with or without skip lesions, and a large soft tissue abscess, as these are all arguments in favor of a tuberculous spondylitis. On the other hand, CT is still superior in the demonstration of calcifications, which are found in chronic tuberculous abscesses.     

Imaging features of bilateral breast abnormalities

There are various-causes, broad-spectrum, heterogeneous groups with various biologic profiles, and imaging features of bilateral breast abnormalities. As imaging modalities continue to be developed, the ability to detect subtle or tiny abnormalities is improved in the contralateral breast of patients already diagnosed with unilateral breast disease, especially in breast cancer patients when using magnetic resonance imaging. Furthermore, some diseases involved bilateral breast, simultaneously. The purpose of this review is to describe imaging features of the bilateral breast abnormalities—common diseases and simultaneously involving diseases. In order to provide adequate treatment and to prevent misdiagnosis, a complete understanding of the imaging and clinical features of bilateral breast abnormalities of common diseases as well as those of simultaneously involving diseases is necessary.     

Imaging features of musculoskeletal involvement in systemic sclerosis

This article describes the radiographic, sonographic and magnetic resonance (MR) features of musculoskeletal involvement in patients with systemic sclerosis (SSc). Conventional radiography is the traditional method of detecting digital calcifications, but ultrasonography (US) is also able to detect such calcifications before they appear on radiographs. MR imaging can be used to diagnose overlapping conditions (i.e., SSc and myositis or SSc and rheumatoid arthritis), and less frequently, to reveal neurologic complications of SSc. In patients with vascular ulcers, MR angiography is able to depict decreased flow within collateral digital arteries.     

Imaging of musculoskeletal infections

Imaging studies play a critical role in the diagnosis and management of musculoskeletal infections in children. Conventional radiography is usually the first imaging study performed with other imaging modalities as needed. Ultrasound is helpful in detecting joint effusions and fluid collections in the soft tissue and subperiosteal regions, and may guide localization for aspiration or drainage. CT can demonstrate osseous and soft tissue abnormalities and is ideal for detecting gas in soft tissues. Nuclear scintigraphy and MR imaging are valuable because of their high sensitivity. Scintigraphy is particularly useful in identifying multifocal involvement, which is an important consideration in neonatal osteomyelitis and CRMO. MR imaging provides accurate information on both the soft tissues and bones and is our imaging study of choice for evaluating the local extent of musculoskeletal infections.     

Imaging of musculoskeletal trauma

Many significant papers in the current literature on musculoskeletal trauma deal with new advances in MR imaging. The increasing role of MR imaging in the evaluation of traumatic lesions of the knee explains the number of papers dealing with the differentiation of true traumatic lesions from normal variants or clinically insignificant changes. Other contributions on musculoskeletal trauma deal with more conventional imaging techniques, such as arthrography, plain films, and even complex tomography.     

Imaging of musculoskeletal fibromatosis.

The musculoskeletal fibromatoses comprise a wide range of lesions with a common histopathologic appearance. They can be divided into two major groups: superficial and deep. The superficial fibromatoses are typically small, slow-growing lesions and include palmar fibromatosis, plantar fibromatosis, juvenile aponeurotic fibroma, and infantile digital fibroma. The deep fibromatoses are commonly large, may grow rapidly, and are more aggressive. They include infantile myofibromatosis, fibromatosis colli, extraabdominal desmoid tumor, and aggressive infantile fibromatosis. Radiographs typically reveal a nonspecific soft-tissue mass, and calcification is common only in juvenile aponeurotic fibroma. Advanced imaging (ultrasonography, computed tomography, and magnetic resonance [MR] imaging) demonstrates lesion extent. Involvement of adjacent structures is common, reflecting the infiltrative growth pattern often seen in these lesions. MR imaging may show characteristic features of prominent low to intermediate signal intensity and bands of low signal intensity representing highly collagenized tissue. However, fibromatoses with less collagen and more cellularity may have nonspecific high signal intensity on T2-weighted images. Local recurrence is frequent after surgical resection due to the aggressive lesion growth. It is important for radiologists to recognize the imaging characteristics of musculoskeletal fibromatoses to help guide the often difficult and protracted therapy and management of these lesions.     

Imaging of musculoskeletal complications of hemophilia

In patients with hemophilia, hemarthrosis often occurs in one or several joints and may progress to a destructive, disabling arthropathy. Treatment includes continuous or on-demand clotting factor replacement and radionuclide or open synovectomy. The radiographic findings of hemophilic arthropathy depend on the stage of disease, the age of the patient at onset, and the joint involved. These findings include joint effusion, soft tissue swelling, epiphyseal overgrowth, subchondral cysts, osseous erosion, and secondary degenerative changes. Magnetic resonance imaging (MRI) is the most accurate imaging modality for assessing hemophilic arthropathy and may have a significant impact on patient management. MRI is anticipated to be useful in documenting early joint changes when treatment may be most effective. Hemophilic pseudotumor is a chronic, encapsulated, hemorrhagic fluid collection that usually destroys bone and may become quite large. Both computed tomography and MRI are useful in determining the extent of this lesion.     

Imaging of musculoskeletal disorders in children

A review of the year's literature on musculoskeletal disorders in infants and children includes many advances in imaging principles, especially MR imaging pulse sequences. We have not attempted to review these advances because the principles are essentially the same in children as in adults. We have confined this review to several topics including the importance of differentiating the findings in osteogenesis imperfecta from those in the abused child, limb-lengthening procedures in infants and children, the treatment of slipped upper femoral capital epiphysis, spinal anomalies, and skeletal abnormalities associated with cloacal exstrophy. A brief comment on cervical spine films in pediatric trauma patients is also included.     

Imaging of musculoskeletal and spinal tuberculosis

The diagnosis of tuberculosis of the musculoskeletal system is difficult for many reasons. As Walker states, to diagnose tuberculosis one must consider the possibility. The uncommonness of osteoarticular MTb results in clinician inexperience, which leads to overlooking the diagnosis. Subtle early manifestations may elude detection. Negative skin tests and normal chest films do not exclude the consideration of tuberculosis. The most conclusive means of reaching the diagnosis (biopsy and culture) necessitate invasive procedures that are not always definitive, and may require repeated attempts. Management and surgical decisions, however, rely on prompt diagnosis; diagnostic delay has prognostic implications and results in significant morbidity. Musculoskeletal tuberculosis produces no pathognomonic imaging signs, and in advanced stages mimics other disease processes. Despite these difficulties, the diagnostician's goal is to catch the disease as early as possible, because antibiotic treatment can lead to resolution and obviate more radical management. The radiologist must be aware of the groups at greatest risk, and typical and atypical presentations at imaging. The eventual eradication of MTb is conceivable, although not presently within our grasp. Maintaining reasonable suspicion and developing cognizance of the patterns of presentation allow the radiologist to diagnose efficiently the patient who presents with osteoarticular tuberculosis.     

Imaging of lymphoma of the musculoskeletal system

Imaging plays a crucial role in staging and the assessment of treatment response in patients who have lymphoma of the musculoskeletal system. This article reviews imaging features of lymphoma of bone, muscles, cutaneous, and subcutaneous tissue. At radiography, lymphoma of the bone is most commonly lytic, but the affected bone also can appear deceptively normal, even when a large tumor is present. At CT, lymphoma of muscle can be homogenous in attenuation, and it may not show contrast enhancement, making tumor detection more difficult. Post-treatment changes often are encountered at MR imaging and positron emission tomography, and when considered in light of the patient's therapy regimen (eg, radiation therapy and granulocyte-colony stimulating factor), they usually can be differentiated from tumor. Post-treatment changes include diffuse FDG uptake in marrow after chemotherapy, indicating rebound of normal marrow, and MR imaging signal abnormalities that may persist for anywhere from a few months to years after treatment.     

骨肌系统淀粉样变性的MRI表现

淀粉样变性（AM）是由多种疾病引起的一组临床症候群,多见于肾衰而行透析治疗的病人或浆细胞骨髓瘤病人。该病是由于淀粉样物质沉积于器官或组织的细胞外间隙所引起。AM累及骨肌系统较为少见,病变的MRI表现不典型,容易误诊。就AM的概念、分类及其在骨关节及肌肉的MRI特点及鉴别诊断予以综述。     

Imaging findings of sternal abnormalities

Radiographic findings in the sternal abnormalities are often nonspecific, showing appearances from a localized benign lesion to an aggressive lesion as seen with infections and malignant neoplasms. A specific diagnosis of sternal abnormalities can be suggested on the basis of CT and MR characteristics. Familiarity with the presentation and variable appearance of sternal abnormalities may aid the radiologist is suggesting a specific diagnosis. We present among others characteristic radiographic findings of hemangioma, chondrosarcoma, hydatid disease, and SAPHO syndrome. In those cases in which findings are not specific, cross-sectional imaging modalities may help the clinician in their management. Received 3 May 1996; Revision received 10 July 1996; Accepted 1 August 1996