Smarter Decisions,
Better Care
UpToDate synthesizes the most recent medical information into evidence-based practical recommendations clinicians trust to make the right point of care decisions.
For more information, click below.
Subscribers log in here
Related articles
Related Searches
| AuthorPerry Horwich, MD | Section EditorsDaniel J Sexton, MDMary Hochman, MD | Deputy EditorElinor L Baron, MD, DTMH |
Topic Outline
INTRODUCTION
Imaging can be a useful tool in the setting of suspected osteomyelitis, particularly for supporting a presumed clinical diagnosis, delineating the extent of disease, and planning therapy (table 1).
However, interpretation of imaging findings can be a diagnostic challenge [1]. The sensitivity of radiographs for detecting of acute osteomyelitis is limited. MRI and nuclear medicine studies can have limited specificity in the setting of confounding bony pathology, although both have high negative predictive value for osteomyelitis.
The benefits and limitations of radiographs, magnetic resonance imaging (MRI), computed tomography (CT), nuclear modalities, and ultrasonography for the diagnosis of osteomyelitis will be reviewed here. An integrated diagnostic approach including radiography together with other clinical data for the diagnosis of osteomyelitis is discussed in detail separately. (See "Overview of osteomyelitis in adults", section on 'Suggested diagnostic approach'.)
PATHOPHYSIOLOGY
In the setting of osteomyelitis, inflammatory exudate in the marrow leads to increased intramedullary pressure, with subsequent extension of exudate into the bone cortex where it can rupture through to the periosteum. If this occurs, the periosteal blood supply to the bone is interrupted, leading to necrosis. The resulting fragments of isolated dead bone (known as sequestra) can be visualized radiographically.
Acute osteomyelitis refers to infection in the bone prior to development of sequestra. In some forms of infection, development of sequestra is relatively slow (such as vertebral osteomyelitis), while in others the development of sequestra occurs relatively rapidly (such as osteomyelitis in the setting of prosthetic devices or compound fractures) [1]. Following formation of sequestra, the infection is considered chronic osteomyelitis. Other hallmarks of chronic osteomyelitis include involucrum (reactive bony encasement of the sequestrum), local bone loss, and sinus tracts (extension of infection through cortical bone).
Subscribers log in here