What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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Findings •
Radiographs demonstrate anterior and posterior fusion extending from L3-L5 with questionable lucency of the endplates at L2-L3. CT study then shows bone resorption about the L3 pedicle screws and areas of loss of endplate cortical margin at L2-L3. MRI shows markedly abnormal signal centered at L2-L3 which is low on T1 and then high on T2( IR) both involving the disc and bone. Marked high signal is also seen of the psoas musculature and there is central canal stenosis. Following gadolinium, there is enhancement of the bone and soft tissue without a focal fluid collection.
What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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Diagnosis: Infectious Discitis/Osteomyelitis •
Following surgery many complications are possible including infection, fracture, and when orthopedic hardware is placed- mechanical loosening. Often, multiple imaging modalities and even biopsy are necessitated to emerge at a diagnosis. In this case, on the CT exam, there is lucency around the hardware with portions of the endplates showing a loss of cortical margins. It is difficult to know from that study alone whether or not the findings are from mechanical loosening and aseptic bone resorption or infection.
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The clinical history in this case is also nonspecific and so further investigation with MRI was pursued. The degree of abnormal signal of the disc and bone together with the inflammatory changes in the soft tissue are in keeping with infection. A fracture may have similar findings but no fracture line was seen and the degree of enhancement would be atypical. Degenerative changes likewise may present similarly but the extent of the findings and degree of enhancement would again be atypical.
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Infection in this situation is typically from hematogenous spread that may be from a genitourinary, dental, respiratory, or other origin. In the adult, the spread is first to the endplates with then subsequent spread into the disc and then extending into the adjacent end plate. As in this case, patients are treated with antibiotics and in this case additional decompression and fusion was performed. The decompression was secondary to the central canal stenosis and the fusion because of the degree of bone resorption yielding an unstable fusion construct.
What’s the Diagnosis – Case 64
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What’s the Diagnosis – Case 64
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