Background: As world population gets older, more cases of collapse fracture, disc herniation,
vertebral osteomyelitis and chord compression and surgeries on spine are noted. One of the
complications is pain and in differential diagnosis are infectious and non-infectious processes. The
method of choice for the diagnosis of infection in spinal column is MRI, however it is inapplicable
in many cases. In addition, other imaging modalities like CT scan, PET or bone scintigraphy have
their own limitations. UBI is a polypeptide which is taken by bacteria in the cell wall and therefore
Tc99m-UBI has been used to detect infectious processes with promising results.
Objective: The aim of this study was to use Tc 99m-UBI to differentiate infectious process from
other etiologies in patients with pain in spinal column in which other diagnostic methods were not
Methods: We investigated 30 patients (20 females and 10 males) with back-pain. 11 had a history of
surgical manipulation on spine. All patients first were scanned and then were treated and followed
by a neurosurgeon and an infectious disease specialist. Both treating physicians were blind to the
result of the scan and final data (after 2 years follow up) were analyzed by a third physician.
Results: The result showed qualitative assessment and quantitative interpretation of UBI scan (using
target to background threshold of 1.29) have 33% sensitivity and 95% specificity and 33% and 80%
specificity respectively in the diagnosis of osteomyelitis of spinal column.
Conclusion: These results suggest that UBI scan is not recommended in initial assessment but may
be helpful for the diagnosis of patient with non-infectious processes; however more studies are
needed for precise conclusion.