Elevated serum S100B levels in acute spinal fracture without head injury

Background S100B is a biomarker that reflects injury to the central nervous system. As the spine is an integral part of the spinal cord, a study was undertaken to investigate whether serum S100B levels are associated with acute spinal fracture without head injury. Methods The study population consisted of 32 consecutive patients aged >= 18 years in whom the emergency physicians suspected spinal fractures. All the patients underwent CT scans to establish the diagnosis of spinal fracture. MRI was then performed on all the patients to determine the presence of spinal cord injury. Results Serum S100B levels were higher in the spinal fracture group than in the non-spinal fracture group, and 19 of the 20 patients in the spinal fracture group (95%) had an S100B level >0.12 mu g/l, whereas all 12 of the non-spinal fracture group had an S100B level <= 0.12 mu g/l. The S100B level in patients with epidural encroachment of the spinal cord was significantly higher (0.22-4.58 mu g/l; mean 2.45 mu g/l; 95% CI 0.95 to 3.94) than in those without epidural encroachment (0.114-2.87 mu g/l; mean 0.80 mu g/l; 95% CI 0.24 to 1.37) (p=0.037). Plain radiography revealed no definite abnormal findings in half of the patients with spinal fracture. Conclusions Serum S100B levels are raised in all patients with acute spinal fracture without head injury. Spinal fracture may therefore be one of the extracerebral sources of S100B. Serum S100B levels may be an effective tool for excluding subtle spinal fractures with no clear radiographic findings.