Jan-Sven Jarvers

Use of Simultaneous 18F-FDG PET/MRI for the Detection of Spondylodiskitis

The diagnosis of spondylodiskitis is often challenging. MRI is quite sensitive but lacks specificity, and distinction from erosive osteochondritis is often difficult. We sought to assess the diagnostic value of 18F-FDG PET combined with MRI (combined 18F-FDG PET/MRI) in patients with suspected spondylodiskitis and an inconclusive clinical or MRI presentation. Methods: In a prospective study, 30 patients with previous inconclusive MRI results and suspected spondylodiskitis underwent combined 18F-FDG PET/MRI, including precontrast and postcontrast standard spine MRI sequences. The image datasets were evaluated on dedicated workstations by 2 radiology residents and 1 board-certified nuclear medicine physician independently and then in consensus. Because of severe susceptibility artifacts, only 28 of 30 image datasets were evaluable, with a total of 29 regions of suspected spondylodiskitis. SUV ratios (affected disk/reference disk) were determined. The imaging results were compared with histopathology or clinical follow-up as a reference standard and subjected to statistical analysis. Results: The reference standards identified spondylodiskitis in 12 disks and excluded spondylodiskitis in 17 disks. For MRI alone, the sensitivity was 50%, the specificity was 71%, the positive predictive value was 54%, and the negative predictive value was 67%. Adding the PET data resulted in sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 88%, 86%, and 100%, respectively. In a receiver operating characteristic curve analysis, an SUVmax ratio threshold of 2.1 resulted in 92% sensitivity and 88% specificity (area under the receiver operating characteristic curve, 0.95). Neither the level of C-reactive protein nor the leukocyte count at the time of PET/MRI was related to the reference standard diagnosis of spondylodiskitis. Conclusion: In patients with inconclusive clinical or MRI findings, the use of 18F-FDG PET/MRI significantly increased diagnostic certainty for the detection of spondylodiskitis.

Pyogenic Spondylodiscitis of the Thoracic Spine: Outcome of 1-Stage Posterior Versus 2-Stage Posterior and Anterior Spinal Reconstruction in Adults

OBJECTIVE The aim of this study was to compare the clinical, radiologic, and functional outcomes of a 1-stage posterior treatment versus a 2-stage posterior-anterior treatment in patients with pyogenic thoracic spondylodiscitis. METHODS A 1-stage posterior debridement, stabilization, and fusion with titanium-coated polyetheretherketone (PEEK) or mesh cage through a dorsolateral approach was performed in group A. A 2-stage procedure with initial posterior stabilization and debridement and second-stage fusion with a PEEK cage or mesh cage was performed with an anterior approach in group B. Clinical outcomes included Oswestry Low Back Pain Disability Questionnaire and visual analog scale score. Radiologic outcomes included fusion rate and kyphotic angle correction. Secondary variables included pathogens, complications, blood loss, and operative time. RESULTS One-level spondylodiscitis was treated surgically in the thoracic spine of 47 patients: 25 patients in group A and 22 patients in group B. The most frequent segment was T12-L1 (27%). There was a significantly longer operative time and greater blood loss (P > 0.001) in group B. At last follow-up, sagittal profile reconstruction was significantly better (P > 0.05) in group B. Both groups showed similar radiologic results with fusion in 92% of cases. Improved clinical outcomes, pain, and quality of life were achieved in both groups with no significant differences between the 2 groups. CONCLUSIONS Better reconstruction of the sagittal profile was achieved in the posterior-anterior-treated group, but this did not affect the clinical outcome. No significant differences were found in the clinical and functional outcomes between the 2 groups. Posterior-anterior combined treatment should be considered in cases of large anterior defects if a posterior reconstruction is inadequate.

Treatment of Injuries to the Subaxial Cervical Spine: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU)

Study Design: Expert consensus. Objectives: To establish treatment recommendations for subaxial cervical spine injuries based on current literature and the knowledge of the Spine Section of the German Society for Orthopaedics and Trauma. Methods: This recommendation summarizes the knowledge of the Spine Section of the German Society for Orthopaedics and Trauma. Results: Therapeutic goals are a stable, painless cervical spine and protection against secondary neurologic damage while retaining maximum possible motion and spinal profile. The AOSpine classification for subaxial cervical injuries is recommended. The Canadian C-Spine Rule is recommended to decide on the need for imaging. Computed tomography is the favoured modality. Conventional x-ray is preserved for cases lacking a “dangerous mechanism of injury.” Magnetic resonance imaging is recommended in case of unexplained neurologic deficit, prior to closed reduction and to exclude disco-ligamentous injuries. Computed tomography angiography is recommended in high-grade facet joint injuries or in the presence of vertebra-basilar symptoms. A0-, A1- and A2-injuries are treated conservatively, but have to be monitored for progressive kyphosis. A3 injuries are operated in the majority of cases. A4- and B- and C-type injuries are treated surgically. Most injuries can be treated with anterior plate stabilization and interbody support; A4 fractures need vertebral body replacement. In certain cases, additive or pure posterior instrumentation is needed. Usually, lateral mass screws suffice. A navigation system is advised for pedicle screws from C3 to C6. Conclusions: These recommendations provide a framework for the treatment of subaxial cervical spine Injuries. They give advice about diagnostic measures and the therapeutic strategy.

Cervical Spine Injuries

The cervical spine is the most flexible part of the spine and protects the upper part of the spinal cord in the transition zone to the static thoracic spine. Furthermore, it has a complex bond to the cranium. The cervical spine realizes a balanced bearing of the relatively big head on the body. In cases of unphysiological application of force and high-velocity trauma, the heavy head acts as a catapult and can lead to both simple and complicated injuries of the ligamentous and bony structures.