Object The ideal surgical management of high-grade spondylolisthesis remains unclear. Concerns regarding the original Bohlman transsacral interbody fusion technique with stand-alone autologous fibular strut include late graft fracture and incomplete reduction of lumbosacral kyphosis. The authors' goal was to evaluate the radiographic and surgical outcomes of patients treated for high-grade spondylolisthesis with either transsacral S-1 screws or standard pedicle screw fixation augmenting the Bohlman posterior transsacral interbody fusion technique. Methods A retrospective review of patients who underwent fusion for high-grade spondylolisthesis in which a Bohlman oblique posterior interbody fusion augmented with either transsacral or standard pedicle screw fixation was performed by 4 spine surgeons was completed. Estimated blood loss, operating time, perioperative complications, and need for revision surgery were evaluated. Upright pre- and postsurgical lumbar spine radiographs were compared for slip percent and slip angle. Results Sixteen patients (12 female and 4 male) with an average age of 29 years (range 9–66 years) were evaluated. The average clinical follow-up was 78 months (range 5–137 months) and the average radiographic follow-up was 48 months (range 5–108 months). Ten L4–S1 and 6 L5–S1 fusions were performed. Five fibular struts and 11 titanium mesh cages were used for interbody fusion. Six patients had isolated transsacral screws placed, with 2 (33%) of the 6 requiring revision surgery for nonunion. No nonunions were observed in patients undergoing spanning pedicle screw fixation augmenting the interbody graft. Six patients experienced perioperative complications including 3 iliac crest site infections, 1 L-5 radiculopathy without motor involvement, 1 deep vein thrombosis, and 1 epidural hematoma requiring irrigation and debridement. The average estimated blood loss and operating times were 763 ml and 360 minutes, respectively. Slip percent improved from an average of 62% to 37% (n = 16; p < 0.01) and slip angle improved from an average of 18° to 8° (n = 16; p < 0.01). No patient experienced L-5 or other motor deficit postoperatively. Conclusions The modified Bohlman technique for treatment of high-grade spondylolisthesis has reproducible outcomes among multiple surgeons and results in significant improvements in slip percent and slip angle. Fusion rates were high (14 of 16; 88%), especially with spanning instrumentation augmenting the oblique interbody fusion. Rates of L-5 motor deficit were low in comparison with techniques involving reduction of the anterolisthesis.

Study Design. A cross-sectional study. Objective. This study investigates the prevalence of incidental vertebral marrow signal abnormality (VMSA) in thoracolumbar spine magnetic resonance imaging (MRI) ordered for the evaluation of back and/or leg pain and assess the clinical work-up for VMSAs. Summary of Background Data. Patients presenting with back pain are often referred for spine MRI for diagnostic evaluation. VMSA is most frequently found in the lumbar spine and is of clinical concern because it can represent malignancy. Standardized procedures for reporting and managing VMSAs do not exist. Methods. The radiology database at the Oregon Health & Science University health system was queried to identify patients with thoracolumbar spine MRI scans performed between January 2014 and June 2016. Patients 16 years or older with MRIs ordered by providers at a multidisciplinary spine specialty clinic for the diagnostic evaluation of back and/or leg pain were included. Radiology reports were searched for keywords pertaining to VMSAs, such as “malignancy.” Medical records of these patients were further reviewed for the clinical work-up and final diagnoses pertaining to the VMSA. Results. The study sample included 1503 individual patients, of whom 65 (4%) had MRI radiology reports that described a VMSA. Thirty-one (48%) of the 65 patients with VMSAs had further evaluation recommended by radiology. Ten (32%) of these 31 patients were followed clinically without further diagnostic testing for the VMSA. Of the 65 patients with VMSAs, only one was diagnosed with malignancy (multiple myeloma). Conclusion. While VMSAs are not frequently found on thoracolumbar MRIs ordered to evaluate back and/or leg pain, there is a large amount of heterogeneity in how these abnormalities are documented and managed. This may indicate the need for clinical guidelines for the reporting and management of VMSAs detected on spine MRI and for improvement in communication between radiologists and ordering providers. Level of Evidence: 3