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Henry Ahn and Michael G. Fehlings


In this report, the authors suggest evidence-based approaches to minimize the chance of perioperative spinal cord injury (POSCI) and optimize outcome in the event of a POSCI.


A systematic review of the basic science and clinical literature is presented.


Authors of clinical studies have assessed intraoperative monitoring to minimize the chance of POSCI. Furthermore, preoperative factors and intraoperative issues that place patients at increased risk of POSCI have been identified, including developmental stenosis, ankylosing spondylitis, preexisting myelopathy, and severe deformity with spinal cord compromise. However, no studies have assessed methods to optimize outcomes specifically after POSCIs. There are a number of studies focussed on the pathophysiology of SCI and the minimization of secondary damage. These basic science and clinical studies are reviewed, and treatment options outlined in this article.


There are a number of treatment options, including maintenance of mean arterial blood pressure > 80 mm Hg, starting methylprednisolone treatment preoperatively, and multimodality monitoring to help prevent POSCI occurrence, minimize secondary damage, and potentially improve the clinical outcome of after a POSCI. Further prospective cohort studies are needed to delineate incidence rate, current practice patterns for preventing injury and minimizing the clinical consequences of POSCI, factors that may increase the risk of POSCI, and determinants of clinical outcome in the event of a POSCI.

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Yusuke Nishimura, Nova B. Thani, Satoru Tochigi, Henry Ahn and Howard J. Ginsberg


Symptomatic thoracic disc herniations (TDHs) are relatively uncommon, and the technical challenges of resecting the offending disc are formidable due to the location of spinal cord that has relatively poor perfusion characteristics within a narrow canal. The majority of disc herniations are long-standing calcified discs that can be adherent to the ventral dura. Real-time intraoperative ultrasound (RIOUS) visualization of the spinal cord during the retraction and resection of the disc greatly enhances the safety and efficacy of disc resection. The authors have adopted the posterior laminectomy with pedicle-sparing transfacet approach with real-time ultrasound guidance in their practice, and they present the clinical outcome in their patients to illustrate the safety profile of this technique.


Sixteen consecutive patients undergoing operative management of TDHs were identified from the authors' database. All patients underwent microdiscectomy through a posterior transfacet pedicle-sparing approach under RIOUS. Outcomes and complications were retrospectively assessed in this patient series. Clinical records and pre- and postoperative imaging studies were scrutinized to assess levels and types of disc herniation, blood loss, surgical time, pre- and postoperative Nurick grades, Japanese Orthopaedic Association (JOA) scores, and complications.


All patients had single-level symptomatic TDHs. The patients presented with symptoms including thoracic myelopathy, axial back pain, urinary symptoms, and thoracic radiculopathy. Thoracic disc herniations involved levels T2–3 to T12–L1. Discs were classified as central or paracentral, and as calcified or noncalcified. All discs were successfully removed with no incidence of neural injury or CSF leak. The mean estimated blood loss was 523 ml, and the mean surgical time was 159 minutes. Nurick grades improved on average from 3.3 to 1.6. The mean JOA scores improved from 5.7 to 8.3 out of 11. The mean Hirabayashi recovery rate of the JOA score was 57%. All patients reported improvement in symptoms compared with preoperative status except for 1 patient with an American Spinal Injury Association Grade A spinal cord injury prior to surgery. The average duration of follow-up was 10.5 months. One patient developed postoperative wound infection that required additional operative debridement and revision of hardware.


Thoracic discectomy via a posterior pedicle-sparing transfacet approach is an adequate method of managing herniations at any thoracic level. The safety of the operation is significantly enhanced by the use of realtime intraoperative ultrasonography.

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Christopher K. Kepler, Alexander R. Vaccaro, Eric Chen, Alpesh A. Patel, Henry Ahn, Ahmad Nassr, Christopher I. Shaffrey, James Harrop, Gregory D. Schroeder, Amit Agarwala, Marcel F. Dvorak, Daryl R. Fourney, Kirkham B. Wood, Vincent C. Traynelis, S. Tim Yoon, Michael G. Fehlings and Bizhan Aarabi


In this clinically based systematic review of cervical facet fractures, the authors’ aim was to determine the optimal clinical care for patients with isolated fractures of the cervical facets through a systematic review.


A systematic review of nonoperative and operative treatment methods of cervical facet fractures was performed. Reduction and stabilization treatments were compared, and analysis of postoperative outcomes was performed. MEDLINE and Scopus databases were used. This work was supported through support received from the Association for Collaborative Spine Research and AOSpine North America.


Eleven studies with 368 patients met the inclusion criteria. Forty-six patients had bilateral isolated cervical facet fractures and 322 had unilateral isolated cervical facet fractures. Closed reduction was successful in 56.4% (39 patients) and 63.8% (94 patients) of patients using a halo vest and Gardner-Wells tongs, respectively. Comparatively, open reduction was successful in 94.9% of patients (successful reduction of open to closed reduction OR 12.8 [95% CI 6.1–26.9], p < 0.0001); 183 patients underwent internal fixation, with an 87.2% success rate in maintaining anatomical alignment. When comparing the success of patients who underwent anterior versus posterior procedures, anterior approaches showed a 90.5% rate of maintenance of reduction, compared with a 75.6% rate for the posterior approach (anterior vs posterior OR 3.1 [95% CI 1.0–9.4], p = 0.05).


In comparison with nonoperative treatments, operative treatments provided a more successful outcome in terms of failure of treatment to maintain reduction for patients with cervical facet fractures. Operative treatment appears to provide superior results to the nonoperative treatments assessed.

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Clinical outcomes research in spine surgery: what are appropriate follow-up times?

Presented at the 2018 AANS/CNS Joint Section on Disorders of the Spine and Peripheral Nerves

Oliver G. S. Ayling, Tamir Ailon, Greg McIntosh, Alex Soroceanu, Hamilton Hall, Andrew Nataraj, Christopher S. Bailey, Sean Christie, Alexandra Stratton, Henry Ahn, Michael Johnson, Jerome Paquet, Kenneth Thomas, Neil Manson, Y. Raja Rampersaud and Charles G. Fisher

In Brief

The time course required for the patient-reported outcomes of pain, physical function, and mental health to reach a recovery plateau after elective lumbar spine surgery was assessed utilizing a prospectively maintained multicenter registry. The work is important as it demonstrates that specific health dimensions follow different recovery plateaus and it provides evidence that a 2-year postoperative follow-up is not required to accurately assess the treatment effect of established surgeries for lumbar spinal pathologies.