All Publications

  • Utility of Adding Magnetic Resonance Imaging to Computed Tomography Alone in the Evaluation of Cervical Spine Injury: A Propensity-Matched Analysis. Spine Schoenfeld, A. J., Tobert, D. G., Le, H. V., Leonard, D. A., Yau, A. L., Rajan, P., Cho, C. H., Kang, J. D., Bono, C. M., Harris, M. B. 2018; 43 (3): 179?84


    Adult patients who received computed tomography (CT) alone or CT-magnetic resonance imaging (MRI) for the evaluation of cervical spine injury.To evaluate the utility of CT-MRI in the diagnosis of cervical spine injury using propensity-matched techniques.The optimal evaluation (CT alone vs. CT and MRI) for patients with suspected cervical spine injury in the setting of blunt trauma remains controversial.The primary outcome was the identification of a cervical spine injury, with decision for surgery and change in management considered secondarily. A propensity score was developed based on the likelihood of receiving evaluation with CT-MRI, and this score was used to balance the cohorts and develop two groups of patients around whom there was a degree of clinical equipoise in terms of the imaging protocol. Logistic regression was used to evaluate for significant differences in injury detection in patients evaluated with CT alone as compared to those receiving CT-MRI.Between 2007 and 2014, 8060 patients were evaluated using CT and 693 with CT-MRI. Following propensity-score matching, each cohort contained 668 patients. There were no significant differences between the two groups in baseline characteristics. The odds of identifying a cervical spine injury were significantly higher in the CT-MRI group, even after adjusting for prior injury recognition on CT (odds ratios 2.6; 95% confidence interval 1.7-4.0; P?

    View details for DOI 10.1097/BRS.0000000000002285

    View details for PubMedID 28632646

  • The effect of short (2-weeks) versus long (6-weeks) post-operative restrictions following lumbar discectomy: a prospective randomized control trial EUROPEAN SPINE JOURNAL Bono, C. M., Leonard, D. A., Cha, T. D., Schwab, J. H., Wood, K. B., Harris, M. B., Schoenfeld, A. J. 2017; 26 (3): 905-912
  • Relationship between size of disc and early postoperative outcomes after lumbar discectomy. Archives of orthopaedic and trauma surgery En'Wezoh, D. C., Leonard, D. A., Schoenfeld, A. J., Harris, M. B., Zampini, J. M., Bono, C. M. 2017; 137 (6): 805?11


    Previous studies suggest that patients with larger disc herniations (greater than 6 mm) will have better outcomes following discectomy. This has not been validated in a large series of patients.We sought to empirically evaluate this relationship in a series of patients who had data collected prospectively as part of a randomized trial.This retrospective review included 63 consecutive adult patients who underwent a single-level, primary lumbar discectomy. Outcomes were VAS for leg and back pain and the modified oswestry disability index (MODI). Statistical tests were used to compare patients using different cutoffs of preoperative disc diameters and disc volume removed. Regression analysis was performed to determine if there was a relationship between outcomes and the measured parameters.While patients who achieved substantial clinical benefit (SCB) for MODI had larger disc diameters, this relationship was not found for leg or back pain for any of the measured parameters. Using 5, 6, 7, or 8 mm as a cutoff for disc diameter demonstrated no differences. Regression analysis did not demonstrate a significant relationship between disc volume removed and final MODI scores.While patients with larger disc herniations on average might have a greater likelihood of superior clinical outcomes, the previously suggested "6 mm rule" was not supported.

    View details for DOI 10.1007/s00402-017-2699-6

    View details for PubMedID 28455675

  • The prognostic value of preoperative participation in activities of daily living on postoperative outcomes following lumbar discectomy. Clinical neurology and neurosurgery Leonard, D. A., Schoenfeld, A. J., Harris, M. B., Bono, C. M. 2017; 155: 40?44


    In other surgical fields, preoperative level of participation in activities of daily living (ADLs) has been found to be important in predicting outcomes. To date, postoperative ADL measurements have only been used to characterize outcomes following lumbar discectomy. The present study's goal was to determine if patients' preoperative ability to perform ADLs correlates with their postoperative outcomes after lumbar discectomy at 3 months and 1 year.This retrospective study was performed using prospectively collected data from patients prospectively enrolled in a randomized clinical trial. All patients were 18 years or older, spoke English, had not previously had lumbar surgery, and underwent discectomy for a single-level lumbar disc herniation. Oswestry disability index (ODI) and visual analogue scale (VAS) back and leg pain scores were collected preoperatively and at 3 months and 1 year postoperatively. Simple linear regression analysis was performed to detect any significant correlations between three preoperative ODI domain values and postoperative scores. Additionally, regression analysis was used to determine the correlation between the preoperative ODI domains and percentage of good and poor outcomes, where an improvement of at least 18.8 points for ODI and at least 2 points for VAS constituted a good outcome.90 subjects satisfied inclusion criteria (average age 42, 53 males, 37 females). Patients' ability to take care of themselves and to stand preoperatively were correlated with improvement in ODI postoperatively, with worse ability corresponding to more improvement (p<0.001 for both). Only personal care scores correlated with good improvement in leg pain. No significant correlations were found with back pain. When evaluating patients by dichotomized outcome (good or poor), only preoperative ability to participate in personal care was consistently significantly correlated to a good outcome.This is the first study to suggest that lower preoperative ability to take part in personal care might predict better surgical outcomes after discectomy. The current data might prompt reassessment of the importance of ADLs in pre-operative patient evaluation and may help anticipate outcomes following lumbar discectomy.

    View details for DOI 10.1016/j.clineuro.2017.02.010

    View details for PubMedID 28254514

  • The effect of chronic liver disease on acute outcomes following cervical spine trauma. The spine journal : official journal of the North American Spine Society Bessey, J. T., Le, H. V., Leonard, D. A., Bono, C. M., Harris, M. B., Kang, J. D., Schoenfeld, A. J. 2016; 16 (10): 1194?99


    The adverse impact of chronic liver diseases, including chronic hepatitis and cirrhosis, on outcomes following orthopedic surgery has been increasingly recognized in recent years. The impact of these conditions on acute outcomes following spinal trauma remains unknown.This is a cohort control study that uses patient records in the Massachusetts Statewide Inpatient Dataset (2003-2010).The study aimed to evaluate whether chronic liver disease increased the odds of mortality, complications, failure to rescue (FTR), reoperation, and hospital length of stay (LOS) following cervical spine trauma.The sample is composed of 10,841 patients with cervical spine trauma.Posttreatment morbidity, mortality, reoperation, and LOS were the outcome measures.Differences between patients with and without chronic liver disease were evaluated using chi-square or Wilcoxon rank-sum tests. Logistic and negative binomial regression techniques were used to adjust for confounders, including whether a surgical intervention was performed. Receiver operator characteristic curves were used to assess final model discrimination.There were 117 patients with chronic liver disease identified in the cohort. The rate of surgical intervention for cervical trauma was not significantly different between patients with and without chronic liver disease (odds ratio [OR]: 0.82, 95% confidence interval [CI]: 0.52-1.29). Mortality (OR: 2.12, 95% CI: 1.23-3.66), FTR (OR: 2.86, 95% CI: 1.34-6.11), complications (OR: 1.65, 95% CI: 1.12-2.45), and LOS (regression coefficients: 0.31, 95% CI: 0.14-0.48) were all significantly increased for patients with chronic liver disease in final adjusted models that controlled for differences in case-mix and whether a surgical procedure was performed. Final models explained approximately 72% of the variation in mortality and FTR.Our novel findings indicate that patients with chronic liver disease may be at elevated risk of posttreatment morbidity and mortality following cervical spine trauma. Medical comanagement in the acute period following injury and optimization before surgery may diminish the potential for adverse events.

    View details for DOI 10.1016/j.spinee.2016.06.001

    View details for PubMedID 27288882

  • Answer to the Letter to the Editor of M. D. Sewell et al. concerning "Virtually bloodless posterior midline exposure of the lumbar spine using the 'para-midline' fatty plane" by Moghimi MH, Leonard DA, Cho CH, Schoenfeld AJ, Phan P, Harris MB, Bono CM: Eur Spine J (2016) 25;956-962. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society Moghimi, M. H., Leonard, D. A., Cho, C. H., Schoenfeld, A. J., Phan, P., Harris, M. B., Bono, C. M. 2016; 25 (9): 3012?13

    View details for DOI 10.1007/s00586-016-4575-4

    View details for PubMedID 27160825

  • Predictors of 30- and 90-Day Survival Following Surgical Intervention for Spinal Metastases: A Prognostic Study Conducted at Four Academic Centers. Spine Schoenfeld, A. J., Leonard, D. A., Saadat, E., Bono, C. M., Harris, M. B., Ferrone, M. L. 2016; 41 (8): E503?9


    A retrospective review.We sought to use data from 4 tertiary medical centers to explore surgical, medical, and demographic factors that influence survival within the first 90 days following surgery for spinal metastases.Over the last 2 decades, patients with spinal metastases have become more likely to receive surgical intervention. The impact of surgical intervention and its potential benefits must be weighed against the risk of complications and peri-operative mortality. Risk factors that elevate the risk of mortality in the acute postoperative period are not well understood.All records of patients who underwent surgery for metastatic spinal disease at 1 of 4 academic medical centers in New England from 2007 to 2013 were obtained. Patient demographics, tumor characteristics, medical comorbidities, nutritional and functional status, as well as surgical variables were abstracted. Mortality was assessed for patients at 30 and 90 days following the procedure. Factors predictive of survival were assessed using bivariate logistic regression. Those factors with P values?

    View details for DOI 10.1097/BRS.0000000000001273

    View details for PubMedID 27064339

  • Idiopathic Spinal Epidural Lipomatosis in the Lumbar Spine. Orthopedics Al-Omari, A. A., Phukan, R. D., Leonard, D. A., Herzog, T. L., Wood, K. B., Bono, C. M. 2016; 39 (3): 163?68


    Overgrowth of epidural fat, known as spinal epidural lipomatosis (SEL), can cause symptomatic compression of the spinal cord, conus medullaris, or cauda equina. Suggested predisposing factors such as obesity, steroid use, and diabetes mellitus have been based on a few reported cases, many of which were not surgically confirmed. There is a paucity of epidemiological data in surgically confirmed cases for this disorder. The purpose of this independently reviewed, retrospective, matched cohort analysis was to compare the demographics and incidence of comorbidities of patients who underwent lumbar decompression for SEL vs degenerative stenosis without SEL. Two surgeons' databases were reviewed to identify patients older than 18 years who underwent decompression surgery for magnetic resonance imaging-verified, symptomatic lumbar SEL. A matched control group comprised an equal number of patients with degenerative stenosis (n=14). Demographic data, body mass index, symptom type/duration, comorbidities, complications, treatment history, and associated pathology were collected from medical records. Previously suggested risk factors, such as obesity, endocrinopathy, and epidural steroid injections, were not significantly different between the SEL and control groups. Furthermore, there were no differences in operative times, complications, or blood loss. The only noted difference between the 2 groups was the preoperative duration of symptoms, on average double in patients with SEL. This series represents the largest of its kind reported to date. Because symptom duration was the only difference noted, it is postulated to be the result of lack of awareness of SEL. Future prospective study in a larger group of patients is warranted. [Orthopedics. 2016; 39(3):163-168.].

    View details for DOI 10.3928/01477447-20160315-04

    View details for PubMedID 27018608

  • The importance of fluency of terminology in the applicability of imaging findings. The spine journal : official journal of the North American Spine Society Cho, C. H., Leonard, D. A. 2016; 16 (1): 61?62


    Fu MC, Webb ML, Buerba RA, Neway WE, Brown JE, Trivedi M, et al. Comparison of agreement of cervical spine degenerative pathology findings in magnetic resonance imaging studies. Spine J 2016:16:42-8 (in this issue).

    View details for DOI 10.1016/j.spinee.2015.09.065

    View details for PubMedID 26706218

  • Virtually bloodless posterior midline exposure of the lumbar spine using the "para-midline" fatty plane. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society Moghimi, M. H., Leonard, D. A., Cho, C. H., Schoenfeld, A. J., Phan, P., Harris, M. B., Bono, C. M. 2016; 25 (3): 956?62


    The authors have developed a "para-midline" approach to the posterior lumbar spine using a virtually avascular surgical plane not previously described in the literature. It was their purpose to document consistent MRI presence of this plane and to prospectively evaluate its clinical use in terms of blood loss.Fifty consecutive patients undergoing primary lumbar surgery on 1-3 levels were prospectively enrolled from September 2014 to May 2015. The para-midline approach was used in all cases. The deep lumbar fascia is longitudinally incised on either side of the spinous processes instead of directly in the midline, which reveals the para-midline fatty plane. Blood loss during the approach and overall blood loss were recorded for all patients. MRIs from each patient were reviewed by an experienced neuroradiologist to determine the presence of the para-midline fatty plane.There was no recorded blood loss during the approach for all procedures. The average overall blood loss was 60 cc (20-200 cc). No patient required a transfusion intraoperatively or postoperatively. The fatty para-midline plane was noted on preoperative MRI at all operated levels in all patients. The average width of this plane was 6.5 mm (2-17 mm).The para-midline approach for lumbar surgery is associated with less blood loss than traditional, subperiosteal exposure techniques. The fatty interval through which this approach is made is universally present and identifiable on MRI. The authors offer this approach as a means of decreasing the risks associated with blood loss and transfusion with posterior lumbar surgery.

    View details for DOI 10.1007/s00586-015-4319-x

    View details for PubMedID 26582166

  • Assessing the utility of a clinical prediction score regarding 30-day morbidity and mortality following metastatic spinal surgery: the New England Spinal Metastasis Score (NESMS). The spine journal : official journal of the North American Spine Society Schoenfeld, A. J., Le, H. V., Marjoua, Y., Leonard, D. A., Belmont, P. J., Bono, C. M., Harris, M. B. 2016; 16 (4): 482?90


    The New England Spinal Metastasis Score (NESMS) was recently proposed to help predict 1-year survival following surgery for spinal metastases. Its ability to predict short-term outcomes, including 30-day morbidity, mortality, and hospital length of stay, has not been evaluated.Assess the capacity of NESMS to predict 30-day morbidity and mortality, as well as hospital length of stay, following surgery for spinal metastases.Validation study.All patients who had undergone spinal surgery with a history of metastatic spinal disease within the National Surgical Quality Improvement Program (NSQIP; 2007-2013).Mortality, complications, failure to rescue, and length of stay.Demographic, oncologic, laboratory, and surgical data were obtained from the NSQIP. All patients were assigned an NESMS score (0-3). The effect of the NESMS score on the outcomes of interest was assessed using multivariable logistic regression and negative binomial regression that controlled for confounders. Final model discrimination and calibration were assessed using the c-statistic and Hosmer-Lemeshow test, respectively. Internal validation was performed using a bootstrapping procedure.NSQIP data on 776 patients were included in this analysis. The 30-day mortality rate was 11% (N=87), and 51% of patients (N=395) sustained one or more complications. The final adjusted model demonstrated that the NESMS was a statistically significant predictor of 30-day mortality (p<.001), major systemic complications (p<.001), and failure to rescue (p=.03) following metastatic spinal surgery. Patients with an NESMS score of 3 had an 89% reduction in mortality (95% confidence interval [CI]: 0.04, 0.31), a 74% reduction in major systemic complications (95% CI: 0.11, 0.62), and an 88% reduction in failure to rescue (95% CI: 0.03, 0.47) as compared with those with a score of 0. The final model explained 71% of the variation in 30-day mortality. Findings were unchanged in the bootstrap analysis performed among 77,600 patient replicates.This study demonstrates the clinical accuracy of the NESMS score for predicting short-term major morbidity and mortality following metastatic spinal surgery. The success of this score in an independent cohort of patients collected from centers across the United States indicates its potential for translation to clinical practice.

    View details for DOI 10.1016/j.spinee.2015.09.043

    View details for PubMedID 26409416

  • The influence of adjacent level disc disease on discectomy outcomes. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society Briseño, M. R., Phukan, R. D., Leonard, D. A., Herzog, T. L., Cho, C. H., Schwab, J. H., Wood, K. B., Bono, C. M., Cha, T. D. 2016; 25 (1): 230?34


    The state of adjacent level discs and its impact on surgical outcomes following single-level lumbar discectomy have not been previously investigated. The purpose of the present study was to determine if a significant relationship exists between the degree of preoperative adjacent level disc degeneration and post-operative clinical outcomes following lumbar discectomy.This study retrospectively used preoperative magnetic resonance imaging (MRI) and prospectively collected data from a randomized clinical trial at two tertiary-care academic hospitals. Patients who underwent a primary, single-level lumbar discectomy were included. Exclusion criteria included prior lumbar surgery. Outcome measures were the Modified Oswestry Disability Index (ODI) score and Visual Analog Scale (VAS) scores for back and leg pain. These were recorded at baseline and at 3 months, 1, and 2 years postoperatively. An independent reviewer graded adjacent level disc degeneration on all preoperative MRIs using the Pfirrmann grading scale. These data were then analyzed for correlation with each outcome measure.Forty-seven patients were included in the study. No statistically significant correlations were found when comparing preoperative 3-month or 1-year postoperative scores or change from baseline of any outcome measure between Pfirrmann grades. Only about half the patients had 2-year follow-up, but at that time point a statistically significant difference in back VAS scores was observed between Pfirrmann groups. No other significant differences were observed at that point.The degree of preoperative adjacent level degeneration does not significantly affect functional or pain relief outcomes following lumbar discectomy up to 1 year after surgery.

    View details for DOI 10.1007/s00586-015-4200-y

    View details for PubMedID 26363560

  • Modeling 1-year survival after surgery on the metastatic spine. The spine journal : official journal of the North American Spine Society Ghori, A. K., Leonard, D. A., Schoenfeld, A. J., Saadat, E., Scott, N., Ferrone, M. L., Pearson, A. M., Harris, M. B. 2015; 15 (11): 2345?50


    Choosing appropriate surgical patients in the setting of spinal metastases can be challenging. Existing scoring systems focus primarily on patient selection or operative techniques. These scores are limited in their capacity to predict postoperative survival.The aim was to model survival after spine surgery for metastastic disease.This was a retrospective multicenter study.All patients who had undergone surgery for the treatment of metastatic spinal disease at one of four tertiary care centers between 2007 and 2013 were included.The outcome measure was 1-year survival after surgery.Demographic, medical, oncologic, surgical, and survival data were abstracted from medical records. The effect of predictor variables on survival was evaluated alone and in combination using stepwise logistic regression. Multivariable logistic regression was subsequently used to adjust for confounders. A predictive score was then developed and compared against that of the modified Bauer score alone in terms of prognosticating 1-year survival after surgery.In the time period under investigation, 318 patients underwent surgical intervention for metastastic disease involving the spine, with 307 having data available for analysis. The survival rate at 1 year was 48% (n=142), with a median survival of 10 months. In final adjusted analysis, preoperative modified Bauer score (odds ratio [OR] 3.00; 95% confidence interval [CI] 1.80-5.01; p<.001), ambulatory status (OR 2.47; 95% CI 1.48-4.14; p=.001), and serum albumin (OR 2.80; 95% CI 1.66-4.72; p<.001) were all independent predictors of 1-year survival. The most parsimonious model weighted the modified Bauer score with 2 points and intact ambulatory status and normal serum albumin level with 1 point each, with a ceiling score of 3. The final model using the predictive score was able to explain 74% of the variation in 1-year survival. In contrast, the modified Bauer score alone was only able to explain 64% of the variation in 1-year survival.This study demonstrates the importance of including factors related to the overall health of a patient, in addition to parameters surrounding their cancer diagnosis, to better prognosticate survival. Our predictive score performed better than the modified Bauer alone and may be used to predict survival after surgical intervention for metastatic disease.III.

    View details for DOI 10.1016/j.spinee.2015.06.061

    View details for PubMedID 26160329

  • Validation of multisociety combined task force definitions of abnormal disk morphology. AJNR. American journal of neuroradiology Cho, C. H., Hsu, L., Ferrone, M. L., Leonard, D. A., Harris, M. B., Zamani, A. A., Bono, C. M. 2015; 36 (5): 1008?13


    The multisociety task force descriptively defined abnormal lumbar disk morphology. We aimed to use their definitions to provide a higher level of evidence for the validation of MR imaging in the evaluation of this pathology in patients who have undergone diskectomy by retrospectively classifying their preoperative MRI.This retrospective, institutional review board-approved study included 54 of 86 consecutive patients (47 men; average age, 44 years) enrolled in an ongoing prospective trial of surgically treated lumbar disk herniation who had preoperative MRI and documented intraoperative classification of the abnormal disk as protrusion, extrusion, or sequestration by the treating surgeon. Preoperative MRI was classified by 2 blinded radiologists; discrepancies were resolved by a third reader. Statistical analysis of interobserver agreement and imaging compared with surgical findings was performed.The readers disagreed on only 1 of the 54 cases. The third reader resolved the disagreement. Eight protrusions and 46 extrusions were found on imaging, with no sequestrations. At surgery, there were 13 protrusions and 40 extrusions, with 2 of the extrusions also containing sequestrations; the remaining case had only sequestration. There were 16 discrepancies between imaging and surgery, resulting in 70% agreement.This study, which was intended to validate the multisociety combined task force definitions of abnormal disk morphology by using MR imaging with a surgical criterion standard, found 70% agreement between imaging diagnosis and surgical findings. Although reasonable, this finding highlights differences that often exist between intraoperative and preoperative imaging findings of lumbar disk herniation.

    View details for DOI 10.3174/ajnr.A4212

    View details for PubMedID 25742982

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