Sohail K Mirza

Dartmouth–Hitchcock Medical Center, LEB, New Hampshire, United States

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Publications (115)413.61 Total impact

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    ABSTRACT: Use of Bone Morphogenetic Protein (BMP) as an adjunct to spinal fusion surgery proliferated following Food and Drug Administration (FDA) approval in 2002. Major safety concerns emerged in 2008. To examine whether published concerns about the safety of BMP altered clinical practice. Analysis of the National Inpatient Sample from 2002 through 2012. Adults (age >20) undergoing an elective fusion operation for common degenerative diagnoses, identified using codes from the International Classification of Diseases, 9(th)revisions, Clinical Modification (ICD-9-CM). Proportion of cervical and lumbar fusion operations, over time, that involved BMP. We aggregated the data into a monthly time series and reported the proportion of cervical and lumbar fusion operations, over time, that involved BMP. Auto Regressive Integrated Moving Average, a regression model for time series data, was used to test whether there was a statistically significant change in the overall rate of BMP use following a FDA Public Health Notification in 2008. The study was funded by federal research grants, and no investigator had any conflict of interests. Use of BMP in spinal fusion procedures increased rapidly until 2008, involving up to 45.2% of lumbar and 13.5% of cervical fusions. BMP use significantly decreased following the 2008 FDA Public Health Notification and revelations of financial payments to surgeons involved in the pivotal FDA approval trials. For lumbar fusion, the average annual increase was 7.9 percentage points per year from 2002 to 2008, followed by an average annual decrease of 11.7 percentage points thereafter (p = <0.001). Use of BMP in cervical fusion increased 2.0% per year until the FDA Notification, followed by a 2.8% per year decrease (p = 0.035). Use of BMP in spinal fusion surgery declined subsequent to published safety concerns and revelations of financial conflicts-of-interest for investigators involved in the pivotal clinical trials. Copyright © 2014 Elsevier Inc. All rights reserved.
    The spine journal: official journal of the North American Spine Society 12/2014; 15(4). DOI:10.1016/j.spinee.2014.12.010 · 2.80 Impact Factor
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    10/2014: chapter A Dartmouth Atlas of Health Care Series;
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    ABSTRACT: The Spine Patient Outcomes Research Trial aimed to determine the comparative effectiveness of surgical care versus nonoperative care by measuring longitudinal values: outcomes, satisfaction, and costs.
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    ABSTRACT: Study Design. Retrospective analysis of Medicare claims linked to a multi-center clinical trial.Objective. The Spine Patient Outcomes Research Trial (SPORT) provided a unique opportunity to examine the validity of a claims-based algorithm for grouping patients by surgical indication. SPORT enrolled patients for lumbar disc herniation, spinal stenosis, and degenerative spondylolisthesis. We compared the surgical indication derived from Medicare claims to that provided by SPORT surgeons, the "gold standard".Summary of Background Data. Administrative data are frequently used to report procedure rates, surgical safety outcomes, and costs in the management of spinal surgery. However, the accuracy of using diagnosis codes to classify patients by surgical indication has not been examined.Methods. Medicare claims were link to beneficiaries enrolled in SPORT. The sensitivity and specificity of three claims-based approaches to group patients based on surgical indications were examined: 1) using the first listed diagnosis; 2) using all diagnoses independently; and 3) using a diagnosis hierarchy based on the support for fusion surgery.Results. Medicare claims were obtained from 376 SPORT participants, including 21 with disc herniation, 183 with spinal stenosis, and 172 with degenerative spondylolisthesis. The hierarchical coding algorithm was the most accurate approach for classifying patients by surgical indication, with sensitivities of 76.2%, 88.1%, and 84.3% for disc herniation, spinal stenosis, and degenerative spondylolisthesis cohorts, respectively. The specificity was 98.3% for disc herniation, 83.2% for spinal stenosis, and 90.7% for degenerative spondylolisthesis. Misclassifications were primarily due to codes attributing more complex pathology to the case.Conclusion. Standardized approaches for using claims data to accurately group patients by surgical indications has widespread interest. We found that a hierarchical coding approach correctly classified over 90% of spine patients into their respective SPORT cohorts. Therefore, claims data appears to be a reasonably valid approach to classifying patients by surgical indication.
    Spine (Philadelphia, Pa.: 1986) 04/2014;
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    ABSTRACT: Study Design. Retrospective analysis of Medicare claims linked to a multi-center clinical trial.Objective. The Spine Patient Outcomes Research Trial (SPORT) provided a unique opportunity to examine the validity of a claims-based algorithm for grouping patients by surgical indication. SPORT enrolled patients for lumbar disc herniation, spinal stenosis, and degenerative spondylolisthesis. We compared the surgical indication derived from Medicare claims to that provided by SPORT surgeons, the "gold standard".Summary of Background Data. Administrative data are frequently used to report procedure rates, surgical safety outcomes, and costs in the management of spinal surgery. However, the accuracy of using diagnosis codes to classify patients by surgical indication has not been examined.Methods. Medicare claims were link to beneficiaries enrolled in SPORT. The sensitivity and specificity of three claims-based approaches to group patients based on surgical indications were examined: 1) using the first listed diagnosis; 2) using all diagnoses independently; and 3) using a diagnosis hierarchy based on the support for fusion surgery.Results. Medicare claims were obtained from 376 SPORT participants, including 21 with disc herniation, 183 with spinal stenosis, and 172 with degenerative spondylolisthesis. The hierarchical coding algorithm was the most accurate approach for classifying patients by surgical indication, with sensitivities of 76.2%, 88.1%, and 84.3% for disc herniation, spinal stenosis, and degenerative spondylolisthesis cohorts, respectively. The specificity was 98.3% for disc herniation, 83.2% for spinal stenosis, and 90.7% for degenerative spondylolisthesis. Misclassifications were primarily due to codes attributing more complex pathology to the case.Conclusion. Standardized approaches for using claims data to accurately group patients by surgical indications has widespread interest. We found that a hierarchical coding approach correctly classified over 90% of spine patients into their respective SPORT cohorts. Therefore, claims data appears to be a reasonably valid approach to classifying patients by surgical indication.
    Spine 02/2014; 39(9). DOI:10.1097/BRS.0000000000000275 · 2.45 Impact Factor
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    ABSTRACT: Safety information in spine surgery is important for informed patient choice and performance-based payment incentives, but measurement methods for surgical safety assessment are not standardized. Published reports of complication rates for common spinal procedures show wide variation. Factors influencing variation may include differences in safety ascertainment methods and procedure types. In a prospective cohort study, adverse events were observed in all patients undergoing spine surgery at two hospitals during a 2-year period. Multiple processes for adverse occurrence surveillance were implemented, and the associations between surveillance methods, surgery invasiveness, and observed frequencies of adverse events were examined. The study enrolled 1,723 patients. Adverse events were noted in 48.3% of the patients. Reviewers classified 25% as minor events and 23% as major events. Of the major events, the daily rounding team reported 38.4% of the events using a voluntary reporting system, surgeons reported 13.4%, and 9.1% were identified during clinical conferences. A review of medical records identified 86.7% of the major adverse events. The adverse events occurred during the inpatient hospitalization for 78.1% of the events, within 30 days for an additional 12.5%, and within the first year for the remaining 9.4%. A unit increase in the invasiveness index was associated with an 8.2% increased risk of a major adverse event. A Current Procedural Terminology-based algorithm for quantifying invasiveness correlated well with medical records-based assessment. Increased procedure invasiveness is associated with an increased risk of adverse events. The observed frequency of adverse events is influenced by the ascertainment modality. Voluntary reports by surgeons and other team members missed more than 50% of the events identified through a medical records review. Increased surgery invasiveness, measured from medical records or billing codes, is quantitatively associated with an increased risk of adverse events.
    Instructional course lectures 01/2014; 63:271-86.
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    ABSTRACT: In response to increasing use of lumbar fusion for improving back pain, despite unclear efficacy, particularly among injured workers, some insurers have developed limited coverage policies. Washington State's workers' compensation (WC) program requires imaging confirmation of instability and limits initial fusions to a single level. In contrast, California requires coverage if a second opinion supports surgery, allows initial multilevel fusion, and provides additional reimbursement for surgical implants. There are no studies that compare population-level effects of these policy differences on utilization, costs, and safety of lumbar fusion.
    The spine journal: official journal of the North American Spine Society 11/2013; 14(7). DOI:10.1016/j.spinee.2013.08.018 · 2.80 Impact Factor
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    ABSTRACT: Purpose: There is no universally accepted standard of care for lumbar spinal stenosis. Several studies suggest surgical care results in better outcomes than conservative care, but the type of surgery (decompression vs. fusion) remains controversial. Interspinous spacer devices (“spacers”) have emerged as a new initial treatment alternative. Our objective was to assess the cost-effectiveness of spacers for lumbar stenosis and to identify thresholds for post-spacer health utility that would result in spacers being a cost-effective initial surgery. Method: A Markov model tracked health utility and costs for a hypothetical 65-year-old cohort followed over a 10-year time horizon under six care strategies: conservative care (C) and five surgical strategies defined by initial and up to two subsequent surgeries involving spacer (S), decompression (D), and/or fusion (F): S-D-D, S-D-F, S-F-F, D-D-F, and D-F-F. Incremental cost-effectiveness ratios (ICER) reported as cost per quality-adjusted life year (QALY) gained included direct medical costs for surgery (initial S: $8,227; D: $5,925; F: $20,101). Medicare claims data were used to estimate costs, complication rates (S: 4.8%; D: 6.6%; F: 9.4%) and reoperation within 3 years (S: 20.1%; D: 10.8%; F: 14%) for each surgery. Utilities were derived from published studies (C:0.71; S: 0.82; D: 0.77; F:0.74). Reoperation rates after 3 years for D and F were obtained from the literature. Spacer failure beyond 3 years is uncertain and was evaluated through sensitivity analyses. In the base-case, the spacer failure rate was held constant for years 4-10 (cumulative: 47%). In subsequent analyses, the 10-year failure rate was increased either moderately (to 56%) or steeply (to 90%). Additionally, since utility following spacer surgery is rarely reported, we performed threshold analyses on post-spacer utility to determine when spacer surgery fails to be cost-effective either because it is dominated or has an ICER> $100,000. Result: An initial spacer strategy (S-D-D) emerged as the most cost-effective ($14,400 per QALY gained) in base-case analyses. The ICER rose minimally ($16,800) when the failure rate was increased steeply. Spacer surgery remained cost-effective for post-spacer utilities ≥0.7695 in the base case and ≥0.773 under steeply increased failure. Conclusion: Post-spacer health utilities in the literature to date exceed the identified thresholds, suggesting that interspinous spacer devices are reasonably cost-effective when implemented as a first surgical intervention for patients with spinal stenosis.
    The 35th Annual Meeting of the Society for Medical Decision Making; 10/2013
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    ABSTRACT: The clinical entity "discogenic back pain" remains controversial at fundamental levels, including its pathophysiology, diagnostic criteria, and optimal treatment. This is true despite availability of four randomized trials comparing the efficacy of surgical and nonsurgical treatments. One trial showed benefit for lumbar fusion compared with unstructured nonoperative care, and three others showed roughly similar results for lumbar surgery and structured rehabilitation. To compare outcomes of community-based surgical and nonsurgical treatments for patients with chronic back pain attributed to degeneration at one or two lumbar disc levels. Prospective observational cohort study. Patients presenting with axial back pain to academic and private practice orthopedic surgeons and neurosurgeons in a large metropolitan area. Roland-Morris back disability score (primary outcome), current rating of overall pain severity on a numerical scale, back and leg pain bothersomeness measures, the physical function scale of the short-form 36 version 2 questionnaire, use of medications for pain, work status, emergency department visits, hospitalizations, and further surgery. Patients receiving spine surgery within 6 months of enrollment were designated as the "surgical treatment" group and the remainder as "nonsurgical treatment." Outcomes were assessed at 3, 6, 9, and 12 months after enrollment. We enrolled 495 patients with discogenic back pain presenting for initial surgical consultation in offices of 16 surgeons. Eighty-six patients (17%) had surgery within 6 months of enrollment. Surgery consisted of instrumented fusion (79%), disc replacement (12%), laminectomy, or discectomy (9%). Surgical patients reported more severe pain and physical disability at baseline and were more likely to have had prior surgery. Adjusting for baseline differences among groups, surgery showed a limited benefit over nonsurgical treatment of 5.4 points on the modified (23-point) Roland disability questionnaire (primary outcome) 1 year after enrollment. Using a composite definition of success incorporating 30% improvement in the Roland score, 30% improvement in pain, no opioid pain medication use, and working (if relevant), the 1-year success rate was 33% for surgery and 15% for nonsurgical treatment. The rate of reoperation was 11% in the surgical group; the rate of surgery after treatment designation in the nonsurgical group was 6% at 12 months after enrollment. The surgical group showed greater improvement at 1 year compared with the nonsurgical group, although the composite success rate for both treatment groups was only fair. The results should be interpreted cautiously because outcomes are short term, and treatment was not randomly assigned. Only 5% of nonsurgical patients received cognitive behavior therapy. Nonsurgical treatment that patients received was variable and mostly not compliant with major guidelines.
    The spine journal: official journal of the North American Spine Society 07/2013; 13(11). DOI:10.1016/j.spinee.2013.05.047 · 2.80 Impact Factor
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    ABSTRACT: Study Design. Retrospective cohort analysis of Medicare claims for 2006-2009.Objective. To examine whether interspinous distraction procedures are used selectively in patients with more advanced age or comorbidity; and whether they are associated with fewer complications, lower costs, and less revision surgery than laminectomy or fusion surgery.Summary of Background Data. A manufacturer-sponsored randomized trial suggested an advantage of interspinous spacer surgery over non-surgical care, but there are few comparisons with other surgical procedures. Furthermore, there are few population-based data evaluating patterns of use of these devices.Methods. We used Medicare inpatient claims data to compare age and comorbidity for patients with spinal stenosis having surgery (n = 99,084) with (1) an interspinous process spacer alone; (2) laminectomy and a spacer; (3) decompression alone; or (4) lumbar fusion (1-2 level). We also compared these four groups for cost of surgery and rates of revision surgery, major medical complications, wound complications, mortality, and 30-day readmission rates.Results. Patients who received spacers were older than those receiving decompression or fusion, but had little evidence of greater comorbidity. Patients receiving a spacer alone had fewer major medical complications than those undergoing decompression or fusion surgery (1.2% versus 1.8% and 3.3% respectively), but had higher rates of further inpatient lumbar surgery (16.7% versus 8.5% for decompression and 9.8% for fusion at 2 years). Hospital payments for spacer surgery were greater than for decompression alone, but less than for fusion procedures. These associations persisted in multivariate models adjusting for patient age, sex, comorbidity score, and previous hospitalization.Conclusion. Compared to decompression or fusion, interspinous distraction procedures pose a trade-off in outcomes: fewer complications for the index operation, but higher rates of revision surgery. This information should help patients make more informed choices, but further research is needed to define optimal indications for these new devices.
    Spine 01/2013; DOI:10.1097/BRS.0b013e31828631b8 · 2.45 Impact Factor
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    ABSTRACT: Purpose: Treatment options for lumbar spinal stenosis include surgical and non-surgical approaches. Decision support in the form of coaching may help patients deliberate about their treatment options. The goal of this study is to assess the impact of coaching on the decision process for patients considering their treatment options for spinal stenosis. Method: Patients with spinal stenosis referred by a spine specialist for decision support are randomly assigned to either: decision aid (DA only, usual care) or decision aid + health coaching by telephone (DA+HC, intervention group). Enrolled participants complete questionnaires at: baseline, after watching the video decision aid, at two weeks after DA, and at 6 months. Measures - patient demographic characteristics (age, gender, and education), stage of decision making, treatment choice, treatments received, and decisional regret. Result: To date, 117 participants have completed baseline and follow up questionnaires (58 DA only / 59 DA+HC). Average age 67.1 years, 49% female, 60% had at least some college. Both groups showed similar progress in decision making after watching the DA (Table 1). More patients in the coaching group had made a treatment decision at the two week follow up (DA+HC 75% vs. DA only 48%, p=0.001). The uptake of surgery was similar for both groups (DA only (11/58 - 19%) had surgery vs. DA+HC (12/59 - 20%); however at the 6 month follow-up point more coaching participants had implemented the treatment chosen at 2 weeks (64% of DA only participants followed through with their choice vs. 80% of DA+HC patients, p=0.03). Few patients indicated regret about their treatment (DA only, 5% vs. DA+HC 7%) at 6-month follow up. Conclusion: The preliminary results from this ongoing study suggest similar treatment uptake and low levels of regret with treatment choice for both study groups. The addition of a telephone coaching session appears to help some participants arrive at a decision more quickly and follow through with their chosen option.
    The 34th Annual Meeting of the Society for Medical Decision Making; 10/2012
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    ABSTRACT: Study Design. Retrospective review of a prospectively collected databaseObjective. To examine whether short- and long-term outcomes after surgery for SPS and DS vary across centers.Summary of Background Data. Surgery has been shown to be of benefit for both lumbar stenosis (SPS) and degenerative spondylolisthesis (DS). For both conditions, surgery often consists of laminectomy with or without fusion. Potential differences in outcomes of these overlapping procedures across various surgical centers have not yet been investigated.Methods. Spine Patient Outcomes Research Trial cohort participants with a confirmed diagnosis of SPS or DS undergoing surgery were followed from baseline at 6 weeks, and 3, 6 and 12 months, and yearly thereafter, at 13 spine clinics in 11 US states. Baseline characteristics and short- and long-term outcomes were analyzed.Results. 793 patients underwent surgery. Significant differences were found between centers with regard to patient race, body mass index, treatment preference, neurological deficit, stenosis location, severity and number of stenotic levels. Significant differences were also found in operative duration and blood loss, the incidence of durotomy, the length of hospital stay, and wound infection. When baseline differences were adjusted for, significant differences were still seen between centers in changes in patient functional outcome (SF-36 bodily pain and physical function, and Oswestry disability index) at 1 year after surgery. In addition, the cumulative adjusted change in Oswestry disability index score at 4 years significantly differed among centers, with SF-36 scores trending towards significance.Conclusions. There is broad and statistically significant variation in short- and long-term outcomes after surgery for SPS and DS across various academic centers, when statistically significant baseline differences are adjusted for. The findings suggest choice of center affects outcome after these procedures, although further studies are required to investigate which center characteristics are most important.
    Spine 10/2012; 38(8). DOI:10.1097/BRS.0b013e318278e571 · 2.45 Impact Factor
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    The Spine Journal 09/2012; 12(9):S32. DOI:10.1016/j.spinee.2012.08.104 · 2.80 Impact Factor
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    ABSTRACT: : Surgery has been shown to be of benefit for both lumbar stenosis and degenerative spondylolisthesis. For both conditions, surgery often consists of laminectomy with or without fusion. Potential differences in outcomes of these overlapping procedures across various surgical centers have not yet been investigated. : Spine Patient Outcomes Research Trial cohort participants with spinal stenosis (SPS) or degenerative spondylolisthesis (DS) undergoing first-time open lumbar laminectomy with or without fusion were followed from baseline at 6 weeks, and 3, 6 and 12 months, and yearly thereafter, at 13 spine clinics in 11 US states. Mean (SD) follow-up was 45.2 (13.8) months. Median (range) follow-up was 47.4 (1.2, 95.6) months. Baseline characteristics, perioperative events and short- and long-term outcomes were analyzed across the centers. : 793 patients underwent surgery. Significant differences were found across centers in operative duration and blood loss, incidence of durotomy, length of hospital stay, and wound infection. There were no significant differences between centers in incidence of nerve root injury or post-operative mortality. Significant differences were seen in the adjusted change in all indices of functional outcome (SF-36 BP and PF, and Oswestry disability index) at 1 year after surgery and in cumulative adjusted change in ODI score at 4 years. : There is broad and statistically significant variation in outcomes after surgery for SPS and DS across various academic centers, when baseline differences are adjusted for. The findings suggest choice of center affects outcome after these procedures, although further studies are required to investigate which center characteristics are most important.
    Neurosurgery 08/2012; 71(2):E545. DOI:10.1227/01.neu.0000417695.66305.1e · 3.03 Impact Factor
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    ABSTRACT: : Lumbar discectomy is the most commonly performed spine procedure. Academic spine centers with potentially differing caseloads and experience may have different outcomes. : To determine whether the choice of center in which surgery is performed affects lumbar discectomy outcomes. : Spine Patient Outcomes Research Trial participants with a confirmed diagnosis of intervertebral disc herniation undergoing standard first-time open discectomy were followed from baseline at 6 weeks, and 3, 6, and 12 months, and yearly thereafter, at 13 spine clinics in 11 US states. Patient data from this prospective study were reviewed. Enrollment began in March 2000 and ended in November 2004. : Seven hundred ninety-two patients underwent first-time lumbar discectomy. Significant differences were found among centers in patient age and race, baseline levels of disability, and treatment preferences. There were no significant differences among the centers in other patient characteristics (eg, sex, body mass index, the prevalence of smoking, diabetes, or hypertension), or disease characteristics (herniation level or type). Some short-term outcomes varied significantly among centers, including operative duration and blood loss, the incidence of durotomy, the length of hospital stay, and reoperation rate. However, there were no differences among the centers in incidence of nerve root injury, postoperative mortality, Short Form 36 scores of body pain or physical function, or Oswestry Disability Index at 4 years. : Although mean blood loss, risk of durotomy, length of stay, and rate of reoperation vary among academic spine centers performing lumbar discectomy, there appears to be no difference in long-term functional outcomes. : AUC, area under the curveIDH, intervertebral disc herniationSBI, Sciatica Bothersomeness IndexSF-36, Short Form 36SPORT, Spine Patient Outcomes Research Trial.
    Neurosurgery 07/2012; 71(4):833-43. DOI:10.1227/NEU.0b013e31826772cb · 3.03 Impact Factor
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    ABSTRACT: OBJECTIVE: To identify factors that account for variation in complication rates across hospitals and surgeons performing lumbar spinal fusion surgery. DATA SOURCES: Discharge registry including all nonfederal hospitals in Washington State from 2004 to 2007. STUDY DESIGN: We identified adults (n = 6,091) undergoing an initial inpatient lumbar fusion for degenerative conditions. We identified whether each patient had a subsequent complication within 90 days. Logistic regression models with hospital and surgeon random effects were used to examine complications, controlling for patient characteristics and comorbidity. PRINCIPAL FINDINGS: Complications within 90 days of a fusion occurred in 4.8 percent of patients, and 2.2 percent had a reoperation. Hospital effects accounted for 8.8 percent of the total variability, and surgeon effects account for 14.4 percent. Surgeon factors account for 54.5 percent of the variation in hospital reoperation rates, and 47.2 percent of the variation in hospital complication rates. The discretionary use of operative features, such as the inclusion of bone morphogenetic proteins, accounted for 30 and 50 percent of the variation in surgeons' reoperation and complication rates, respectively. CONCLUSIONS: To improve the safety of lumbar spinal fusion surgery, quality improvement efforts that focus on surgeons' discretionary use of operative techniques may be more effective than those that target hospitals.
    Health Services Research 06/2012; 48(1). DOI:10.1111/j.1475-6773.2012.01434.x · 2.49 Impact Factor
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    ABSTRACT: The treatment of craniocervical instability in children is often challenging due to their small spine bones, complex anatomy, and unique syndromes. The authors discuss their surgical experience with 33 cases in the treatment of 31 children (≤ 17 years of age) with craniocervical spine instability using smaller nontraditional titanium screws and plates, as well as intraoperative CT. All craniocervical fusion procedures were performed using intraoperative fluoroscopic imaging and electrophysiological monitoring. Nontraditional spine hardware included smaller screw sizes (2.4 and 2.7 mm) from the orthopedic hand/foot set and mandibular plates. Twenty-three of the 33 surgical procedures were performed with intraoperative CT, which was used to confirm adequate position of the spine hardware and alignment of the spine. The mean patient age was 9.5 years (range 2-17 years). Eleven children underwent a posterior C1-2 transarticular screw fusion, 17 had an occipitocervical fusion, and 3 had a posterior subaxial cervical fusion. The follow-up duration ranged from 9 to 72 months (mean 53 months). All children demonstrated successful fusion at their 3-month follow-up visit, except 1 patient whose unilateral C1-2 transarticular screw fusion required a repeat surgery before proper fusion was achieved. Of the 47 C1-2 transarticular screws that were placed, 13 were 2.4 mm, 15 were 2.7 mm, 7 were 3.5 mm, and 12 were 4.0 mm. Eighteen of the 47 C1-2 transarticular screws were suboptimally placed. Eleven of these misplaced screws were removed and redirected within the same operation because these surgeries benefitted from the use of intraoperative CT; 6 of the 7 remaining suboptimally placed screws were left in place because a second surgery for screw replacement was not warranted. The other suboptimally placed C1-2 screw was replaced during a repeat operation due to failure of fusion. Use of intraoperative CT was invaluable because it enabled the authors to reposition suboptimal C1-2 transarticular screws without necessitating a second operation. Successful craniocervical fusion procedures were achieved using smaller nontraditional titanium screws and plates. Intraoperative CT was a helpful adjunct for confirming and readjusting the trajectory of the screws prior to leaving the operating room, which decreases overall treatment costs and reduces complications.
    Journal of Neurosurgery Pediatrics 06/2012; 9(6):594-601. DOI:10.3171/2012.2.PEDS11329 · 1.37 Impact Factor
  • Sohail K Mirza
    The spine journal: official journal of the North American Spine Society 03/2012; 12(4). DOI:10.1016/j.spinee.2012.03.003 · 2.80 Impact Factor
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    ABSTRACT: Retrospective review of a prospectively collected multi-institutional database. In the present analysis, we investigate the impact of incidental durotomy on outcome in patients undergoing surgery for lumbar degenerative spondylolisthesis. Surgery for lumbar degenerative spondylolisthesis has several potential complications, one of the most common of which is incidental durotomy. The effect of incidental durotomy on outcome, however, remains uncertain. Spine Patient Outcomes Research Trial cohort participants with a confirmed diagnosis of lumbar degenerative spondylolisthesis undergoing standard first-time open decompressive laminectomy, with or without fusion, were followed from baseline at 6 weeks, at 3, 6, 12 months, and yearly thereafter, at 13 spine clinics in 11 US states. Patient data from this prospectively gathered database were reviewed. As of May 2009, the mean (standard deviation [SD]) follow-up among all analyzed degenerative spondylolisthesis patients was 46.6 months (SD = 13.1) (no durotomy: 46.7 vs. had durotomy: 45.2, P = 0.49). The median (range) follow-up time among all analyzed degenerative spondylolisthesis patients was 47.6 months (SD = 2.5-84). A 10.5% incidence of durotomy was detected among the 389 patients undergoing surgery. No significant differences were observed with or without durotomy in age, race, the prevalence of smoking, diabetes and hypertension, decompression level, number of levels, or whether a fusion was performed. There were no differences in incidence of nerve root injury, postoperative mortality, additional surgeries, 36-Item Short Form Health Survey (SF-36) scores of body pain or physical function, or Oswestry Disability Index at 1, 2, 3, and 4 years. Incidental durotomy during first-time surgery for lumbar degenerative spondylolisthesis does not appear to impact outcome in affected patients.
    Spine 03/2012; 37(5):406-13. DOI:10.1097/BRS.0b013e3182349bc5 · 2.45 Impact Factor

Publication Stats

4k Citations
413.61 Total Impact Points

Institutions

  • 2009–2014
    • Dartmouth–Hitchcock Medical Center
      • Department of Surgery
      LEB, New Hampshire, United States
  • 2009–2013
    • Geisel School of Medicine at Dartmouth
      • Department of Orthopaedics
      Hanover, New Hampshire, United States
  • 1997–2013
    • University of Washington Seattle
      • • Department of Orthopaedics and Sports Medicine
      • • Department of Health Services
      • • Department of Medicine
      • • Department of Mechanical Engineering
      Seattle, Washington, United States
  • 2011
    • Dartmouth College
      Hanover, New Hampshire, United States
  • 2007
    • University of California, Davis
      • Department of Family and Community Medicine
      Davis, CA, United States
  • 2002
    • University of Louisville
      • Department of Radiology
      Louisville, KY, United States
  • 1999
    • University of Toronto
      Toronto, Ontario, Canada