Browsing by Author "Riew, K Daniel"

Now showing 1 - 18 of 18
  • Thumbnail Image
    ItemOpen Access
    A Multicenter Review of Superior Laryngeal Nerve Injury Following Anterior Cervical Spine Surgery.
    (Global spine journal, 2017-04) Tempel, Zachary J; Smith, Justin S; Shaffrey, Christopher; Arnold, Paul M; Fehlings, Michael G; Mroz, Thomas E; Riew, K Daniel; Kanter, Adam S
    A retrospective multicenter case-series study; case report and review of the literature.The anatomy and function of the superior laryngeal nerve (SLN) are well described; however, the consequences of SLN injury remain variable and poorly defined. The prevalence of SLN injury as a consequence of cervical spine surgery is difficult to discern as its clinical manifestations are often inconstant and frequently of a subclinical degree. A multicenter study was performed to better delineate the risk factors, prevalence, and outcomes of SLN injury.A retrospective multicenter case-series study involving 21 high-volume surgical centers from the AO Spine North America Clinical Research Network. Medical records for 17 625 patients who received subaxial cervical spine surgery from 2005 to 2011 were reviewed to identify occurrence of 21 predefined treatment complications. Descriptive statistics were provided for baseline patient characteristics. A retrospective review of the neurosurgical literature on SLN injury was also performed.A total of 8887 patients who underwent anterior cervical spine surgery at the participating institutions were screened, and 1 case of SLN palsy was identified. The prevalence ranged from 0% to 1.25% across all centers. The patient identified underwent a C4 corpectomy. The SLN injury was identified after the patient demonstrated difficulty swallowing postoperatively. He underwent placement of a percutaneous gastrostomy tube and his SLN palsy resolved by 6 weeks.This multicenter study demonstrates that identification of SLN injury occurs very infrequently. Symptomatic SLN injury is an exceedingly rare complication of anterior cervical spine surgery. The SLN is particularly vulnerable when exposing the more rostral levels of the cervical spine. Careful dissection and retraction of the longus coli may decrease the risk of SLN injury during anterior cervical surgery.
  • Thumbnail Image
    ItemOpen Access
    A Multicenter Study of the Presentation, Treatment, and Outcomes of Cervical Dural Tears.
    (Global spine journal, 2017-04) O'Neill, Kevin R; Fehlings, Michael G; Mroz, Thomas E; Smith, Zachary A; Hsu, Wellington K; Kanter, Adam S; Steinmetz, Michael P; Arnold, Paul M; Mummaneni, Praveen V; Chou, Dean; Nassr, Ahmad; Qureshi, Sheeraz A; Cho, Samuel K; Baird, Evan O; Smith, Justin S; Shaffrey, Christopher; Tannoury, Chadi A; Tannoury, Tony; Gokaslan, Ziya L; Gum, Jeffrey L; Hart, Robert A; Isaacs, Robert E; Sasso, Rick C; Bumpass, David B; Bydon, Mohamad; Corriveau, Mark; De Giacomo, Anthony F; Derakhshan, Adeeb; Jobse, Bruce C; Lubelski, Daniel; Lee, Sungho; Massicotte, Eric M; Pace, Jonathan R; Smith, Gabriel A; Than, Khoi D; Riew, K Daniel

    Study design

    Retrospective multicenter case series study.

    Objective

    Because cervical dural tears are rare, most surgeons have limited experience with this complication. A multicenter study was performed to better understand the presentation, treatment, and outcomes following cervical dural tears.

    Methods

    Multiple surgeons from 23 institutions retrospectively identified 21 rare complications that occurred between 2005 and 2011, including unintentional cervical dural tears. Demographic data and surgical history were obtained. Clinical outcomes following surgery were assessed, and any reoperations were recorded. Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA), Nurick classification (NuC), and Short-Form 36 (SF36) scores were recorded at baseline and final follow-up at certain centers. All data were collected, collated, and analyzed by a private research organization.

    Results

    There were 109 cases of cervical dural tears among 18 463 surgeries performed. In 101 cases (93%) there was no clinical sequelae following successful dural tear repair. There were statistical improvements (P < .05) in mJOA and NuC scores, but not NDI or SF36 scores. No specific baseline or operative factors were found to be associated with the occurrence of dural tears. In most cases, no further postoperative treatments of the dural tear were required, while there were 13 patients (12%) that required subsequent treatment of cerebrospinal fluid drainage. Analysis of those requiring further treatments did not identify an optimum treatment strategy for cervical dural tears.

    Conclusions

    In this multicenter study, we report our findings on the largest reported series (n = 109) of cervical dural tears. In a vast majority of cases, no subsequent interventions were required and no clinical sequelae were observed.
  • Thumbnail Image
    ItemOpen Access
    Association of myelopathy scores with cervical sagittal balance and normalized spinal cord volume: analysis of 56 preoperative cases from the AOSpine North America Myelopathy study.
    (Spine, 2013-10) Smith, Justin S; Lafage, Virginie; Ryan, Devon J; Shaffrey, Christopher I; Schwab, Frank J; Patel, Alpesh A; Brodke, Darrel S; Arnold, Paul M; Riew, K Daniel; Traynelis, Vincent C; Radcliff, Kris; Vaccaro, Alexander R; Fehlings, Michael G; Ames, Christopher P

    Study design

    Post hoc analysis of prospectively collected data.

    Objective

    Development of methods to determine in vivo spinal cord dimensions and application to correlate preoperative alignment, myelopathy, and health-related quality-of-life scores in patients with cervical spondylotic myelopathy (CSM).

    Summary of background data

    CSM is the leading cause of spinal cord dysfunction. The association between cervical alignment, sagittal balance, and myelopathy has not been well characterized.

    Methods

    This was a post hoc analysis of the prospective, multicenter AOSpine North America CSM study. Inclusion criteria for this study required preoperative cervical magnetic resonance imaging (MRI) and neutral sagittal cervical radiography. Techniques for MRI assessment of spinal cord dimensions were developed. Correlations between imaging and health-related quality-of-life scores were assessed.

    Results

    Fifty-six patients met inclusion criteria (mean age = 55.4 yr). The modified Japanese Orthopedic Association (mJOA) scores correlated with C2-C7 sagittal vertical axis (SVA) (r = -0.282, P = 0.035). Spinal cord volume correlated with cord length (r = 0.472, P < 0.001) and cord average cross-sectional area (r = 0.957, P < 0.001). For all patients, no correlations were found between MRI measurements of spinal cord length, volume, mean cross-sectional area or surface area, and outcomes. For patients with cervical lordosis, mJOA scores correlated positively with cord volume (r = 0.366, P = 0.022), external cord area (r = 0.399, P = 0.012), and mean cross-sectional cord area (r = 0.345, P = 0.031). In contrast, for patients with cervical kyphosis, mJOA scores correlated negatively with cord volume (r = -0.496, P = 0.043) and mean cross-sectional cord area (r = -0.535, P = 0.027).

    Conclusion

    This study is the first to correlate cervical sagittal balance (C2-C7 SVA) to myelopathy severity. We found a moderate negative correlation in kyphotic patients of cord volume and cross-sectional area to mJOA scores. The opposite (positive correlation) was found for lordotic patients, suggesting a relationship of cord volume to myelopathy that differs on the basis of sagittal alignment. It is interesting to note that sagittal balance but not kyphosis is tied to myelopathy score. Future work will correlate alignment changes to cord morphology changes and myelopathy outcomes. SUMMARY STATEMENTS: This is the first study to correlate sagittal balance (C2-C7 SVA) to myelopathy severity. We found a moderate negative correlation in kyphotic patients of cord volume and cross-sectional area to mJOA scores. The opposite (positive correlation) was found for lordotic patients, suggesting a relationship of cord volume to myelopathy that differs on the basis of sagittal alignment.
  • Thumbnail Image
    ItemOpen Access
    Comparison of Best Versus Worst Clinical Outcomes for Adult Cervical Deformity Surgery
    (Global Spine Journal, 2019-05-01) Smith, Justin S; Shaffrey, Christopher I; Kim, Han Jo; Passias, Peter; Protopsaltis, Themistocles; Lafage, Renaud; Mundis, Gregory M; Klineberg, Eric; Lafage, Virginie; Schwab, Frank J; Scheer, Justin K; Kelly, Michael; Hamilton, D Kojo; Gupta, Munish; Deviren, Vedat; Hostin, Richard; Albert, Todd; Riew, K Daniel; Hart, Robert; Burton, Doug; Bess, Shay; Ames, Christopher P
    Study Design: Retrospective cohort study. Objective: Factors that predict outcomes for adult cervical spine deformity (ACSD) have not been well defined. To compare ACSD patients with best versus worst outcomes. Methods: This study was based on a prospective, multicenter observational ACSD cohort. Best versus worst outcomes were compared based on Neck Disability Index (NDI), Neck Pain Numeric Rating Scale (NP-NRS), and modified Japanese Orthopaedic Association (mJOA) scores. Results: Of 111 patients, 80 (72%) had minimum 1-year follow-up. For NDI, compared with best outcome patients (n = 28), worst outcome patients (n = 32) were more likely to have had a major complication (P =.004) and to have undergone a posterior-only procedure (P =.039), had greater Charlson Comorbidity Index (P =.009), and had worse postoperative C7-S1 sagittal vertical axis (SVA; P =.027). For NP-NRS, compared with best outcome patients (n = 26), worst outcome patients (n = 18) were younger (P =.045), had worse baseline NP-NRS (P =.034), and were more likely to have had a minor complication (P =.030). For the mJOA, compared with best outcome patients (n = 16), worst outcome patients (n = 18) were more likely to have had a major complication (P =.007) and to have a better baseline mJOA (P =.030). Multivariate models for NDI included posterior-only surgery (P =.006), major complication (P =.002), and postoperative C7-S1 SVA (P =.012); models for NP-NRS included baseline NP-NRS (P =.009), age (P =.017), and posterior-only surgery (P =.038); and models for mJOA included major complication (P =.008). Conclusions: Factors distinguishing best and worst ACSD surgery outcomes included patient, surgical, and radiographic factors. These findings suggest areas that may warrant greater awareness to optimize patient counseling and outcomes.
  • Thumbnail Image
    ItemOpen Access
    Esophageal Perforation Following Anterior Cervical Spine Surgery: Case Report and Review of the Literature.
    (Global spine journal, 2017-04) Hershman, Stuart H; Kunkle, William A; Kelly, Michael P; Buchowski, Jacob M; Ray, Wilson Z; Bumpass, David B; Gum, Jeffrey L; Peters, Colleen M; Singhatanadgige, Weerasak; Kim, Jin Young; Smith, Zachary A; Hsu, Wellington K; Nassr, Ahmad; Currier, Bradford L; Rahman, Ra'Kerry K; Isaacs, Robert E; Smith, Justin S; Shaffrey, Christopher; Thompson, Sara E; Wang, Jeffrey C; Lord, Elizabeth L; Buser, Zorica; Arnold, Paul M; Fehlings, Michael G; Mroz, Thomas E; Riew, K Daniel
    Multicenter retrospective case series and review of the literature.To determine the rate of esophageal perforations following anterior cervical spine surgery.As part of an AOSpine series on rare complications, a retrospective cohort study was conducted among 21 high-volume surgical centers to identify esophageal perforations following anterior cervical spine surgery. Staff at each center abstracted data from patients' charts and created case report forms for each event identified. Case report forms were then sent to the AOSpine North America Clinical Research Network Methodological Core for data processing and analysis.The records of 9591 patients who underwent anterior cervical spine surgery were reviewed. Two (0.02%) were found to have esophageal perforations following anterior cervical spine surgery. Both cases were detected and treated in the acute postoperative period. One patient was successfully treated with primary repair and debridement. One patient underwent multiple debridement attempts and expired.Esophageal perforation following anterior cervical spine surgery is a relatively rare occurrence. Prompt recognition and treatment of these injuries is critical to minimizing morbidity and mortality.
  • Thumbnail Image
    ItemOpen Access
    Frequency, timing, and predictors of neurological dysfunction in the nonmyelopathic patient with cervical spinal cord compression, canal stenosis, and/or ossification of the posterior longitudinal ligament.
    (Spine, 2013-10) Wilson, Jefferson R; Barry, Sean; Fischer, Dena J; Skelly, Andrea C; Arnold, Paul M; Riew, K Daniel; Shaffrey, Christopher I; Traynelis, Vincent C; Fehlings, Michael G

    Study design

    Systematic review and survey.

    Objective

    To perform an evidence synthesis of the literature and obtain information from the global spine care community assessing the frequency, timing, and predictors of symptom development in patients with radiographical evidence of cervical spinal cord compression, spinal canal narrowing, and/or ossification of posterior longitudinal ligament (OPLL) but no symptoms of myelopathy.

    Summary of background data

    Evidence for a marker to predict symptom development remains sparse, and there is controversy surrounding the management of asymptomatic patients.

    Methods

    We conducted a systematic review of the English language literature and an international survey of spine surgeons to answer the following key questions in patients with radiographical evidence of cervical spinal cord compression, spinal canal narrowing, and/or OPLL but no symptoms of myelopathy: (1) What are the frequency and timing of symptom development? (2) What are the clinical, radiographical, and electrophysiological predictors of symptom development? (3) What clinical and/or radiographical features influence treatment decisions based on an international survey of spine care professionals?

    Results

    The initial literature search yielded 388 citations. Applying the inclusion/exclusion criteria narrowed this to 5 articles. Two of these dealt with the same population. For patients with spinal cord compression secondary to spondylosis, one study reported the frequency of myelopathy development to be 22.6%. The presence of symptomatic radiculopathy, cervical cord hyperintensity on magnetic resonance imaging, and prolonged somatosensory- and motor-evoked potentials were reported in one study as significant independent predictors of myelopathy development. In contrast, the lack of magnetic resonance imaging hyperintensity was found to be a positive predictor of early myelopathy development (≤ 12-mo follow-up). For subjects with OPLL, frequency of myelopathy development was reported in 3 articles and ranged from 0.0% to 61.5% of subjects. One of these studies reported canal stenosis of 60% or more, lateral deviated OPLL, and increased cervical range of motion as significant predictors of myelopathy development. In a survey of 774 spine surgeons, the majority deemed the presence of clinically symptomatic radiculopathy to predict progression to myelopathy in nonmyelopathic patients with cervical stenosis. Survey responses pertaining to 3 patient case vignettes are also presented and discussed in the context of the current literature.

    Conclusion

    On the basis of these results, we provide a series of evidence-based recommendations related to the frequency, timing, and predictors of myelopathy development in asymptomatic patients with cervical stenosis secondary to spondylosis or OPLL. Future prospective studies are required to refine our understanding of this topic. EVIDENCE-BASED CLINICAL RECOMMENDATIONS:

    Recommendation

    Patients with cervical canal stenosis and cord compression secondary to spondylosis, without clinical evidence of myelopathy, and who present with clinical or electrophysiological evidence of cervical radicular dysfunction or central conduction deficits seem to be at higher risk for developing myelopathy and should be counseled to consider surgical treatment.

    Overall strength of evidence

    Moderate.

    Strength of recommendation

    Strong. SUMMARY STATEMENTS: STATEMENT 1: On the basis of the current literature, for patients with cervical canal stenosis and cord compression secondary to spondylosis, without clinical evidence of myelopathy, approximately 8% at 1-year follow-up and 23% at a median of 44-months follow-up develop clinical evidence of myelopathy. STATEMENT 2: For patients with cervical canal stenosis and cord compression secondary to spondylosis, without clinical evidence of myelopathy, the absence of magnetic resonance imaging intramedullary T2 hyperintensity has been shown to predict early myelopathy development (<12-mo follow-up) and the presence of such signal has been shown to predict late myelopathy development (mean 44-mo follow-up). In light of this discrepancy, no definite recommendation can be made surrounding the utility of this finding in predicting myelopathy development. STATEMENT 3: For patients with OPLL but without myelopathy, no recommendation can be made regarding the incidence or predictors of progression to myelopathy.
  • Thumbnail Image
    ItemOpen Access
    Outcomes after laminoplasty compared with laminectomy and fusion in patients with cervical myelopathy: a systematic review.
    (Spine, 2013-10) Yoon, S Tim; Hashimoto, Robin E; Raich, Annie; Shaffrey, Christopher I; Rhee, John M; Riew, K Daniel

    Study design

    Systematic review.

    Objective

    To determine the effectiveness and safety of cervical laminoplasty versus laminectomy and fusion for the treatment of cervical myelopathy, and to identify any patient subgroups for whom one treatment may result in better outcomes than the other.

    Summary of background data

    Cervical laminoplasty and cervical laminectomy plus fusion are both procedures that treat cervical stenosis induced myelopathy by expanding the space available for the spinal cord. Although there are strong proponents of each procedure, the effectiveness, safety, and differential effectiveness and safety of laminoplasty versus laminectomy and fusion remains unclear.

    Methods

    A systematic search of multiple major medical reference databases was conducted to identify studies that compared laminoplasty with laminectomy and fusion. Studies could include either or both cervical myelopathic spondylosis (CSM) and ossification of the posterior longitudinal ligament. Randomized controlled trials and cohort studies were included. Case reports and studies with less than 10 patients in the comparative group were excluded. Japanese Orthopaedic Association, modified Japanese Orthopaedic Association, and Nurick scores were the primary outcomes measuring myelopathy effectiveness. Reoperation and complication rates were evaluated for safety. Clinical recommendations were made through a modified Delphi approach by applying the Grading of Recommendations Assessment, Development and Evaluation/Agency for Healthcare Research and Quality criteria.

    Results

    The search strategy yielded 305 citations, and 4 retrospective cohort studies ultimately met our inclusion criteria. For patients with CSM, data from 3 class of evidence III retrospective cohort studies suggest that there is no difference between treatment groups in severity of myelopathy or pain: 2 studies reported no significant difference between treatment groups in severity of myelopathy, and 3 studies found no significant difference in pain outcomes between treatment groups. For patients with ossification of the posterior longitudinal ligament, one small class of evidence III retrospective cohort study reported significant improvements in myelopathy severity after laminectomy and fusion compared with laminoplasty, but no differences in long-term pain between treatment groups. The overall evidence on the comparative safety of laminoplasty compared with laminectomy and fusion is inconsistent. Reoperation rates were lower after laminoplasty in 2 of 3 studies reporting. However, the incidence of debilitating neck pain was higher after laminoplasty as reported by one study; results on neurological complications were inconclusive, with 2 studies reporting. Results on kyphotic deformity were inconsistent, with opposite results in the 2 studies reporting. After laminectomy and fusion, 1% to 38% of patients had pseudarthrosis. Infection rates were slightly lower after laminoplasty, but the results are not likely to be statistically significant.

    Conclusion

    For patients with CSM, there is low-quality evidence that suggests that laminoplasty and laminectomy and fusion procedures are similarly effective in treating CSM. For patients with ossification of the posterior longitudinal ligament, the evidence regarding the effectiveness of these procedures is insufficient. For both patient populations, the evidence as to whether one procedure is safer than the other is insufficient. Higher-quality research is necessary to more clearly delineate when one procedure is preferred compared with the other. EVIDENCE-BASED CLINICAL RECOMMENDATIONS:

    Recommendation

    For CSM, evidence suggests that laminoplasty and laminectomy-fusion procedures can be similarly effective. We suggest that surgeons consider each case individually and take into account their own familiarity and expertise with each procedure.

    Overall strength of evidence

    Low.

    Strength of recommendation

    Weak.
  • Thumbnail Image
    ItemOpen Access
    Outcomes of Operative Treatment for Adult Cervical Deformity: A Prospective Multicenter Assessment With 1-Year Follow-up.
    (Neurosurgery, 2018-11) Ailon, Tamir; Smith, Justin S; Shaffrey, Christopher I; Kim, Han Jo; Mundis, Gregory; Gupta, Munish; Klineberg, Eric; Schwab, Frank; Lafage, Virginie; Lafage, Renaud; Passias, Peter; Protopsaltis, Themistocles; Neuman, Brian; Daniels, Alan; Scheer, Justin K; Soroceanu, Alex; Hart, Robert; Hostin, Rick; Burton, Douglas; Deviren, Vedat; Albert, Todd J; Riew, K Daniel; Bess, Shay; Ames, Christopher P; International Spine Study Group
    BACKGROUND:Despite the potential for profound impact of adult cervical deformity (ACD) on function and health-related quality of life (HRQOL), there are few high-quality studies that assess outcomes of surgical treatment for these patients. OBJECTIVE:To determine the impact of surgical treatment for ACD on HRQOL. METHODS:We conducted a prospective cohort study of surgically treated ACD patients eligible for 1-yr follow-up. Baseline deformity characteristics, surgical parameters, and 1-yr HRQOL outcomes were assessed. RESULTS:Of 77 ACD patients, 55 (71%) had 1-yr follow-up (64% women, mean age of 62 yr, mean Charlson Comorbidity Index of 0.6, previous cervical surgery in 47%). Diagnoses included cervical sagittal imbalance (56%), cervical kyphosis (55%), proximal junctional kyphosis (7%) and coronal deformity (9%). Posterior fusion was performed in 85% (mean levels = 10), and anterior fusion was performed in 53% (mean levels = 5). Three-column osteotomy was performed in 24% of patients. One year following surgery, ACD patients had significant improvement in Neck Disability Index (50.5 to 38.0, P < .001), neck pain numeric rating scale score (6.9 to 4.3, P < .001), EuroQol 5 dimension (EQ-5D) index (0.51 to 0.66, P < .001), and EQ-5D subscores: mobility (1.9 to 1.7, P = .019), usual activities (2.2 to 1.9, P = .007), pain/discomfort (2.4 to 2.1, P < .001), anxiety/depression (1.8 to 1.5, P = .014). CONCLUSION:Based on a prospective multicenter series of ACD patients, surgical treatment provided significant improvement in multiple measures of pain and function, including Neck Disability Index, neck pain numeric rating scale score, and EQ-5D. Further follow-up will be necessary to assess the long-term durability of these improved outcomes.
  • Thumbnail Image
    ItemOpen Access
    Predictive factors affecting outcome after cervical laminoplasty.
    (Spine, 2013-10) Yoon, S Tim; Raich, Annie; Hashimoto, Robin E; Riew, K Daniel; Shaffrey, Christopher I; Rhee, John M; Tetreault, Lindsay A; Skelly, Andrea C; Fehlings, Michael G

    Study design

    Systematic review.

    Objective

    To determine whether various preoperative factors affect patient outcome after cervical laminoplasty for cervical spondylotic myelopathy (CSM) and/or ossification of posterior longitudinal ligament (OPLL).

    Summary of background data

    Cervical laminoplasty is a procedure designed to decompress the spinal cord by enlarging the spinal canal while preserving the lamina. Prior research has identified a variety of potential predictive factors that might affect outcomes after this procedure.

    Methods

    A systematic search of multiple major medical reference databases was conducted to identify studies explicitly designed to evaluate the effect of preoperative factors on patient outcome after cervical laminoplasty for CSM or OPLL. Studies specifically designed to evaluate potential predictive factors and their associations with outcome were included. Only cohort studies that used multivariate analysis, enrolled at least 20 patients, and adjusted for age as a potential confounding variable were included. JOA (Japanese Orthopaedic Association), modified JOA, and JOACMEQ-L (JOA Cervical Myelopathy Evaluation Questionnaire lower extremity function section) scores were the main outcome measures. Clinical recommendations and consensus statements were made through a modified Delphi approach by applying the GRADE (Grading of Recommendation Assessment, Development and Evaluation)/AHRQ (Agency for Healthcare Research and Quality) criteria.

    Results

    The search strategy yielded 433 citations, of which 1 prospective and 11 retrospective cohort studies met our inclusion criteria. Overall, the strength of evidence from the 12 studies is low or insufficient for most of the predictive factors. Increased age was not associated with poorer JOA outcomes for patients with CSM, but there is insufficient evidence to make a conclusion for patients with OPLL. Increased severity of disease and a longer duration of symptoms might be associated with JOA outcomes for patients with CSM. Hill-shaped lesions might be associated with poorer JOA outcomes for patients with OPLL. There is insufficient evidence to permit conclusions regarding other predictive factors.

    Conclusion

    Overall, the strength of evidence for all of the predictive factors was insufficient or low. Given that cervical myelopathy due to CSM tends to be progressive and that increased severity of myelopathy and duration of symptoms might be associated with poorer outcomes after cervical laminoplasty for CSM, it is preferable to perform laminoplasty in patients with CSM earlier rather than waiting for symptoms to get worse. Further research is needed to more clearly identify predictive factors that affect outcomes after cervical laminoplasty because there were relatively few studies identified that used multivariate analyses to control for confounding factors and many of these studies did not provide a detailed description of the multivariate analyses or the magnitude of effect estimates. EVIDENCE-BASED CLINICAL RECOMMENDATIONS:

    Recommendation 1

    For patients with CSM, increased age is not a strong predictor of clinical neurological outcomes after laminoplasty; therefore, age by itself should not preclude cervical laminoplasty for CSM.

    Overall strength of evidence

    Low.

    Strength of recommendation

    Strong.

    Recommendation 2

    For patients with CSM, increased severity of disease and a longer duration of symptoms might be associated with poorer clinical neurological outcomes after laminoplasty; therefore, we recommend that patients be informed about this.

    Overall strength of evidence

    Low.

    Strength of recommendation

    Strong. SUMMARY STATEMENTS: For patients with OPLL, hill-shaped lesions might be associated with poorer clinical neurological outcomes after laminoplasty; therefore, surgeons might consider potential benefits and risks of alternative or additional surgery.
  • Thumbnail Image
    ItemOpen Access
    Prospective Multicenter Assessment of All-Cause Mortality Following Surgery for Adult Cervical Deformity.
    (Neurosurgery, 2018-12) Smith, Justin S; Shaffrey, Christopher I; Kim, Han Jo; Passias, Peter; Protopsaltis, Themistocles; Lafage, Renaud; Mundis, Gregory M; Klineberg, Eric; Lafage, Virginie; Schwab, Frank J; Scheer, Justin K; Miller, Emily; Kelly, Michael; Hamilton, D Kojo; Gupta, Munish; Deviren, Vedat; Hostin, Richard; Albert, Todd; Riew, K Daniel; Hart, Robert; Burton, Doug; Bess, Shay; Ames, Christopher P; International Spine Study Group
    BACKGROUND:Surgical treatments for adult cervical spinal deformity (ACSD) are often complex and have high complication rates. OBJECTIVE:To assess all-cause mortality following ACSD surgery. METHODS:ACSD patients presenting for surgical treatment were identified from a prospectively collected multicenter database. Clinical and surgical parameters and all-cause mortality were assessed. RESULTS:Of 123 ACSD patients, 120 (98%) had complete baseline data (mean age, 60.6 yr). The mean number of comorbidities per patient was 1.80, and 80% had at least 1 comorbidity. Surgical approaches included anterior only (15.8%), posterior only (50.0%), and combined anterior/posterior (34.2%). The mean number of vertebral levels fused was 8.0 (standard deviation [SD] = 4.5), and 23.3% had a 3-column osteotomy. Death was reported for 11 (9.2%) patients at a mean of 1.1 yr (SD = 0.76 yr; range = 7 d to 2 yr). Mean follow-up for living patients was 1.2 yr (SD = 0.64 yr). Causes of death included myocardial infarction (n = 2), pneumonia/cardiopulmonary failure (n = 2), sepsis (n = 1), obstructive sleep apnea/narcotics (n = 1), subsequently diagnosed amyotrophic lateral sclerosis (n = 1), burn injury related to home supplemental oxygen (n = 1), and unknown (n = 3). Deceased patients did not significantly differ from alive patients based on demographic, clinical, or surgical parameters assessed, except for a higher major complication rate (excluding mortality; 63.6% vs 22.0%, P = .006). CONCLUSION:All-cause mortality at a mean of 1.2 yr following surgery for ACSD was 9.2% in this prospective multicenter series. Causes of death were reflective of the overall high level of comorbidities. These findings may prove useful for treatment decision making and patient counseling in the context of the substantial impact of ACSD.
  • Thumbnail Image
    ItemOpen Access
    Prospective Multicenter Assessment of Early Complication Rates Associated With Adult Cervical Deformity Surgery in 78 Patients.
    (Neurosurgery, 2016-09) Smith, Justin S; Ramchandran, Subaraman; Lafage, Virginie; Shaffrey, Christopher I; Ailon, Tamir; Klineberg, Eric; Protopsaltis, Themistocles; Schwab, Frank J; OʼBrien, Michael; Hostin, Richard; Gupta, Munish; Mundis, Gregory; Hart, Robert; Kim, Han Jo; Passias, Peter G; Scheer, Justin K; Deviren, Vedat; Burton, Douglas C; Eastlack, Robert; Bess, Shay; Albert, Todd J; Riew, K Daniel; Ames, Christopher P; International Spine Study Group

    Background

    Few reports have focused on treatment of adult cervical deformity (ACD).

    Objective

    To present early complication rates associated with ACD surgery.

    Methods

    A prospective multicenter database of consecutive operative ACD patients was reviewed for early (≤30 days from surgery) complications. Enrollment required at least 1 of the following: cervical kyphosis >10 degrees, cervical scoliosis >10 degrees, C2-7 sagittal vertical axis >4 cm, or chin-brow vertical angle >25 degrees.

    Results

    Seventy-eight patients underwent surgical treatment for ACD (mean age, 60.8 years). Surgical approaches included anterior-only (14%), posterior-only (49%), anterior-posterior (35%), and posterior-anterior-posterior (3%). Mean numbers of fused anterior and posterior vertebral levels were 4.7 and 9.4, respectively. A total of 52 early complications were reported, including 26 minor and 26 major. Twenty-two (28.2%) patients had at least 1 minor complication, and 19 (24.4%) had at least 1 major complication. Overall, 34 (43.6%) patients had at least 1 complication. The most common complications included dysphagia (11.5%), deep wound infection (6.4%), new C5 motor deficit (6.4%), and respiratory failure (5.1%). One (1.3%) mortality occurred. Early complication rates differed significantly by surgical approach: anterior-only (27.3%), posterior-only (68.4%), and anterior-posterior/posterior-anterior-posterior (79.3%) (P = .007).

    Conclusion

    This report provides benchmark rates for overall and specific ACD surgery complications. Although the surgical approach(es) used were likely driven by the type and complexity of deformity, there were significantly higher complication rates associated with combined and posterior-only approaches compared with anterior-only approaches. These findings may prove useful in treatment planning, patient counseling, and ongoing efforts to improve safety of care.

    Abbreviations

    3CO, 3-column osteotomiesACD, adult cervical deformityEBL, estimated blood lossISSG, International Spine Study groupSVA, sagittal vertical axis.
  • Thumbnail Image
    ItemOpen Access
    Rare Complications of Cervical Spine Surgery: Horner's Syndrome.
    (Global spine journal, 2017-04) Traynelis, Vincent C; Malone, Hani R; Smith, Zachary A; Hsu, Wellington K; Kanter, Adam S; Qureshi, Sheeraz A; Cho, Samuel K; Baird, Evan O; Isaacs, Robert E; Rahman, Ra'Kerry K; Polevaya, Galina; Smith, Justin S; Shaffrey, Christopher; Tortolani, P Justin; Stroh, D Alex; Arnold, Paul M; Fehlings, Michael G; Mroz, Thomas E; Riew, K Daniel
    A multicenter retrospective case series.Horner's syndrome is a known complication of anterior cervical spinal surgery, but it is rarely encountered in clinical practice. To better understand the incidence, risks, and neurologic outcomes associated with Horner's syndrome, a multicenter study was performed to review a large collective experience with this rare complication.We conducted a retrospective multicenter case series study involving 21 high-volume surgical centers from the AOSpine North America Clinical Research Network. Medical records for 17 625 patients who received subaxial cervical spine surgery from 2005 to 2011 were reviewed to identify occurrence of 21 predefined treatment complications. Descriptive statistics were provided for baseline patient characteristics. Paired t test was used to analyze changes in clinical outcomes at follow-up compared to preoperative status.In total, 8887 patients who underwent anterior cervical spine surgery at the participating institutions were screened. Postoperative Horner's syndrome was identified in 5 (0.06%) patients. All patients experienced the complication following anterior cervical discectomy and fusion. The sympathetic trunk appeared to be more vulnerable when operating on midcervical levels (C5, C6), and most patients experienced at least a partial recovery without further treatment.This collective experience suggests that Horner's syndrome is an exceedingly rare complication following anterior cervical spine surgery. Injury to the sympathetic trunk may be limited by maintaining a midline surgical trajectory when possible, and performing careful dissection and retraction of the longus colli muscle when lateral exposure is necessary, especially at caudal cervical levels.
  • Thumbnail Image
    ItemOpen Access
    Rare Complications of Cervical Spine Surgery: Pseudomeningocoele.
    (Global spine journal, 2017-04) Ailon, Tamir; Smith, Justin S; Nassr, Ahmad; Smith, Zachary A; Hsu, Wellington K; Fehlings, Michael G; Fish, David E; Wang, Jeffrey C; Hilibrand, Alan S; Mummaneni, Praveen V; Chou, Dean; Sasso, Rick C; Traynelis, Vincent C; Arnold, Paul M; Mroz, Thomas E; Buser, Zorica; Lord, Elizabeth L; Massicotte, Eric M; Sebastian, Arjun S; Than, Khoi D; Steinmetz, Michael P; Smith, Gabriel A; Pace, Jonathan; Corriveau, Mark; Lee, Sungho; Riew, K Daniel; Shaffrey, Christopher
    This study was a retrospective, multicenter cohort study.Rare complications of cervical spine surgery are inherently difficult to investigate. Pseudomeningocoele (PMC), an abnormal collection of cerebrospinal fluid that communicates with the subarachnoid space, is one such complication. In order to evaluate and better understand the incidence, presentation, treatment, and outcome of PMC following cervical spine surgery, we conducted a multicenter study to pool our collective experience.This study was a retrospective, multicenter cohort study of patients who underwent cervical spine surgery at any level(s) from C2 to C7, inclusive; were over 18 years of age; and experienced a postoperative PMC.Thirteen patients (0.08%) developed a postoperative PMC, 6 (46.2%) of whom were female. They had an average age of 48.2 years and stayed in hospital a mean of 11.2 days. Three patients were current smokers, 3 previous smokers, 5 had never smoked, and 2 had unknown smoking status. The majority, 10 (76.9%), were associated with posterior surgery, whereas 3 (23.1%) occurred after an anterior procedure. Myelopathy was the most common indication for operations that were complicated by PMC (46%). Seven patients (53%) required a surgical procedure to address the PMC, whereas the remaining 6 were treated conservatively. All PMCs ultimately resolved or were successfully treated with no residual effects.PMC is a rare complication of cervical surgery with an incidence of less than 0.1%. They prolong hospital stay. PMCs occurred more frequently in association with posterior approaches. Approximately half of PMCs required surgery and all ultimately resolved without residual neurologic or other long-term effects.
  • Thumbnail Image
    ItemOpen Access
    Reliability assessment of a novel cervical spine deformity classification system.
    (Journal of neurosurgery. Spine, 2015-12) Ames, Christopher P; Smith, Justin S; Eastlack, Robert; Blaskiewicz, Donald J; Shaffrey, Christopher I; Schwab, Frank; Bess, Shay; Kim, Han Jo; Mundis, Gregory M; Klineberg, Eric; Gupta, Munish; O'Brien, Michael; Hostin, Richard; Scheer, Justin K; Protopsaltis, Themistocles S; Fu, Kai-Ming G; Hart, Robert; Albert, Todd J; Riew, K Daniel; Fehlings, Michael G; Deviren, Vedat; Lafage, Virginie; International Spine Study Group

    Object

    Despite the complexity of cervical spine deformity (CSD) and its significant impact on patient quality of life, there exists no comprehensive classification system. The objective of this study was to develop a novel classification system based on a modified Delphi approach and to characterize the intra- and interobserver reliability of this classification.

    Methods

    Based on an extensive literature review and a modified Delphi approach with an expert panel, a CSD classification system was generated. The classification system included a deformity descriptor and 5 modifiers that incorporated sagittal, regional, and global spinopelvic alignment and neurological status. The descriptors included: "C," "CT," and "T" for primary cervical kyphotic deformities with an apex in the cervical spine, cervicothoracic junction, or thoracic spine, respectively; "S" for primary coronal deformity with a coronal Cobb angle ≥ 15°; and "CVJ" for primary craniovertebral junction deformity. The modifiers included C2-7 sagittal vertical axis (SVA), horizontal gaze (chin-brow to vertical angle [CBVA]), T1 slope (TS) minus C2-7 lordosis (TS-CL), myelopathy (modified Japanese Orthopaedic Association [mJOA] scale score), and the Scoliosis Research Society (SRS)-Schwab classification for thoracolumbar deformity. Application of the classification system requires the following: 1) full-length standing posteroanterior (PA) and lateral spine radiographs that include the cervical spine and femoral heads; 2) standing PA and lateral cervical spine radiographs; 3) completed and scored mJOA questionnaire; and 4) a clinical photograph or radiograph that includes the skull for measurement of the CBVA. A series of 10 CSD cases, broadly representative of the classification system, were selected and sufficient radiographic and clinical history to enable classification were assembled. A panel of spinal deformity surgeons was queried to classify each case twice, with a minimum of 1 intervening week. Inter- and intrarater reliability measures were based on calculations of Fleiss k coefficient values.

    Results

    Twenty spinal deformity surgeons participated in this study. Interrater reliability (Fleiss k coefficients) for the deformity descriptor rounds 1 and 2 were 0.489 and 0.280, respectively, and mean intrarater reliability was 0.584. For the modifiers, including the SRS-Schwab components, the interrater (round 1/round 2) and intrarater reliabilities (Fleiss k coefficients) were: C2-7 SVA (0.338/0.412, 0.584), horizontal gaze (0.779/0.430, 0.768), TS-CL (0.721/0.567, 0.720), myelopathy (0.602/0.477, 0.746), SRS-Schwab curve type (0.590/0.433, 0.564), pelvic incidence-lumbar lordosis (0.554/0.386, 0.826), pelvic tilt (0.714/0.627, 0.633), and C7-S1 SVA (0.071/0.064, 0.233), respectively. The parameter with the poorest reliability was the C7-S1 SVA, which may have resulted from differences in interpretation of positive and negative measurements.

    Conclusions

    The proposed classification provides a mechanism to assess CSD within the framework of global spinopelvic malalignment and clinically relevant parameters. The intra- and interobserver reliabilities suggest moderate agreement and serve as the basis for subsequent improvement and study of the proposed classification.
  • Thumbnail Image
    ItemOpen Access
    Riluzole for Degenerative Cervical Myelopathy: A Secondary Analysis of the CSM-PROTECT Trial.
    (JAMA network open, 2024-06) Fehlings, Michael G; Pedro, Karlo M; Alvi, Mohammed Ali; Badhiwala, Jetan H; Ahn, Henry; Farhadi, H Francis; Shaffrey, Christopher I; Nassr, Ahmad; Mummaneni, Praveen; Arnold, Paul M; Jacobs, W Bradley; Riew, K Daniel; Kelly, Michael; Brodke, Darrel S; Vaccaro, Alexander R; Hilibrand, Alan S; Wilson, Jason; Harrop, James S; Yoon, S Tim; Kim, Kee D; Fourney, Daryl R; Santaguida, Carlo; Massicotte, Eric M; Huang, Peng

    Importance

    The modified Japanese Orthopaedic Association (mJOA) scale is the most common scale used to represent outcomes of degenerative cervical myelopathy (DCM); however, it lacks consideration for neck pain scores and neglects the multidimensional aspect of recovery after surgery.

    Objective

    To use a global statistical approach that incorporates assessments of multiple outcomes to reassess the efficacy of riluzole in patients undergoing spinal surgery for DCM.

    Design, setting, and participants

    This was a secondary analysis of prespecified secondary end points within the Efficacy of Riluzole in Surgical Treatment for Cervical Spondylotic Myelopathy (CSM-PROTECT) trial, a multicenter, double-blind, phase 3 randomized clinical trial conducted from January 2012 to May 2017. Adult surgical patients with DCM with moderate to severe myelopathy (mJOA scale score of 8-14) were randomized to receive either riluzole or placebo. The present study was conducted from July to December 2023.

    Intervention

    Riluzole (50 mg twice daily) or placebo for a total of 6 weeks, including 2 weeks prior to surgery and 4 weeks following surgery.

    Main outcomes and measures

    The primary outcome measure was a difference in clinical improvement from baseline to 1-year follow-up, assessed using a global statistical test (GST). The 36-Item Short Form Health Survey Physical Component Score (SF-36 PCS), arm and neck pain numeric rating scale (NRS) scores, American Spinal Injury Association (ASIA) motor score, and Nurick grade were combined into a single summary statistic known as the global treatment effect (GTE).

    Results

    Overall, 290 patients (riluzole group, 141; placebo group, 149; mean [SD] age, 59 [10.1] years; 161 [56%] male) were included. Riluzole showed a significantly higher probability of global improvement compared with placebo at 1-year follow-up (GTE, 0.08; 95% CI, 0.00-0.16; P = .02). A similar favorable global response was seen at 35 days and 6 months (GTE for both, 0.07; 95% CI, -0.01 to 0.15; P = .04), although the results were not statistically significant. Riluzole-treated patients had at least a 54% likelihood of achieving better outcomes at 1 year compared with the placebo group. The ASIA motor score and neck and arm pain NRS combination at 1 year provided the best-fit parsimonious model for detecting a benefit of riluzole (GTE, 0.11; 95% CI, 0.02-0.16; P = .007).

    Conclusions and relevance

    In this secondary analysis of the CSM-PROTECT trial using a global outcome technique, riluzole was associated with improved clinical outcomes in patients with DCM. The GST offered probability-based results capable of representing diverse outcome scales and should be considered in future studies assessing spine surgery outcomes.
  • Thumbnail Image
    ItemOpen Access
    Safety and efficacy of riluzole in patients undergoing decompressive surgery for degenerative cervical myelopathy (CSM-Protect): a multicentre, double-blind, placebo-controlled, randomised, phase 3 trial.
    (The Lancet. Neurology, 2021-02) Fehlings, Michael G; Badhiwala, Jetan H; Ahn, Henry; Farhadi, H Francis; Shaffrey, Christopher I; Nassr, Ahmad; Mummaneni, Praveen; Arnold, Paul M; Jacobs, W Bradley; Riew, K Daniel; Kelly, Michael; Brodke, Darrel S; Vaccaro, Alexander R; Hilibrand, Alan S; Wilson, Jason; Harrop, James S; Yoon, S Tim; Kim, Kee D; Fourney, Daryl R; Santaguida, Carlo; Massicotte, Eric M; Kopjar, Branko

    Background

    Degenerative cervical myelopathy represents the most common form of non-traumatic spinal cord injury. This trial investigated whether riluzole enhances outcomes in patients undergoing decompression surgery for degenerative cervical myelopathy.

    Methods

    This multicentre, double-blind, placebo-controlled, randomised, phase 3 trial was done at 16 university-affiliated centres in Canada and the USA. Patients with moderate-to-severe degenerative cervical myelopathy aged 18-80 years, who had a modified Japanese Orthopaedic Association (mJOA) score of 8-14, were eligible. Patients were randomly assigned (1:1) to receive either oral riluzole (50 mg twice a day for 14 days before surgery and then for 28 days after surgery) or placebo. Randomisation was done using permuted blocks stratified by study site. Patients, physicians, and outcome assessors remained masked to treatment group allocation. The primary endpoint was change in mJOA score from baseline to 6 months in the intention-to-treat (ITT) population, defined as all individuals who underwent randomisation and surgical decompression. Adverse events were analysed in the modified intention-to-treat (mITT) population, defined as all patients who underwent randomisation, including those who did not ultimately undergo surgical decompression. This study is registered with ClinicalTrials.gov, NCT01257828.

    Findings

    From Jan 31, 2012, to May 16, 2017, 408 patients were screened. Of those screened, 300 were eligible (mITT population); 290 patients underwent decompression surgery (ITT population) and received either riluzole (n=141) or placebo (n=149). There was no difference between the riluzole and placebo groups in the primary endpoint of change in mJOA score at 6-month follow-up: 2·45 points (95% CI 2·08 to 2·82 points) versus 2·83 points (2·47 to 3·19), difference -0·38 points (-0·90 to 0·13; p=0·14). The most common adverse events were neck or arm or shoulder pain, arm paraesthesia, dysphagia, and worsening of myelopathy. There were 43 serious adverse events in 33 (22%) of 147 patients in the riluzole group and 34 serious adverse events in 29 (19%) of 153 patients in the placebo group. The most frequent severe adverse events were osteoarthrosis of non-spinal joints, worsening of myelopathy, and wound complications.

    Interpretation

    In this trial, adjuvant treatment for 6 weeks perioperatively with riluzole did not improve functional recovery beyond decompressive surgery in patients with moderate-to-severe degenerative cervical myelopathy. Whether riluzole has other benefits in this patient population merits further study.

    Funding

    AOSpine North America.
  • Thumbnail Image
    ItemOpen Access
    Terminology.
    (Spine, 2012-10) Anderson, Paul A; Andersson, Gunnar BJ; Arnold, Paul M; Brodke, Darrel S; Brodt, Erika D; Chapman, Jens R; Chou, Dean; Dekutoski, Mark; Dettori, Joseph R; DeVine, John G; Ely, Claire G; Fehlings, Michael G; Fischer, Dena J; Fourney, Daryl R; Hansen, Mitchell A; Harrod, Christopher Chambliss; Hashimoto, Robin; Hermsmeyer, Jeffrey T; Hilibrand, Alan S; Kasliwal, Manish K; Kelly, Michael P; Kim, Han Jo; Kraemer, Paul; Lawrence, Brandon D; Lee, Michael J; Lenke, Lawrence G; Norvell, Daniel C; Raich, Annie; Riew, K Daniel; Shaffrey, Christopher I; Skelly, Andrea C; Smith, Justin S; Standaert, Christopher J; Van Alstyne, Ellen M; Wang, Jeffrey C
  • Thumbnail Image
    ItemOpen Access
    The health impact of adult cervical deformity in patients presenting for surgical treatment: Comparison to United States population norms and chronic disease states based on the EuroQuol-5 dimensions questionnaire
    (Clinical Neurosurgery, 2017-05-01) Smith, Justin S; Line, Breton; Bess, Shay; Shaffrey, Christopher I; Kim, Han Jo; Mundis, Gregory; Scheer, Justin K; Klineberg, Eric; O'Brien, Michael; Hostin, Richard; Gupta, Munish; Daniels, Alan; Kelly, Michael; Gum, Jeffrey L; Schwab, Frank J; Lafage, Virginie; Lafage, Renaud; Ailon, Tamir; Passias, Peter; Protopsaltis, Themistocles; Albert, Todd J; Riew, K Daniel; Hart, Robert; Burton, Doug; Deviren, Vedat; Ames, Christopher P; Group, International Spine Study
    BACKGROUND: Although adult cervical spine deformity (ACSD) is associated with pain and disability, its health impact has not been quantified in comparison to other chronic diseases. OBJECTIVE: To perform a comparative analysis of the health impact of symptomatic ACSD to US normative and chronic disease values using EQ-5D (EuroQuol-5 Dimensions questionnaire) scores. METHODS: ACSD patients presenting for surgical treatment were identified from a prospectively collected multicenter database. Baseline demographics and EQ-5D scores were collected and compared with US normative and disease state values. RESULTS: Of 121 ACSD patients, 115 (95%) completed the EQ-5D (60% women, mean age 61 years, previous spine surgery in 44%). Diagnoses included kyphosis with mid-cervical (63.4%), cervico-thoracic (23.5%), or thoracic (8.7%) apex and primary coronal deformity (4.3%). The mean ACSD EQ-5D index was 0.511 (standard definition = 0.224), which is 34% below the bottom 25th percentile (0.780) for similar age- and gender-matched US normative populations. Mean ACSD EQ-5D index values were worse than the bottom 25th percentile for several other disease states, including chronic ischemic heart disease (0.708), malignant breast cancer (0.708), and malignant prostate cancer (0.708). ACSD mean index values were comparable to the bottom 25th percentile values for blindness/low vision (0.543), emphysema (0.508), renal failure (0.506), and stroke (0.463). EQ-5D scores did not significantly differ based on cervical deformity type (P =.66). CONCLUSION: The health impact of symptomatic ACSD is substantial, with negative impact across all EQ-5D domains. The mean ACSD EQ-5D index was comparable to the bottom 25th percentile values for blindness/low vision, emphysema, renal failure, and stroke.