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P129. Clinical outcomes following anterior cervical discectomy and fusion for patients with central versus foraminal stenosis
Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S195−S231 Regression with stepwise model selection was employed to explore factors potentially significant in predicting LOS. RESULTS: A total of 718 patients (54.5 years, 41.1%F, 29.1kg/m2). Mean CCI score: 1.11. Within the cohort, 177 patients (24.7%) had a diagnosis of myelopathy, 383 (53.3%) radiculopathy, and 22% with a diagnosis of myeloradiculopathy. Patients with M primary diagnosis were significantly older (62.2 vs 49.8yrs, p<0.001) and had a greater CCI score (1.64 vs 0.82, p<0.001) when compared to R patients. By approach: 76.7% anterior (57.6% of M, 90.6%R, 64.6%MR; p<0.001), 16.4% (35%M, 6%R, 20.9%MR; p<0.001) posterior, 6.5% (6.8%M, 3.4%R, 13.9%MR; p<0.001) combined. Average LOS: M(3.8days), R(1.5 days), MR(2.9 days) p<0.001. LOS for anterior approach in each diagnosis was as follows, M: 2.21, R: 1.21, MR: 1.69 days, p<0.001. Meanwhile, posterior approach LOS, M:6.06, R:2.91, MR:5.0, p<0.001; combined approach M: 5.17, R: 6.23, MR: 5.59, P=0.881. A total of 195 patients were categorized as E-LOS (Avg: 5.87 days), 87 M, 43 R, 65 MR. Major surgical approach of E-LOS for M (60.9%) and MR (44.6%) was posterior; whereas R ELOS patients majorly underwent anterior procedures (53.5%). Generalized linear regression modeling found that the following combination of factors predicted E-LOS in R patients (R2=0.736, p=0.003):BMI, durotomy, CCI, anterior and combined approaches, and cardiac complications. An additional model discovered the predictors of E-LOS in M patients (R2= 0.312, p<0.001): age, hypertension, CCI, anterior and combined approaches, intraoperative complications, neuro complications, ileus, and return to OR in 90 days. Lastly, the model for E-LOS in MR patients consisted of (R2 = 0.267, p=0.001): age, durotomy, BL EQ5D, hypertension, posterior and combined approaches and postoperative complications, specifically neuro. CONCLUSIONS: Independent of surgical approach, patients with a primary diagnosis of myelopathy, though older aged and higher comorbidity profile, had consistently longer overall postop LOS when compared to radiculopathy or myeloradiculopathy patients. The heightened risk in myelopathy patients for extended LOS should be considered when determining admission status for patients undergoing cervical spine surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.552
P128. The association of preoperative disc height with radiographic and clinical outcomes following ACDF Bryce Basques, MD, MHS1, Arash Sayari, BS, MD1, Jannat M. Khan, MD2, Philip Louie, MD1, Michael T. Nolte, MD3, Michael N. Iloanya, MD4, Edward J. Goldberg, MD2, Howard S. An, MD5; 1 Rush University Medical Center, Chicago, IL, US; 2 Midwest Orthopaedics at Rush University, Chicago, IL, US; 3 Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, US; 4 Chicago, IL, US; 5 Rush University Medical Center, Department of Orthopedic Surgery, Chicago, IL, US BACKGROUND CONTEXT: Disc space collapse often occurs later in the natural course of cervical degenerative disc disease, and during anterior cervical discectomy and fusion (ACDF), restoration of disc space height and lordosis can assist with decompression and restoration of alignment. It is unclear if the amount of preoperative cervical disc space collapse correlates with outcomes following ACDF. PURPOSE: The aim of the present study was to characterize preoperative disc space height in a sample of ACDF patients and to determine the association with postoperative clinical and radiographic outcomes following ACDF. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Analysis of consecutive patients who underwent a single-level ACDF between 2008-2015 for cervical radiculopathy and/or myelopathy, with more than 6 months of clinical and radiographic followup was conducted. Exclusion criteria were patients under 18 years of age at the time of surgery, previous cervical fusion or concomitant posterior
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cervical surgery, had postoperative follow up less than 6 months, or had an ACDF for cervical spine fracture, tumor, or infection. OUTCOME MEASURES: Preoperative disc height was measured in terms of preoperative anterior vertebral distance (pAVD), mid-vertebral distance (pMVD), and posterior vertebral distance (pPVD). Sagittal parameters were also measured, and included change in C2-C7 lordosis, T1 angle, levels fused, sagittal vertical axis (SVA), fusion mass lordosis, proximal and distal adjacent segment lordosis. Visual Analog Scale (VAS) neck, VAS arm, and Neck Disability Index (NDI) scores were collected at each postoperative clinical visit. The rates of adjacent segment disease, reoperation, fusion, and subsidence (postoperative disc space collapse >2mm) were determined for the study period. METHODS: Radiographs were reviewed preoperatively and immediately postoperatively, and at final follow up along with patient-reported outcomes. Bivariate and multivariate logistic regressions were subsequently used to compare clinical outcomes between disc height. Multivariate analyses controlled for differences in baseline patient characteristics. RESULTS: A total of 120 patients were included. At final follow-up, pAVD was associated with increased lordosis, SVA and proximal lordosis. Additionally, pMVD was associated with increased postoperative SVA (p=0.025), and final SVA (p=0.011). Preoperative PVD was associated with decreased postoperative distal lordosis (p=0.037) and increased final SVA (p=0.032). Notably, greater pAVD was associated with greater final VAS arm scores (p=0.022), greater pMVD was associated with increased final VAS neck (p=0.037) and final VAS arm scores (p=0.040), and greater pPVD was associated with greater final VAS neck (p=0.031) and arm (p=0.023) scores. Greater AVD, MVD, and PVD were all associated with a decreased preoperative to postoperative difference in VAS neck (p-value range 0.034-0.04). CONCLUSIONS: Increased anterior, middle and posterior preoperative disc height were all associated with increased final SVA, among other parameters. Patients with well-maintained preoperative disc heights had greater final VAS neck scores, VAS arm scores, and had less postoperative improvement in VAS neck scores compared to patients with preoperative collapsed discs. These results suggest that patients with preoperative cervical disc space collapse may have superior outcomes compared to patients with maintained cervical disc height, and future studies are needed to further explore these differences. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.553
P129. Clinical outcomes following anterior cervical discectomy and fusion for patients with central versus foraminal stenosis Bryce Basques, MD, MHS1, Michael T. Nolte, MD2, Philip Louie, MD1, Jannat M. Khan, MD3, Arash Sayari, BS, MD1, Edward J. Goldberg, MD3, Howard S. An, MD4; 1 Rush University Medical Center, Chicago, IL, US; 2 Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, US; 3 Midwest Orthopaedics at Rush University, Chicago, IL, US; 4 Rush University Medical Center, Department of Orthopedic Surgery, Chicago, IL, US BACKGROUND CONTEXT: Anterior cervical discectomy and fusion (ACDF) is an effective surgical option for the treatment of cervical stenosis. However, the adequacy of decompression and stabilization for patients with central stenosis versus foraminal stenosis has been debated. Many advocate for the use or addition of a posterior cervical approach to the neural foramen to ensure adequacy of decompression. However, this may be associated with a number of adverse effects, including inadequacy of central or anterior decompression, when indicated, and persistent postoperative neck pain. PURPOSE: The aim of this study was to assess the effectiveness of ACDF alone across a number of postoperative clinical outcome measures for patients with central stenosis, foraminal stenosis or both. STUDY DESIGN/SETTING: Retrospective cohort analysis.
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.
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Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S195−S231
PATIENT SAMPLE: Analysis was conducted of patients who underwent ACDF for cervical radiculopathy or myelopathy between 2008 and 2015 by one of two senior spine surgeons at our institution. Patients were excluded from analysis if they were under 18 years of age, had a previous operation to the cervical spine, or did not meet a minimum of six months follow-up. OUTCOME MEASURES: Preoperative magnetic resonance imaging (MRI) was assessed to determine the location of neural stenosis and compression. Stenosis that occurred medial to the facet or uncovertebral joint in the axial plane was identified as central, whereas stenosis that occurred at, or lateral to, the facet and uncovertebral joints was identified as foraminal. Sagittal measures on plain films were also measured and analyzed, including cervical lordosis, sagittal vertical axis, fusion and T1 angles. Patient reported outcome measures included visual analogue scale (VAS) neck, VAS-arm and neck disability index (NDI). Objective outcome measures included the incidence of adjacent segment disease (ASD), fusion, subsidence and reoperation rate. METHODS: Anteroposterior (AP) and lateral cervical radiographs were obtained during the preoperative, immediate postoperative (2-week postoperative follow-up appointment), and final follow-up period along with patient reported outcomes. Bivariate and multivariate analyses were performed to account for baseline differences in patient factors. RESULTS: In total, 381 patients met our inclusion criteria. Of these, 126 had central stenosis, 96 had foraminal stenosis, and 159 had both. Average length of follow-up was 28.2 (range 6-101) months. The central stenosisonly and foraminal stenosis-only cohorts had a significantly greater percentage of females compared to the cohort with both central and foraminal stenosis (56.35% and 54.74% versus 40.25%, respectively), with no additional baseline differences between groups. There were no significant differences in the amount of change in the sagittal plane from preoperative to postoperative between cohorts on multivariate analysis. Each cohort experienced considerable improvements in patient reported outcome measures, however, there were no significant differences in preoperative or postoperative VAS-neck, VAS-arm, or NDI scores between groups. Similarly, there were no significant differences in the incidence of ASD, fusion, subsidence, or reoperation rate between groups. CONCLUSIONS: Our findings suggest that ACDF offers adequate decompression and stabilization for patients with cervical stenosis, regardless of the location of neural compression as central, foraminal or a combination of both. These data may help to better guide preoperative planning and consideration of surgical approach to the affected level(s). FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.554
P130. Intraoperative neuromonitoring findings are predictive of neurological outcomes after decompression for cervical spondylotic myelopathy Rouzbeh Motiei-Langroudi, MD1, Ben G. McGahan, MD2, Amy J. Minnema, MS3, Erin Sheehan3, H. Francis Farhadi, MD, PhD, FRCSC2; 1 Beth Israel Deaconess Medical Center, Boston, MA, US; 2 Ohio State Medical Center, Columbus, OH, US; 3 Columbus, OH, US BACKGROUND CONTEXT: Intraoperative Neuromonitoring (IONM) is frequently used by spine surgeons to predict emerging neurological insult and to provide functional feedback prior to development of irreversible neural injury. Despite its widespread use, however, it remains unclear whether various IONM changes are predictive of neurological outcomes in patients who undergo decompression surgery for cervical spondylosis with myelopathy (CSM). PURPOSE: To evaluate the prognosticative ability of IONM changes for neurological outcomes after surgical decompression in patients with CSM. STUDY DESIGN/SETTING: Retrospective evaluation of a prospectively enrolled cohort of patients who underwent surgery for CSM at the Ohio State University Wexner Medical Center.
PATIENT SAMPLE: A total of 39 patients were prospectively enrolled in a CSM trial at our institution and underwent decompression surgery between 2013-17. All patients with available intraoperative somatosensory evoked potential (iSSEP), motor evoked potential (iMEP), and spontaneous electromyography (iEMG) recordings as well as perioperative mJOA scores were included in the study. OUTCOME MEASURES: The modified Japanese Orthopaedic Association (mJOA) scale evaluated at 1-year following surgery. METHODS: Either univariate ANOVA with post hoc analysis (Student −Newman−Keuls) or t-tests were used to analyze DmJOA in relation to iSSEP, iMEP, and iEMG changes. RESULTS: During surgery, iMEPs either improved, remained stable, or decreased in 5, 29 and 5 patients, respectively. iSSEPs improved, remained stable, or decreased in 1, 37 and 1 patient, respectively. Twenty-five patients showed spontaneous iEMG activity, which ultimately resolved in all cases. In patients in whom iMEP decreased, remained stable, or improved, mJOA improved by 1.3, 2.0, and 2.8 points 12 months after surgery, respectively. In contrast to iSSEP (p=0.58), iMEP changes and the presence/absence of iEMG activity during surgery were predictive of DmJOA at 12 months (p=0.02 and 0.007, respectively). CONCLUSIONS: Decompressive surgery for CSM is generally associated with positive neurologic outcomes. Our findings suggest that patients in whom iMEPs improve potentially benefit the most, whilst those with iMEP decreases or spontaneous iEMG activity benefit the least. Whether IONM findings can prognosticate the degree of functional recovery after decompressive surgery for CSM will need to be confirmed in larger scale studies. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.555
P131. Outpatient single-level posterior cervical foraminotomy is associated with lower risk of perioperative complications Mohamed K. Mesregah, MD1, Blake G. Formanek, BA2, Zorica Buser, PhD1, Jeffrey C. Wang, MD3; 1 Keck School of Medicine, University of Southern California, Los Angeles, CA, US; 2 Los Angeles, CA, US; 3 USC Spine Center, Los Angeles, CA, US BACKGROUND CONTEXT: Cervical radiculopathy refers to irritation of nerve roots exiting the cervical spine due to degenerative changes of the facet joints or intervertebral discs. Surgical management may include an anterior or posterior approach. Posterior decompression has been favored due to avoidance of anterior neck structure injury, adjacent segment disease and graft subsidence. Since posterior cervical foraminotomy (PCF) is a relatively safe procedure compared to anterior cervical discectomy and fusion, PCF has gained interest in an outpatient setting. PURPOSE: To compare the perioperative surgical and medical complications associated with inpatient and outpatient single-level PCF. STUDY DESIGN/SETTING: Retrospective database. PATIENT SAMPLE: Patients with cervical radiculopathy who had undergone inpatient or outpatient single-level PCF between 2007 to the first quarter of 2016. OUTCOME MEASURES: Charlson Comorbidity Index (CCI) was used as a broad measure of comorbidity. Surgical complications included cervical nerve root injury, dural tear, wound complications, infection, dysphagia, cervicalgia, CSF leakage and revision surgery. Medical complications included pulmonary embolism and lower limb deep vein thrombosis, acute myocardial infarction, acute respiratory failure, pneumonia, sepsis and urinary complications. METHODS: The Humana subset of the PearlDiver Patient Record Database was queried to identify patients who had undergone inpatient or outpatient single-level PCF using CPT codes. The incidence of perioperative medical and surgical complications was queried for by using relevant ICD9, ICD-10 and CPT codes. CCI was compared between the two groups using the 2-tailed Student-t test. Multivariate logistic regression analysis,
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.
P128. The association of preoperative disc height with radiographic and clinical outcomes following ACDF Bryce Basques, MD, MHS1, Arash Sayari, BS, MD1, Jannat M. Khan, MD2, Philip Louie, MD1, Michael T. Nolte, MD3, Michael N. Iloanya, MD4, Edward J. Goldberg, MD2, Howard S. An, MD5; 1 Rush University Medical Center, Chicago, IL, US; 2 Midwest Orthopaedics at Rush University, Chicago, IL, US; 3 Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, US; 4 Chicago, IL, US; 5 Rush University Medical Center, Department of Orthopedic Surgery, Chicago, IL, US BACKGROUND CONTEXT: Disc space collapse often occurs later in the natural course of cervical degenerative disc disease, and during anterior cervical discectomy and fusion (ACDF), restoration of disc space height and lordosis can assist with decompression and restoration of alignment. It is unclear if the amount of preoperative cervical disc space collapse correlates with outcomes following ACDF. PURPOSE: The aim of the present study was to characterize preoperative disc space height in a sample of ACDF patients and to determine the association with postoperative clinical and radiographic outcomes following ACDF. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Analysis of consecutive patients who underwent a single-level ACDF between 2008-2015 for cervical radiculopathy and/or myelopathy, with more than 6 months of clinical and radiographic followup was conducted. Exclusion criteria were patients under 18 years of age at the time of surgery, previous cervical fusion or concomitant posterior
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cervical surgery, had postoperative follow up less than 6 months, or had an ACDF for cervical spine fracture, tumor, or infection. OUTCOME MEASURES: Preoperative disc height was measured in terms of preoperative anterior vertebral distance (pAVD), mid-vertebral distance (pMVD), and posterior vertebral distance (pPVD). Sagittal parameters were also measured, and included change in C2-C7 lordosis, T1 angle, levels fused, sagittal vertical axis (SVA), fusion mass lordosis, proximal and distal adjacent segment lordosis. Visual Analog Scale (VAS) neck, VAS arm, and Neck Disability Index (NDI) scores were collected at each postoperative clinical visit. The rates of adjacent segment disease, reoperation, fusion, and subsidence (postoperative disc space collapse >2mm) were determined for the study period. METHODS: Radiographs were reviewed preoperatively and immediately postoperatively, and at final follow up along with patient-reported outcomes. Bivariate and multivariate logistic regressions were subsequently used to compare clinical outcomes between disc height. Multivariate analyses controlled for differences in baseline patient characteristics. RESULTS: A total of 120 patients were included. At final follow-up, pAVD was associated with increased lordosis, SVA and proximal lordosis. Additionally, pMVD was associated with increased postoperative SVA (p=0.025), and final SVA (p=0.011). Preoperative PVD was associated with decreased postoperative distal lordosis (p=0.037) and increased final SVA (p=0.032). Notably, greater pAVD was associated with greater final VAS arm scores (p=0.022), greater pMVD was associated with increased final VAS neck (p=0.037) and final VAS arm scores (p=0.040), and greater pPVD was associated with greater final VAS neck (p=0.031) and arm (p=0.023) scores. Greater AVD, MVD, and PVD were all associated with a decreased preoperative to postoperative difference in VAS neck (p-value range 0.034-0.04). CONCLUSIONS: Increased anterior, middle and posterior preoperative disc height were all associated with increased final SVA, among other parameters. Patients with well-maintained preoperative disc heights had greater final VAS neck scores, VAS arm scores, and had less postoperative improvement in VAS neck scores compared to patients with preoperative collapsed discs. These results suggest that patients with preoperative cervical disc space collapse may have superior outcomes compared to patients with maintained cervical disc height, and future studies are needed to further explore these differences. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.553
P129. Clinical outcomes following anterior cervical discectomy and fusion for patients with central versus foraminal stenosis Bryce Basques, MD, MHS1, Michael T. Nolte, MD2, Philip Louie, MD1, Jannat M. Khan, MD3, Arash Sayari, BS, MD1, Edward J. Goldberg, MD3, Howard S. An, MD4; 1 Rush University Medical Center, Chicago, IL, US; 2 Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, US; 3 Midwest Orthopaedics at Rush University, Chicago, IL, US; 4 Rush University Medical Center, Department of Orthopedic Surgery, Chicago, IL, US BACKGROUND CONTEXT: Anterior cervical discectomy and fusion (ACDF) is an effective surgical option for the treatment of cervical stenosis. However, the adequacy of decompression and stabilization for patients with central stenosis versus foraminal stenosis has been debated. Many advocate for the use or addition of a posterior cervical approach to the neural foramen to ensure adequacy of decompression. However, this may be associated with a number of adverse effects, including inadequacy of central or anterior decompression, when indicated, and persistent postoperative neck pain. PURPOSE: The aim of this study was to assess the effectiveness of ACDF alone across a number of postoperative clinical outcome measures for patients with central stenosis, foraminal stenosis or both. STUDY DESIGN/SETTING: Retrospective cohort analysis.
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.
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Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S195−S231
PATIENT SAMPLE: Analysis was conducted of patients who underwent ACDF for cervical radiculopathy or myelopathy between 2008 and 2015 by one of two senior spine surgeons at our institution. Patients were excluded from analysis if they were under 18 years of age, had a previous operation to the cervical spine, or did not meet a minimum of six months follow-up. OUTCOME MEASURES: Preoperative magnetic resonance imaging (MRI) was assessed to determine the location of neural stenosis and compression. Stenosis that occurred medial to the facet or uncovertebral joint in the axial plane was identified as central, whereas stenosis that occurred at, or lateral to, the facet and uncovertebral joints was identified as foraminal. Sagittal measures on plain films were also measured and analyzed, including cervical lordosis, sagittal vertical axis, fusion and T1 angles. Patient reported outcome measures included visual analogue scale (VAS) neck, VAS-arm and neck disability index (NDI). Objective outcome measures included the incidence of adjacent segment disease (ASD), fusion, subsidence and reoperation rate. METHODS: Anteroposterior (AP) and lateral cervical radiographs were obtained during the preoperative, immediate postoperative (2-week postoperative follow-up appointment), and final follow-up period along with patient reported outcomes. Bivariate and multivariate analyses were performed to account for baseline differences in patient factors. RESULTS: In total, 381 patients met our inclusion criteria. Of these, 126 had central stenosis, 96 had foraminal stenosis, and 159 had both. Average length of follow-up was 28.2 (range 6-101) months. The central stenosisonly and foraminal stenosis-only cohorts had a significantly greater percentage of females compared to the cohort with both central and foraminal stenosis (56.35% and 54.74% versus 40.25%, respectively), with no additional baseline differences between groups. There were no significant differences in the amount of change in the sagittal plane from preoperative to postoperative between cohorts on multivariate analysis. Each cohort experienced considerable improvements in patient reported outcome measures, however, there were no significant differences in preoperative or postoperative VAS-neck, VAS-arm, or NDI scores between groups. Similarly, there were no significant differences in the incidence of ASD, fusion, subsidence, or reoperation rate between groups. CONCLUSIONS: Our findings suggest that ACDF offers adequate decompression and stabilization for patients with cervical stenosis, regardless of the location of neural compression as central, foraminal or a combination of both. These data may help to better guide preoperative planning and consideration of surgical approach to the affected level(s). FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.554
P130. Intraoperative neuromonitoring findings are predictive of neurological outcomes after decompression for cervical spondylotic myelopathy Rouzbeh Motiei-Langroudi, MD1, Ben G. McGahan, MD2, Amy J. Minnema, MS3, Erin Sheehan3, H. Francis Farhadi, MD, PhD, FRCSC2; 1 Beth Israel Deaconess Medical Center, Boston, MA, US; 2 Ohio State Medical Center, Columbus, OH, US; 3 Columbus, OH, US BACKGROUND CONTEXT: Intraoperative Neuromonitoring (IONM) is frequently used by spine surgeons to predict emerging neurological insult and to provide functional feedback prior to development of irreversible neural injury. Despite its widespread use, however, it remains unclear whether various IONM changes are predictive of neurological outcomes in patients who undergo decompression surgery for cervical spondylosis with myelopathy (CSM). PURPOSE: To evaluate the prognosticative ability of IONM changes for neurological outcomes after surgical decompression in patients with CSM. STUDY DESIGN/SETTING: Retrospective evaluation of a prospectively enrolled cohort of patients who underwent surgery for CSM at the Ohio State University Wexner Medical Center.
PATIENT SAMPLE: A total of 39 patients were prospectively enrolled in a CSM trial at our institution and underwent decompression surgery between 2013-17. All patients with available intraoperative somatosensory evoked potential (iSSEP), motor evoked potential (iMEP), and spontaneous electromyography (iEMG) recordings as well as perioperative mJOA scores were included in the study. OUTCOME MEASURES: The modified Japanese Orthopaedic Association (mJOA) scale evaluated at 1-year following surgery. METHODS: Either univariate ANOVA with post hoc analysis (Student −Newman−Keuls) or t-tests were used to analyze DmJOA in relation to iSSEP, iMEP, and iEMG changes. RESULTS: During surgery, iMEPs either improved, remained stable, or decreased in 5, 29 and 5 patients, respectively. iSSEPs improved, remained stable, or decreased in 1, 37 and 1 patient, respectively. Twenty-five patients showed spontaneous iEMG activity, which ultimately resolved in all cases. In patients in whom iMEP decreased, remained stable, or improved, mJOA improved by 1.3, 2.0, and 2.8 points 12 months after surgery, respectively. In contrast to iSSEP (p=0.58), iMEP changes and the presence/absence of iEMG activity during surgery were predictive of DmJOA at 12 months (p=0.02 and 0.007, respectively). CONCLUSIONS: Decompressive surgery for CSM is generally associated with positive neurologic outcomes. Our findings suggest that patients in whom iMEPs improve potentially benefit the most, whilst those with iMEP decreases or spontaneous iEMG activity benefit the least. Whether IONM findings can prognosticate the degree of functional recovery after decompressive surgery for CSM will need to be confirmed in larger scale studies. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.555
P131. Outpatient single-level posterior cervical foraminotomy is associated with lower risk of perioperative complications Mohamed K. Mesregah, MD1, Blake G. Formanek, BA2, Zorica Buser, PhD1, Jeffrey C. Wang, MD3; 1 Keck School of Medicine, University of Southern California, Los Angeles, CA, US; 2 Los Angeles, CA, US; 3 USC Spine Center, Los Angeles, CA, US BACKGROUND CONTEXT: Cervical radiculopathy refers to irritation of nerve roots exiting the cervical spine due to degenerative changes of the facet joints or intervertebral discs. Surgical management may include an anterior or posterior approach. Posterior decompression has been favored due to avoidance of anterior neck structure injury, adjacent segment disease and graft subsidence. Since posterior cervical foraminotomy (PCF) is a relatively safe procedure compared to anterior cervical discectomy and fusion, PCF has gained interest in an outpatient setting. PURPOSE: To compare the perioperative surgical and medical complications associated with inpatient and outpatient single-level PCF. STUDY DESIGN/SETTING: Retrospective database. PATIENT SAMPLE: Patients with cervical radiculopathy who had undergone inpatient or outpatient single-level PCF between 2007 to the first quarter of 2016. OUTCOME MEASURES: Charlson Comorbidity Index (CCI) was used as a broad measure of comorbidity. Surgical complications included cervical nerve root injury, dural tear, wound complications, infection, dysphagia, cervicalgia, CSF leakage and revision surgery. Medical complications included pulmonary embolism and lower limb deep vein thrombosis, acute myocardial infarction, acute respiratory failure, pneumonia, sepsis and urinary complications. METHODS: The Humana subset of the PearlDiver Patient Record Database was queried to identify patients who had undergone inpatient or outpatient single-level PCF using CPT codes. The incidence of perioperative medical and surgical complications was queried for by using relevant ICD9, ICD-10 and CPT codes. CCI was compared between the two groups using the 2-tailed Student-t test. Multivariate logistic regression analysis,
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.