Faculty Bibliography

BACKGROUND CONTEXT: Cervical deformity (CD) severity has been linked to poor quality of life and severe neck pain. However, little is known of the relationship between surgical invasiveness accounting for cervical deformity severity and frailty status. PURPOSE: Investigate the outcomes of CD surgery by invasiveness, frailty status and baseline degree of deformity. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Ninety-six CD patients. OUTCOME MEASURES: HRQL measurements: NDI, EQ5D, mJOA.
METHOD(S): Inclusion criteria was defined as operative CD patients (C2-C7 Cobb>10degreeor CK>10degree, cSVA>4cm or CBVA>25degree) >18yr with follow up (1-year) radiographic and HRQL scores, NDI, mJOA and EQ5D. Patients were stratified by severity of deformity by TS-CL, categorized by the new-mJOA based modifiers: Low/Mod <45degree (Low-Mod); Severe >45degree(Sev). Frailty scores were calculated based upon the modified CD frailty index by Passias et. Al and categorized into severely frail (SF) >=0.5 and not SF (N-SF)<0.5. Patients were categorized by their frailty and deformity status (Low-Mod/N-SF; Low-Mod/SF; Sev/N-SF; Sev/SF). Logistic regression analysis assessed the relationship between increasing invasiveness and outcomes (DJK, complications). Within the significant frailty/deformity risk groups, decision tree analysis assessed thresholds for an invasiveness severity cut-off point, below which experiencing a reoperation, complication, DJK occurrence and poor mJOA were higher.
RESULT(S): Ninety-six CD patients met inclusion criteria (62.2+/-10.2 years, 66% female, 28.4+/-7.4 kg/m2). By approach: 19.8% anterior-only, 47.9% posterior-only, 32.3% combined (levels fused: 7.7+/-3.9). By deformity severity: 23.7% Low, 40.9% Moderate, 34.4% Severe, while frailty assessment placed 32.3% in N-SF and 67.7% SF. This categorized the patients into deformity/frailty groups as follows: 19.8% Low-Mod/N-SF(19), 13.5%(13) Sev/N-SF, 44.8%(43) Low-Mod/SF, 21.9%(21) Sev/SF. Logistic regression analysis found a significant relationship between increasing deformity severity and occurrence of severe postop DJK(1.053 [1.016-1.093], p= 0.005), complications(1.045 [1.012 - 1.080], p=0.007), revision by 1-year(1.059 [1.000-1.122], p= 0.049). Additionally, increasing invasiveness and occurrence of severe DJK (1.030 [1.007-1.054], p= 0.024) and revision (1.026 [1.008 - 1.044], p=0.005). Invasiveness increased with deformity and frailty severity: 53.6 Low-Mod/N-SF, 81.4 Sev/N-SF, 56.4 Low-Mod/SF, 79.8 Sev/SF; p=0.002. After defining a favorable outcome as no occurrence of severe DJK, no major complications and no revisions, and 1Y mJOA improvement (28.1%), invasiveness scores were compared within deformity/frailty groups between patients who met/did not meet the favorable outcome. For the NSF deformity groups, those with a favorable outcome had larger invasiveness scores (Low-Mod: 58.7 vs 48.5; Sev: 77.7 vs 89.6). For the SF deformity groups, the favorable outcome had significantly lower invasiveness scores for the Low-Mod deformity group (38.1 vs 62.9, p=0.008), while the Sev/SF deformity favorable outcome group remained larger (86.8 vs 79.4), though this was not significant. For the Low-Mod/SF group an invasiveness cutoff score of <48 where achieving a favorable outcome was 3x higher (3.08[1.2-7.9], p=0.019).
CONCLUSION(S): For SF patients, when deformity severity is low to moderate, surgeons may limit the invasiveness of their procedures in order to account for the patient's susceptibility to poor outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Amidst a current US opioid epidemic, it is important to understand factors that contribute to long-term or sustained opioid use after elective spine surgery. Recent reports have reported up to 25% of opioid-naive patients are taking opioids at 2-year follow-up after adult spinal deformity (ASD) surgery. This suggests ASD surgery, or at least the postoperative course, could be a significant factor contributing to long-term or sustained opioid use. ln Asian countries, opioids are rarely prescribed for postoperative pain. Potentially, there is a significant cultural difference that can play a role in patient expectations in the postoperative period leading to long-term opioid use. PURPOSE: To compare long-term or sustained (2-years) opioid use after ASD surgery between American and Japanese Cohorts STUDY DESIGN/SETTING: Propensity-matched comparison of American and Japanese ASD patients PATIENT SAMPLE: Patients from two (United States vs Japanese) prospective, multicenter ASD databases were compared OUTCOME MEASURES: Baseline and 2-year opioid use and SRS-22 domains were compared METHODS: We propensity matched 127 JPN to 619 US ASD patients based on age, sex, BMI, 3-column osteotomy, pelvic fixation, number of levels fused and preoperative SVA. Pre-op and 2-year postoperative opioid use was determined using responses to SRS22R Q11 and grouped into 3 categories (none, weekly, or daily). We have previously validated the use of SRS22R Q11 as an accurate measure for opioid use by comparing to a prospective study specifically designed to study opioid use and postoperative outcomes in ASD.
RESULT(S): From each cohort, 34 cases were successfully matched, with no difference in baseline parameters, including baseline opioid use (p=0.095), between the cohorts. The relatively low numbers in each cohort arise from difficulty matching a lower BMI and lower baseline opioid use in the JPN cohort. At 2-years postop, 22 US (65%) vs 31 JPN (91%) reported no opioid use, 1 US (3%) vs 0 JPN (0%) reported weekly use, and 11 US (32%) vs 3 JPN (9%) reported daily use (p=0.009). There was no difference in 2-year SRS-22 Self-image and Mental Health between the two groups while US patients had better Satisfaction (4.29 vs 3.84, p=0.032) but lower Function scores (3.52 vs 3.90, p=0.029).
CONCLUSION(S): In propensity-matched ASD cohorts, 35% of US patients were still using opioids 2 years after surgery compared to 9% of JPN patients, with the most taking opioids daily. Further studies are needed to identify sources of this variability. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Distal junctional kyphosis (DJK) is a radiographic finding identified after patients undergo instrumented spinal fusions which can lead to decreased mobility in the affected spinal segments. There is a lack of consensus of the true etiology of DJK, since it is multifactorial in nature. PURPOSE: Develop a novel risk index specific to each patient to minimize postoperative DJK occurrence using distal construct and surgical factors STUDY DESIGN/SETTING: Retrospective review of a single-center comprehensive CD database PATIENT SAMPLE: A total of 110 CD patients (pts) OUTCOME MEASURES: DJK, Health Related Quality of Life, Reoperation, Minimal Clinically Important Difference (MCID) EQ5D.
METHOD(S): CD pts with BL and at least 1Y radiographic parameters were included. A patient-specific DJK score was created through use of unstandardized Beta weights of a multivariate regression model predicting DJK (end of fusion construct to the 2nd distal vertebra change in this angle by <-10degree from BL to postop). The equation consisted of distal construct factors [A) BL-3M inclination angle, B) BL inflection point, C) LIV angle,] and surgical factors [D) combined approach, E) TS-CL, F) PT, G) C2-C7, H) T4-T12, I) osteoporosis]. A BL model was created as a reference that included all of the above factors not including (C2-C7 and T4-T12). Correlations with 2Y outcomes was identified with use of this BL reference score.
RESULT(S): A total of 110 CD pts included (61yrs, 66.4%F, 28.8kg/m2). Of these, 31.8% pts developed DJK (16.1% 3M, 11.4% 6M, 62.9% 1Y). At BL DJK pts were more frail, had more combined approaches, and had more anterior approaches (all p<0.05). Multivariate model regression analysis identified individualized scores through creation of a DJK equation: 1.15+ 0.04 (Inclination) -2.3 (Preinflection) + 0.04 (LIV angle) + 0.78 (combine approach) + 0.09 (TS-CL) + 0.02 (PT) + 0.11 (C2-C7) + 0.02 (T4-T12) + 0.12 (osteoporosis). This equation (min: 0007 and a max: 95.3) has an 86.3% accuracy of predicting DJK. Having a score>81 predicted DJK with an accuracy of 89.3%. The BL reference equation, (-1.3+0.002 [BL inclination score]-1.3 [BL inclination C6 to T1]-0.05 [BL LIV angle] +1.4 [combined approach] + 0.01 [BL PT]-0.023 [osteoporosis]), correlated with 2Y outcomes of NSR-back percentage(p=0.003), reoperation(p=0.04) and MCID for EQ5D(p=0.04).
CONCLUSION(S): This study created a newly proposed risk index that focuses heavily on distal construct and surgical factors. Having a DJK score >81 was associated with an increase in risk of DJK. The reference models created were identified to correlate with 2-year outcomes of NSR-back percentage, reoperation rates and minimal clinically importance difference for EQ5D. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Traditional iliac (IS) and S2-alar-iliac (S2AI) pelvic fixation methods have unique technical characteristics in their application, and result in varied biomechanical and anatomic impact. These differences may lead to variance in lumbopelvic fixation failure types and rates. PURPOSE: We intended to evaluate the influence of type of iliac fixation utilized for adult spinal deformity (ASD) correction on the frequency and manner of lumbopelvic fixation failure. STUDY DESIGN/SETTING: Retrospective review of prospective, multicenter ASD database. PATIENT SAMPLE: This study included 410 patients. OUTCOME MEASURES: HRQL (ODI, SF-36, NRS), rod fracture, screw fracture, screw loosening, revision surgery, pseudarthrosis METHODS: Inclusion criteria included ASD (coronal Cobb>=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree and/or thoracic kyphosis >60degree) >= 18 years old, 2yr follow-up, and >5 level fusion with pelvic fixation. Cohort subdivided by type of pelvic fixation (IS vs S2AI). Loosening was defined by lucency around the screw shank on radiographs. Univariate testing was performed using t-tests and chi-squared tests. Multivariate logistic regression, accounting for significant confounders, was used to examine differences between the two groups for screw loosening/fracture, rod fracture, and revision surgery. Level of significance = p<0.05.
RESULT(S): Of the total of 1422 patients, 410 met inclusion criteria (IS=287, S2AI=131). The two groups had similar age, BMI, baseline co-morbidities, and number of levels fused (p>0.05), as well as similar baseline HRQLs (SF-36, ODI, SRS-22, NRS leg and back, p>0.05) and deformity (PT, PI-LL, SVA, p>0.05). Patients in the IS group had a higher proportion of unilateral fixation compared to S2AI group (12.9% vs 5.6%; p=0.001). The overall pelvic fixation failure rate (screw loosening/screw fracture/rod fracture) was 29.4%. Loosening of pelvic fixation occurred in 13.4% of patients, and was more prevalent in the S2AI fixation group (OR 2.74, p=0.001). The rate of S1 screw loosening was 2.9%, and more likely to occur in the S2AI group (OR 4.17, p=0.045). The rate of pelvic fixation fracture in the overall cohort was 2.3%, with no difference between groups (p=0.37). Rod fracture occurred in 14.1% below L4, with a trend toward less occurrence in the S2AI group (OR 0.47, p=0.06). Revision surgery was required in 22.7% of our cohort, with no difference between groups (p=0.449). Patients with failure of the pelvic fixation had less improvement in their HRQL at 2years (PCS 7.69 vs 10.46 p=0.028; SRS 0.83 vs 1.03 p=0.019; ODI 12.91 vs 19.77 p=0.0016).
CONCLUSION(S): Pelvic fixation is commonly used in long segment adult spinal deformity surgery to improve the rate of L5-S1 fusion and protect from construct failure at the lumbosacral junction. Our results demonstrate a substantial rate of pelvic fixation hardware issues following ASD correction. Lumbopelvic fixation failure occurred at a rate of 29.4% following surgical correction of ASD that involved iliac fixation and was associated with diminished clinical outcomes. Additionally, S2AI screws were more likely to demonstrate loosening, but less commonly associated with rod fractures. Patients who experienced failure of their pelvic fixation had less improvement in their HRQL two years postoperatively. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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STUDY DESIGN/UNASSIGNED:Cadaveric study. OBJECTIVE/UNASSIGNED:To evaluate accuracy, radiation exposure, and surgical time of a new robotic-assisted navigation (RAN) platform compared with freehand techniques in conventional open and percutaneous procedures. METHODS/UNASSIGNED:Ten board-certified surgeons inserted 16 pedicle screws at T10-L5 (n = 40 per technique) in 10 human cadaveric torsos. Pedicle screws were inserted with (1) conventional MIS technique (L2-L5, patient left pedicles), (2) MIS RAN (L2-L5, patient right pedicles), (3) conventional open technique (T10-L1, patient left pedicles), and (4) open RAN (T10-L1, patient right pedicles). Output included (1) operative time, (2) number of fluoroscopic images, and (3) screw accuracy. RESULTS/UNASSIGNED:= .650). CONCLUSION/UNASSIGNED:RAN significantly improved accuracy and decreased radiation exposure in comparison to freehand techniques in both conventional open and percutaneous surgical procedures in cadavers. RAN significantly increased setup time compared with both conventional procedures.

BACKGROUND CONTEXT: Following cervical deformity (CD) corrective surgery, durability remains a challenge and distal junctional kyphosis (DJK) is an important risk for a surgeon to consider. DJK is the result from fixation failure, adjacent level fracture or spondylolisthesis. The timing of DJK onset has yet to be investigated. PURPOSE: To determine the timing of DJK development following CD corrective surgery. STUDY DESIGN/SETTING: Retrospective review. PATIENT SAMPLE: A total of 139 CD patients. OUTCOME MEASURES: Early/Late DJK Development, Severe DJK, Symptomatic DJK.
METHOD(S): Included: surgical CD patients (C2-C7 Cobb>10degree, CL>10degree, cSVA>4cm, or CBVA>25degree) without preop DJK. DJK angle was defined as the change in kyphosis between lower-most instrumented vertebra (LIV) and LIV-2 from preop to postop (<-10). X2 analysis and post-hoc testing assessed annual and overall incidence of early (3M follow-u) and late (DJK development at 6M, 1Y, 2Y) DJK development among operative patients. Differences between early and late DJK (development after 3 months) were assessed. Pearson correlations determined significant variables associated with development of early versus late DJK. Severe DJK was defined as DJK angle <-20degree. DJK was considered symptomatic if associated with reoperation or the previously published thresholds of NDI>24 or mJOA<14. The natural progression of the disease was predicted with the use of a Kaplan-Meier survivorship analysis.
RESULT(S): A total of 139 patients without preop DJK were included (16 re-op) (61.8yrs, 62.3%F, 29.1kg/m2). Surgical characteristics: 20.1% anterior approach, 42.4% posterior, 36.7% combined (levels fused: 7.6). Incidence of DJK from 2013-2018: 23%. Early: 9.4%, late: 10.1% (6M delayed: 3.6%, 1Y delayed: 6.5%, 2Y delayed: 2.2%). No differences were observed between op and reop for development of early or late DJK at all f/u (p>0.050). Presence of upgoing plantar response at baseline neuro exam, C2-C7 angle, T1-C2 angle, CBVA and combined approach correlated with development of early DJK. For late DJK: history of tumor and pulmonary disease, pelvic incidence, T10-L2 angle, and L4 pelvic angle. Apex of the secondary driver was significantly lower in the Late group (mean early: T2/3; late: T10; p=0.023). 3M radiographically, Early DJK patients had greater TK (-57.9degree vs -40degree, p=0.024, while L4PA remained larger in the late DJK group (14.5degree, p=0.009). Between early and late groups, 41.7% of early DJK patients met criteria for severe DJK, while 0% of Late DJK patient were severe(p=0.010); symptomatic DJK between the two groups was not significant (p=0.941). Kaplan-Meier survivorship analysis determined patients within the cohort to have a 91.1% cumulative probability of maintaining non-DJK status by 3-month follow-up, 85.9% at 6-month, 80% at 1-year, and 77.0% by 2-year follow-up.
CONCLUSION(S): Patients undergoing CD corrective surgery have incidence of early and incidence of late DJK. While the majority of DJK development occurs within the first 6 months, late DJK occurs and differs in presentation and etiologic factors. Early DJK occurrence is more likely to be severe radiographically, associated with neurological decline, and is more strongly related to biomechanical factors such as use of a combined approach at the time of surgery. Contrarily, although equally likely to be symptomatic as reflected in loss of clinical gains from surgery, late DJK is more likely mild radiographically and associated with suboptimal cervical realignment and lack of addressing secondary drivers, likely related to negative compensatory mechanisms. Customized prophylactic approaches for both occurrences is mandated. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The Scoliosis Research Society established appropriateness criteria for surgery for degenerative lumbar scoliosis (DLS) in order to improve and unify clinical decision making. Though utilized and validated in various cohorts, an appropriateness criteria has yet to be developed in a cervical deformity (CD) population. PURPOSE: To modify the DLS Appropriateness criteria to be utilized in a CD cohort. STUDY DESIGN/SETTING: Retrospective review of a single-surgeon CD database PATIENT SAMPLE: A total of 100 CD patients. OUTCOME MEASURES: Appropriateness criteria.
METHOD(S): CD patients>18yrs were included. Each patient was scored based upon the SRS-appropriateness criteria, comprised of clinical or radiographic characteristics and was modified for a cervical deformity cohort: (1) Severity of Symptoms [NDI], (2) Severity of Myelopathy[mJOA.], (3) Progression of Deformity, (4) Global Sagittal Malalignment [Schwab modifiers], (5) Severity of Risk Factors, (6) Degree of the T1S-CL curvature. For the category 'progression', radiographs were only available at one preoperative time point, and we were unable to include this in the total score. Based upon certain combinations of criteria, patients were stratified into Appropriate and Not Appropriate.
RESULT(S): A total of 100 patients were included (61yrs, 62% F, 29.5kg/m²). Assessment of the categories of Appropriateness of CD surgery: (1) Symptoms: 6% None to Mild, 94% Moderate to Severe; (2) Myelopathy: 16% None to Mild, 45% Moderate, 39% Severe; (3) All were grouped No Progression in the present study; (4) 19% demonstrated Global Malalignment (+/++Schwab), 81% did not; (5) Risk Factors: 27% had None to Mild, 63% Moderate, 10% Severe; (6) Curvature TS-CL demonstrated 88.6% of patients Severe (>20degree). Not Appropriate: None to Mild (NDI <28), with (1) None to Moderate myelopathy (mJOA >12) and Severe Risk Factors (2) None to Mild myelopathy (15-18) and No Progression or Imbalance (3) Moderate myelopathy (mJOA 12-15) and None to Moderate Risk Factors and no Progression, or imbalance and TSCL <25degree. Appropriate: Moderate to Severe Symptoms (NDI >=30), with (1) Severe myelopathy (mJOA<12) and Any Risk Factors (2) Moderate myelopathy and None to Moderate Risk Factors (3) Moderate myelopathy with Severe Risk Factors, Progression AND Imbalance (4) None to Mild myelopathy and None to Moderate Risk Factors and Progression OR imbalance (5) None to Mild myelopathy with None to Moderate Risk Factors and TSCL >25degree. In the present cohort, 94% were deemed Appropriate for surgery, 6% Not Appropriate. Less Appropriate patients demonstrated higher rates of postop dysphagia complications (17% vs 2%), met MCID for NDI less (0% vs 30.9%), and had more occurrences of DJK (16.7% vs 6.4%) by 2 years, p<0.05.
CONCLUSION(S): In light of the heterogeneity and uncertainty surrounding CD, this study developed CD appropriateness criteria, using established methodology, for surgeons to consider in the preoperative decision-making that correlate well with major postop occurrences. Application of the appropriateness criteria for CD may optimize patient selection and reduce the incidence of unwarranted surgery, although future validation is necessary. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Chiari malformations (CM) are congenital or acquired hind brain anomalies with resultant cerebellar tonsillar herniation through the foramen magnum. Chiari I malformation consists of herniation of the cerebellar tonsils into the foramen magnum thus crowding the craniocervcial junction. Surgical management is variable among these type 1 patients(pts) based on their presenting symptoms. PURPOSE: Identify complication rates following CM surgery. STUDY DESIGN/SETTING: Retrospective cohort study of (Kids' Inpatient Database) KID. PATIENT SAMPLE: Chiari Malformation Type I. OUTCOME MEASURES: Complication rates, fusion, decompression, duroplasty, laminectomy, LOS, Readmission.
METHOD(S): The KID database was queried for diagnoses of operative Chiari Malformation from 2003-2012 by ICD-9 codes (348.4). Differences in preoperative demographics (age/BMI) and perioperative complication rates between patient cohorts were assessed using Pearson's chi-squared tests and T-tests when necessary. Binary logistic regression were utilized to find significant factors associated with complication rate. Decision tree analysis was utilized for continuous variables predictive of complication rate. Certain surgical procedures were analyzed for their relationship with post-operative outcomes.
RESULT(S): A total of 13,812 CM-1 patients were isolated (10.12 yrs, 0.62 CCI). Of these pts, 8.2% (1,128) received a complication. From 2003 to 2012, the rate of complications for CM-1 pts decreased significantly (9.6%-5.1%) along with surgical rate (33.3%-28.6%), despite the increase in CM diagnosis (36.3%-42.3%; all p<0.05). CM-1 pts who had a complication were younger (9.73+/-6.8 yrs vs 10.2+/-6.3 yrs) and had a lower invasiveness score (0.35+/-1.0 vs 0.41+/-1.0), however; they had a larger CCI (1.10+/-1.6 vs 0.6+/-1.3) than those who did not have a complication (all p<0.05). The most prevalent comorbidities for these pts were cerebrovascular (16.67%), malignancy (11.6%), pulmonary (9.6%), and renal (7.1%; all p<0.05). CM-1 pts who experienced complications had a concurrent diagnosis of syringomyelia (7.1%) and also Scoliosis (3.2%; all p<0.05). CM-1 pts who did not have a complication had a greater surgical rate than those that had a complication (76.4% vs 23.6% p<0.05). Having an interbody instrument, having an invasiveness score>4.25 and receiving a fusion greater than 4 levels were all significant factors associated with receiving a complication postoperatively (p<0.05). The most common complication was nervous system related (2.8%), anemia (2.4%), and acute respiratory distress (2.1%). CM-1 pts that underwent a fusion (3.4% vs 2.1%) had greater complication rates as well as those that underwent a craniotomy (23.2% vs 19.1%; all p<0.05). However, CM-1 pts who underwent a decompression had lower postop complications (21.3% vs 28.9%; all p<0.05). A total of 13,812 CM-1 patients isolated (10.12 yrs, 0.62 CCI). Of these pts, 8.2% (1,128) received a complication. From 2003 to 2012, the rate of complications for CM-1 pts decreased significantly (9.6%-5.1%) along with surgical rate (33.3%-28.6%), despite the increase in CM diagnosis (36.3%-42.3%; all p<0.05). CM-1 pts who had a complication were younger (9.73+/-6.8yrs vs 10.2+/-6.3yrs) and had a lower invasiveness score (0.35+/-1.0 vs 0.41+/-1.0), however; they had a larger CCI (1.10+/-1.6 vs 0.6+/-1.3) than those who did not have a complication (all p<0.05). The most prevalent comorbidities for these pts were cerebrovascular (16.67%), malignancy (11.6%), pulmonary (9.6%), and renal (7.1%; all p<0.05). CM-1 pts who experienced complications had a concurrent diagnosis of syringomyelia (7.1%) and also Scoliosis (3.2%; all p<0.05). CM-1 pts who did not have a complication had a greater surgical rate than those that had a complication (76.4% vs 23.6% p<0.05). Having an interbody instrument, having an invasiveness score>4.25 and receiving a fusion greater than 4 levels were all significant factors associated with receiving a complication postoperatively (p<0.05). The most common complication was nervous system related (2.8%), anemia (2.4%), and acute respiratory distress (2.1%). CM-1 pts that underwent a fusion (3.4% vs 2.1%) had greater complication rates as well as those that underwent a craniotomy (23.2% vs 19.1%; all p<0.05). However, CM-1 pts that underwent a decompression had lower postop complications (21.3% vs 28.9%; all p<0.05).
CONCLUSION(S): Treatment of Chiari malformation has been identified to have improved from 2003 to 2012 with increased identification of diagnosis and decreased complications. Chiari patients undergoing fusions and craniotomies are at a greater risk of postoperative complications especially when the instrumented fusions are performed on >4 levels. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The impact of neuromuscular disorders such as multiple sclerosis (MS) on outcomes following anterior cervical discectomy and fusion (ACDF) is underreported. PURPOSE: Identify the impact of MS on two-year (2Y) postoperative complications and revisions following 2-3-level ACDF for cervical radiculopathy (CR) or myelopathy (CM). STUDY DESIGN/SETTING: Retrospective review of the New York State Statewide Planning and Research Cooperative System (SPARCS) database. PATIENT SAMPLE: Patients undergoing 2-3 level ACDF for CR/CM. OUTCOME MEASURES: Two-year postoperative complications and reoperations.
METHOD(S): Patients undergoing 2-3 level ACDF for CR/CM were identified from SPARCS. Patients with a baseline diagnosis of MS were also identified. Patients with infectious/traumatic/neoplastic were excluded. The remaining patients were 1:1 propensity score-matched (MS to no-MS) for age, sex, race, Deyo index and compared for rates of 2Y postoperative complications and reoperations. Logistic regression models were utilized to determine significant predictors of these outcomes.
RESULT(S): A total of 302 total patients were identified (MS, n=151; non-MS, n=151). MS patients were more frequently female (72.8% vs 27.2%, p<0.001). Age was comparable (50.1 vs 50.1 years, p=0.225). MS patients incurred higher charges for their surgical visit ($41,029 vs $31,654) and higher LOS (2.8 vs 2.2 days), both p<=0.016. They experienced higher rates of deep vein thrombosis (DVT) (3.3% vs 0%, p=0.02), with similar overall medical (19.2% vs 21.2%), surgical (7.9% vs 10.6%), and total complications (21.9% vs 25.8%), all p>0.05. MS patients had similar rates of 2Y revisions (6.6% vs 5.3%, p=0.627). MS was not associated with medical, surgical, or overall complications or revisions at minimum 2Y follow-up.
CONCLUSION(S): Despite differences in demographics and higher rates of postoperative DVT, MS patients experienced comparable postoperative course with respect to other individual and overall complications and revisions following 2-3-level CF for degenerative spinal pathologies. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Adult spinal deformity (ASD) corrective surgery is often associated with high rates of adverse outcomes during the recovery course. With the growth of predictive analytics in the medical field, it is important to utilize the developing machine-learning resources to consider the risks associated with major operations. PURPOSE: To assess the validity of the ACS-NSQIP risk index for postop complications and mortality in a prospective multicenter ASD database. STUDY DESIGN/SETTING: Retrospective cohort study of a prospective multicenter ASD database PATIENT SAMPLE: A total of 1,281 ASD patients. OUTCOME MEASURES: Predictive performance of the ACS-NSQIP calculator in an ASD database.
METHOD(S): Patients>18yrs undergoing surgery for ASD (scoliosis>=20degree, SVA>=5cm, PT>=25degree or TK>=60degree). Calculated perioperative complication risk averages via the ACS-NSQIP surgical calculator with CPT codes were compared with 30-day complication rates in the ASD database. Outcomes assessed (as defined by NSQIP): serious complication, any complication, pneumonia, cardiac complication, SSI, UTI, VTE, renal failure, return to OR, death, sepsis and length of hospital stay. Predictive performance of the calculator was analyzed by Brier score (sum of squared differences between the binary outcome and the predicted risk). It ranges from 0 to a maximum Brier score [(mean observed outcome)*(1-[mean observed outcome])]. Values closer to 0 are suggestive of better predictive performance (>0.05 considered poor). Length of stay was assessed with a Bland-Altman plot, observed LOS on the x-axis and the difference between the observed and predicted LOS on the y-axis. Performance of the calculator for serious/any complications for surgeries indicated as 'Risk significantly higher than estimate' was assessed by comparing means of patients who were in the top quartile for their ISSG-invasiveness scores.
RESULT(S): A total of 1,281 ASD patients (60.2 yrs, 73.5% F, 28 kg/m2) were included. A total of 49.4% of procedures involved decompression and 100% involved fusion, with a mean number of levels fused of 10.98. The means for individual patient characteristics that coincide with the variables entered into the online risk calculator interface are as follows: functional status through baseline ODI scores (Independent [0-40]: 35.6%, Partially Dependent [41-80]: 61.8%, Totally Dependent [81+]: 2.6%), 0% emergent cases, ASA Class (I: 5.6%, II: 46.8%, III: 41.7%, IV: 1.4%, V: 0%), 11.9% disseminated cancer, 9.1% diabetes mellitus, 36.5% use of hypertensive medications, 10.8% CHF, 5.9% current smoker, 5.2% COPD, and 4.4% acute renal failure. Predictive of any 30-day postoperative complications ranged from 2.8-18.5% across CPT codes, where the actual rate in the cohort was 9.0%, and demonstrated good predictive performance via Brier Score (0.00064516, Max: 0.00819), as well as pneumonia, SSI, UTI, VTE, renal failure, death and sepsis (Brier Max: 0-0.01458096). Serious and cardiac complications, as well as return to OR were poorly predicted via the NSQIP risk index (Brier Max > 0.05). Mean difference between observed and predicted LOS was 4.276 days with a 95% confidence interval of 9.484 - -0.932. When indicated for significantly high risk, the calculator poorly predicted overall and serious complications (Brier Max >0.1).
CONCLUSION(S): While the ACS-NSQIP risk index had acceptable predictive performance in regards to the occurrence of overall post-operative complications, notable exceptions were detected. Specifically, deficiencies in assessing serious complications, cardiac complication and return to OR were seen, and performance was noted to diminish with procedures of greater invasiveness. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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