Faculty Bibliography

BACKGROUND CONTEXT: The International Spine Study Group (ISSG) and the European Spine Study Group (ESSG) developed an adult spinal deformity (ASD) specific risk calculator based on the largest and most granular, prospective ASD database. The calculators utilize preoperative radiographic, surgical, and patient-specific variables in order to predict patient-reported outcomes and complication rates at 2 years. PURPOSE: Assess the ISSG-ESSG risk calculator usability in a single institution ASD population. STUDY DESIGN/SETTING: Retrospective cohort study- single surgeon institution. PATIENT SAMPLE: ASD pts: A total of 631 patients undergoing surgery for adult spinal deformity. OUTCOME MEASURES: Improvement from BL SRS-22 [Pain, Function, total], major complications, Oswestry Disability Index (ODI).
METHOD(S): ASD pts were isolated in the single-center ASD Database 2013-2020. Frail pts were isolated (Frail[F] 0.3>0.5). Basic demographics were assessed for these F pts via chi-squared and t-tests. Each F patient was inputted into the ESSG risk calculator to identify individual predictive rates for postoperative 2-year HRQL outcomes as well as major complications. These calculated predicted outcomes were analyzed against those identified from the ASD database in order to validate the calculator predictability in a single center institution via Brier scores. Having a score closer to 1 means the EESG calculator is not predictive of that specific outcome. A score closer to 0 meant the EESG calculator was a predictive tool for that factor.
RESULT(S): A total of 631 ASD pts were isolated (55.8;16.8yrs, 26.68kg/m², 0.95+/-1.3CCI). Of these patients, 7.8% were frail. Fifty percent of frail pts received an interbody fusion, 58.3% received a decompression, and 79.2% had an osteotomy. Surgical details: mean operative time 342.9+/-94.3minutes, mean estimated blood loss 2131.82+/-1011mL, and an average length of stay 7.12+/-2.5days. The EESG calculator predicted the likelihood of improvement for the following HRQL's ODI(86%), SRS-22 Mental Health (71.1%), SRS-22 Total (87.6%), major complication (53.4%). The single institution had lower percentages of improvement in ODI (24.6%), SRS-22 Mental Health (21.3%), SRS-22 Total (25.1%), and lower presence of major complication (34.8%). The calculated Brier scores identified the calculator's predictability for each factor: ODI (0.24), SRS-22 Mental Health (0.21), SRS-22 Total (0.25), major complication (0.28).
CONCLUSION(S): The newly developed ESSG-ISSG risk-assessment tool has a wide application in single institutions as it accurately predicts 2-year outcomes for various SRS-22 questionnaires and development of major complications. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Although researchers have extensively studied factors predicting clinical outcomes at static time points, assessing rate of recovery after adult spinal deformity (ASD) surgery has largely been ignored. This study aims to address this gap in knowledge by evaluating the impact of frailty and invasiveness on recovery kinetics, using area-under-the-curve (AUC) methodology. PURPOSE: To assess the impact of patient specific and surgical factors on postoperative recovery kinetics. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter database. PATIENT SAMPLE: A total of 320 patients were identified from a multicenter database who had minimum 2-year HRQOL follow-up, with preoperative, 6-week and 1-year data available. OUTCOME MEASURES: Our primary outcome measure was integrated health state (IHS) score, a marker of postoperative recovery.
METHOD(S): ASD patients with minimum 2-year follow-up were stratified by frailty and surgical invasiveness. Previously validated ASD-FI scores were used to separate non-frail (<.3) patients from those that there were frail (.3 to.5) and severely frail (>.5). Patients were also stratified by surgical inverness, using ASD-SR, into four quartiles, Q1: <65, Q2: 66-89, Q3: 90-119, Q4: >120. Patient demographics, BMI, CCI and surgical parameters were also collected. To assess recovery kinetics, SRS-22r and ODI scores at 6-weeks, 1-year and 2-year were normalized against preoperative values and graphed as a function of time. AUC was summed across all time points to generate a single IHS score. Multivariate linear regression was used with IHS scores as primary outcome variable.
RESULT(S): A total of 320 patients met the inclusion and exclusion criteria. The mean (SD) patient age was 58.6 (14.7) with 79% female. Overall, 139 were non-frail, 131 frail and 46 severely frail. On univariate analysis, frail and severely frail patients were noted to have worse baseline and 2-year HRQOL scores for SRS pain, activity and ODI; however, when comparing differences in HRQOL across this 2-year period, F and SF were noted to have greater improvements in both SRS and ODI (p<.05). On multivariate regression, frail and severely frail patients, compared to those non-frail, were found to have better IHS scores for ODI, SRS-22r pain, and SRS-22r activity, indicating more favorable recovery (p<.05). In particular, for SRS-22r activity, frail (adjusted beta: 0.37, p=<.01) and severely frail (adjusted beta: 0.74, p=<.01) patients were found to have higher IHS compared to their non-frail counterparts. Similarly, for SRS-22r pain, frail and severely frail patients showed improved recovery with higher IHS scores in comparison to non-frail patients. In contrast to frailty, operative variables, including surgical invasiveness and EBL, were insignificant predictors of IHS scores for either ODI or SRS-22r domains.
CONCLUSION(S): Our results suggest that patient-specific factors, namely frailty, play a larger role in predicting postoperative recovery kinetics, in comparison to surgical factors, which appear to have limited if any impact. Despite frail patients having lower preoperative and 2-year HRQOL scores, they were noted to have higher IHS scores SRS pain, activity, and ODI indicating more favorable recovery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: For surgical adult spinal deformity (ASD) patients, determining optimal restoration of alignment and spinal shape is an active area of research. Complex corrective measures taken are in ASD. Incidence of specific alignment outcomes has yet to be investigated in each of the complex realignment ideals. PURPOSE: Assess alignment outcomes (pelvic nonresponse [PNR], PJK, postop cervical deformity [CD]) following ASD-corrective surgery in the context of correction relative to various alignment schemas. STUDY DESIGN/SETTING: Retrospective cohort study of prospective ASD database. PATIENT SAMPLE: A total of 468 ASD patients. OUTCOME MEASURES: PNR, PJK, postop CD.
METHOD(S): ASD patients with preop, 6-week postop (6W), and 2-year postop (2Y) radiographic data included. PNR: 10-year mismatch (undercorrection; unimproved) from a patient's age-adjusted PT at 6W and maintained at 2Y. Pelvic responder (PR): PT +/-10 match age-adjusted goals. Patients were stratified by incremental additions of corrective alignment schemas: (a) improvement in Schwab SVA, (b) matching age-adjusted PI-LL, (c) match postop "ideal" and "theoretical" Roussouly, (d) improvement in proportionality spinal score at 6W. PNR, PJK, and CD development by 2Y were compared within groups, as well as simultaneous improvement/match of the suggested corrective measures (exclusively). In a subanalysis, patients were stratified by severity of baseline PT, low (<20degree), moderate (20-30degree), and severe (>30degree) to determine which alignment schema is necessary to achieve less PNR, PJK and postop CD.
RESULT(S): A total of 468 patients (56.3 yrs, 76.5% F; 25.6% PNR, 40.6% PR) met inclusion criteria. Rates of postop PJK (PNR:49.2% vs PR:59.5%) and CD (18.3% vs 25.8%) were significantly less in the PNR group, p<0.05. Sole improvement in Schwab SVA (73.2%) did not impact PNR, PJK or CD (p>0.050). Undercorrected age-adjusted PI-LL presented with more PNR (60.1%), whereas overcorrected had increased PJK (68.2%), p<0.001. Matching Roussouly at 6W decreased PNR (17.8% vs mismatch:42.3%, p=0.002). 6W proportional spine, had lower rates of PNR (19.7%, severely disproportioned: 58.8%, p<0.001), with postop moderately disproportioned GAP with highest rates of PJK (p=0.010). Incremental addition of alignment schemas was assessed for effect on malalignment outcomes. Schwab and age-adjusted use (20.9%) had less incidence of PNR (28.6% vs 38.7%) than just Schwab. Addition of the Roussouly (18.3%) presented with less PNR (20% vs 30.4%) and PJK (38.5% vs 60.3%) than only Schwab & age-adjusted. Lastly, addition of proportion (16.7%) had 0% occurrence of PNR and CD. Stratifying by baseline PT severity, the low group demonstrated the least incidence of PNR (7.7%) and CD (10.3%) and PJK (41.3%) when matching theoretical Roussouly at 6W (all p<0.050). This remained the same for moderate PT for PNR and PJK, except Schwab improvement decreased postop CD occurrence (21.2%, p=0.049). Severe PT assessment determined PNR (20%), PJK (37.5%) and CD (19.4%) were the lowest with improvement of proportion at 6W (p<0.050).
CONCLUSION(S): Following ASD corrective surgery, 25.6% of patients showed residual pelvic malalignment, qualifying as pelvic nonresponders. Use of complex realignment schemas (SRS-Schwab, age-adjusted, Roussouly shape, GAP) decreased rates of pelvic nonresponse, PJK and postop cervical deformity development. Severe (>30degree) baseline pelvic tilt requires particular emphasis of proportionality in addition to other realignment ideals. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Recombinant human bone morphogenetic protein 2 (BMP) is increasingly utilized in minimally invasive (MIS) transforaminal lumbar interbody fusions (TLIF) in order to increase rate of fusion by promoting bone growth through the induction of osteoblast differentiation, awhile reducing morbidity related to iliac crest autograft. Despite these benefits, BMP use is still controversial due to its pro-inflammatory mechanism of action and potential to cause radiculitis. PURPOSE: To assess whether BMP is a risk factor for postoperative radiculitis in TLIF. STUDY DESIGN/SETTING: Single-center retrospective cohort study. PATIENT SAMPLE: A total of 397 TLIFs from June 2012 to December 2018. OUTCOME MEASURES: Perioperative clinical characteristics, post-operative risk of radiculitis and complication, and future reoperation rates.
METHOD(S): Patients >= 18 years-old undergoing elective single-level TLIFs from 2012 to 2018 were included. Outcome measures included perioperative clinical characteristics, postoperative risk of radiculitis and complication, and future reoperation rates. Radiculitis was defined the delayed onset of radicular symptoms postoperatively in patients whom had initial resolution of radicular symptoms immediately postoperatively, in the absence of persistent neurological compression on postoperative imaging. Statistical analyses included independent t-tests and chi-square analysis. Propensity score matching was utilized to control for demographic differences between the groups. Independent predictors for post-operative radiculitis were assessed by multivariate logistic regression. Significance set at p<0.05.
RESULT(S): A total of 397 cases were included in the study (59.33 +/- 13.49 mean age, 28.98 +/- 6.29 mean BMI, 52.90% female, 2.29 +/- 1.92 average Charleston comorbidity Index). There were 223 open procedures and 174 MIS. For the entire cohort, 238 cases utilized BMP and 159 did not, with 102 MIS pairing with BMP use. The MIS TLIFs had a higher percentage of BMP use than open TLIFs (58.6% vs 25.7%, p<0.001), lower estimated blood loss (212.28 +/- 193.79 mL vs 410.91 +/- 337.98 mL, p<0.001) higher fluoroscopy dosage (52.43 +/- 48.61mGy vs 16.77 +/- 27.84mGy, p<0.001), and a lower length of stay (3.20 +/- 2.55 days vs 4.11 +/- 2.52 days, p<0.001). There were no other differences in perioperative clinical characteristics. There was a significantly higher rate of postoperative radiculitis in the MIS TLIFs compared to open (12.6% vs 6.8%, p=0.046) and use of BMP compared to no BMP (13.2% vs 6.7%, p=0.029). There was a 15.7% radiculitis rate when MIS was paired with BMP use. There were no other notable differences in complication rates or rates of reoperation. Individually, MIS had a 12.6% radiculitis rate (p=0.046) and BMP use had a 13.2% rate (p=0.029). Propensity score match controlled for the significant difference in CCI between the MIS and open groups (N=168 each). Multivariate regression indicated that MIS (p=0.314) and BMP (p=0.109) were not independent predictors individually when controlling for age, gender, and BMI. When technique was paired with biologic use the regression revealed MIS + BMP is a risk factor of post-operative radiculitis (2.265(4.753-1.079), p=0.031).
CONCLUSION(S): While BMP and MIS technique were not independent risk factors for postoperative radiculitis, there is an increased risk of radiculitis when using BMP in MIS TLIF. 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) surgery is complex and may lead to new-onset cervical malalignment and/or proximal junctional kyphosis (PJK). Roussouly et al describes variations in baseline thoracolumbar (TL) shape (Types 1-4), which have been shown to differentially influence surgical ASD outcomes. The effect of morphological shape on patterns of postoperative CD development remains underexplored. PURPOSE: Stratify patients by Roussouly type and assess patterns of conversion from baseline (BL) cervical alignment to postoperative cervical deformity (CD) in patients undergoing thoracolumbar ASD surgery. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter database of ASD patients. PATIENT SAMPLE: A total of 266 surgical ASD patients. OUTCOME MEASURES: Rate and timing of conversion to CD, rate of PJK, radiographic alignment parameters.
METHOD(S): Operative ASD patients with complete radiographic data at baseline, 6W, 1Y, 2Y, & 3Y intervals were included. Patients were grouped by baseline PI and apex of LL into component types of the Roussouly classification system utilizing pelvic incidence as published by Pizones et al. Patients with no BL CD were postoperatively stratified by Ames CD criteria (TS-CL>20 degree, cSVA>40mm), where CD was defined as fulfilling >1 criteria. Follow-up intervals were established post-ASD surgery, with 6W postop defined as "Early," 6W-1Y "Intermediate," 1-2Y "Late," and 2-3Y "Long." Univariate and Cox regression analyses identified CD conversion rate and PJK rate (<-10degree change in UIV and UIV+2) across Roussouly types 1-4.
RESULT(S): A total of 266 surgical ASD patients (59.7yrs, 77.4% F) with complete radiographic data were included. By Roussouly classification, 9% were Type 1, 15.8% Type 2, 46.6% Type 3, and 28.6% Type 4. 28.6% of ASD patients converted to postop CD (Early: 14.3%, Intermediate: 5.3%, Late: 4.1%, Long: 4.9%). There were no significant differences in CD conversion rate across Roussouly types (1: 33.3%; 2: 28.6%; 3: 26.6%; 4: 30.3%, P=0.895). Types 2 (41.7%), 3 (60.6%), and 4 (43.5%) had their peak rates of conversion in the Early (<6w) window compared to other follow-up intervals, whereas Type 1 patients had a peak rate (50%) between 6w-1Y. Type 2 patients had higher rates of later CD conversion (>1 year) than other types (50% vs 28.1%, P=0.135), while Type 1 patients trended higher rates of earlier CD conversion (<1 year) than other types (33.8% vs 12.5%, P=0.220); these patterns did not reach statistical significance. Across Roussouly Types, among patients who converted to CD, Type 4 had significantly higher rates of ++ SRS-Schwab PT and greater TPA at BL (both p<0.05). Type 4 patients had the highest rate of concurrent PJK with CD conversion (60.9%) compared to Type 1 (50%), Type 2 (50%), or Type 3 (54.5%) (P>0.05). There were no significant change in ODI, PCS, or SRS total among Roussouly Types in patients that converted to CD (p>0.05). Random forest analysis determined the top surgical (levels fused), radiographic (TS-CL), and demographic (frailty) factors associated with CD conversion.
CONCLUSION(S): Baseline thoracolumbar shape as described by the Roussouly classification has a differential effect on timing to CD conversion, though overall rates of CD conversion after TL-ASD correction were similar across Types 1-4. Type 1 patients with a lower apex of lumbar lordosis trended earlier conversion, while Type 2 patients with a higher apex of LL trended conversion beyond 1-year postop. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: With a heightened focus on prescription narcotic use in the United States, concern among surgeons has increased regarding preoperative and postoperative usage. However, the literature is scarce on outcomes of preoperative and prolonged opioid usage in adult spinal deformity (ASD) patients. PURPOSE: Investigate effect of preoperative opioid usage on prolonged opioid use postoperatively and rates of reoperations. STUDY DESIGN/SETTING: Retrospective review of the PearlDiver Database 2008-2013. PATIENT SAMPLE: A total of 7,661 ASD patients. OUTCOME MEASURES: Reoperations, 90-day complications, comorbidity burden, prolonged opioid usage METHODS: ASD patients undergoing a fusion were isolated in the PearlDiver database between the years 2008-2013 using ICD-9 and CPT codes. Patients were stratified by prescription preoperative opioid use 3 months prior to surgery: (1) high frequency (>4 refills); (2) low frequency (1-3 refills); (3) opioid naive. Means comparison tests compared differences in demographics, complications, and reoperation rates. Logistic regression assessed the odds of complication and reoperations associated with preoperative frequency and prolonged opioid use (3 to 6 months postop), controlling for age, sex, and comorbidities.
RESULT(S): A total of 7,661 ASD patients were isolated; 2,342 patients were high frequency preop opioid users, 2,247 low frequency preop opioid users, and 3,072 opioid naive. At BL, high frequency preop opioid users had higher rates of obesity, diabetes mellitus, CHF, COPD, hypertension, smoking and alcohol use (all p<0.001). Compared to opioid naive patients, low frequency preop opioid users had higher rates of 90-day complications associated with hematoma and transfusion (p<0.05). High frequency preop opioid users relative to naive opioid users had significantly increased 90-day complication rates including pulmonary embolism, pneumonia, hematoma, and transfusions. High frequency opioid use was associated with increased odds of wound disruption (1.74[1.22-2.51]) and hospital readmission (1.42[1.22-1.64], both p<0.05). Additionally, high frequency opioid usage preop followed by prolonged opioid use postop was associated with increased odds of reoperations at 2Y relative to low frequency (1.67[1.34-2.10]) and opioid naive patients (1.83[1.40-2.42], both p<0.001).
CONCLUSION(S): Patients with high frequency preoperative opioid use are at increased risk of major complications within 90 days of surgery, prolonged use postoperatively, and increased risk of reoperations within two years. During preoperative risk assessment, providers should consider the effect of pre- and postoperative opioid usage on patient outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: MBDs are often implicated in or contribute to degenerative disc disease (DDD). Yet, there is limited long-term, postoperative outcome data on the impact of MBDs on 2-year outcomes following 2-3-level lumbar fusion for DDD. PURPOSE: To determine if DDD patients with MBDs have comparable outcomes to those without MBDs following lumbar fusion. STUDY DESIGN/SETTING: Retrospective cohort. PATIENT SAMPLE: New York State Statewide Planning and Research Cooperative System was reviewed from 2009-2013 to identify all patients with DDD who underwent short, lumbar fusion (2-3-levels) with >=2-year follow-up OUTCOME MEASURES: Two-year outcome rates (medical/surgical complications and reoperations).
METHOD(S): The New York State Statewide Planning and Research Cooperative System was reviewed from 2009-2013 to identify all patients with DDD who underwent short, lumbar fusion (2-3 levels) with >=2-year follow-up. Patients with and without MBD (vitamin D deficiency, hyperparathyroidism, osteomalacia, and rickets) were identified. Any patients with osteoporosis or other systemic/endocrine disorders affecting bone quality were excluded. Traumatic, infectious, and neoplastic surgical indications were excluded. Cohorts were compared for demographics and 2-year outcome rates (medical/surgical complications and reoperations). Logistic regression was used to identify covariates associated with medical/surgical complications and revisions.
RESULT(S): A total of 28,959 patients were included (MBD, n=380 (1.33%); no-MBD, n=28,579). MBD pts were older (56.4 vs 53.1 years) and more often female (65.5% vs 49.80%) than no-MBD pts (all p<0.001). MBD pts had longer hospital stays (4.57 days vs 4.11 days, p=0.026), but charges were similar. MBD pts incurred higher rates of wound complications (11.8% vs 6.0%), acute renal failure (11.1% vs 4.7%), pneumonia (9.2% vs 4.4%), and implant related complications (12.1% vs 7.0%); all p<0.001. Rates of pseudarthrosis, PE, pulmonary complications, and UTI were similar between groups. MBDs were associated with developing both medical complications (OR=1.55) and surgical complications (OR=1.79), both p<0.001.
CONCLUSION(S): MBD patients have an increased risk of 2-year postop comps and reoperations following short lumbar fusion for DDD compared to patients without MBD when controlling for demographics and comorbidity profile. These data underscore the importance of preoperative screening and optimization in this patient population. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND:Although epidural steroid injection (ESI) may provide pain relief for patients with degenerative spondylolisthesis in treatment regimens of up to 4 months, it remains unclear whether ESI affects crossover from nonoperative to operative management. METHODS:This retrospective cohort study analyzed 2 groups of surgical candidates with degenerative spondylolisthesis: those who received ESI within 3 months after enrollment (ESI group) and those who did not (no-ESI group). Annual outcomes following enrollment were assessed within operative and nonoperative groups (patients who initially chose or were assigned to surgery or nonoperative treatment) by using longitudinal mixed-effect models with a random subject intercept term accounting for correlations between repeated measurements. Treatment comparisons were performed at follow-up intervals. Area-under-the-curve analysis for all time points assessed the global significance of treatment. RESULTS:The study included 192 patients in the no-ESI group and 74 in the ESI group. The no-ESI group had greater baseline Short Form-36 (SF-36) Bodily Pain scores (median, 35 versus 32) and self-reported preference for surgery (38% versus 11%). There were no differences in surgical rates within 4 years after enrollment between the no-ESI and ESI groups (61% versus 62%). The surgical ESI and no-ESI groups also showed no differences in changes in patient-reported outcomes at any follow-up interval or in the 4-year average. Compared with the nonoperative ESI group, the nonoperative no-ESI group showed greater improvements in SF-36 scores for Bodily Pain (p = 0.004) and Physical Function (p = 0.005) at 4 years, Bodily Pain at 1 year (p = 0.002) and 3 years (p = 0.005), and Physical Function at 1 year (p = 0.030) and 2 years (p = 0.002). Of the patients who were initially treated nonsurgically, those who received ESI and those who did not receive ESI did not differ with regard to surgical crossover rates. The rates of crossover to nonoperative treatment by patients who initially chose or were assigned to surgery also did not differ between the ESI and no-ESI groups. CONCLUSIONS:There was no relationship between ESI and improved clinical outcomes over a 4-year study period for patients who chose or were assigned to receive surgery for degenerative spondylolisthesis. In the nonsurgical group, ESI was associated with inferior pain reduction through 3 years, although this was confounded by greater baseline pain. ESI showed little relationship with surgical crossover. LEVEL OF EVIDENCE/METHODS:Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

BACKGROUND:Surgical site infections (SSIs) affect 1% to 9% of all spine surgeries. Though previous work has found diabetes mellitus type 2 (DM2) to increase the risk for wound infection, the influence of perioperative hyperglycemia is poorly described. OBJECTIVE:To investigate perioperative hyperglycemia as an independent risk factor for surgical site infection. METHODS:We retrospectively identified patients undergoing operative management of SSIs occurring after spinal surgery for degenerative pathologies. These patients were individually matched to controls based upon age, surgical invasiveness, ICD-10CM, race, and sex. Cases and controls were compared regarding medical comorbidities (including diabetes), postoperative hyperglycemia, and operative time. RESULTS:Patients in the infection group were found to have a higher BMI (33.7 vs 28.8), higher prevalence of DM2 (48.5% vs 14.7%), and longer inpatient stay (8.8 vs 4.3 d). They also had higher average (136.6 vs 119.6 mg/dL) and peak glucose levels (191.9 vs 153.1 mg/dL), as well as greater variability in glucose levels (92.1 vs 58.1 mg/dL). Multivariable logistic regression identified BMI (odds ratio [OR] = 1.13), diabetes mellitus (OR = 2.12), average glucose on the first postoperative day (OR = 1.24), peak postoperative glucose (OR = 1.31), and maximal daily glucose variation (OR = 1.32) as being significant independent predictors of postoperative surgical site infection. CONCLUSION/CONCLUSIONS:Postoperative hyperglycemia and poor postoperative glucose control are independent risk factors for surgical site infection following surgery for degenerative spine disease. These data suggest that, particularly among high-risk diabetic patients, strict perioperative glucose control may decrease the risk of SSI.

BACKGROUND CONTEXT/BACKGROUND:Patients with severe cervical deformity (CD) often have profound deficits in numerous activities of daily living. The association between health status and post-operative radiographic goals is difficult to quantify. PURPOSE/OBJECTIVE:We aimed to investigate the radiographic characteristics of patients who achieved optimal health related quality of life scores following surgery for CD. STUDY DESIGN/METHODS:We performed a retrospective review of a prospectively collected database of patients with spinal deformity. PATIENT SAMPLE/METHODS:One hundred and fifty-three patients with cervical deformity OUTCOME MEASURES: Common health-related quality of life scores (HRQOLs) measurements were taken for patients treated operatively for cervical deformity including neck disability index (NDI), modified Japanese Orthopaedic Association scale (mJOA) for myelopathy and numeric rating scale for neck pain (NRS-neck), METHODS: Surgical patients with severe (can you define severe?) CD were isolated based upon a previously presented discriminant analysis which outlined a combination of preoperative cervical sagittal vertical axis (cSVA), T1 slope, maximum focal kyphosis in extension, C2 slope in extension, and number of kyphotic levels in extension. Those with available preoperative and 1-year postoperative HRQL data were included. Based on a previous study, patients were grouped into 3 distinct sagittal morphotypes of CD: focal deformity (FD), flatneck (FN=large TS-CL and lack of compensation), or cervicothoracic (CT). Post-operative outcomes were defined as "good" if a patient had ≥2 of the 3 following criteria (1) NDI <20 or meeting MCID, (2) mild myelopathy (mJOA≥14), and (3) NRS-Neck ≤5 or improved by ≥2 points from baseline. Within each distinct deformity group, patients with good outcomes were compared to those with poor outcomes (i.e. not meeting the criteria for good) for differences in demographics, HRQL scores, and alignment, via Chi-squared or student's t-tests. RESULTS:Overall, 83 of 153 patients met the criteria of severe CD and 40 patients had complete 1-year follow-up of clinical/radiographic data. Patient breakdown by deformity pattern was: CT (N=13), FN (N=17), and FD (N=17), with 7 patients meeting criteria for both FD and FN deformities. Within the FD cohort, maximal focal kyphosis (i.e. kyphosis at one level) was better corrected in patients with a "good" outcome (p = 0.03). In the FN cohort, patients with "good" outcomes presented pre-operatively with worse horizontal gaze (McGregor Slope 21° vs 6°, p=0.061) and cSVA (72mm vs 60mm, p=0.030). "Good" outcome FN patients showed significantly greater postop correction of horizontal gaze (-25° vs -5°, p = 0.031). In the CT cohort, patients with "good" outcomes had superior global alignment both pre- (SVA: -17mm vs 108mm, p <0.001) and post-operatively (50mm vs 145mm, p=0.001). CT patients with "good" outcomes also had better postop cervical alignment (cSVA 35mm vs 49mm, p=0.030), and less kyphotic segments during extension (p=0.011). In the FD cohort, there were no differences between "good" and "poor" outcomes patients in preoperative alignment; however, "good" outcome patients showed superior changes in postoperative focal kyphosis (-2° vs 5°, p=0.030). Within all three deformity pattern categories, there were no differences between "good" and "poor" outcome patients with respect to demographics or surgical parameters (levels fused, surgical approach, decompression, osteotomy, all p>0.050). CONCLUSIONS:The results of this study show each CD patient's unique deformity must be carefully examined in order to determine the appropriate alignment goals to achieve optimal HRQOLs. In particular, the recognition of the sagittal morphotype can help assist surgeons to aim for specific alignment goals for CT, FN and FD. Distinct deformity specific intra-operative goals include obtaining proper sagittal global/cervical alignment for cervicothoracic patients, correcting maximal focal kyphosis in focal deformity patients, and correcting horizontal gaze for flatneck patients.