Faculty Bibliography

STUDY DESIGN:Retrospective review of a prospectively collected database. OBJECTIVES:This preliminary investigation sought to identify the quality of care adolescent idiopathic scoliosis (AIS) patients from our large, underserved community had received before presenting at this institution's clinic. SUMMARY OF BACKGROUND DATA:AIS affects 1% to 4% of children between ages 10 and 16. Barriers to health care for patients in underserved populations have not been well studied. METHODS:Patients who visited a single surgeon's clinic for primary AIS between June 2016 and January 2017 were enrolled. Patients had 36-inch full-spine radiographs and completed a survey of demographics, prior AIS care received (screening, bracing, etc), socioeconomic parameters, and patient-reported outcomes (PROs; Scoliosis Research Society [SRS]-30 Questionnaire and Body Image Disturbance Questionnaire [BIDQ]). Parametric and nonparametric analyses were used and percentages and mean/median values were reported. RESULTS:47 patients (age: 15 ± 3 years; 82.7% female) were included. Overall, 25.5% of patients reported a family history of scoliosis, and 42.6% had no prior knowledge of scoliosis. Per Scoliosis Research Society (SRS) recommendations, 15 patients required observation (main Cobb angle: <25°), 22 patients were eligible for bracing (25°-45°), and 10 patients were surgical candidates (>45°). In addition, 21.3% of all patients were never screened for scoliosis; of these, 50% had a main scoliosis curve >25°. Seventy percent of surgical candidates never wore a brace, and 59.3% of screened patients who were eligible for bracing were not braced at initial presentation. Patients who were left unbraced when eligible exhibited worse BIDQ scores (1.7 vs. 1.4, p < .05). CONCLUSIONS:One of five children in our population was never screened for scoliosis, and nearly three of five children did not receive optimal care as recommended by SRS. AIS patients in our inner-city populations are potentially at risk of continuing to experience a significant disadvantage in health care access. LEVEL OF EVIDENCE:Level IV case series.

STUDY DESIGN/METHODS:Retrospective cohort study. OBJECTIVE:The goals of this study were to (1) evaluate pre-operative bone quality assessment and intervention practice over time and (2) review the current evidence for bone evaluation in spine fusion surgery. SUMMARY OF BACKGROUND DATA/BACKGROUND:Deformity spine surgery has demonstrated improved quality of life in patients however its cost has made it controversial. If pre-operative bone quality can be optimized then potentially these treatments could be more durable however, at present, no clinical practice guidelines have been published by professional spine surgical organizations. METHODS:A retrospective cohort review was performed on patients who underwent a minimum five-level primary or revision fusion. Pre-operative bone quality metrics were evaluated over time from 2012 - 2017 to find potential trends. Sub-group analysis was conducted based on age, gender, pre-operative diagnosis, and spine fusion region. RESULTS:Patient characteristics including pre-operative rates of pseudarthrosis and junctional failure did not change. An increasing trend of physician bone health documentation was noted (p = 0.045) but changes in other metrics were not significant. A gender bias favored females who had higher rates of pre-operative DXA studies (p = 0.001), Vitamin D 25-OH serum labs (p = 0.005), Vitamin D supplementation (p = 0.022), calcium supplementation (p < 0.001), antiresorptive therapy (p = 0.016), and surgeon clinical documentation of bone health (p = 0.008) compared to men. CONCLUSION/CONCLUSIONS:Our spine surgeons have increased documentation of bone health discussions but this has not affected bone quality interventions. A discrepancy exists favoring females over males in nearly all pre-operative bone quality assessment metrics. Pre-operative vitamin D level and BMD assessment should be considered in patients undergoing long fusion constructs however the data for bone anabolic and resorptive agents has less support. Clinical practice guidelines on pre-operative bone quality assessment spine patients should be defined. LEVEL OF EVIDENCE/METHODS:4.

Background/UNASSIGNED:Given the paucity of literature regarding compensatory mechanisms used by obese patients with sagittal malalignment, it is necessary to gain a better understanding of the effects of obesity on compensation after comparing the degree of malalignment to age-adjusted ideals. This study aims to compare baseline alignment of obese and nonobese patients using age-adjusted spino-pelvic alignment parameters, describing associated spinal changes. Methods/UNASSIGNED:tests compared parameters between cohorts. Results/UNASSIGNED: < .001) compared to nonobese patients with PI-LL larger than age-adjusted ideal. Conclusions/UNASSIGNED:Regardless of malalignment severity, obese patients recruited lower-limb compensation more than nonobese patients. Obese patients with PI-LL mismatch larger than age-adjusted ideal also develop upper-cervical and cervicothoracic compensation for malalignment. Level of Evidence/UNASSIGNED:III. Clinical Relevance/UNASSIGNED:Clinical evaluation should extend to the cervical spine in obese patients not meeting age-adjusted sagittal alignment ideals.

Background/UNASSIGNED:The study aims to evaluate differences in alignment and clinical outcomes between surgical cervical deformity (CD) patients with a subaxial upper-most instrumented vertebra (UIV) and patients with a UIV at C2. Use of CD-corrective instrumentation in the subaxial cervical spine is considered risky due to narrow subaxial pedicles and vertebral artery anatomy. While C2 fixation provides increased stability, the literature lacks guidelines indicating extension of CD-corrective fusion from the subaxial spine to C2. Methods/UNASSIGNED:Included: operative CD patients with baseline (BL) and 1-year postop (1Y) radiographic data, cervical UIV ≥ C2. Patients were grouped by UIV: C2 or subaxial (C3-C7) and propensity score matched (PSM) for BL cSVA. Mean comparison tests assessed differences in BL and 1Y patient-related, radiographic, and surgical data between UIV groups, and BL-1Y changes in alignment and clinical outcomes. Results/UNASSIGNED:. 6.2°). Between UIV groups, there were no differences in BL-1Y changes in HRQLs, overall complication rates, or operative complication rates (all P>0.05). Conclusions/UNASSIGNED:C2 UIV patients showed similar cervical range of motion and baseline to 1-year functional outcomes as patients with a subaxial UIV. C2 UIV patients also showed greater baseline to 1-year horizontal gaze improvement and had complication profiles similar to subaxial UIV patients, demonstrating the radiographic benefit and minimal functional loss associated with extending fusion constructs to C2. In the treatment of adult cervical deformities, extension of the reconstruction construct to the axis may allow for certain clinical benefits with less morbidity than previously acknowledged.

Introduction/UNASSIGNED:The aim of this study was to evaluate the association of available cervical alignment components through the Ames cervical deformity (CD) classification parameters with the Patient-Reported Outcomes Measurement Information System (PROMIS) physical health domain metrics. Methods/UNASSIGNED:Surgical CD patients (C2-C7 Cobb >10° or C2-C7 sagittal vertical axis [cSVA] >4 cm or T1 slope minus cervical lordosis (TS-CL) >15°) ≥18 years with available baseline (BL) radiographic and PROMIS were isolated in a single-center spine database. Patients were classified according to the Ames CD modifiers for cSVA and TS-CL (low deformity [Low], moderate deformity [Mod], and severe deformity [Sev]). Descriptives and univariate analyses compared population-weighted PROMIS scores for Pain Intensity (PI), Physical Function (PF), and Pain Interference (Int) across CD modifiers. Conditional tree analysis with logistic regression sampling determined the threshold of PROMIS scores for which the correlation with Ames radiographic cutoffs was most significant. Reported cutoff values for Mod (cSVA: 4-8 cm; TS-CL: 15-20°) and Sev (cSVA: >8 cm; TS-CL: >20°) disabilities were used. Results/UNASSIGNED:, Charlson Comorbidity Index: 1.19). BL cSVA modifier by severity: 83.2% Low, 16.8% Mod. No patients met criteria for severe cSVA. BL TS-CL modifier by severity: 18.8% Low, 22.1% Mod, 59.1% Sev. Mean baseline PROMIS scores were as follows: PI score: 89.6 ± 15.4, PF score: 11.9 ± 13.1, Int score: 56.9 ± 6.8. PI did not differ between cSVA and TS-CL severity. Mod cSVA patients and Mod/Sev TS-CL modifier groups trended toward lower PF scores and higher Int scores. A PI score of >96 (odds ratio [OR]: 0.658 [0.303-1.430]), a PF score of <14 (OR: 1.864 [0.767-4.531]), and an Int score of > 57.4 (OR: 1.878 [0.889-3.967]) were predictors of Mod cSVA. A PI score of >87 (OR: 1.428 [0.767-2.659]), a PF score of <14 (OR: 1.551 [0.851-2.827]), and an Int score of >56.5 (OR: 1.689 [0.967-2.949]) were predictors of Sev TS-CL. Conclusions/UNASSIGNED:PROMIS physical health domains were related to the Ames CD classification. Certain BL PROMIS thresholds can be connected to the severity of CD.

Introduction/UNASSIGNED:Correction of cervical deformity (CD) often involves different types of osteotomies to address sagittal malalignment. This study assessed the relationship between osteotomy grade and vertebral level on alignment and clinical outcomes. Methods/UNASSIGNED:Retrospective review of a multi-center prospectively collected CD database. CD was defined as at least one of the following: C2-C7 Cobb >10°, cervical lordosis (CL) >10°, C2-C7 sagittal vertical axis (cSVA) >4 cm, and chin-brow vertical angle > 25°. Patients were evaluated for level and type of cervical osteotomy. Results/UNASSIGNED:= 0.058) due to lever arm effect. Conclusions/UNASSIGNED:CD patients undergoing osteotomies in the cervical and upper thoracic spine experienced improvement in TS--CL and C2 slope. In the upper thoracic spine, multiple minor osteotomies achieved similar alignment changes to major osteotomies at a single level, while a major osteotomy focused at T2 had the greatest overall impact in cervicothoracic and global alignment in CD patients.

Hypothesis/UNASSIGNED:Reciprocal changes in the upper cervical spine correlate with adult TL deformity modifiers. Design/UNASSIGNED:This was a retrospective review. Introduction/UNASSIGNED:The upper cervical spine has remarkable adaptability to wide ranges of thoracolumbar (TL) deformity. Methods/UNASSIGNED:assessed changes in BL upper cervical parameters (C0-2, C0 slope, McGregor's Slope [MGS], and CBVA) across groups. Results/UNASSIGNED:< 0.001). Conclusions/UNASSIGNED:Our study suggests that upper cervical alignment remains relatively stable through most broad variations of adult TL deformity. Changes in SVA correlated most with upper cervical changes.

Background/UNASSIGNED:Klippel-Feil syndrome (KFS) includes craniocervical anomalies, low posterior hairline, and brevicollis, with limited cervical range of motion; however, there remains no consensus on inheritance pattern. This study defines incidence, characterizes concurrent diagnoses, and examines trends in the presentation and management of KFS. Methods/UNASSIGNED:This was a retrospective review of the Kid's Inpatient Database (KID) for KFSpatients aged 0-20 years from 2003 to 2012. Incidence was established using KID-supplied year and hospital-trend weights. Demographics and secondary diagnoses associated with KFS were evaluated. Comorbidities, anomalies, and procedure type trends from 2003 to 2012 were assessed for likelihood to increase among the years studied using ANOVA tests. Results/UNASSIGNED:Eight hundred and fifty-eight KFS diagnoses (age: 9.49 years; 51.1% females) and 475 patients with congenital fusion (CF) (age: 8.33 years; 50.3% females) were analyzed. We identified an incidence rate of 1/21,587 discharges. Only 6.36% of KFS patients were diagnosed with Sprengel's deformity; 1.44% with congenital fusion. About 19.1% of KFS patients presented with another spinal abnormality and 34.0% presented with another neuromuscular anomaly. About 36.51% of KFS patients were diagnosed with a nonspinal or nonmusculoskeletal anomaly, with the most prevalent anomalies being of cardiac origin (12.95%). About 7.34% of KFS patients underwent anterior fusions, whereas 6.64% of KFS patients underwent posterior fusions. The average number of levels operated on was 4.99 with 8.28% receiving decompressions. Interbody devices were used in 2.45% of cases. The rate of fusions with <3 levels (7.46%) was comparable to that of 3 levels or greater (7.81%). Conclusions/UNASSIGNED:KFS patients were more likely to have other spinal abnormalities (19.1%) and nonnervous system abnormalities (13.63%). Compared to congenital fusions, KFS patients were more likely to have congenital abnormalities such as Sprengel's deformity. KFS patients are increasingly being treated with spinal fusion. Level of Evidence/UNASSIGNED:III.

OBJECTIVEProximal junctional kyphosis (PJK) is a structural complication of spinal fusion in 5%-61% of patients treated for adult spinal deformity. In nearly one-third of these cases, PJK is progressive and requires costly surgical revision. Previous studies have suggested that patient body habitus may predict risk for PJK. Here, the authors sought to investigate abdominal girth and paraspinal muscle size as risk factors for PJK.METHODSAll patients undergoing thoracolumbosacral fusion greater than 2 levels at a single institution over a 5-year period with ≥ 6 months of radiographic follow-up were considered for inclusion. PJK was defined as kyphosis ≥ 20° between the upper instrumented vertebra (UIV) and two supra-adjacent vertebrae. Operative and radiographic parameters were recorded, including pre- and postoperative sagittal vertical axis (SVA), sacral slope (SS), lumbar lordosis (LL), pelvic tilt, pelvic incidence (PI), and absolute value of the pelvic incidence-lumbar lordosis mismatch (|PI-LL|), as well as changes in LL, |PI-LL|, and SVA. The authors also considered relative abdominal girth and the size of the paraspinal muscles at the UIV.RESULTSOne hundred sixty-nine patients met inclusion criteria. On univariate analysis, PJK was associated with a larger preoperative SVA (p < 0.001) and |PI-LL| (p = 0.01), and smaller SS (p = 0.004) and LL (p = 0.001). PJK was also associated with more positive postoperative SVA (p = 0.01), ΔSVA (p = 0.01), Δ|PI-LL| (p < 0.001), and ΔLL (p < 0.001); longer construct length (p = 0.005); larger abdominal girth-to-muscle ratio (p = 0.007); and smaller paraspinal muscles at the UIV (p < 0.001). Higher postoperative SVA (OR 1.1 per cm), smaller paraspinal muscles at the UIV (OR 2.11), and more aggressive reduction in |PI-LL| (OR 1.03) were independent predictors of radiographic PJK on multivariate logistic regression.CONCLUSIONSA more positive postoperative global sagittal alignment and smaller paraspinal musculature at the UIV most strongly predicted PJK following thoracolumbosacral fusion.

STUDY DESIGN/METHODS:Retrospective cohort study at a single institution. OBJECTIVE:To analyze the perioperative and postoperative outcomes of patients who underwent open transforaminal lumbar interbody fusion (O-TLIF) and bilateral minimally invasive (MIS) Wiltse approach TLIF (Wil-TLIF). SUMMARY OF BACKGROUND DATA/BACKGROUND:Several studies have compared Open TLIF to MIS TLIF, however, comparing the techniques using a large cohort of one-level TLIFs has not been fully explored. METHODS:We reviewed the charts of patients undergoing a single-level primary posterior lumbar interbody fusion between 2012 and 2017. The cases were categorized as Open TLIF (traditional midline exposure including lateral exposure of transverse processes) or bilateral paramedian Wiltse TLIF approach. Differences between groups were assessed by t-tests. RESULTS:227 patients underwent one-level primary TLIF (116 O-TLIF, 111 Wil-TLIF). There was no difference in age, gender, ASA or BMI between groups. Wil-TLIF had the lowest EBL (197 mL vs. 499 mL O-TLIF, p =  < .001), LOS (2.7 days vs. 3.6 days O-TLIF, p =  < .001), overall complication rate (12% vs. 24% O-TLIF, p = .015), minor complication rate (7% vs. 16% O-TLIF, p = .049), and 90-day readmission rate (1% vs. 8% O-TLIF, p = .012). Wil-TLIF was associated with the higher fluoroscopy time (83 sec vs. vs. 24 sec O-TLIF, p =  < .001). There was not a significant difference in operative time, intraoperative or neurological complications, extubation time, reoperation rate, or infection rate. CONCLUSIONS:In comparing Wiltse MIS TLIF to Open TLIF, the minimally invasive paramedian Wiltse approach demonstrated the lowest EBL, LOS, readmission rates and complications, but longer fluoroscopy times when compared to the traditional open approach. LEVEL OF EVIDENCE/METHODS:3.