Faculty Bibliography

BACKGROUND:Patients undergoing multilevel spine surgery are at risk for delayed extubation. OBJECTIVE:To evaluate the impact of type and volume of intraoperative fluids administered during multilevel thoracic and/or lumbar spine surgery on postoperative extubation status. METHODS:Retrospective evaluation of medical records of patients ≥ 18 yr undergoing ≥ 4 levels of thoracic and/or lumbar spine fusions was performed. Patients were organized according to postoperative extubation status: immediate (IMEX; in OR/PACU) or delayed (DEX; outside OR/PACU). Propensity score matched (PSM) analysis was performed to compare IMEX and DEX groups. Volume, proportion, and ratios of intraoperative fluids administered were evaluated for the associated impact on extubation status. RESULTS:A total of 246 patients (198 IMEX, 48 DEX) were included. PSM analysis demonstrated that increased administration of non-cell saver blood products (NCSB) and increased ratio of crystalloid: colloids infused were independently associated with delayed extubation. With increasing EBL, IMEX had a proportionate reduction in crystalloid infusion (R = -0.5, P < .001), while the proportion of crystalloids infused remained relatively unchanged for DEX (R = -0.27; P = .06). Twenty-six percent of patients receiving crystalloid: colloid ratio > 3:1 had DEX compared to none of those receiving crystalloid: colloid ratio ≤ 3:1 (P = .009). DEX had greater cardiac and pulmonary complications, surgical site infections and prolonged intensive care unit and hospital stay (P < .05). CONCLUSION/CONCLUSIONS:PSM analysis of patients undergoing multilevel thoracic and/or lumbar spine fusion demonstrated that increased administration of crystalloid to colloid ratio is independently associated with delayed extubation. With increasing EBL, a proportionate reduction of crystalloids facilitates early extubation.

AIMS/OBJECTIVE:This aim of this study was to assess the feasibility of designing and introducing generic 3D-printed instrumentation for routine use in total knee arthroplasty. MATERIALS AND METHODS/METHODS:Instruments were designed to take advantage of 3D-printing technology, particularly ensuring that all parts were pre-assembled, to theoretically reduce the time and skill required during surgery. Concerning functionality, ranges of resection angle and distance were restricted within a safe zone, while accommodating either mechanical or anatomical alignment goals. To identify the most suitable biocompatible materials, typical instrument shapes and mating parts, such as dovetails and screws, were designed and produced. RESULTS:Before and after steam sterilization, dimensional analysis showed that acrylonitrile butadiene styrene could not withstand the temperatures without dimensional changes. Oscillating saw tests with slotted cutting blocks produced debris, fractures, or further dimensional changes in the shape of Nylon-12 and polymethylmethacrylate (MED610), but polyetherimide ULTEM 1010 was least affected. CONCLUSION/CONCLUSIONS:2019;101-B(7 Supple C):115-120.

There remains confusion in the literature with regard to the spinopelvic relationship, and its contribution to ideal acetabular component position. Critical assessment of the literature has been limited by use of conflicting terminology and definitions of new concepts that further confuse the topic. In 2017, the concept of a Hip-Spine Workgroup was created with the first meeting held at the American Academy of Orthopedic Surgeons Annual Meeting in 2018. The goal of this workgroup was to first help standardize terminology across the literature so that as a topic, multiple groups could produce literature that is immediately understandable and applicable. This consensus review from the Hip-Spine Workgroup aims to simplify the spinopelvic relationship, offer hip surgeons a concise summary of available literature, and select common terminology approved by both hip surgeons and spine surgeons for future research. Cite this article: Bone Joint J 2019;101-B:808-816.

AIMS/OBJECTIVE:While previously underappreciated, factors related to the spine contribute substantially to the risk of dislocation following total hip arthroplasty (THA). These factors must be taken into consideration during preoperative planning for revision THA due to recurrent instability. We developed a protocol to assess the functional position of the spine, the significance of these findings, and how to address different pathologies at the time of revision THA. PATIENTS AND METHODS/METHODS:Prospectively collected data on 111 patients undergoing revision THA for recurrent instability from January 2014 to January 2017 at two institutions were included (protocol group) and matched 1:1 to 111 revisions specifically performed for instability not using this protocol (control group). Mean follow-up was 2.8 years. Protocol patients underwent standardized preoperative imaging including supine and standing anteroposterior (AP) pelvis and lateral radiographs. Each case was scored according to the Hip-Spine Classification in Revision THA. RESULTS:84% in the control group (18 patients). Furthermore, 77% of the inappropriately positioned acetabular components would have been unrecognized by supine AP pelvis imaging alone. CONCLUSION/CONCLUSIONS:2019;101-B:817-823.

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.

STUDY DESIGN/METHODS:Retrospective cohort study. OBJECTIVE:The objective of this study was to examine associations of gabapentin use with inpatient postoperative daily pain scores and opioid use in children undergoing PSF for AIS. SUMMARY OF BACKGROUND DATA/BACKGROUND:Gabapentin use in posterior spinal fusion (PSF) postoperative pain management for adolescent idiopathic scoliosis (AIS) is increasingly common in order to decrease opioid use and improve pain control, though there is conflicting data on dosing and effectiveness to support this practice in real world settings. METHODS:Retrospective cohort study of children aged 10 to 21 years undergoing PSF for AIS between January 2013 and June 2016 at an urban academic tertiary care center. Adjuvant gabapentin exposure was defined as at least 15 mg/kg/d by postoperative day (POD) 1 with an initial loading dose of 10 mg/kg on day of surgery. Primary outcomes were daily postoperative mean pain score and opioid use [morphine milligram equivalents/kg/day(mme/kg/d)]. Secondary outcomes were short and long-term complications. RESULTS:Among 129 subjects (mean age, 14.6 y, 74% female, mean coronal cobb, 55.2 degrees), 24 (19%) received gabapentin. Unadjusted GABA exposure was associated with significantly lower opioid use on POD1 and 2 (49% and 31%mme/kg/d, respectively) and lower pain scores (14%) on POD2. Adjusting for preexisting back pain, preoperative coronal Cobb angle, and site, GABA use was associated with significantly lower mean pain scores on POD1 through POD3 (-0.68, P=0.01; -0.86, P=0.002; -0.63, P=0.04). Gabapentin use was also associated with decreased opioid use on POD1 and POD2 (-0.39mme/kg/d, P<0.001; -0.27, P=0.02). There was no difference in complications by gabapentin exposure. CONCLUSIONS:Addition of gabapentin as adjuvant therapy for adolescent PSF, beginning on day of surgery, is associated with improved pain scores and decreased opioid use in the first 48 to 72 hours postoperatively. LEVEL OF EVIDENCE/METHODS:This is a retrospective cohort study, classified as Level III under "Therapeutic Studies Investigating the Results of a Treatment."

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.

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.

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.

The Press Ganey survey is the most widely used instrument for measuring patient satisfaction. Understanding the factors that influence these surveys may permit better use of survey results and may direct interventions to increase patient satisfaction. Press Ganey Clinician and Group Consumer Assessment of Healthcare Providers and Systems surveys administered to ambulatory spine surgery clinic patients within a large tertiary care network from May 2016 to September 2017 were retrospectively reviewed. Mean comparison testing was performed to measure associations between patient demographics and responses to "overall provider rating" and "recommend this provider's office" survey questions. Mean difference to achieve significance was set at α<0.05. A multivariate analysis was performed to determine independent factors. A total of 1400 survey responses from the offices of 11 orthopedic spine surgeons were included. Patients 18 to 34 years old had significantly lower responses to the overall provider rating question than older patients (P<.001), and increasing patient age was correlated with improved ratings. Highest education level was inversely correlated with satisfaction scores, with patients who had attained graduate level education having the lowest satisfaction scores (P=.001). Those with commercial insurance had significantly lower ratings for recommend this provider's office (P=.042) and overall provider rating (P=.022) questions than those with other insurance types. Patients administered the survey on paper had significantly lower ratings than those administered the survey online (P=.006). Provider ratings were significantly higher when the sex and ethnicity of the patient were concordant with the provider (P=.021). This study showed that independent, nonmodifiable factors such as age, education level, and survey mode were significantly associated with the satisfaction of ambulatory spine surgery clinic patients. [Orthopedics. 2019; 42(3):143-148.].