Faculty Bibliography

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.

In the current value-based healthcare climate where spine surgery is shifting to the ambulatory setting, factors influencing postop length of stay (LOS) are important to surgeons and hospital administrators. Pre-op patient factors including diagnosis of radiculopathy and myelopathy have yet to be investigated in this context. Operative pts ≥ 18Y with primary diagnoses of cervical myelopathy (M), radiculopathy (R), or myeloradiculopathy (MR) were included and propensity score matched by invasiveness score (Mirza et al.). Top-quartile LOS was defined as extended. M&R patients were compared using Chi² & independent t-tests. Univariate tests assessed differences in preop patient and surgical data in M&R pts and extended/non-extended LOS. Stepwise regression analysis explored factors predictive of LOS. 718 operative pts (54.5 yrs, 41.1%F, 29.1 kg/m², mean CCI 1.11) included (177 M, 383 R, and 158 MR). After PSM, 345 patients remained (115 in each diagnosis). 102 patients had E-LOS (Avg: 5.96 days), 41 M patients (mean 7.1 days), 28 R (5.9 days), and 33 MR (4.6 days). Regression showed predictors of E-LOS in R pts (R²â€¯= 0.532, p = 0.043): TS-CL, combined and posterior approach, LIV, UIV, op time, Lactated Ringer's, postoperative complications. Predictors of E-LOS in M pts (R²â€¯= 0.230, p < 0.001): age, CCI, combined and posterior approach, levels fused, UIV, EBL, neuro and any postop complications. Predictors of E-LOS in MR patients (R²â€¯= 0.152, p < 0.001): age, kyphosis, combined approach, UIV, LIV, levels fused, EBL and op time. Independent of invasiveness, patients with a primary diagnosis of myelopathy, though older aged and higher comorbidity profile, had consistently longer overall postop LOS when compared to radiculopathy or myeloradiculopathy patients.

BACKGROUND CONTEXT/BACKGROUND:ASD (Adult spinal deformity) surgery often entails complex osteotomies and realignment procedures, particularly in the setting of rigid deformities. While previous studies have established the efficacy of tranexamic acid (TXA), data evaluating the widely variable dosing regimens remains sparse. PURPOSE/OBJECTIVE:To improve understanding of blood loss and transfusion requirements for low-dose and high-dose TXA regimens for adult spinal deformity (ASD) surgery. STUDY DESIGN/SETTING/METHODS:This is a retrospective cohort study of 318 ASD patients who received TXA. Outcome measures include estimated blood loss (EBL), perioperative transfusion requirement, and complications. METHODS:A retrospective review was conducted on 318 ASD patients: 258 patients received a low-dose regimen of TXA (10 or 20 mg/kg loading dose with a 1 or 2 mg/kg/h maintenance dose) and 60 patients received a high-dose regimen of TXA (40 mg/kg loading dose with a 1 mg/kg/h maintenance dose, 30 mg/kg loading dose with a 10 mg/kg/h maintenance dose, or 50 mg/kg loading dose with a 5 mg/kg/h maintenance dose). RESULTS:Compared with the low-dose TXA group, the high-dose TXA group had significantly decreased EBL (1402 vs. 1793 mL, p=0.009), blood volume lost (30.3 vs. 39.4%, p=0.01), intraoperative packed red blood cell (pRBC) transfusion (0.9 vs 1.6 U, p<0.0001), and intraoperative platelet transfusion (0 versus 0.1 U, p<0.0001). High-dose TXA was predictive of 515 cc less EBL (p=0.002), 11.4% less blood volume lost (p=0.004), and 1 U pRBC less transfused intraoperatively (p<0.0001) than the low-dose TXA group. The high-dose TXA group had a higher incidence of postop atrial fibrillation (AF) (5 vs 0%, p<0.0001) and myocardial infarction (MI) (1.7 vs. 0%, p=0.04). CONCLUSIONS:Varying dosing regimens of TXA are utilized for ASD surgery, with a prevailing theme of dosing ambiguity. These data demonstrate that high-dose TXA is more effective than low-dose TXA in reducing blood loss and blood product transfusion requirement in ASD surgery. Importantly, rates of MI and postop AF were higher in the high-dose TXA group.

MINI: 172 patients underwent a primary TLIF. Those receiving <250 total MME (44%) as an inpatient had a 3.73 (odds ratio) times smaller probability of requiring opioids at 6 month follow-up. Patients who received >500 total MME (27%) had a 4.84 times greater probability of requiring opioids at 6 month follow-up.

BACKGROUND CONTEXT/BACKGROUND:Chin-Brow Vertical Angle (CBVA) is not routinely measured on radiographs even though it is a strong assessor of horizontal gaze. STUDY DESIGN/METHODS:Retrospective cohort study of patients with full-body stereoradiographs and a primary cervical diagnosis at the time of presentation. PURPOSE/OBJECTIVE:Assess the utility of McGregor's Slope (McGS) and Slope of Line of Sight (SLS) as surrogate markers for the CBVA in cervical spine pathology METHODS: A retrospective review of patients with full-body stereoradiographs was performed. Patients were ≥18 years of age with a primary cervical diagnosis. Analysis of CBVA, McGS, and SLS was conducted as markers of horizontal gaze. Sagittal alignment was characterized by: pelvic tilt (PT), pelvic incidence minus lumbar lordosis (PI-LL), T1-pelvic angle (TPA), sagittal vertical axis (SVA), T2-T12 thoracic kyphosis, C2-C7 SVA (cSVA), C2-C7 Cervical lordosis, T1-Slope minus Cervical Lordosis (TS-CL), and C2-Slope (C2S). A subgroup analysis was performed in patients with cervical deformity (CD). Independent samples t-tests and paired t-tests compared radiographic alignment. Pearson correlations characterized linear relationships. Linear regression analysis identified relationships between the parameters. RESULTS:In all, 329 patients were identified with primary cervical spine diagnoses. CBVA was visible in 171 patients (52.0%), McGS in 281 (85.4%) and SLS in 259 (78.7%). Of the 171 patients with visible CBVA, the mean CBVA was 2.30± 7.7, mean McGS was 5.02±8.1 and mean SLS was -1.588±2.03. CBVA strongly correlated with McGS (r=0.83) and SLS (r=0.89) with p<0.001. McGS positively correlated with SLS (r = 0.89, p=0.001). CONCLUSIONS:This study demonstrates that McGS and SLS serve as strong, positive correlates for CBVA. The reported mean differences between these measurements provide a useful conversion, broadening CBVA's use as a radiographic assessment of horizontal gaze.

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.].

Background/UNASSIGNED:Full-body stereographs for adult spinal deformity (ASD) have enhanced global deformity and lower-limb compensation associations. The advent of age-adjusted goals for classic ASD parameters (sagittal vertical axis, pelvic tilt, spino-pelvic mismatch [PI-LL]) has enabled individualized evaluation of successful versus failed realignment, though these remain to be radiographically assessed postoperatively. This study analyzes pre- and postoperative sagittal alignment to quantify patient-specific correction against age-adjusted goals, and presents differences in compensation in patients whose postoperative profile deviates from targets. Methods/UNASSIGNED:tests. Results/UNASSIGNED: < .001). Conclusions/UNASSIGNED:Global alignment cohort improvements were observed, and when comparing actual to age-adjusted alignment, undercorrections recruited pelvic and lower-limb flexion to compensate. Level of Evidence/UNASSIGNED:3.

MINI: The ability of PROMIS to capture disability from cervical sagittal malalignment is unknown. Correlations between PROMIS domains and legacy outcome metrics with cervical sagittal alignment parameters were analyzed. PROMIS domains correlated strongly with legacy outcomes and PROMIS Pain Intensity correlated with worsening sagittal alignment in patients with cervical sagittal deformity.

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.