Faculty Bibliography

BACKGROUND CONTEXT: Age and pelvic incidence (PI) optimal alignment has been shown to minimize mechanical complications such as PJK. Low PI patients may be susceptible to overcorrection because PI specific alignment is not always prioritized. PURPOSE: The purpose of this study is to examine the incidence of over-correction in low PI ASD patients undergoing surgical intervention, and to quantify the impact of over-correction on radiographic PJK in this patient population. STUDY DESIGN/SETTING: Retrospective analysis of a prospective, multicenter database. PATIENT SAMPLE: Surgical ASD patients with low pelvic incidence. OUTCOME MEASURES: PJK defined as 1) proximal junctional angle (PJA, U

BACKGROUND CONTEXT: Frailty is an increasingly recognized characteristic that has been validated across many studies as influencing operative risk. Utilization of frailty indices can allow for its identification of which spine patients may be too high risk for surgical intervention. This may be especially useful when it comes to surgeries that are minimally invasive and are supposed to have decrease perioperative outcomes. PURPOSE: Identify MIS techniques effects in postoperative outcomes in TLIF patients. STUDY DESIGN/SETTING: Retrospective review of a prospective database. PATIENT SAMPLE: TLIF spine patients. OUTCOME MEASURES: Complications, length of stay (LOS), estimated blood loss (EBL).
METHOD(S): Pts that underwent a lumbar spine procedure in a single-center Comprehensive Spine Quality Database. Pts were stratified based on procedural approach (Open [OP] and Minimally invasive Surgery [MIS]). Frailty was then calculated for each resultant group by using 30 variables with a validated method. Based on these scores, pts were categorized no frailty [NF]: <0.09, frail [F]: 0.09-0.18, and severe frailty [SF] >0.18. Groups were then controlled for surgical invasiveness. Chi-squared tests identified the relationship between complications and length of stay among various frailty states given surgical approach (OP vs MIS). These patients were propensity score matched for levels fused. Hospital acquired complications (HACs) were identified based on frailty groups through the use of chi-squared and t-tests for other surgical factors. A logistic regression analysis identified the association between frailty status and surgical, regarding postoperative (postop) outcomes.
RESULT(S): A total of 1,300 TLIF spine patients were isolated (59yrs, 29.3kg/m2). After PSM for levels fused, there were 338 pts for both MIS and OP. MIS pts were older (56.1 vs 53.3; p<0.05) than Op pts and had similar BMI's (29.1 vs 29.7; respectively). However, OP received more posterior approaches and less anterior approaches than MIS pts (p<0.05). By surgical factors: MIS and OP patients had similar LOS (3 vs 2.9days) and EBL (282.8 vs 251.5cc) but differed by Op time (195.7 vs 247.1; p<0.05) respectively. Further breakdown by frailty displayed statistical significance between MIS and OP patients with MIS pts having more F (16% vs 12%) and SF pts (4.3% vs 1.9%) than OP (all p<0.05). FMIS patients had lower postop neurologic complications as compared to FOP pts (4.63% vs 14.8%). However, SFMIS patiens had more post-operative complications than SFOP pts (55.2% vs 23.1%) and increased a pt's likelihood of being SFMIS by 5.4x's (all p<0.05).
CONCLUSION(S): This study displays that when frailty status is taken into account, TLIF MIS patients benefit from this procedure type when analyzed against neurologic complications. However, these patients were seen to suffer more from postop complications but did not differ on any other specific complications or surgical variables. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Operative treatment of adult spinal deformity (ASD) can be very challenging with high complication rates. Despite these challenges it's well established that pts benefit from such treatment. However, the surgical outcomes for pts with mild scoliosis and age appropriate sagittal alignment have not been reported. PURPOSE: To determine if patients (pts) with mild scoliosis and age appropriate sagittal alignment have favorable outcomes following surgical correction. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter ASD database. PATIENT SAMPLE: ASD patients: operative pts age>=18, and all preoperartive pelvic tilt (PT), mismatch between pelvic incidence and lumbar lordosis (PI-LL), and C7 sagittal vertical axis (SVA) within established age adjusted parameters with minimum 2-year follow up. A subanalysis for pts with max coronal cobb angle 10-30degree (mild scoli) was done. OUTCOME MEASURES: Health-related quality of life (HRQOL) scores: Oswestry Disability Index (ODI), Short form-36(SF36), Scoliosis Research Society (SRS22), back/leg pain numerical rating scale (NRS) and minimum clinically important difference (MCID)/substantial clinical benefit (SCB). Radiographic values: max coronal cobb angle, coronal C7 plumb line, PT, PI-LL, thoracic kyphosis (TK), SVA. Demographic, frailty, surgical and complications data were collected.
METHOD(S): Two-year and baseline HRQOL/radiographic data were compared.
RESULT(S): A total of 103 pts were included from 667 operative patients (89.3% female, avg age 59.8+/-13.1yrs). Of the 103 pts, 29 (28.2%) had max preop coronal cobb angle 10-30degree. Two-year max coronal cobb angle and C7 coronal plumb were significantly improved compared to baseline (p<0.001 for both the overall cohort and mild scoli). All 2yr HRQOL measures were significantly improved compared to baseline(p<0.001) for both groups. 33.3-81.5%% of mild scoli pts met either MCID/SCB for all HRQOL. In mild scoli pts, 62.1% had min one complication, 27.6% had a major complication with 24.1% requiring a revision.
CONCLUSION(S): Pts with mild scoliosis and sagittal alignment within age appropriate parameters benefit from surgical correction at 2 years postop both radiographically and clinically including 81.5% meeting MCID for SRS pain despite having high complication rates. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Substantial adult spinal deformity (ASD) research has focused on sagittal plane radiological assessment and emphasized the importance of sagittal correction on patient-reported outcomes. It seems less attention has been given to evaluation of ASD in the coronal plane. However, recent ASD studies have demonstrated baseline global coronal malalignment (GCM; substantial displacement of the C7 coronal plumb line from midsacrum) in up to 35% of patients. Moreover, GCM can worsen postoperatively or may occur as an iatrogenic complication in previously balanced patients. Collectively, this may suggest that the associated clinical impact of GCM on ASD surgical outcomes has been underestimated. Currently, few reports focus on surgical outcomes in ASD patients with GCM. PURPOSE: Our objective was to assess treatment outcomes and complication rates associated with ASD surgery in the subset of patients with severe GCM. STUDY DESIGN/SETTING: Retrospective review of a prospectively collected multicenter consecutive case registry. PATIENT SAMPLE: Enrollment required: age >=18 years, scoliosis >=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree, and/or thoracic kyphosis >=60degree. OUTCOME MEASURES: Radiographic correction (both standard coronal and sagittal spinopelvic deformity measurements) and health-related quality of life (HRQL) outcomes, which included Oswestry Disability Index (ODI), Short Form-36 (SF-36) scores, Scoliosis Research Society-22 (SRS-22) scores, and back/leg pain numerical rating scale (NRS) scores.
METHOD(S): Surgically treated ASD patients with severe GCM (coronal C7PL-midsacral offset magnitude >=1 SD above the mean) were identified. Baseline and follow-up radiographic and HRQL outcomes were analyzed. Percentages of patients achieving minimal clinically important difference (MCID) and substantial clinical benefit (SCB) were assessed. Demographic, frailty, surgical, and complications data were collected. The primary focus for analysis was on patients who reached minimum 2-year follow-up.
RESULT(S): Of 691 potentially eligible operative patients (mean GCM = 4+/-3 cm), 80 met criteria for severe GCM >= 7cm. Of these 80 patients, 62 (78%, mean age 64 years, 81% women) had minimum 2-year follow-up. Baseline frailty score was 3.9+/-1.5 (indicating patients were frail) and 48% had prior spine fusion. Surgical data included: posterior-only (58%), mean fusion 13 levels, sacroiliac fixation (97%), and three-column osteotomy (36%). Postoperative biplane alignment improved significantly (p<0.001): GCM 11 to 4 cm, lumbar Cobb 30degree to 11degree, C7-S1 SVA 13 to 4 cm, and PI-LL 31degree to 5degree. Overall HRQL improved significantly (p<=0.003): ODI 51 to 37, SF-36 PCS 29 to 37, SRS-22r 2.6 to 3.5, and back/leg pain NRS 7 to 4 and 5 to 3, respectively. Thresholds for MCID/SCB were met in 43-83% of patients. A total of 89 complications were reported (34 minor/55 major), and 45 (73%) patients had >=1 complication (most commonly rod fracture [19%] and PJK [18%]). There were 34 reoperations in 22 (36%) patients (most common indications rod fracture/PJK). The 18 patients who did not achieve 2-year follow-up had a mean of 0.63 years follow-up, and the types of complications encountered in these 18 patients were comparable to those encountered in patients with 2-year follow-up.
CONCLUSION(S): ASD surgery for patients with severe GCM is associated with significant improvements in biplane alignment and HRQL outcome measures despite high complication rates. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND:As of May 4, 2020, the coronavirus disease 2019 (COVID-19) pandemic has affected >3.5 million people and touched every inhabited continent. Accordingly, it has stressed health systems worldwide, leading to the cancellation of elective surgical cases and discussions regarding health care resource rationing. It is expected that rationing of surgical resources will continue even after the pandemic peak and may recur with future pandemics, creating a need for a means of triaging patients for emergent and elective spine surgery. METHODS:Using a modified Delphi technique, a cohort of 16 fellowship-trained spine surgeons from 10 academic medical centers constructed a scoring system for the triage and prioritization of emergent and elective spine surgeries. Three separate rounds of videoconferencing and written correspondence were used to reach a final scoring system. Sixteen test cases were used to optimize the scoring system so that it could categorize cases as requiring emergent, urgent, high-priority elective, or low-priority elective scheduling. RESULTS:The devised scoring system included 8 independent components: neurologic status, underlying spine stability, presentation of a high-risk postoperative complication, patient medical comorbidities, expected hospital course, expected discharge disposition, facility resource limitations, and local disease burden. The resultant calculator was deployed as a freely available Web-based calculator (https://jhuspine3.shinyapps.io/SpineUrgencyCalculator/). CONCLUSIONS:We present the first quantitative urgency scoring system for the triage and prioritizing of spine surgery cases in resource-limited settings. We believe that our scoring system, although not all encompassing, has potential value as a guide for triaging spine surgical cases during the COVID pandemic and post-COVID period.

STUDY DESIGN/UNASSIGNED:Retrospective cohort study of prospective patients undergoing minimally invasive lumbar fusion at a single academic institution. OBJECTIVE/UNASSIGNED:To assess differences in perioperative outcomes between primary and revision MIS (minimally invasive surgical) lumbar interbody fusion patients and compare with those undergoing corresponding open procedures. METHODS/UNASSIGNED:Patients ≥18 years old undergoing lumbar interbody fusion were grouped by surgical technique: MIS or open. Patients within each group were propensity score matched for comorbidities and levels fused. Patient demographics, surgical factors, and perioperative complication incidences were compared between primary and revision cases using means comparison tests, as appropriate. RESULTS/UNASSIGNED:< .05). CONCLUSIONS/UNASSIGNED:Clinical outcomes of revision MIS lumbar interbody fusion were similar to those of primary surgery. Additionally, MIS techniques were associated with less EBL, shorter LOS, and fewer perioperative complications than corresponding open revisions.

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.

STUDY DESIGN/UNASSIGNED:Single-center retrospective review. OBJECTIVES/UNASSIGNED:The cervicothoracic junction (CTJ) is typically difficult to visualize using traditional radiographs. Whole-body stereoradiography (EOS) allows for imaging of the entire axial skeleton in a weightbearing position without parallax error and with lower radiation doses. In this study we sought to compare the visibility of the vertebra of the CTJ on lateral EOS images to that of conventional cervical lateral radiographs. METHODS/UNASSIGNED:Two fellowship-trained spine surgeons evaluated the images of 50 patients who had both lateral cervical radiographs and EOS images acquired within a 12-month period. The number of visible cortices of the vertebral bodies of C6-T2 were scored 0-4. Patient body mass index and the presence of spondylolisthesis >2 mm at each level was recorded. The incidence of insufficient visibility to detect spondylolisthesis at each level was also calculated for both modalities. RESULTS/UNASSIGNED:On average, there were more visible cortices with EOS versus XR at T1 and T2, whereas visible cortices were equal at C6 and C7. Patient body mass index was inversely correlated with cortical visibility on XR at T2 and on EOS at T1 and T2. There was a significant difference in the incidence of insufficient visibility to detect spondylolisthesis on EOS versus XR at C7-T1 and T1-2, but not at C6-7. CONCLUSIONS/UNASSIGNED:EOS imaging is superior at imaging the vertebra of the CTJ. EOS imaging deserves further consideration as a diagnostic tool in the evaluation of patients with cervical deformity given its ability to produce high-quality images of the CTJ with less radiation exposure.

OBJECTIVE:Our aim was to define a treatment strategy for patients with severe cervical deformity(sCD). METHODS:Surgical patients with sCD were isolated based on preop radiographic parameters. We sent 10 sCD cases to 7 surgeons to find consensus on approach, upper instrumented vertebrae (UIV), lower instrumented vertebrae (LIV), osteotomy. We performed a descriptive analysis and created a treatment algorithm from the survey then analyzed a database of surgical patients to find the frequency of following our algorithm. RESULTS:We found consensus on 7 cases for posterior approach due to cervicothoracic deformity and of 15 patients within our sCD database that had cervicothoracic deformity, 13/15 had posterior approach. There was consensus on 2 cases for antero-posterior approach due to local kyphosis and of 25 patients that had local kyphosis, 18/25 had an anterior approach. In 4 cases there was consensus of UIV of C2 and of 35 cases that had posterior fusion >6 levels, 20/35 had a UIV of C2. In 3 cases there was consensus of a LIV below a previously fused spine. Of 36 patients that had a fusion of T6 or higher, 34 had a LIV below the previous UIV. In 6 cases there was consensus against an osteotomy due to cervical spine flexibility and 9/12 patients that had an osteotomy in our database had no flexibility on dynamic radiographs. CONCLUSION/CONCLUSIONS:We outline here an algorithm for deciding approach, UIV, LIV and whether to do an osteotomy for patients with sCD based on consensus recommendations amongst spine surgeons.

OBJECT/OBJECTIVE:This case series examined patients undergoing caudal extension of prior fusion without alteration of the prior UIV to assess patient outcomes and rates of PJK/PJF. METHODS:Patients eligible for 2-year minimum follow-up undergoing caudal extension of prior fusion with unchanged UIVs were identified. These patients were evaluated for PJK/PJF, and patient reported outcomes were recorded. RESULTS:In total, 40 patients were included. Mean follow-up duration was 2.2 years (SD 0.3). Patients in this cohort had poor preoperative sagittal alignment (PI-LL 26.7°, TPA 29.0°, SVA 93.4mm) and achieved substantial sagittal correction (ΔSVA -62.2mm, ΔPI-LL -19.8°, ΔTPA -11.1°) following caudal extension surgery. At final follow-up, there was a 0% rate of PJF among patients undergoing caudal extension of previous fusion without creation of a new UIV, but 27.5% of patients experienced PJK. Patients experienced significant improvement in both ODI and SRS-22r total score at 2-years post-operatively (p<0.05). In total, 7.5% (n=3) of patients underwent further revision, at an average of 1.1 years (SD 0.54) after the surgery with unaltered UIV. All three of these patients underwent revision for rod fracture with no revisions for PJK/PJF. CONCLUSIONS:Patients undergoing caudal extension of previous fusions for sagittal alignment correction have high rates of clinical success, low revision surgery rates, and very low rates of PJF. Minimizing repetitive tissue trauma at the UIV may result in decreased PJF risk, as the PJF rate in this cohort of unaltered UIV patients is below historical PJF rates of patients undergoing sagittal balance correction.