Faculty Bibliography

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.

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.

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.

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.

OBJECT/OBJECTIVE:Sexual function is an important factor which contributes to quality of life. ASD patients may have sexual limitations due to lumbar spinal stiffness which may be affected by long-segment fusion. METHODS:This study utilized a multi-center, prospectively defined, consecutive cohort of ASD patients. The primary outcome in this study was the LSDI question 10: "Choose the statement that best describes the effect of low back stiffness on your ability to engage in sexual intercourse". RESULTS:In total, 368 patients were included in this study, including 76 males and 292 females of which 80.7% (n=293) underwent 9 or more level fusion and 74.4% (n=270) had pelvic fixation. Baseline LSDI sexual function scores averaged 1.7 (SD 1.3), which improved to 1.3 (SD 1.2) at 2-year follow-up (p = 0.0008). After adjusting for confounding factors, worse LSDI sexual function score was strongly associated with worse ODI, SRS total, and SF-36 PCS and MCS scores at both baseline and 2-year follow-up (p<0.05 for all comparisons). Predictors of poorer baseline sexual function included older age, increased SVA, and increased back pain (p<0.05 for all comparisons). Predictors of improvement in sexual function at 2-year follow-up included SVA improvement (p=0.0032) and decreased postoperative back pain (p<0.0001). CONCLUSIONS:This study found that sexual dysfunction scores due to lumbar stiffness significantly improved following surgery for ASD. Additionally, lumbar stiffness related sexual dysfunction is strongly related to overall outcome measured by ODI and SRS total score, highlighting the importance of sexual health on overall outcome in ASD patients.

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.

OBJECTIVE:Although surgical treatment can provide significant improvement of symptomatic adult cervical spine deformity (ACSD), few reports have focused on the associated complications. The objective of this study was to assess complication rates at a minimum 1-year follow-up based on a prospective multicenter series of ACSD patients treated surgically. METHODS:A prospective multicenter database of consecutive operative ACSD patients was reviewed for perioperative (< 30 days), early (30-90 days), and delayed (> 90 days) complications with a minimum 1-year follow-up. Enrollment required at least 1 of the following: cervical kyphosis > 10°, cervical scoliosis > 10°, C2-7 sagittal vertical axis > 4 cm, or chin-brow vertical angle > 25°. RESULTS:Of 167 patients, 133 (80%, mean age 62 years, 62% women) had a minimum 1-year follow-up (mean 1.8 years). The most common diagnoses were degenerative (45%) and iatrogenic (17%) kyphosis. Almost 40% of patients were active or past smokers, 17% had osteoporosis, and 84% had at least 1 comorbidity. The mean baseline Neck Disability Index and modified Japanese Orthopaedic Association scores were 47 and 13.6, respectively. Surgical approaches were anterior-only (18%), posterior-only (47%), and combined (35%). A total of 132 complications were reported (54 minor and 78 major), and 74 (56%) patients had at least 1 complication. The most common complications included dysphagia (11%), distal junctional kyphosis (9%), respiratory failure (6%), deep wound infection (6%), new nerve root motor deficit (5%), and new sensory deficit (5%). A total of 4 deaths occurred that were potentially related to surgery, 2 prior to 1-year follow-up (1 cardiopulmonary and 1 due to obstructive sleep apnea and narcotic use) and 2 beyond 1-year follow-up (both cardiopulmonary and associated with revision procedures). Twenty-six reoperations were performed in 23 (17%) patients, with the most common indications of deep wound infection (n = 8), DJK (n = 7), and neurological deficit (n = 6). Although anterior-only procedures had a trend toward lower overall (42%) and major (21%) complications, rates were not significantly different from posterior-only (57% and 33%, respectively) or combined (61% and 37%, respectively) approaches (p = 0.29 and p = 0.38, respectively). CONCLUSIONS:This report provides benchmark rates for ACSD surgery complications at a minimum 1-year (mean 1.8 years) follow-up. The marked health and functional impact of ACSD, the frail population it affects, and the high rates of surgical complications necessitate a careful risk-benefit assessment when contemplating surgery. Collectively, these findings provide benchmarks for complication rates and may prove useful for patient counseling and efforts to improve the safety of care.

BACKGROUND:Frailty is a relatively new area of study for patients with cervical deformity (CD). As of yet, little is known of how operative intervention influences frailty status for patients with CD. OBJECTIVE:To investigate drivers of postoperative frailty score and variables within the cervical deformity frailty index (CD-FI) algorithm that have the greatest capacity for change following surgery. METHODS:Descriptive analysis of the cohort were performed, paired t-tests determined significant baseline to 1 yr improvements of factors comprising the CD-FI. Pearson bivariate correlations identified significant associations between postoperative changes in overall CD-FI score and CD-FI score components. Linear regression models determined the effect of successful surgical intervention on change in frailty score. RESULTS:A total of 138 patients were included with baseline frailty scores of 0.44. Following surgery, mean 1-yr frailty score was 0.27. Of the CD-FI variables, 13/40 (32.5%) were able to improve with surgery. Frailty improvement was found to significantly correlate with baseline to 1-yr change in CBV, PI-LL, PT, and SVA C7-S1. HRQL CD-FI components reading, feeling tired, feeling exhausted, and driving were the greatest drivers of change in frailty. Linear regression analysis determined successful surgical intervention and feeling exhausted to be the greatest significant predictors of postoperative change in overall frailty score. CONCLUSION/CONCLUSIONS:Complications, correction of sagittal alignment, and improving a patient's ability to read, drive, and chronic exhaustion can significantly influence postoperative frailty. This analysis is a step towards a greater understanding of the relationship between disability, frailty, and surgery in CD.