Faculty Bibliography

Introduction/UNASSIGNED:Osteotomies are commonly performed to correct sagittal malalignment in cervical deformity (CD). However, the risks and benefits of performing a major osteotomy for cervical deformity correction have been understudied. The objective of this retrospective cohort study was to investigate the risks and benefits of performing a major osteotomy for CD correction. Methods/UNASSIGNED:-tests and Chi-squared tests were used to assess differences between MAJ and MIN. A sub-analysis compared patients with flexible versus rigid CL. Results/UNASSIGNED:> 0.05). Conclusions/UNASSIGNED:Cervical deformity patients who underwent a major osteotomy had similar clinical outcomes at 3-months but worse outcomes at 1-year as compared to minor osteotomies, likely due to differences in baseline deformity. Patients with rigid deformities who underwent a major osteotomy had higher complication rates and worse clinical improvement despite similar realignment at 1 year.

Background/UNASSIGNED:For cervical deformity (CD) surgery, goals include realignment, improved patient quality of life, and improved clinical outcomes. There is limited research identifying patients most likely to achieve all three. Objective/UNASSIGNED:The objective is to create a model predicting good 1-year postoperative realignment, quality of life, and clinical outcomes following CD surgery using baseline demographic, clinical, and radiographic factors. Methods/UNASSIGNED:Retrospective review of a multicenter CD database. CD patients were defined as having one of the following radiographic criteria: Cervical sagittal vertical axis (cSVA) >4 cm, cervical kyphosis/scoliosis >10°° or chin-brow vertical angle >25°. The outcome assessed was whether a patient achieved both a good radiographic and clinical outcome. The primary analysis was stepwise regression models which generated a dataset-specific prediction model for achieving a good radiographic and clinical outcome. Model internal validation was achieved by bootstrapping and calculating the area under the curve (AUC) of the final model with 95% confidence intervals. Results/UNASSIGNED:Seventy-three CD patients were included (61.8 years, 58.9% F). The final model predicting the achievement of a good overall outcome (radiographic and clinical) yielded an AUC of 73.5% and included the following baseline demographic, clinical, and radiographic factors: mild-moderate myelopathy (Modified Japanese Orthopedic Association >12), no pedicle subtraction osteotomy, no prior cervical spine surgery, posterior lowest instrumented vertebra (LIV) at T1 or above, thoracic kyphosis >33°°, T1 slope <16 and cSVA <20 mm. Conclusions/UNASSIGNED:Achievement of a positive outcome in radiographic and clinical outcomes following surgical correction of CD can be predicted with high accuracy using a combination of demographic, clinical, radiographic, and surgical factors, with the top factors being baseline cSVA <20 mm, no prior cervical surgery, and posterior LIV at T1 or above.

STUDY DESIGN/UNASSIGNED:Comparative cohort study. OBJECTIVE/UNASSIGNED:Factors that influence the lower instrumented vertebra (LIV) selection in adult cervical deformity (ACD) are less reported, and outcomes in the cervicothoracic junction (CTJ) and proximal thoracic (PT) spine are unclear. METHODS/UNASSIGNED:A prospective ACD database was analyzed using the following inclusion criteria: LIV between C7 and T5, upper instrumented vertebra at C2, and at least a 1-year follow-up. Patients were divided into CTJ (LIV C7-T2) and PT groups (LIV T3-T5) based on LIV levels. Demographics, operative details, radiographic parameters, and the health-related quality of life (HRQOL) scores were compared. RESULTS/UNASSIGNED:= 0.001). Complications and reoperations were comparable. The HRQOL scores were not different preoperatively and at 1-year follow-up. CONCLUSIONS/UNASSIGNED:The selection of PT LIV in cervical deformities was more common in patients with larger baseline deformities, who were more likely to undergo pedicle-subtraction osteotomy. Despite this, the complications and HRQOL outcomes were comparable at 1-year follow-up.

OBJECTIVE:The goal of this study was to reliably predict sagittal and coronal spinal alignment with clinical photographs by using markers placed at easily localized anatomical landmarks. METHODS:A consecutive series of patients with adult spinal deformity were enrolled from a single center. Full-length standing radiographs were obtained at the baseline visit. Clinical photographs were taken with reflective markers placed overlying C2, S1, the greater trochanter, and each posterior-superior iliac spine. Sagittal radiographic parameters were C2 pelvic angle (CPA), T1 pelvic angle (TPA), and pelvic tilt. Coronal radiographic parameters were pelvic obliquity and T1 coronal tilt. Linear regressions were performed to evaluate the relationship between radiographic parameters and their photographic "equivalents." The data were reanalyzed after stratifying the cohort into low-body mass index (BMI) (< 30) and high-BMI (≥ 30) groups. Interobserver and intraobserver reliability was assessed for clinical measures via intraclass correlation coefficients (ICCs). RESULTS:A total of 38 patients were enrolled (mean age 61 years, mean BMI 27.4 kg/m2, 63% female). All regression models were significant, but sagittal parameters were more closely correlated to photographic parameters than coronal measurements. TPA and CPA had the strongest associations with their photographic equivalents (both r2 = 0.59, p < 0.001). Radiographic and clinical parameters tended to be more strongly correlated in the low-BMI group. Clinical measures of TPA and CPA had high intraobserver reliability (all ICC > 0.99, p < 0.001) and interobserver reliability (both ICC > 0.99, p < 0.001). CONCLUSIONS:The photographic measures of spinal deformity developed in this study were highly correlated with their radiographic counterparts and had high inter- and intraobserver reliability. Clinical photography can not only reduce radiation exposure in patients with adult spinal deformity, but also be used to assess deformity when full-spine radiographs are unavailable.

BACKGROUND:Frailty severity may be an important determinant for impaired recovery after cervical spine deformity (CD) corrective surgery. OBJECTIVE:To evaluate postop clinical recovery among CD patients between frailty states undergoing primary procedures. METHODS:Patients >18 yr old undergoing surgery for CD with health-related quality of life (HRQL) data at baseline, 3-mo, and 1-yr postoperative were identified. Patients were stratified by the modified CD frailty index scale from 0 to 1 (no frailty [NF] <0.3, mild/severe fraily [F] >0.3). Patients in NF and F groups were propensity score matched for TS-CL (T1 slope [TS] minus angle between the C2 inferior end plate and the C7 inferior end plate [CL]) to control for baseline deformity. Area under the curve was calculated for follow-up time intervals determining overall normalized, time-adjusted HRQL outcomes; Integrated Health State (IHS) was compared between NF and F groups. RESULTS:A total of 106 CD patients were included (61.7 yr, 66% F, 27.7 kg/m2)-by frailty group: 52.8% NF, 47.2% F. After propensity score matching for TS-CL (mean: 38.1°), 38 patients remained in each of the NF and F groups. IHS-adjusted HRQL outcomes from baseline to 1 yr showed a significant difference in Euro-Qol 5 Dimension scores (NF: 1.02, F: 1.07, P = .016). No significant differences were found in the IHS Neck Disability Index (NDI) and modified Japanese Orthopedic Association between frailty groups (P > .05). F patients had more postop major complications (31.3%) compared to the NF (8.9%), P = .004, though DJK occurrence and reoperation between the groups was not significant. CONCLUSION/CONCLUSIONS:While all groups exhibited improved postop disability and pain scores, frail patients experienced greater amount of improvement in overall health state compared to baseline disability. This signifies that with frailty severity, patients have more room for improvement postop compared to baseline quality of life.

STUDY DESIGN/UNASSIGNED:Retrospective chart review. OBJECTIVE/UNASSIGNED:The goal of this study is to examine the relationship between global alignment and proportion (GAP) score and postoperative orthoses with likelihood of developing proximal junctional kyphosis (PJK). METHODS/UNASSIGNED:Patients who underwent thoracic or lumbar fusions of ≥4 levels for adult spinal deformity (ASD) with 1-year post-operative alignment x-rays were included. Chart review was conducted to determine spinopelvic alignment parameters, PJK, and reoperation. RESULTS/UNASSIGNED:< .05. GAP change was not correlated with PJKA change. Postoperative orthoses were used in 46% of patients and did not impact sPJK. CONCLUSIONS/UNASSIGNED:There was no correlation between PJK and GAP or change in GAP. Greater correction of UIV-PA and larger postop T1-UIV was associated with greater PJKA change; suggesting that the greater alignment correction led to greater likelihood of failure. Postoperative orthoses had no impact on PJK.

STUDY DESIGN/METHODS:Retrospective review of a prospective multicenter cervical deformity database OBJECTIVE.: To examine the differences in sagittal alignment correction between three positioning methods in cervical spinal deformity surgery (CD). SUMMARY OF BACKGROUND DATA/BACKGROUND:Surgical correction for CD is technically demanding and various techniques are utilized to achieve sagittal alignment objectives. The effect of different patient positioning techniques on sagittal alignment correction following CD remains unknown. METHODS:Patients with sagittal deformity who underwent a posterior approach (with and without anterior approach) with an upper instrumented vertebra of C6 or above. Patients with Grade 5, 6 or 7 osteotomies were excluded. Positioning groups were Mayfield skull clamp, bivector traction, and halo ring. Pre-operative lower surgical sagittal curve (C2-C7), C2-C7 sagittal vertical axis (cSVA), cervical scoliosis, T1 slope minus cervical lordosis (TS-CL), T1 Slope (T1S), chin-brow vertebral angle (CBVA), C2-T3 curve, and C2-T3 SVA was assessed and compared to post-operative radiographs. Segmental changes were analyzed using the Fergusson method. RESULTS:80 patients (58% female) with a mean age was 60.6 ± 10.5 years (range 31-83) were included. The mean post-operative C2-C7 lordosis was 7.8°±14 and C2-C7 SVA was 34.1mm ± 15. There were overall significant changes in cervical alignment across the entire cohort, with improvements in T1 slope (p < 0.001), C2-C7 (p < 0.001), TS-CL (p < 0.001), and cSVA (p = 0.006). There was no difference post-operatively of any radiographic parameter between positioning groups (p > 0.05). The majority of segmental lordotic correction was achieved at C4-5-6 (Mean 6.9°±11). Additionally, patients who had bivector traction applied had had significantly more segmental correction at C7-T1-T2 compared to Mayfield and halo traction (4.2° vs. 0.3° vs. -1.7° respectively, p < 0.027). CONCLUSION/CONCLUSIONS:Post-operative cervical sagittal correction or alignment was not affected by patient position. The majority of segmental correction occurred at C4-5-6 across all positioning methods, while bivector traction had the largest corrective ability at the cervicothoracic junction. LEVEL OF EVIDENCE/METHODS:4.

BACKGROUND CONTEXT/BACKGROUND:Anterior Lumbar Interbody Fusion and Lateral Lumbar Interbody Fusion with percutaneous posterior screw fixation are two techniques used to address degenerative lumbar pathologies. Traditionally, these anterior-posterior (AP) surgeries involve repositioning the patient from the supine or lateral decubitus position to prone for posterior fixation. To reduce operative time (OpTime) and subsequent complications of prolonged anesthesia, single-position lumbar surgery (SPLS) is a novel, minimally invasive alternative performed entirely from the lateral decubitus position. PURPOSE/OBJECTIVE:Assess the perioperative safety and efficacy of single position AP lumbar fusion surgery (SPLS). STUDY DESIGN/METHODS:Multicenter retrospective cohort study. PATIENT SAMPLE/METHODS:Three hundred and ninety patients undergoing AP surgery were included, of which 237 underwent SPLS and 153 were in the Flip group. OUTCOME MEASURES/METHODS:Outcome measures included levels fused, percentage of cases including L5-S1 fusion, fluoroscopy radiation dosage, OpTime, estimated blood loss (EBL), length of stay (LOS), and perioperative complications. Radiographic analysis included lumbar lordosis (LL), pelvic incidence, pelvic tilt, and segmental LL. METHODS:Patients undergoing primary Anterior Lumbar Interbody Fusion and/or Lateral Lumbar Interbody Fusion surgery with bilateral percutaneous pedicle screw fixation between L2-S1 were included over a 4-year period. Patients were classified as either traditional repositioned "Flip" surgery or SPLS. Outcome measures included levels fused, percentage of cases including L5-S1 fusion, fluoroscopy radiation dosage, OpTime, EBL, LOS, perioperative complications. Radiographic analysis included LL, pelvic incidence, pelvic tilt, and segmental LL. All measures were compared using independent samples t-tests and chi-squared analyses as appropriate with significance set at p < .05. Propensity matching was completed where demographic differences were found. RESULTS:Three hundred and ninety patients undergoing AP surgery were included, of which 237 underwent SPLS and 153 were in the Flip group. Age, gender, BMI, and CCI were similar between groups. Levels fused (1.47 SPLS vs 1.52 Flip, p = .468) and percent cases including L5-S1 (31% SPLS, 35% Flip, p = .405) were similar between cohorts. SPLS significantly reduced OpTime (103 min vs 306 min, p < .001), EBL (97 vs 313 mL, p < .001), LOS (1.71 vs 4.12 days, p < .001), and fluoroscopy radiation dosage (32 vs 88 mGy, p < .001) compared to Flip. Perioperative complications were similar between cohorts with the exception of postoperative ileus, which was significantly lower in the SPLS group (0% vs 5%, p < .001). There was no significant difference in wound, vascular injury, neurological complications, or Venous Thrombotic Event. There was no significant difference found in 90-day return to operating room (OR). CONCLUSIONS:SPLS improves operative efficiency in addition to reducing blood loss, LOS and ileus in this large cohort study, while maintaining safety.

Purpose/UNASSIGNED:The aim is to investigate the relationship between cervical parameters and the modified Japanese Orthopedic Association scale (mJOA). Materials and Methods/UNASSIGNED:> 0.05), Pearson correlations were run for radiographic parameters and mJOA. For significant correlations, logistic regressions were performed to determine a threshold of radiographic measures for which the correlation with mJOA scores was most significant. mJOA score of 14 and <12 reported cut-off values for moderate (M) and severe (S) disability. New modifiers were compared to an existing classification using Spearman's rho and logistic regression analyses to predict outcomes up to 2 years. Results/UNASSIGNED:= 0.002). Compared to existing Ames- International Spine Study Group classification, the novel thresholds demonstrated significant predictive value for reoperation and mortality up to 2 years. Conclusions/UNASSIGNED:Collectively, these radiographic values can be utilized in refining existing classifications and developing collective understanding of severity and surgical targets in corrective surgery for adult CD.

BACKGROUND:Spinal surgery is associated with an inherently elevated risk profile, and thus far there has been limited discussion about how these outpatient spine patients are benefiting from these same-day procedures against other typical outpatient orthopedic surgeries. METHODS:Orthopedic patients who received either inpatient or outpatient surgery were isolated in the American College of Surgeons National Surgical Quality of Improvement Program (2005-2016). Patients were stratified by type of orthopedic surgery received (spine, knee, ankle, shoulder, or hip). Mean comparisons and chi-squared tests assessed basic demographics. Perioperative complications were analyzed via regression analyses in regard to their principal inpatient or outpatient orthopedic surgery received. RESULTS:< .05) with complications decreasing for IN and OUT patients by 2016. CONCLUSIONS:Over the past decade, spine surgery has decreased in complications for IN and OUT procedures along with IN/OUT knee, ankle, hip, and shoulder procedures, reflecting greater tolerance for risk in an outpatient setting. LEVEL OF EVIDENCE/METHODS:3. CLINICAL RELEVANCE/CONCLUSIONS:Despite the increase in riskier spine procedures, complications have decreased over the years. Surgeons should aim to continue to decrease inpatient spine complications to the level of other orthopedic surgeries.