Faculty Bibliography

BACKGROUND:Adult spinal deformity (ASD) represents a major cause of disability in the elderly population in the United States. Surgical intervention has been shown to reduce disability and pain in properly indicated patients. However, there is a small subset of patients in whom nonoperative treatment is also able to durably maintain or improve symptoms. OBJECTIVE:To examine the factors associated with successful nonoperative management in patients with ASD. METHODS:We retrospectively evaluated a cohort of 207 patients with nonoperative ASD, stratified into 3 groups: (1) success, (2) no change, and (3) failure. Success was defined as a gain in minimal clinically importance difference in both Oswestry Disability Index and Scoliosis Research Society-Pain. Logistic regression model and conditional inference decision trees established cutoffs for success according to baseline (BL) frailty and sagittal vertical axis. RESULTS:In our cohort, 44.9% of patients experienced successful nonoperative treatment, 22.7% exhibited no change, and 32.4% failed. Successful nonoperative patients at BL were significantly younger, had a lower body mass index, decreased Charlson Comorbidity Index, lower frailty scores, lower rates of hypertension, obesity, depression, and neurological dysfunction (all P < .05) and significantly higher rates of grade 0 deformity for all Schwab modifiers (all P < .05). Conditional inference decision tree analysis determined that patients with a BL ASD-frailty index ≤ 1.579 (odds ratio: 8.3 [4.0-17.5], P < .001) were significantly more likely to achieve nonoperative success. CONCLUSION:Success of nonoperative treatment was more frequent among younger patients and those with less severe deformity and frailty at BL, with BL frailty the most important determinant factor. The factors presented here may be useful in informing preoperative discussion and clinical decision-making regarding treatment strategies.

This retrospective cohort study describes adult cervical deformity(ACD) patients with Ames-ACD classification at baseline(BL) and 1-year post-operatively and assesses the relationship of improvement in Ames modifiers with clinical outcomes. Patients ≥ 18yrs with BL and post-op(1-year) radiographs were included. Patients were categorized with Ames classification by primary deformity descriptors (C = cervical; CT = cervicothoracic junction; T = thoracic; S = coronal) and alignment/myelopathy modifiers(C2-C7 Sagittal Vertical Axis[cSVA], T1 Slope-Cervical Lordosis[TS-CL], Horizontal Gaze[Horiz], mJOA). Univariate analysis evaluated demographics, clinical intervention, and Ames deformity descriptor. Patients were evaluated for radiographic improvement by Ames classification and reaching Minimal Clinically Important Differences(MCID) for mJOA, Neck Disability Index(NDI), and EuroQuol-5D(EQ5D). A total of 73 patients were categorized: C = 41(56.2%), CT = 18(24.7%), T = 9(12.3%), S = 5(6.8%). By Ames modifier 1-year improvement, 13(17.8%) improved in mJOA, 26(35.6%) in cSVA grade, 19(26.0%) in Horiz, and 15(20.5%) in TS-CL. The overall proportion of patients without severe Ames modifier grades at 1-year was as follows: 100% cSVA, 27.4% TS-CL, 67.1% Horiz, 69.9% mJOA. 1-year post-operatively, severe myelopathy(mJOA = 3) prevalence differed between Ames-ACD descriptors (C = 26.3%, CT = 15.4%, T = 0.0%, S = 0.0%, p = 0.033). Improvement in mJOA modifier correlated with reaching 1-year NDI MCID in the overall cohort (r = 0.354,p = 0.002). For C descriptors, cSVA improvement correlated with reaching 1-year NDI MCID (r = 0.387,p = 0.016). Improvement in more than one radiographic Ames modifier correlated with reaching 1-year mJOA MCID (r = 0.344,p = 0.003) and with reaching more than one MCID for mJOA, NDI, and EQ-5D (r = 0.272,p = 0.020). In conclusion, improvements in radiographic Ames modifier grades correlated with improvement in 1-year postoperative clinical outcomes. Although limited in scope, this analysis suggests the Ames-ACD classification may describe cervical deformity patients' alignment and outcomes 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/METHODS:A single-center retrospective cohort study. OBJECTIVE:The objective of this study was to assess the effects of patient height and pelvic incidence (PI) on age-adjusted alignment outcomes of surgical adult spinal deformity (ASD) patients. SUMMARY OF BACKGROUND DATA/BACKGROUND:Patient height and PI have yet to be evaluated for their individual effects on achieving age-adjusted alignment targets. METHODS:Surgical ASD patients were grouped by percentile (low: <25th; normative: 25th-75th; high: >75th) for height and PI. Correction groups were generated at postoperative follow-up for actual alignment compared with age-adjusted ideal values for pelvic tilt (PT), pelvic incidence minus lumbar lordosis mismatch (PI-LL), and sagittal vertical axis, and PI-adjusted ideal alignment values for sacral slope (SS), as derived from clinically relevant formulas. Means comparison tests assessed differences in rates of matching ideal alignment (±10 y threshold for age-adjusted targets; -7 to 5 degrees measured minus ideal for SS) across height and PI groups. RESULTS:Breakdown of all included 198 patients by PI group: low (25%, 38±11 degrees), normative (50%, 57±5 degrees), high (25%, 75±7 degrees). Breakdown of patient height groups: low (25%, 1.52±0.04 m), normative (50% 1.64±0.05 m), and high (25%, 1.79±0.06 m). Overall, 29% of patients met postoperative age-adjusted alignment targets for PT, 23% for PI-LL, and 25% for sagittal vertical axis. Overall, 26% of patients met PI-adjusted SS alignment. There were no differences across patient height groups in rates of achieving adjusted alignment target (all P>0.05). Patients with high PI reached age-adjusted ideal alignment for PT at a lower rate (16%) than patients with normative (33%) or low PI (33%, P=0.056). Of patients that matched at least 1 ideal alignment target, those with high PI showed inferior preoperative to postoperative changes in EuroQol 5-dimension questionnaire as compared with normative and low PI patients (P=0.015). CONCLUSIONS:Patients with high PI reached ideal postoperative age-adjusted PT alignment at a lower rate than patients with normative and low PI. Height had no impact on postoperative age-adjusted alignment outcomes. Current postoperative ideal alignment targets may warrant an adjustment to account for PI.

Psychiatric diagnoses (PD) present a significant burden on elective surgery patients and may have potentially dramatic impacts on outcomes. As ailments of the spine can be particularly debilitating, the effect of PD on outcomes was compared between elective spine surgery patients and other common elective orthopedic surgery procedures. This study included 412,777 elective orthopedic patients who were concurrently diagnosed with PD within the years 2005 to 2016. 30.2% of PD patients experienced a post-operative complication, compared to 25.1% for non-PD patients (p < 0.001). Mood Disorders (bipolar or depressive disorders) were the most commonly diagnosed PD for all elective Orthopedic procedures, followed by anxiety, then dementia (p < 0.001). Logistic regression analysis found PD to be a significant predictor of higher cost to charge ratio (CCR), length of stay (LOS), and death (all p < 0.001). Between, hand, elbow, and shoulder specialties, spine patients had the highest odds of increased CCR and unfavorable discharge, and the second highest odds of death (all p < 0.001).

Background/UNASSIGNED:Age-adjusted alignment targets in the context of distal junctional kyphosis (DJK) development have yet to be investigated. Our aim was to assess age-adjusted alignment targets, reciprocal changes, and role of lowest instrumented level orientation in DJK development in cervical deformity (CD) patients. Methods/UNASSIGNED:CD patients were evaluated based on lowest fused level: cervical (C7 or above), upper thoracic (UT: T1-T6), and lower thoracic (LT: T7-T12). Age-adjusted alignment targets were calculated using published formulas for sagittal vertical axis (SVA), pelvic incidence-lumbar lordosis (PI-LL), pelvic tilt (PT), T1 pelvic angle (TPA), and LL-thoracic kyphosis (TK). Outcome measures were cervical and global alignment parameters: Cervical SVA (cSVA), cervical lordosis, C2 slope, C2-T3 angle, C2-T3 SVA, TS-CL, PI-LL, PT, and SVA. Subanalysis matched baseline PI to assess age-adjusted alignment between DJK and non-DJK. Results/UNASSIGNED:< 0.05). The distribution of over/under corrected patients and the offset between actual and ideal alignment for SVA, PT, TPA, PI-LL, and LL-TK were similar between DJK and non-DJK patients. DJK patients requiring reoperation had worse postoperative changes in all cervical parameters and trended toward larger offsets for global parameters. Conclusion/UNASSIGNED:CD patients with severe baseline malalignment went on to develop postoperative DJK. Age-adjusted alignment targets did not capture differences in these populations, suggesting the need for cervical-specific goals.

BACKGROUND:In the setting of congenital C1 occipitalization and C2-3 fusion, significant strain is placed on the atlantoaxial joint. Vertebral fusion both above and below the atlantoaxial joint (i.e., a "sandwich") creates substantial instability. We retrospectively report on a case series of "sandwich fusion" atlantoaxial dislocation (AAD), describing the associated clinical characteristics and detailing surgical treatment. To the best of our knowledge, the present study is the largest investigation to date of this congenital subgroup of AAD. METHODS:Seventy consecutive patients with sandwich fusion AAD, from one senior surgeon, were retrospectively reviewed. The clinical features and the surgical treatment results were assessed using descriptive statistics. No funding sources or potential conflict of interest-associated biases exist. RESULTS:The mean patient age was 42.2 years (range: 5-77 years); 36 patients were male, and 34 were female. Fifty-eight patients (82.9%) had myelopathy, with Japanese Orthopaedic Association (JOA) scores ranging 4-16 (mean: 12.9). Cranial neuropathy was involved in 10 cases (14.3%). The most common presentation age group was 31 to 40 years (24 cases, 34.3%). Radiological findings revealed brainstem and/or cervical-medullar compression (58 cases, 82.9%), syringomyelia (16 cases, 22.9%), Chiari malformation (12 cases, 17.1%), cervical spinal stenosis (10 cases, 14.3%), high scapula deformity (1 case, 1.4%), os odontoideum (1 case, 1.4%), and dysplasia of the atlas (1 case, 1.4%). Computed tomography angiography was performed in 27 cases, and vertebral artery (VA) anomalies were identified in 14 cases (51.9%). All 70 patients underwent surgical treatment, without spinal cord or VA injury. Four patients (5.7%) suffered complications, including 1 wound infection, 1 screw loosening, and 2 cases of bulbar paralysis. In the 58 patients with myelopathy, the mean JOA score increased from 12.9 to 14.5. The average follow-up time was 50.5 months (range: 24-120 months). All 70 cases achieved solid atlantoaxial fusion at the final follow-up. CONCLUSIONS:Sandwich fusion AAD, a unique subgroup of AAD, has distinctive clinical features and associated malformations such as cervical-medullar compression, syringomyelia, and VA anomalies. Surgical treatment of AAD was associated with myelopathy improvement and minimal complication occurrence.

BACKGROUND CONTEXT: The impact of neuromuscular disorders such as multiple sclerosis (MS) on outcomes following anterior cervical discectomy and fusion (ACDF) is underreported. PURPOSE: Identify the impact of MS on two-year (2Y) postoperative complications and revisions following 2-3-level ACDF for cervical radiculopathy (CR) or myelopathy (CM). STUDY DESIGN/SETTING: Retrospective review of the New York State Statewide Planning and Research Cooperative System (SPARCS) database. PATIENT SAMPLE: Patients undergoing 2-3 level ACDF for CR/CM. OUTCOME MEASURES: Two-year postoperative complications and reoperations.
METHOD(S): Patients undergoing 2-3 level ACDF for CR/CM were identified from SPARCS. Patients with a baseline diagnosis of MS were also identified. Patients with infectious/traumatic/neoplastic were excluded. The remaining patients were 1:1 propensity score-matched (MS to no-MS) for age, sex, race, Deyo index and compared for rates of 2Y postoperative complications and reoperations. Logistic regression models were utilized to determine significant predictors of these outcomes.
RESULT(S): A total of 302 total patients were identified (MS, n=151; non-MS, n=151). MS patients were more frequently female (72.8% vs 27.2%, p<0.001). Age was comparable (50.1 vs 50.1 years, p=0.225). MS patients incurred higher charges for their surgical visit ($41,029 vs $31,654) and higher LOS (2.8 vs 2.2 days), both p<=0.016. They experienced higher rates of deep vein thrombosis (DVT) (3.3% vs 0%, p=0.02), with similar overall medical (19.2% vs 21.2%), surgical (7.9% vs 10.6%), and total complications (21.9% vs 25.8%), all p>0.05. MS patients had similar rates of 2Y revisions (6.6% vs 5.3%, p=0.627). MS was not associated with medical, surgical, or overall complications or revisions at minimum 2Y follow-up.
CONCLUSION(S): Despite differences in demographics and higher rates of postoperative DVT, MS patients experienced comparable postoperative course with respect to other individual and overall complications and revisions following 2-3-level CF for degenerative spinal pathologies. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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PURPOSE/OBJECTIVE:Tethered cord syndrome (TCS) is an occult spinal dysraphism that includes low lying conus, tight filum terminale, lipomeningomyelocele, split cord malformations, dermal sinus tracts, and dermoids. This congenital disorder has been associated with musculoskeletal, neurological, and gastrointestinal abnormalities. This study presents a retrospective review of the prospectively collected data of TCS patients and their concurrent diagnoses or associated anomalies. METHODS:The National Inpatient Sample (NIS) database from 2003 to 2012 was used for data collection. Hospital- and year-adjusted weights allowed for accurate assessment of the incidence of TCS, as well as cardiac and gastrointestinal (GI) and genitourinary (GU) anomalies. K-means clustering analysis was run to discover patterns of concurrent cardiac, GI, GU, and other system anomalies in TCS patients. RESULTS:A total of 13,470 discharges with a diagnosis of TCS were identified in the NIS database, and at least one additional anomaly was identified in 40.7% of TCS patients. The most common secondary anomalies by system were: spine (24.48%), cardiac (6.27%), and urinary (5.37%). For patients with multiple anomalies, the most common combinations were GI and cardiac (4.55%), urinary and GI (4.26%), and urinary and cardiac (4.19%). The most common spinal association was spina bifida (13.65%). The most common neurological or musculoskeletal anomaly was any VACTERL association (13.45%). The top relation in GI and GU anomalies was cervix and female genitalia anomalies (69.1%). The most common specific anomalies were spina bifida, large intestine atresia, Rubenstein-Taybi syndrome, and atrial and ventral septal defects. CONCLUSION/CONCLUSIONS:This study provides a nationwide prospective on congenital anomalies and concurrent conditions present in tethered cord syndrome patients in the United States and demonstrates that 40.7% of TCS patients have at least one associated anomaly. The most common congenital anomalies studied were spina bifida, urogenital with or without cardiac septal defects, and cystourethral anomaly or cystic kidney disease with or without large intestinal atresia.

BACKGROUND CONTEXT: MBDs are often implicated in or contribute to degenerative disc disease (DDD). Yet, there is limited long-term, postoperative outcome data on the impact of MBDs on 2-year outcomes following 2-3-level lumbar fusion for DDD. PURPOSE: To determine if DDD patients with MBDs have comparable outcomes to those without MBDs following lumbar fusion. STUDY DESIGN/SETTING: Retrospective cohort. PATIENT SAMPLE: New York State Statewide Planning and Research Cooperative System was reviewed from 2009-2013 to identify all patients with DDD who underwent short, lumbar fusion (2-3-levels) with >=2-year follow-up OUTCOME MEASURES: Two-year outcome rates (medical/surgical complications and reoperations).
METHOD(S): The New York State Statewide Planning and Research Cooperative System was reviewed from 2009-2013 to identify all patients with DDD who underwent short, lumbar fusion (2-3 levels) with >=2-year follow-up. Patients with and without MBD (vitamin D deficiency, hyperparathyroidism, osteomalacia, and rickets) were identified. Any patients with osteoporosis or other systemic/endocrine disorders affecting bone quality were excluded. Traumatic, infectious, and neoplastic surgical indications were excluded. Cohorts were compared for demographics and 2-year outcome rates (medical/surgical complications and reoperations). Logistic regression was used to identify covariates associated with medical/surgical complications and revisions.
RESULT(S): A total of 28,959 patients were included (MBD, n=380 (1.33%); no-MBD, n=28,579). MBD pts were older (56.4 vs 53.1 years) and more often female (65.5% vs 49.80%) than no-MBD pts (all p<0.001). MBD pts had longer hospital stays (4.57 days vs 4.11 days, p=0.026), but charges were similar. MBD pts incurred higher rates of wound complications (11.8% vs 6.0%), acute renal failure (11.1% vs 4.7%), pneumonia (9.2% vs 4.4%), and implant related complications (12.1% vs 7.0%); all p<0.001. Rates of pseudarthrosis, PE, pulmonary complications, and UTI were similar between groups. MBDs were associated with developing both medical complications (OR=1.55) and surgical complications (OR=1.79), both p<0.001.
CONCLUSION(S): MBD patients have an increased risk of 2-year postop comps and reoperations following short lumbar fusion for DDD compared to patients without MBD when controlling for demographics and comorbidity profile. These data underscore the importance of preoperative screening and optimization in this patient population. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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