Faculty Bibliography

STUDY DESIGN/METHODS:Retrospective review of prospectively collected data. OBJECTIVE:To assess the clinical impact and economic burden of the three most common hospital-acquired conditions (HACs) that occur within 30-day postoperatively for all spine surgeries and to compare these rates with other common surgical procedures. SUMMARY OF BACKGROUND DATA/BACKGROUND:HACs are part of a non-payment policy by the Centers for Medicare and Medicaid Services and thus prompt hospitals to improve patient outcomes and safety. METHODS:Patients more than 18 years who underwent elective spine surgery were identified in American College of Surgeons' National Surgical Quality Improvement Program (ACS-NSQIP) database from 2005 to 2013. Primary outcomes were cost associated with the occurrence of three most common HACs. Cost associated with HAC occurrence derived from the PearlDiver database. RESULTS:Ninety thousand five hundred fifty one elective spine surgery patients were identified, where 3021 (3.3%) developed at least one HAC. Surgical site infection (SSI) was the most common HAC (1.4%), then urinary tract infection (UTI) (1.3%) and venous thromboembolism (VTE) (0.8%). Length of stay (LOS) was longer for patients who experienced a HAC (5.1 vs. 3.2 d, P < 0.001). When adjusted for age, sex, and Charlson Comorbidity Index, LOS was 1.48 ± 0.04 days longer (P < 0.001) and payments were $8893 ± $148 greater (P < 0.001) for patients with at least one HAC. With the exception of craniotomy, patients undergoing common procedures with HAC had increased LOS and higher payments (P < 0.001). Adjusted additional LOS was 0.44 ± 0.02 and 0.38 ± 0.03 days for total knee arthroplasty and total hip arthroplasty, and payments were $1974 and $1882 greater. HACs following hip fracture repair were associated with 1.30 ± 0.11 days LOS and $4842 in payments (P < 0.001). Compared with elective spine surgery, only bariatric and cardiothoracic surgery demonstrated greater adjusted additional payments for patients with at least one HAC ($9975 and $10,868, respectively). CONCLUSION/CONCLUSIONS:HACs in elective spine surgery are associated with a substantial cost burden to the health care system. When adjusted for demographic factors and comorbidities, average LOS is 1.48 days longer and episode payments are $8893 greater for patients who experience at least one HAC compared with those who do not. LEVEL OF EVIDENCE/METHODS:3.

STUDY DESIGN/METHODS:Retrospective analysis. OBJECTIVE:To improve understanding of the impact of comorbid mental health disorders (MHDs) on long-term outcomes following cervical spinal fusion in cervical radiculopathy (CR) or cervical myelopathy (CM) patients. SUMMARY OF BACKGROUND DATA/BACKGROUND:Subsets of patients with CR and CM have MHDs, and their impact on surgical complications is poorly understood. METHODS:Patients admitted from 2009 to 2013 with CR or CM diagnoses who underwent cervical surgery with minimum 2-year surveillance were retrospectively reviewed using New York State's Statewide Planning and Research Cooperative System. Patients with a comorbid MHD were compared against those without (no-MHD). Univariate analysis compared demographics, complications, readmissions, and revisions between MHD and no-MHD cohorts. Multivariate binary logistic regression models identified independent predictors of outcomes (covariates: age, sex, Charlson/Deyo score, and surgical approach). RESULTS:A total of 20,342 patients (MHD: n = 4819; no-MHD: n = 15,523) were included. MHDs identified: depressive (57.8%), anxiety (28.1%), sleep (25.2%), and stress (2.9%). CR patients had greater prevalence of comorbid MHD than CM patients (P = 0.015). Two years postoperatively, all patients with MHD had significantly higher rates of complications (specifically: device-related, infection), readmission for any indication, and revision surgery (all P < 0.05); regression modeling corroborated these findings and revealed combined surgical approach as the strongest predictor for any complication (CR, odds ratio [OR]: 3.945, P < 0.001; CM, OR: 2.828, P < 0.001) and MHD as the strongest predictor for future revision (CR, OR: 1.269, P = 0.001; CM, OR: 1.248, P = 0.008) in both CR and CM cohorts. CONCLUSION/CONCLUSIONS:Nearly 25% of patients admitted for CR and CM carried comorbid MHD and experienced greater rates of any complication, readmission, or revision, at minimum, 2 years after cervical spine surgery. Results must be confirmed with retrospective studies utilizing larger national databases and with prospective cohort studies. Patient counseling and psychological screening/support are recommended to complement surgical treatment. LEVEL OF EVIDENCE/METHODS:3.

BACKGROUND CONTEXT/BACKGROUND:With advances in the understanding of adult spinal deformity (ASD), more complex osteotomy and fusion techniques are being implemented with increasing frequency. Patients undergoing ASD corrections infrequently require extended acute care, longer inpatient stays, and are discharged to supervised care. Given the necessity of value-based health care, identification of clinical indicators for adverse discharge disposition in ASD surgeries is paramount. PURPOSE/OBJECTIVE:On nationwide and surgeon-created databases, identify predictors of adverse discharge disposition after ASD surgeries and view corresponding differences in charges. STUDY DESIGN/SETTING/METHODS:Retrospective analysis of patients on the National Surgical Quality Improvement Program (NSQIP) database and cost data from Medicare PearlDiver Database. PATIENT SAMPLE/METHODS:Patients undergoing thoracolumbar surgery for correction of ASD. OUTCOME MEASURES/METHODS:Primary: Discharge disposition home vs. not home. Secondary: Cost differences across discharge groups. METHODS:Patients on NSQIP undergoing thoracolumbar ASD-corrective surgery with a primary diagnosis of scoliosis (ICD-9 code 737.x), and over the age of 18 were isolated. Predictors (demographic, clinical, and complications) of not-home (NH; rehab or skilled nursing facility) discharge were analyzed using binary logistic regression controlling for levels fused, decompressions, osteotomies, and revisions. Average 30-day and 90-day costs of care were reported in home, rehab, and skilled nursing facility discharge groups in patients undergoing 8+ level thoracolumbar fusion. RESULTS:1,978 patients undergoing lumbar ASD-corrective surgery were included for analysis (average age: 59.3 years, sex: 64% female). Average length of stay was 6.58 days. Upon multivariate regression analysis, age over 60 years (OR: 0.28 CI: 0.22-0.34) and female sex (p=0.003) were independent predictors of adverse discharge status. Partially dependent pre-operational functional status, defined as reliance on another person to complete some activities of daily living, increased likelihood of adverse discharge disposition (OR:0.57 CI:0.35-0.90). Despite controlling for all clinical variables except for the ones specific to each analysis, Smith-Petersen osteotomy (OR:0.51 CI:0.40-0.64), interbody device placement (OR:0.80 CI:0.64-0.98) and fixation to the iliac (OR:0.54 CI:0.41-0.70) both increased likelihood of adverse discharge. Complications most associated with adverse discharge were UTIs (OR:0.34 CI:0.21-0.57) and blood transfusions (OR:0.42 CI:0.34-0.52). Relative to home-discharge, 30-day costs of care were +$21,061 more expensive in rehab discharges, but not different in skilled nursing facility discharges (+$5,791, p=0.177). 90-day costs of care were $23,815 in rehab discharges (p<0.001), but again not different in skilled nursing facility discharges (+$6,091, p=0.212). CONCLUSIONS:Discharge destination to rehabilitation has a significant impact on cost of thoracolumbar adult spinal deformity surgeries. Patient selection can predict patients at higher risk for discharges to rehab or skilled nursing facility.

CD development secondary to PJK was recently documented in adult spinal deformity patients after surgical correction for thoracolumbar ASD. This study analyzes surgical management of patients with CD secondary to proximal junctional kyphosis (PJK) versus patients with primary CD. Retrospective review of multicenter cervical deformity (CD) database. CD defined as at least one of the following: C2-C7 coronal Cobb > 10°, cervical lordosis (CL) > 10°, cervical sagittal vertical axis (cSVA) > 4cm, CBVA > 25°. Patients were grouped into those with PJK (UIV +2 < -10°) prior to cervical surgery versus who don't (Non-PJK). Independent t-tests and chi-squared tests compared radiographic, clinical, and surgical metrics between PJK and non-PJK groups. Of 123 eligible CD patients, 26(21.1%) had radiographic PJK prior to cervical surgery. PJK patients had significantly greater T2-T12 thoracic kyphosis (-58.8° vs -45.0°, p = 0.002), cSVA (49.1 mm vs 38.9 mm, p = 0.020), T1 Slope (42.6° vs 28.4°, p < 0.001), TS-CL (44.1° vs 35.6°, p = 0.048), C2-T3 SVA (98.8 mm vs 75.8 mm, p = 0.015), C2 Slope (45.4° vs 36.0°, p = 0.043), and CTPA (6.4° vs 4.6°, p = 0.005). Comparing their surgeries, the PJK group had significantly more levels fused (10.7 vs 7.4, p = 0.01). There was significantly greater blood loss in PJK patients (1158 ± 1063vs 738 ± 793 cc, p = 0.028); operative time, surgical approach, and BMP-2 use were similar (all p > 0.05). PJK patients experienced higher rates of complications 30 and 90 days post-operatively (23.1% vs. 5.2%, p = 0.004; 30.8% vs. 19.6%, p = 0.026), and more instrumentation failure 30 days postoperatively (7.8% vs. 1.0%, p = 0.004). Patients with cervical deformity secondary to PJK had worse baseline CD, despite no differences in HRQL or demographics. Surgical correction of CD associated with PJK required more invasive surgery and had higher complication rates than non-PJK patients, despite achieving similar clinical outcomes.

STUDY DESIGN/METHODS:Retrospective analysis OBJECTIVE.: To compare long-term outcomes between patients with and without mental health comorbidities who are undergoing surgery for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA/BACKGROUND:Recent literature reveals that one in three patients admitted for surgical treatment for ASD has comorbid mental health disorder. Currently, impacts of baseline mental health status on long-term outcomes following ASD surgery have not been thoroughly investigated. METHODS:Patients admitted from 2009-2013 with diagnoses of ASD who underwent ≥4-level thoracolumbar fusion with minimum two-year follow-up were retrospectively reviewed using New York State's Statewide Planning and Research Cooperative System (SPARCS). Patients were stratified by fusion length (Short: 4-8-level; Long: ≥9 level). Patients with comorbid mental health disorder (MHD) at time of admission were selected for analysis (MHD) and compared against those without MHD (no-MHD). Univariate analysis compared demographics, complications, readmissions and revisions between cohorts for each fusion length. Multivariate binary logistic regression models identified independent predictors of outcomes (covariates: fusion length, age, female gender, and Deyo score). RESULTS:6,020 patients (MHD: n = 1,631; no-MHD: n = 4,389) met inclusion criteria. Mental health diagnoses included disorders of depression (59.0%), sleep (28.0%), anxiety (24.0%), and stress (2.3%). At two-year follow-up, MHD patients with short fusion had significantly higher complication rates (p = 0.001). MHD patients with short or long fusion also had significantly higher rates of any readmission and revision (all p ≤ 0.002). Regression modeling revealed that comorbid MHD was a significant predictor of any complication (OR: 1.17, p = 0.01) and readmission (OR: 1.32, p < 0.001). MHD was the strongest predictor of any revision (OR: 1.56, p < 0.001). Long fusion most strongly predicted any complication (OR: 1.87, p < 0.001). CONCLUSIONS:ASD patients with comorbid depressive, sleep, anxiety, and stress disorders were more likely to experience surgical complications and revision at minimum of two years following spinal fusion surgery. Proper patient counseling and psychological screening/support is recommended to complement ASD treatment. LEVEL OF EVIDENCE/METHODS:3.

BACKGROUND CONTEXT/BACKGROUND:Cost-utility analysis, a special case of cost-effectiveness analysis, estimates the ratio between the cost of an intervention to the benefit it produces in number of quality-adjusted life years. Cervical deformity correction has not been evaluated in terms of cost-utility and in the context of value-based health care. Our objective, therefore, was to determine the cost-utility ratio of cervical deformity correction. STUDY DESIGN/METHODS:This is a retrospective review of a prospective, multicenter cervical deformity database. Patients with 1-year follow-up after surgical correction for cervical deformity were included. Cervical deformity was defined as the presence of at least one of the following: kyphosis (C2-C7 Cobb angle >10°), cervical scoliosis (coronal Cobb angle >10°), positive cervical sagittal malalignment (C2-C7 sagittal vertical axis >4 cm or T1-C6 >10°), or horizontal gaze impairment (chin-brow vertical angle >25°). Quality-adjusted life years were calculated by both EuroQol 5D (EQ5D) quality of life and Neck Disability Index (NDI) mapped to short form six dimensions (SF6D) index. Costs were assigned using Medicare 1-year average reimbursement for: 9+ level posterior fusions (PF), 4-8 level PF, 4-8 level PF with anterior fusion (AF), 2-3 level PF with AF, 4-8 level AF, and 4-8 level posterior refusion. Reoperations and deaths were added to cost and subtracted from utility, respectively. Quality-adjusted life year per dollar spent was calculated using standardized methodology at 1-year time point and subsequent time points relying on maintenance of 1-year utility. RESULTS:Eighty-four patients (average age: 61.2 years, 60% female, body mass index [BMI]: 30.1) were analyzed after cervical deformity correction (average levels fused: 7.2, osteotomy used: 50%). Costs associated with index procedures were 9+ level PF ($76,617), 4-8 level PF ($40,596), 4-8 level PF with AF ($67,098), 4-8 level AF ($31,392), and 4-8 level posterior refusion ($35,371). Average 1-year reimbursement of surgery was $55,097 at 1 year with eight revisions and three deaths accounted for. Cost per quality-adjusted life year (QALY) gained to 1-year follow-up was $646,958 by EQ5D and $477,316 by NDI SF6D. If 1-year benefit is sustained, upper threshold of cost-effectiveness is reached 3-4.5 years after intervention. CONCLUSIONS:Medicare 1-year average reimbursement compared with 1-year QALYdescribed $646,958 by EQ5D and $477,316 by NDI SF6D. Cervical deformity surgeries reach accepted cost-effectiveness thresholds when benefit is sustained 3-4.5 years. Longer follow-up is needed for a more definitive cost-analysis, but these data are an important first step in justifying cost-utility ratio for cervical deformity correction.

Introduction/UNASSIGNED:Early Onset and Adolescent Idiopathic Scoliosis, relatively common diagnoses (∼3% general population), have been associated with developmental dysplasia of the hip (DDH); a more rare spectrum of anomalies related to the abnormal development of acetabulum, proximal femur, and hip joint. To the best of our knowledge, no high powered investigations have been performed in an attempt to assess incidence and associated risks of DDH in scoliosis patients. Methods/UNASSIGNED:The KID database was queried for ICD-9 codes from 2003 to 2012 pertaining to EOS (Congenital and Idiopathic <10y/o) and AIS patients. Descriptive analysis assessed patient demographics and yearly trends in hip dysplasia rates. EOS and AIS patients with hip dysplasia were isolated, and incidence of hospital admissions for associated anomalies (osteonecrosis, osteoarthritis, recurrent hip dislocation, hip ankylosis) and hip arthroplasty (total + partial) were investigated. Univariate analysis of hip pathology determined significant predictors of hip arthroplasty. Binary logistic regression analysis was used to determine the relationship between these predictors. Results/UNASSIGNED:111,827 scoliosis patients (EOS: 25,747; AIS: 77,183) were included. AIS patients were older (15.2 vs 4.3), more female (64.2% vs 52.1%), had a higher CCI (0.84 vs 0.64), and less racially diverse (all p < 0.001). The incidence of hip dysplasia was 1.4% for AIS patients and 3.9% for EOS patients (p < 0.001). Of the AIS (n = 1073) and EOS (n = 1005) patients with hip dysplasia, 0.3% (p > 0.05 between groups) developed hip osteonecrosis, 0% of patients were coded as having a hip labral tear, hip ankylosis, and 0.6% (EOS: 0.2%; AIS: 0.9%, p = 0.025) developed hip osteoarthritis. AIS patients were more likely to have recurrent hip dislocations (35.4% vs 17.0%, p < 0.001), and both groups had similar primary hip arthroplasty rates (6.7% vs 5.4%, p = 0.118) and revision hip arthroplasty rates (0% vs 0.4%, p = 0.053). Hip osteoarthritis (OR: 13.43[5.21-34.66], p=<0.001) and older age (OR: 1.039[1.007-1.073], p = 0.017) were the only significant predictors of hip arthroplasty (p=<.001). Conclusions/UNASSIGNED:The incidence of hip dysplasia in EOS and AIS populations is higher than that of the general population. The rate of DDH was 3.9% and 1.8% for EOS and AIS, respectively. While the incidence of DDH is higher, associated anomalies of osteoarthritis, osteonecrosis, labral tears, and ankylosis appear to be a minimal risk for AIS and EOS patients with Hip Dysplasia.

Optimizing functional outcomes and disability status are essential for effective surgical treatment of cervical spine disorders. Mental impairment is common among patients with cervical spine complaints; yet little is known about the impact of baseline mental status with respect to overall patient-reported outcomes. This was a retrospective analysis of patients with cervical spondylosis with myelopathy(CM) or radiculopathy(CR: cervical disc herniation, stenosis, or spondylosis without myelopathy) at 2-year follow-ups. Patients were assessed for several health-related quality of life HRQOL) measures at baseline and 24-months post-operatively: Neck Disability Index (NDI), Visual Analog Scale(VAS), Short Form-36(SF) Physical(PCS) and Mental(MCS) Components. Patients were dichotomized by MCS score: LOW-MCS(SF-MCS < 40th percentile) vs. HIGH-MCS(SF-MCS > 60th percentile). Independent and paired t-tests compared improvement in each group for HIGH-MCS and LOW-MCS cohorts. 375 patients were analyzed(65.4yrs, 67.6%F). LOW-MCS radiculopathy patients showed significant improvement in NDI, VAS Neck and Arm Pain(p < 0.05). HIGH-MCS radiculopathy patients showed greater improvement in NDI score, VAS Neck and Arm Pain, and improvement in PCS(all p < 0.05). Comparing baseline and 2-year follow-up, LOW-MCS CM patients showed significant improvement in PCS, NDI, VAS Neck and Arm Pain(p < 0.05). HIGH-MCS myelopathy patients group showed marked improvement in NDI scores, VAS Neck and Arm Pain(p < 0.05). LOW-MCS CR patients were more likely to be less satisfied 2-years post-op(p < 0.001). Postoperative CR patients with lower baseline mental status saw less improvement and significantly worse outcomes than patients with higher baseline mental status. Improving baseline mental health may improve post-operative recovery. Implementing additional screening and care can optimize functional outcomes and disability status for patients with CR.

BACKGROUND:Cardiac anomalies are prevalent in patients with bony spinal anomalies. Prior studies evaluating incidences of bony congenital anomalies of the spine are limited. The Kids' Inpatient Database (KID) yields national discharge estimates of rare pediatric conditions like congenital disorders. This study utilized cluster analysis to study patterns of concurrent vertebral anomalies, anal atresia, cardiac malformations, trachea-esophageal fistula, renal dysplasia, and limb anomalies (VACTERL anomalies) co-occurring in patients with spinal congenital anomalies. METHODS:Retrospective review of KID 2003-2012. KID-supplied hospital- and year-adjusted weights allowed for incidence assessment of bony spinal anomalies and cardiac, gastrointestinal, urinary anomalies of VACTERL. K-means clustering assessed relationships between most frequent anomalies within bony spinal anomaly discharges; k set to n - 1(n = first incidence of significant drop/little gain in sum of square errors within clusters). RESULTS:There were 12,039,432 KID patients 0-20 years. Incidence per 100,000 discharges: 2.5 congenital fusion of spine, 10.4 hemivertebra, 7.0 missing vertebra. The most common anomalies co-occurring with bony vertebral malformations were atrial septal defect (ASD 12.3%), large intestinal atresia (LIA 11.8%), and patent ductus arteriosus (PDA 10.4%). Top congenital cardiac anomalies in vertebral anomaly patients were ASD, PDA, and ventricular septal defect (VSD); all three anomalies co-occur at 6.6% rate in this vertebral anomaly population. Cluster analysis revealed that of bony anomaly discharges, 55.9% of those with PDA had ASD, 34.2% with VSD had PDA, 22.9% with LIA had ASD, 37.2% with ureter obstruction had LIA, and 35.5% with renal dysplasia had LIA. CONCLUSIONS:In vertebral anomaly patients, the most common co-occurring congenital anomalies were cardiac, renal, and gastrointestinal. Top congenital cardiac anomalies in vertebral anomaly patients were ASD, PDA, and VSD. VACTERL patients with vertebral anomalies commonly presented alongside cardiac and renal anomalies.

STUDY DESIGN/METHODS:Retrospective review. OBJECTIVE:Determine whether alignment or myelopathy improvement drives patient outcomes after cervical deformity (CD) corrective surgery. SUMMARY OF BACKGROUND DATA/BACKGROUND:CD correction involves radiographic malalignment correction and procedures to improve motor function and pain. It is unknown whether alignment or myelopathy improvement drives patient outcomes. METHODS:Inclusion: Patients with CD with baseline/1-year radiographic and outcome scores. Cervical alignment improvement was defined by improvement in Ames CD modifiers. modified Japanese Orthopaedic Association (mJOA) improvement was defined as mild [15-17], moderate [12-14], severe [<12]. Patient groups included those who only improved in alignment, those who only improved in mJOA, those who improved in both, and those who did not improve. Changes in quality-of-life scores (neck disability index [NDI], EuroQuol-5 dimensions [EQ-5D], mJOA) were evaluated between groups. RESULTS:A total of 70 patients (62 yr, 51% F) were included. Overall preoperative mJOA score was 13.04 ± 2.35. At baseline, 21 (30%) patients had mild myelopathy, 33 (47%) moderate, and 16 (23%) severe. Out of 70 patients 30 (44%) improved in mJOA and 13 (18.6%) met 1-year mJOA minimal clinically important difference. Distribution of improvement groups: 16/70 (23%) alignment-only improvement, 13 (19%) myelopathy-only improvement, 18 (26%) alignment and myelopathy improvement, and 23 (33%) no improvement. EQ-5D improved in 11 of 16 (69%) alignment-only patients, 11 of 18 (61%) myelopathy/alignment improvement, 13 of 13 (100%) myelopathy-only, and 10 of 23 (44%) no myelopathy/alignment improvement. There were no differences in decompression, baseline alignment, mJOA, EQ-5D, or NDI between groups. Patients who improved only in myelopathy showed significant differences in baseline-1Y EQ-5D (baseline: 0.74, 1 yr:0.83, P < 0.001). One-year C2-S1 sagittal vertical axis (SVA; mJOA r = -0.424, P = 0.002; EQ-5D r = -0.261, P = 0.050; NDI r = 0.321, P = 0.015) and C7-S1 SVA (mJOA r = -0.494, P < 0.001; EQ-5D r = -0.284, P = 0.031; NDI r = 0.334, P = 0.010) were correlated with improvement in health-related qualities of life. CONCLUSION/CONCLUSIONS:After CD-corrective surgery, improvements in myelopathy symptoms and functional score were associated with superior 1-year patient-reported outcomes. Although there were no relationships between cervical-specific sagittal parameters and patient outcomes, global parameters of C2-S1 SVA and C7-S1 SVA showed significant correlations with overall 1-year mJOA, EQ-5D, and NDI. These results highlight myelopathy improvement as a key driver of patient-reported outcomes, and confirm the importance of sagittal alignment in patients with CD. LEVEL OF EVIDENCE/METHODS:3.