Progression to fusion after lumbar laminectomy for degenerative lumbar spondylolisthesis: Rate and risk-factors. A national database study.

OBJECTIVE: Lumbar laminectomy is often utilized in the treatment of degenerative lumbar spondylolisthesis. Risk factors that contribute to reoperation rates, in particular to progression to fusion, are poorly understood. We aimed to identify rate and risk factors of lumbar fusion surgery following lumbar laminectomy for the treatment of degenerative lumbar spinal spondylolisthesis. METHODS: Our sample was obtained from the national MarketScan Commercial Claims and Encounters Database. We reviewed patients undergoing lumbar laminectomy for stable degenerative lumbar spondylolisthesis (Grade-1) at one or two levels between January 2007 and December 2016. RESULTS: A total of 33,681 patients were included. By 2 years after the index operation, 2.48 % of patients had required lumbar fusion surgery. Female sex was associated with lower odds (OR 0.8, 95 %CI 0.7-0.9) of reoperation for fusion. Diabetes (OR 1.2, 95 %CI 1.1-1.4), rheumatoid arthritis (OR 1.5, 95 %CI 1.2-1.7) and clinical presentation with LBP (OR 2.1, 95 %CI 1.6-2.9), lower extremity weakness (OR 1.4, 95 %CI 1.1-1.5), as well as occurrence of a postoperative neurological complications (OR 2.0, 95 %CI 1.1-3.4) increased the odds ratio for requiring fusion surgery within two years after lumbar laminectomy. CONCLUSION: In this large cross-sectional sample of a national claims database consisting of lumbar laminectomy patients for the treatment of spondylolisthesis, approximately 2.5 % required subsequent lumbar fusion. Several modifiable risk factors for fusion progression were identified, which may guide clinicians in shared decision-making and to help identify patients with elevated post-operative risk providing potential leverage point for prevention.

The Impact of Preoperative Myelopathy on Postoperative Outcomes among Anterior Cervical Discectomy and Fusion Procedures in the Nonelderly Adult Population: A Propensity-Score Matched Study.

STUDY DESIGN: Retrospective cohort study. PURPOSE: Anterior cervical discectomy and fusion (ACDF) is a common surgical intervention for patients diagnosed with cervical degenerative diseases with or without myelopathy. A thorough understanding of outcomes in patients with and without myelopathy undergoing ACDF is required because of the widespread utilization of ACDF for these indications. OVERVIEW OF LITERATURE: Non-ACDF approaches achieved inferior outcomes in certain myelopathic cases. Studies have compared patient outcomes across procedures, but few have compared outcomes concerning myelopathic versus nonmyelopathic cohorts. METHODS: The MarketScan database was queried from 2007 to 2016 to identify adult patients who were ≤65 years old, and underwent ACDF using the international classification of diseases 9th version and current procedural terminology codes. Nearest neighbor propensity-score matching was employed to balance patient demographics and operative characteristics between myelopathic and nonmyelopathic cohorts. RESULTS: Of 107,480 patients who met the inclusion criteria, 29,152 (27.1%) were diagnosed with myelopathy. At baseline, the median age of patients with myelopathy was higher (52 years vs. 50 years, p <0.001), and they had a higher comorbidity burden (mean Charlson comorbidity index, 1.92 vs. 1.58; p <0.001) than patients without myelopathy. Patients with myelopathy were more likely to undergo surgical revision at 2 years (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.54-1.73) or are readmitted within 90 days (OR, 1.27; 95% CI, 1.20-1.34). After patient cohorts were matched, patients with myelopathy remained at elevated risk for reoperation at 2 years (OR, 1.55; 95% CI, 1.44-1.67) and postoperative dysphagia (2.78% vs. 1.68%, p <0.001) compared to patients without myelopathy. CONCLUSIONS: We found inferior postoperative outcomes at baseline for patients with myelopathy undergoing ACDF compared to patients without myelopathy. Patients with myelopathy remained at significantly greater risk for reoperation and readmission after balancing potential confounding variables across cohorts, and these differences in outcomes were largely driven by patients with myelopathy undergoing 1-2 level fusions.

Clinical Outcomes and Cost Profiles for Cage and Allograft Anterior Cervical Discectomy and Fusion Procedures in the Adult Population: A Propensity Score-Matched Study.

STUDY DESIGN: Retrospective cohort study. PURPOSE: To characterize the postoperative outcomes and economic costs of anterior cervical discectomy and fusion (ACDF) procedures using synthetic biomechanical intervertebral cage (BC) and structural allograft (SA) implants. OVERVIEW OF LITERATURE: ACDF is a common spine procedure that typically uses an SA or BC for the cervical fusion. Previous studies that compared the outcomes between the two implants were limited by small sample sizes, short-term postoperative outcomes, and procedures with single-level fusion. METHODS: Adult patients who underwent an ACDF procedure in 2007-2016 were included. Patient records were extracted from MarketScan, a national registry that captures person-specific clinical utilization, expenditures, and enrollments across millions of inpatient, outpatient, and prescription drug services. Propensity-score matching (PSM) was employed to match the patient cohorts across demographic characteristics, comorbidities, and treatments. RESULTS: Of 110,911 patients, 65,151 (58.7%) received BC implants while 45,760 (41.3%) received SA implants. Patients who underwent BC surgeries had slightly higher reoperation rates within 1 year after the index ACDF procedure (3.3% vs. 3.0%, p=0.004), higher postoperative complication rates (4.9% vs. 4.6%, p=0.022), and higher 90-day readmission rates (4.9% vs. 4.4%, p =0.001). After PSM, the postoperative complication rates did not vary between the two cohorts (4.8% vs. 4.6%, p=0.369), although dysphagia (2.2% vs. 1.8%, p<0.001) and infection (0.3% vs. 0.2%, p=0.007) rates remained higher for the BC group. Other outcome differences, including readmission and reoperation, decreased. Physician's fees remained high for BC implantation procedures. CONCLUSIONS: We found marginal differences in clinical outcomes between BC and SA ACDF interventions in the largest published database cohort of adult ACDF surgeries. After adjusting for group-level differences in comorbidity burden and demographic characteristics, BC and SA ACDF surgeries showed similar clinical outcomes. Physician's fees, however, were higher for BC implantation procedures.

Clinical Outcomes and Cost Differences Between Patients Undergoing Primary Anterior Cervical Discectomy and Fusion Procedures with Private or Medicare Insurance: A Propensity Score-Matched Study.

OBJECTIVE: We assessed whether the insurance type reflects a patient's quality of care after an anterior discectomy and fusion (ACDF) procedure by comparing differences in the postoperative complications, readmission rates, reoperation rates, lengths of hospital stay, and cost of treatment between patients with Medicare versus private insurance. METHODS: Propensity score matching was used to match patient cohorts insured by Medicare and private insurance in the MarketScan Commercial Claims and Encounters Database (2007-2016). Age, sex, year of operation, geographic region, comorbidities, and operative factors were used to match cohorts of patients who had undergone an ACDF procedure. RESULTS: A total of 110,911 patients met the inclusion criteria. Of these patients, 97,543 patients (87.9%) were privately insured and 13,368 patients (12.1%) were insured by Medicare. The propensity score matching algorithm matched 7026 privately insured patients to 7026 Medicare patients. After matching, no significant differences were found in the 90-day postoperative complication rates, lengths of stay, or reoperation rates between the Medicare and privately insured cohorts. The Medicare group had had lower postoperative readmission rates for all time points: 30 days (1.8% vs. 4.6%; P < 0.001), 60 days (2.5% vs. 6.3%; P < 0.001), and 90 days (4.2% vs. 7.7%; P < 0.001). The median payment to physicians was significantly lower for the Medicare group ($3885 vs. $5601; P < 0.001). CONCLUSIONS: In the present study, propensity score matched patients covered by Medicare and private insurance who had undergone an ACDF procedure had had similar treatment outcomes.

Operative Versus Nonoperative Treatment of Acute Achilles Tendon Rupture: A Propensity Score-Matched Analysis of a Large National Dataset.

Background: No consensus exists regarding the superiority of operative versus nonoperative management for Achilles tendon ruptures, as multiple randomized controlled trials conducted since the advent of early mobilization protocols have found outcomes for these 2 interventions to be more similar than were previously held. Purpose: To use a large national database to (1) compare reoperation and complication rates between operative and nonoperative treatment of acute Achilles tendon ruptures and (2) evaluate trends in treatment and cost over time. Study Design: Cohort study; Level of evidence, 3. Methods: The MarketScan Commercial Claims and Encounters database was used to identify an unmatched cohort of 31,515 patients who sustained primary Achilles tendon ruptures between 2007 and 2015. Patients were stratified into operative and nonoperative treatment groups, and a propensity score-a matching algorithm-was used to establish a matched cohort of 17,996 patients (n = 8993 per treatment group). Reoperation rates, complications, and aggregate treatment costs were compared between groups with an alpha level of .05. A number needed to harm (NNH) was calculated from the absolute risk difference in complications between cohorts. Results: The operative cohort experienced a significantly larger total number of complications within 30 days of injury (1026 vs 917; P = .0088). The absolute increase in cumulative risk was 1.2% with operative treatment, which resulted in an NNH of 83. Neither 1-year (1.1% [operative] vs 1.3% [nonoperative]; P = .1201) nor 2-year reoperation rates (1.9% [operative] vs 2% [nonoperative]; P = .2810) were significantly different. Operative care was more expensive than nonoperative care at 9 months and 2 years after injury; however, there was no difference in cost between treatments at 5 years. Before matching, the rate of surgical repair for Achilles tendon rupture remained stable, from 69.7% to 71.7% between 2007 and 2015, indicating little change in practice in the United States. Conclusion: Results indicated no differences in reoperation rates between operative and nonoperative management of Achilles tendon ruptures. Operative management was associated with an increased risk of complications and higher initial costs, which dissipated over time. Between 2007 and 2015 the proportion of Achilles tendon ruptures managed operatively remained similar despite increasing evidence that nonoperative management of Achilles tendon rupture may provide equivalent outcomes.

Do Epidural Steroid Injections Affect Outcomes and Costs in Cervical Degenerative Disease? A Retrospective MarketScan Database Analysis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To investigate the effect of preoperative epidural steroid injection (ESI) on quality outcomes and costs in patients undergoing surgery for cervical degenerative disease. METHODS: We queried the MarketScan database, a national administrative claims dataset, to identify patients who underwent cervical degenerative surgery from 2007 to 2016. Patients under 18 and patients with history of tumor or trauma were excluded. Patients were stratified by ESI use at 3, 6, 12, 18, and 24 or more months preoperative. Propensity score matched controls for these groups were obtained. Baseline demographics, postoperative complications, reoperations, readmissions, and costs were compared via univariate and multivariate analysis. RESULTS: 97 117 patients underwent cervical degenerative surgery, of which 29 963 (30.7%) had ESI use at any time preoperatively. Overall, 90-day complication rate was not significantly different between groups. The ESI cohorts had shorter length of stay, but higher 90-day readmission and reoperation rates. ESI use was associated with higher total payments through the 2-year follow-up period. Among patients who received preoperative ESI, male sex, history of cancer, obesity, PVD, rheumatoid arthritis, nonsmokers, cervical myelopathy, BMP use, anterior approach, 90-day complication, 90-day reoperation, and 90-day readmission were independently associated with increased 90-day total cost. CONCLUSION: ESI can offer pain relief in some patients refractory to other conservative management techniques, but those who eventually undergo surgery have greater healthcare resource utilization. Certain characteristics can predispose patients who receive preoperative ESI to incur higher healthcare costs.

Achilles Tendon Repairs: Identification of Risk Factors for and Economic Impact of Complications and Reoperation.

BACKGROUND: Compared with nonoperative management, Achilles tendon repair is associated with increased rates of complications and increased initial healthcare cost. However, data are currently lacking on the risk factors for these complications and the added healthcare cost associated with common preoperative comorbidities. HYPOTHESIS: Identify the independent risk factors for complications and reoperation after acute Achilles tendon repair and calculate the added cost of care associated with having each preoperative risk factor. STUDY DESIGN: Retrospective cohort study. LEVEL OF EVIDENCE: Level 3. METHODS: A retrospective review of a large commercial claims database was performed to identify patients who underwent primary operative management for Achilles tendon rupture between 2007 and 2016. The primary outcome measures of the study were risk factors for (1) postoperative complications, (2) revision surgery, and (3) increased healthcare resource utilization. RESULTS: A total of 50,279 patients were included. The overall complication rate was 2.7%. The most common 30-day complication was venous thromboembolism (1.2%). The rate of revision surgery was 2.5% at 30 days and 4.3% at 2 years. Independent risk factors for 30-day complications in our cohort included increasing age, hyperlipidemia, hypertension, female sex, obesity, and diabetes. Independent risk factors for revision surgery within 2 years included female sex, tobacco use, hypertension, obesity, and the presence of any postoperative complication. The average 5-year cost of operative intervention was $17,307. The need for revision surgery had the largest effect on 5-year overall cost, increasing it by $6776.40. This was followed by the presence of a postoperative complication ($3780), female sex ($3207.70), and diabetes ($3105). CONCLUSION: Achilles tendon repair is a relatively low-risk operation. Factors associated with postoperative complications include increasing age, hyperlipidemia, hypertension, female sex, obesity, and diabetes. Factors associated with the need for revision surgery include female sex, hypertension, obesity, and the presence of any postoperative complication. Female sex, diabetes, the presence of any complication, and the need for revision surgery had the largest added costs associated with them. CLINICAL RELEVANCE: Surgeons can use this information for preoperative decision-making and during the informed consent process.

Comparison of Deep Learning and Classical Machine Learning Algorithms to Predict Postoperative Outcomes for Anterior Cervical Discectomy and Fusion Procedures With State-of-the-art Performance.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: Due to anterior cervical discectomy and fusion (ACDF) popularity, it is important to predict postoperative complications, unfavorable 90-day readmissions, and two-year reoperations to improve surgical decision-making, prognostication, and planning. SUMMARY OF BACKGROUND DATA: Machine learning has been applied to predict postoperative complications for ACDF; however, studies were limited by sample size and model type. These studies achieved ≤0.70 area under the curve (AUC). Further approaches, not limited to ACDF, focused on specific complication types and resulted in AUC between 0.70 and 0.76. MATERIALS AND METHODS: The IBM MarketScan Commercial Claims and Encounters Database and Medicare Supplement were queried from 2007 to 2016 to identify adult patients who underwent an ACDF procedure (N=176,816). Traditional machine learning algorithms, logistic regression, and support vector machines, were compared with deep neural networks to predict: 90-day postoperative complications, 90-day readmission, and two-year reoperation. We further generated random deep learning model architectures and trained them on the 90-day complication task to approximate an upper bound. Last, using deep learning, we investigated the importance of each input variable for the prediction of 90-day postoperative complications in ACDF. RESULTS: For the prediction of 90-day complication, 90-day readmission, and two-year reoperation, the deep neural network-based models achieved AUC of 0.832, 0.713, and 0.671. Logistic regression achieved AUCs of 0.820, 0.712, and 0.671. Support vector machine approaches were significantly lower. The upper bound of deep learning performance was approximated as 0.832. Myelopathy, age, human immunodeficiency virus, previous myocardial infarctions, obesity, and documentary weakness were found to be the strongest variable to predict 90-day postoperative complications. CONCLUSIONS: The deep neural network may be used to predict complications for clinical applications after multicenter validation. The results suggest limited added knowledge exists in interactions between the input variables used for this task. Future work should identify novel variables to increase predictive power.

Chronic Opioid Use Prior to ACDF Surgery Is Associated with Inferior Postoperative Outcomes: A Propensity-Matched Study of 17,443 Chronic Opioid Users.

OBJECTIVE: Candidates for anterior cervical discectomy and fusion (ACDF) have a higher rate of opioid use than does the public, but studies on preoperative opioid use have not been conducted. We aimed to understand how preoperative opioid use affects post-ACDF outcomes. METHODS: The MarketScan Database was queried from 2007 to 2015 to identify adult patients who underwent an ACDF. Patients were classified into separate cohorts based on the number of separate opioid prescriptions in the year before their ACDF. Ninety-day postoperative complications, postoperative readmission, reoperation, and total inpatient costs were compared between opioid strata. Propensity score-matched patient cohorts were calculated to balance comorbidities across groups. RESULTS: Of 81,671 ACDF patients, 31,312 (38.3%) were nonusers, 30,302 (37.1%) were mild users, and 20,057 (24.6%) were chronic users. Chronic opioid users had a higher comorbidity burden, on average, than patients with less frequent opioid use (P < 0.001). Chronic opioid users had higher rates of postoperative complications (9.1%) than mild opioid users (6.0%) and nonusers (5.3%) (P < 0.001) and higher rates of readmission and reoperation. After balancing opioid nonusers versus chronic opioid users along with demographic characteristics, preoperative comorbidity, and operative characteristics, postoperative complications remained elevated for chronic opioid users relative to opioid nonusers (8.6% vs. 5.7%; P < 0.001), as did rates of readmission and reoperation. CONCLUSIONS: Chronic opioid users had more comorbidities than opioid nonusers and mild opioid users, longer hospitalizations, and higher rates of postoperative complication, readmission, and reoperation. After balancing patients across covariates, the outcome differences persisted, suggesting a durable association between preoperative opioid use and negative postoperative outcomes.

Patient-Specific Risk Factors Exist for Hip Fractures After Arthroscopic Femoroacetabular Impingement Surgery, But Not for Dislocation-An Analysis of More Than 25,000 Hip Arthroscopies.

Purpose: To identify postoperative complications and risk factors associated with hip fracture and dislocation following primary arthroscopic surgical management of femoroacetabular impingement (FAI) syndrome. Methods: MarketScan was queried to identify patients who underwent FAI surgery from 2007 to 2016. Patients were stratified into 2 groups: acetabuloplasty only or femoroplasty only. A subanalysis of combined acetabuloplasty and femoroplasty also was undertaken. Surgical outcomes were followed postoperatively for 180 days. Multivariate logistic regression was used to control for with an alpha value of 0.05 set as significant. Results: This study identified 13,809 patients (mean age, 36.3 years) who underwent primary acetabuloplasty or femoroplasty. We also identified 10,026 patients who underwent both procedures. Postoperative complication rates were similar between the cohorts (acetabuloplasty 17.1%, femoroplasty 19.9%, P = .0622). Rates of hip fracture (femoroplasty: 2.4% vs acetabuloplasty: 2.0%, P = .0302) and heterotopic ossification (femoroplasty: 11.3% vs acetabuloplasty: 8.8%, P < .0001) were greater in the femoroplasty-only cohort. Combined acetabuloplasty and femoroplasty was associated with the greatest complication burden of 21.6% (P < .0001). After multivariate regression, differences in age, sex, comorbid status, or procedure type did not influence odds in risk for postoperative hip dislocation. Adjusted data showed that neither femoroplasty nor acetabuloplasty influenced odds of hip fracture (P > .05). Patients who were aged younger than 20 years old were significantly less likely to fracture their hips postoperatively than patients aged 60+ years (odds ratio 0.3, 95% confidence interval 0.1-0.8). Hypertension was independently associated with increased odds of hip fracture (odds ratio 1.7, 95% confidence interval 1.2-3.5). Conclusions: Older age, male sex, and hypertension all carry increased risk for a hip fracture following acetabuloplasty or femoroplasty. Patient- and procedure-specific factors that could be assessed with this database did not influence risk for hip dislocation. Level of Evidence: Level III; retrospective comparative observation trial.

Factors Which Predict Adverse Outcomes in Anterior Cervical Discectomy and Fusion Procedures in the Nonelderly Adult Population.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: The largest published cohort of anterior cervical discectomy and fusion (ACDF) patients was queried to better characterize demographic and operative factors that predict 90-day complication and 2-year reoperation risk. SUMMARY OF BACKGROUND DATA: The MarketScan Database was queried from 2007 to 2016 to identify adult patients until 65 years, who underwent an ACDF procedure using International Classification of Diseases 9th Version (ICD-9) and Current Procedural Terminology (CPT) codes. MarketScan is a national insurance claims database that contains millions of patient records across all 50 states. METHODS: Multivariate logistic regression was used to identify factors associated with complications until 90 days and reoperations until 2 years. RESULTS: Of 138,839 ACDF procedures, 8500 patients (6.1%) experienced a complication within 90 days of the ACDF, and 7433 (5.4%) underwent surgical revision by 2 years. While the use of anterior cervical plating did not predict 2-year reoperation, it was associated with dramatically reduced 90-day complication risk (adjusted odds ratio [aOR]: 0.32; 95% confidence interval [CI]: 0.30-0.34; P <0.001). Upon multivariate analysis, female sex (aOR: 0.83; 95% CI: 0.79-0.87; P <0.001) was associated with decreased risk of 2-year reoperation, while depression predicted a 50% increase in reoperation risk (aOR: 1.51; 95% CI: 1.43-1.59; P <0.001). The single largest factor associated with reoperation risk, however, was the presence of a 90-day postoperative complication (aOR: 1.79; 95% CI: 1.66-1.94; P <0.001). CONCLUSION: Increased patient comorbidities and the use of bone morphogenic protein were found to increase the risk for postoperative complications, while cervical plating was associated with a strong decline in this risk. In addition, poor patient mental health outweighed the adverse of impact of other comorbidities on 2-year revision risk. The presence of a postoperative complication was the key modifiable risk factor associated with reoperation risk. Conclusions from this study may help surgeons better identify high-risk ACDF patients for more careful patient selection, counseling, informed consent, and management.

Imageless Computer Navigation Reduces 5-Year All-Cause Revision Rates After Primary Total Knee Arthroplasty.

BACKGROUND: The use of surgical navigation has been shown to reduce revision rates after total knee arthroplasty (TKA) in patients <65 years of age. It is unknown if this benefit extends to older patients. We hypothesized that the use of surgical navigation would reduce rates of all-cause revision in patients of all ages. METHODS: In this cohort study, we queried the Truven MarketScan all-payer database to identify patients who underwent TKA from 2007 to 2015. Current Procedural Terminology codes were used to create 2 groups based on whether intraoperative navigation was used. Demographics, comorbidities, complications, and revision rates were determined. International Classification of Diseases codes were used to determine reasons for revision. RESULTS: The conventional TKA cohort included 312,173 patients. The navigation cohort included 20,881 patients. There were not any clinically significant differences in demographics between the cohorts. All-cause revision rates were lower in the navigation cohort at 1 year (0.4% vs 0.5%, P = .04), 2 years (0.7% vs 0.9%, P = .003), and 5 years (0.9% vs 1.3%, P < .001) of follow-up. Revisions for mechanical loosening were more common in the conventional cohort (30.8% vs 21.9%, P = .009). Rates of revision for other causes, including infection, did not differ between groups, with the numbers available. CONCLUSION: The use of surgical navigation yielded a 30.7% reduction in the all-cause revision rate at 5-year follow-up compared to conventional TKA. This benefit increased as follow-up duration increased. Increased usage of this inexpensive technology, from the current 6.3% in this US cohort, may reduce healthcare costs. LEVEL OF EVIDENCE: III.

Risk Factors for Revision Surgery After Primary Adult Thoracolumbar Deformity Surgery.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: The aim was to identify the risk factors for revision surgery within 2 years of patients undergoing primary adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: Previous literature reports estimate 20% of patients undergoing thoracolumbar ASD correction undergo reoperation within 2 years. There is limited published data regarding specific risk factors for reoperation in ASD surgery in the short term and long term. METHODS: The authors queried the MarketScan database in order to identify patients who were diagnosed with a spinal deformity and underwent ASD surgery from 2007 to 2015. Patient-level factors and revision risk were investigated during 2 years after primary ASD surgery. Patients under the age of 18 years and those with any prior history of trauma or tumor were excluded from this study. RESULTS: A total 7422 patients underwent ASD surgery during 2007-2015 in the data set. Revision rates were 13.1% at 90 days, 14.5% at 6 months, 16.7% at 1 year, and 19.3% at 2 years. In multivariate multiple logistic regression analysis, obesity [adjusted odds ratio (OR): 1.58, P<0.001] and tobacco use (adjusted OR: 1.38, P=0.0011) were associated with increased odds of reoperation within 2 years. Patients with a combined anterior-posterior approach had lower odds of reoperation compared with those with posterior only approach (adjusted OR: 0.66, P=0.0117). CONCLUSIONS: Obesity and tobacco are associated with increased odds of revision surgery within 2 years of index ASD surgery. Male sex and combined surgical approach are associated with decreased odds of revision surgery.

The impact of osteoporosis on adult deformity surgery outcomes in Medicare patients.

OBJECTIVE: To identify the impact of osteoporosis (OS) on postoperative outcomes in Medicare patients undergoing ASD surgery. BACKGROUND: Patients with OP and advanced age experience higher than average rates of ASD. However, poor bone density could undermine the durability of a deformity correction. METHODS: We queried the MarketScan Medicare Supplemental database to identify patients Medicare patients who underwent ASD surgery from 2007 to 2016. RESULTS: A total of 2564 patients met the inclusion criteria of this study, of whom n = 971 (61.0%) were diagnosed with osteoporosis. Patients with OP had a similar 90-day postoperative complication rates (OP: 54.6% vs. non-OP: 49.2%, p = 0.0076, not significant after multivariate regression correction). This was primarily driven by posthemorrhagic anemia (37.6% in OP, vs. 33.1% in non-OP). Rates of revision surgery were similar at 90 days (non-OP 15.0%, OP 16.8%), but by 2 years, OP patients had a significantly higher reoperation rate (30.4% vs. 22.9%, p < 0.0001). In multivariate regression analysis, OP increased odds for revision surgery at 1 year (OR 1.4) and 2 years (OR 1.5) following surgery (all p < 0.05). OP was also an independent predictor of readmission at all time points (90 days, OR 1.3, p < 0.005). CONCLUSION: Medicare patients with OP had elevated rates of complications, reoperations, and outpatient costs after undergoing primary ASD surgery.

Surgical Outcomes of Human Immunodeficiency Virus-positive Patients Undergoing Lumbar Degenerative Surgery.

STUDY DESIGN: This was a retrospective cohort studying using a national administrative database. OBJECTIVE: The objective of this study was to determine the postoperative complications and quality outcomes of the human immunodeficiency virus (HIV)-positive patients undergoing surgical management for lumbar degenerative disease (LDD). METHODS: This study identified patients with who underwent surgery for LDD between 2007 and 2016. Patients were stratified based on whether they were HIV positive at the time of surgery. Multivariate regression was utilized to reduce the confounding of baseline covariates. Patients who underwent 3 or more levels of surgical correction were under the age of 18 years, or those with any prior history of trauma or tumor were excluded from this study. Baseline comorbidities, postoperative complication rates, and reoperation rates were determined. RESULTS: A total of 120,167 patients underwent primary lumbar degenerative surgery, of which 309 (0.26%) were HIV positive. In multivariate regression analysis, the HIV-positive cohort was more likely to be readmitted at 30 days [odds ratio (OR)=1.9, 95% confidence interval (CI): 1.2-2.8], 60 days (OR=1.7, 95% CI: 1.2-2.5), and 90 days (OR=1.5, 95% CI: 1.0-2.2). The HIV-positive cohort was also more likely to experience any postoperative complication (OR=1.7, 95% CI: 1.2-2.3). Of the major drivers identified, HIV-positive patients had significantly greater odds of cerebrovascular disease and postoperative neurological complications (OR=3.8, 95% CI: 1.8-6.9) and acute kidney injury (OR=3.4, 95% CI: 1.3-7.1). Costs of index hospitalization were not significantly different between the 2 cohorts ($30,056 vs. $29,720, P=0.6853). The total costs were also similar throughout the 2-year follow-up period. CONCLUSION: Patients who are HIV positive at the time of LDD surgery are at a higher risk for postoperative central nervous system and renal complications and unplanned readmissions.

Outcome Measures of Medicare Patients With Diabetes Mellitus Undergoing Thoracolumbar Deformity Surgery.

STUDY DESIGN: This was a retrospective study. OBJECTIVE: The objective of this study was to identify the impact of diabetes on postoperative outcomes in Medicare patients undergoing adult spinal deformity (ASD) surgery. METHODS: We queried the MarketScan Medicare database to identify patients who underwent ASD surgery from 2007 to 2016. Patients were then stratified based on diabetes status at the time of the index operation. Patients not enrolled in the Medicare dataset and those with any prior history of trauma or tumor were excluded from this study. RESULTS: A total of 2564 patients met the inclusion criteria of this study, of which n=746 (29.1.%) were diabetic. Patients with diabetes had a higher rate of postoperative infection than nondiabetic patients (3.1% vs. 1.7%, P<0.05) within 90 days. Renal complications were also more elevated in the diabetic cohort (3.2% vs. 1.3%, P<0.05). Readmission rates were significantly higher in the diabetes cohort through of 60 days (15.2% vs. 11.8%, P<0.05) and 90 days (17.0% vs. 13.4%, P<0.05). When looking specifically at the outpatient payments, patients with diabetes did have a higher financial burden at 60 days ($8147 vs. $6956, P<0.05) and 90 days ($10,126 vs. $8376, P<0.05). CONCLUSIONS: In this study, diabetic patients who underwent ASD surgery had elevated rates of postoperative infection, outpatient costs, and rates of readmissions within 90 days. Further research should investigate the role of poor glycemic control on spine surgery outcomes.

Age-Adjusted Normative Values for Hip Patient-Reported Outcome Measures.

BACKGROUND: Patient-reported outcome measures (PROMs) are essential clinical instruments used for assessing patient function, assisting in clinical decision making, and quantifying outcomes of surgical and nonsurgical management. However, PROMs are often designed using patients with preexisting pathology and typically assume that a patient without the pathology would have a perfect or near perfect score. This may result in unrealistic expectations or falsely underestimate how well a patient is doing after treatment. The influence of age on PROMs about the hip of healthy individuals has not been studied. HYPOTHESIS: We hypothesize that in asymptomatic individuals hip-specific PROM scores will decrease in an age-dependent manor. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: In this multicenter survey study, volunteers who denied preexisting hip pathology and previous hip surgery completed 3 PROMs online or as traditional paper questionnaires. The International Hip Outcome Tool (iHOT), the modified Harris Hip Score (mHHS), and the Hip Outcome Score-Activities of Daily Living (HOS-ADL) and HOS-Sport were completed. Analysis of variance with a Tukey post hoc test was used to analyze differences in PROMs among subgroups. An independent-samples Student t test and a χ2 test were used to analyze differences in continuous and categorical data, respectively. RESULTS: In total 496, 571, 534, and 532 responses were collected for the iHOT, mHHS, HOS-ADL, and HOS-Sport, respectively. Respondents' PROMs were scored and arranged into 3 groups by age: <40 years, 40 to 60 years, and >60 years. The iHOT, mHHS, HOS-ADL, and HOS-Sport of these asymptomatic respondents all decreased in an age-dependent manner: iHOT (<40, 94.1; 40-60, 92.4; >60, 87.0), mHHS (<40, 94.8; 40-60, 91.3; >60, 89.1), HOS-ADL (<40, 98.4; 40-60, 95.0; >60, 90.9), and HOS-Sport (<40, 95.7; 40-60, 82.9; >60, 72.9) (analysis of variance between-group differences, P < .05). CONCLUSION: This study demonstrated that the iHOT, mHHS, and HOS-ADL and HOS-Sport scores in asymptomatic people decrease in an age-dependent manner. It is important to compare a patient's outcome scores with the age-normalized scores to establish an accurate reference frame with which to interpret outcomes.

Obesity in Patients Undergoing Lumbar Degenerative Surgery-A Retrospective Cohort Study of Postoperative Outcomes.

STUDY DESIGN: Retrospective cohort studying using a national, administrative database. OBJECTIVE: The aim of this study was to determine the postoperative complications and quality outcomes of patients with and without obesity undergoing surgical management for lumbar degenerative disease (LDD). SUMMARY OF BACKGROUND DATA: Obesity is a global epidemic that negatively impacts health outcomes. Characterizing the effect of obesity on LDD surgery is important given the growing elderly obese population. METHODS: This study identified patients with who underwent surgery for LDD between 2007 and 2016. Patients were stratified based on whether the patient had a concurrent diagnosis of obesity at time of surgery. Propensity score matching (PSM) was then utilized to mitigate intergroup differences between patients with and without obesity. Patients who underwent three or more levels surgical correction, were under the age of 18 years, or those with any previous history of trauma or tumor were excluded from this study. Baseline comorbidities, postoperative complication rates, and reoperation rates were determined. RESULTS: A total of 67,215 patients underwent primary lumbar degenerative surgery, of which 22,405 (33%) were obese. After propensity score matching, baseline covariates of the two cohorts were similar. The complication rate was 8.3% in the nonobese cohort and 10.4% in the obese cohort (P < 0.0001). Patients with obesity also had longer lengths of stay (2.7 days vs. 2.4 days, P < 0.05), and higher rates of reoperation and readmission at all time-points through the study follow-up period to their nonobese counterparts (P < 0.05). Including payments after discharge, lumbar degenerative surgery in patients with obesity was associated with higher payments throughout the 2-year follow-up period ($68,061 vs. $59,068 P < 0.05). CONCLUSION: Patients with a diagnosis of obesity at time of LDD surgery are at a higher risk for postoperative complications, reoperation, and readmission.Level of Evidence: 4.

Single-Stage Versus Multistage Surgical Management of Single- and Two-Level Lumbar Degenerative Disease.

OBJECTIVE: To determine postoperative complications and quality outcomes of single-stage and multistage surgical management for lumbar degenerative disease (LDD). METHODS: This retrospective cohort study using a national administrative database identified patients who underwent surgery for LDD between 2007 and 2016. Patients were stratified based on whether their surgeon chose to perform single-stage or multistage LDD surgery, and these cohorts were mutually exclusive. Propensity score matching was used to mitigate intergroup differences between single-stage and multistage patients. Patients who underwent ≥3 levels of surgical correction, who were <18 years old, or who had any prior history of trauma or tumor were excluded from the study. Baseline comorbidities, postoperative complication rates, and reoperation rates were determined. RESULTS: Primary surgery for LDD was performed in 47,190 patients; 9438 (20%) of these patients underwent multistage surgery. After propensity score matching, baseline covariates of the 2 cohorts were similar. The complication rate was 6.1% in the single-stage cohort and 11.0% in the multistage cohort. Rates of posthemorrhagic anemia, infection, wound complication, deep vein thrombosis, and hematoma all were higher in the multistage cohort. Length of stay, revisions, and readmissions were also significantly higher in the multistage cohort. Through 2 years of follow-up, multistage surgery was associated with higher payments throughout the 2-year follow-up period ($57,036 vs. $39,318, P < 0.05). CONCLUSIONS: Single-stage surgery for LDD demonstrated improved outcomes and lower health care utilization. Spine surgeons should carefully consider single-stage surgery when treating patients with LDD requiring <3 levels of correction.

Anterior Cervical Discectomy and Fusion Versus Laminoplasty for Multilevel Cervical Spondylotic Myelopathy: A National Administrative Database Analysis.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) is effective for the treatment of single-level cervical spondylotic myelopathy (CSM). However, the data surrounding multilevel CSM have remained controversial. One alternative is laminoplasty, although evidence comparing these strategies has remained sparse. In the present report, we retrospectively reviewed the readmission and reoperation rates for patients who had undergone ACDF or laminoplasty for multilevel CSM from a national longitudinal administrative claims database. METHODS: We queried the MarketScan Commercial Claims and Encounters database to identify patients who had undergone ACDF or laminoplasty for multilevel CSM from 2007 to 2016. The patients were stratified by operation type. Patients aged <18 years, patients with a history of tumor or trauma, and patients who had undergone anteroposterior approach were excluded from the present study. RESULTS: A total of 5445 patients were included, of whom 1521 had undergone laminoplasty. A matched cohort who had undergone ACDF was identified. The overall 90-day postoperative complication rate was greater in the laminoplasty cohort (odds ratio, 1.48; 95% confidence interval, 1.18-1.86; P < 0.0001). The mean length of stay and 90-day readmission rates were greater in the laminoplasty cohort. The hospital and total payments of the index hospitalization were greater in the ACDF cohort, as were the total payments for ≤2 years after the index hospitalization. CONCLUSIONS: In the present administrative claims database study, no difference was found in the reoperation rate between ACDF and laminoplasty. ACDF resulted in fewer complications and readmissions compared with laminoplasty but was associated with greater costs. Additional prospective research is required to investigate the factors driving the higher costs of ACDF in this population and the long-term clinical outcomes.