Prediction of 5-year survival in soft tissue leiomyosarcoma using a machine learning model algorithm.

BACKGROUND AND OBJECTIVES: Leiomyosarcoma (LMS) is associated with one of the poorest overall survivals among soft tissue sarcomas. We sought to develop and externally validate a model for 5-year survival prediction in patients with appendicular or truncal LMS using machine learning algorithms. METHODS: The Surveillance, Epidemiology, and End Results (SEER) database was used for development and internal validation of the models; external validation was assessed using our institutional database. Five machine learning algorithms were developed and then tested on our institutional database. Area under the receiver operating characteristic curve (AUC) and Brier score were used to assess model performance. RESULTS: A total of 2209 patients from the SEER database and 81 patients from our tertiary institution were included. All models had excellent calibration with AUC 0.84-0.85 and Brier score 0.15-0.16. After assessing the performance indicators according to the TRIPOD model, we found that the Elastic-Net Penalized Logistic Regression outperformed other models. The AUCs of the institutional data were 0.83 (imputed) and 0.85 (complete-case analysis) with a Brier score of 0.16. CONCLUSION: Our study successfully developed five machine learning algorithms to assess 5-year survival in patients with LMS. The Elastic-Net Penalized Logistic Regression retained performance upon external validation with an AUC of 0.85 and Brier score of 0.15.

Increased Dislocation Rates After Total Hip Arthroplasty in Patients With Prior Isolated Sacroiliac Joint Arthrodesis.

BACKGROUND: While stiffness of the lumbosacral spine is a known predictor of instability following total hip arthroplasty (THA), little is known about the medical- and surgical-related outcomes following THA in patients who have prior isolated sacroiliac (SI) joint arthrodesis. METHODS: 197 patients who had a history of isolated SI joint arthrodesis who subsequently underwent elective primary THA for a diagnosis of osteoarthritis (THA-SI) from 2015 to 2021 were identified in a national administrative database. Using propensity score matching and logistic regression analyses, this cohort was compared to two groups of patients: patients who did not have any history of lumbar or SI arthrodesis and patients undergoing primary THA who had a history of lumbar arthrodesis without extension into the SI joint (THA-LF). RESULTS: The THA-SI group had a significantly higher incidence of dislocation (odds ratio 2.06, 95% confidence interval 1.04-4.04, P = .037) with no increased incidence of medical complications or other surgical complications when compared to patients without a history of SI or lumbar arthrodesis. There were no significant differences in any complications in THA-SI patients when compared to THA-LF patients. CONCLUSION: Patients who had prior isolated SI joint arthrodesis undergoing primary THA demonstrated a two-fold increased incidence of dislocation when compared to those who did not have prior SI arthrodesis, although the risk of complications in this population was similar to that observed in patients who had prior isolated lumbar spine arthrodesis.

Orthopedic Surgery Fellowship Directors: Trends in Demographics, Education, Employment, and Institutional Familiarity.

Background: Fellowship directors are assumed to be distinguished in orthopedics, but the traits and training that have enabled them to achieve their leadership positions have not been assessed. Purpose: We sought to identify common demographics, research output, and educational trends of fellowship directors in orthopedics, with an emphasis on racial, ethnic, and gender diversity. Methods: We conducted a literature review to identify published studies on fellowship directors in orthopedic surgery and found 4 cross-sectional studies of fellowship directors in spine, arthroplasty, pediatrics, and sports medicine subspecialties. Another 4 accredited orthopedic subspecialties and their fellowship directors were identified using the American College of Graduate Medical Education Public Accreditation Data System for 2020-2021 and national fellowship directories. Data endpoints included race/ethnicity, age, sex, residency and fellowship training institutions, year of fellowship completion, year of hire at current institution, year of fellowship directors appointment, and h-index. The demographics and educational backgrounds for listed fellowship directors were collected from curricula vitae (CVs). Results: Of the 537 fellowship directors identified among 8 orthopedic subspecialties, the average age was 52.9 ± 2.2 years, 5.6% (N = 30) were women, 79.1% (N = 406) were white, 12.5% (N = 64) were Asian American, 3.7% (N = 19) were African American, 2.9% (N = 15) were Middle Eastern, and 1.7% (N = 9) were Hispanic/Latino. Oncology 20% (N = 4) had the highest percentage of female fellowship directors; 37.6% (N = 202) of fellowship directors were at the same institution they trained at for residency or fellowship. Their average h-index was 18.6 ± 3.7. Conclusion: This study of fellowship directors in orthopedics found that they have a high research output and a high level of institutional familiarity. We identified a need for greater diversity in these leadership positions in both gender and race/ethnicity.

Predictors of Symptomatic Venous Thromboembolism in Patients with Soft Tissue Sarcoma in the Lower Extremity.

Orthopedic surgery and soft-tissue sarcoma (STS) both independently increase the risk of developing symptomatic venous thromboembolic events (SVTE), but there are no established risk factors or guidelines for how to prophylactically treat patients with STS undergoing surgery. The objectives of this study were to (1) identify the prevalence of SVTE in patients undergoing STS surgery, (2) identify risk factors for SVTE, and (3) determine the risk of wound complications associated with VTE prophylaxis. This retrospective study was conducted in a tertiary level, academic hospital. A total of 642 patients were treated for soft-tissue sarcoma in the lower extremity with follow up for at least 90 days for the development of SVTE such as deep venous thrombosis and pulmonary embolism. Multivariate logistic regression was used to identify predictors for these events by controlling for patient characteristics, surgical characteristics, and treatment variables, with significance held at p < 0.05. Twenty eight patients (4.36%) were diagnosed with SVTE. Multivariate analysis found six significant predictors ordered based on standardized coefficients: pre-operative (PTT) partial thromboplastin time (p < 0.001), post-operative PTT (p = 0.010), post-op chemotherapy (p = 0.013), metastasis at diagnosis (p = 0.025), additional surgery for metastasis or local recurrence (p = 0.004), and tumor size larger than 10 cm (p < 0.001). The risk of wound complications (p = 0.04) and infection (p = 0.017) increased significantly in patients who received chemical prophylaxis. Our study identifies risk factors for patients at increased risk of developing VTE. Further prospective research is necessary to identify which protocols would be beneficial in preventing SVTE in high-risk patients with a low profile of wound complications.

Improvement of postural stability and gait velocity after cervical decompression surgery in patients with cervical spondylotic myelopathy.

OBJECTIVE: Cervical spondylotic myelopathy (CSM) is a progressive degenerative condition that can lead to significant neurological deficits, including gait instability. Biomechanical alterations of gait and its various components are poorly understood. The goal of the current study was to determine how spatiotemporal gait parameters, as well as postural and dynamic stability, change after surgery in CSM patients. METHODS: A total of 47 subjects were included, with 23 test subjects and 24 controls. Baseline measurements were made for both cohorts. In the CSM cohort, repeat measurements were made at 3 and 6 months postoperatively. To record spatiotemporal and dynamic stability parameters, subjects performed walking trials over force plates on a 15-m runway. To assess postural stability, standing balance trials were conducted on a floor-mounted force plate. Three-dimensional motion analysis cameras and gait modeling software were used to quantify and visually represent results. Statistical analysis was completed using repeated-measures ANOVA and paired t-tests. Significance was set at p < 0.05. RESULTS: CSM patients had significantly increased gait velocity at the 6-month follow-up (mean 0.948 ± 0.248 m/sec/leg length) versus baseline (mean 0.852 ± 0.257 m/sec/leg length) (p = 0.039). The tilted ellipse area was significantly decreased at the 6-month follow-up compared with baseline (mean 979.8 ± 856.7 mm2 vs 598.0 ± 391.1 mm2, p = 0.018). Angular momentum excursion was not significantly different between baseline and the 3- and 6-month follow-ups. CONCLUSIONS: CSM patients displayed significant improvement in gait velocity and postural stability parameters after decompressive surgery. Dynamic stability parameters did not change significantly during the study period.

Presence and Severity of Mental Illness Is Associated With Increased Risk of Postoperative Emergency Visits, Readmission, and Reoperation Following Outpatient ACDF: A National Database Analysis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purpose was to compare rates of postoperative ED visits, readmission, and reoperation between patients with and without preexisting mental illness undergoing outpatient anterior cervical discectomy and fusion (ACDF). METHODS: A retrospective review of the Mariner Database was conducted on patients who underwent ACDF between 2010 and 2017. Exclusion criteria included same day revision surgery and patients with a history of spine infection, trauma, or neoplasm. Patients were grouped into 3 categories: those with existing history of anxiety and/or depression, those with severe mental illness, and those without any history of mental illness. Severe mental illness was defined as a combination of diagnosis including schizophrenia, bipolar disorder, and/or psychotic disorder. Outcome measures were analyzed by comparing groups using multivariate logistic regression. Significance was set at P < 0.05. RESULTS: Patients with anxiety/depression and patients with severe mental illness both had significantly increased risk of ED visits and readmission at 30-day and 90-day intervals. Compared to patients without mental illness, patients with severe mental illness (OR 1.93, P < 0.001) had significantly increased rates of reoperation at 90-days and 1-years postoperatively. Patients with anxiety/depression did not have increased rates of reoperation relative to patients without anxiety/depression at any time interval (P > 0.05). CONCLUSION: Anxiety/depression as well as more severe psychiatric disease such as Schizophrenia and Bipolar disorder were significantly associated with increased healthcare utilization following outpatient ACDF. Patients with preexisting mental illness undergoing outpatient ACDF should be carefully evaluated preoperatively and closely followed postoperatively to reduce risk of adverse events.

Venous Thromboembolic Events are Exceedingly Rare in Spinal Fusion for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Review of health care record database and determination of population statistics. OBJECTIVE: The purpose of this study was to quantify the incidence of clinically significant venous thromboembolic (VTE) events in patients undergoing spinal fusion surgery for adolescent idiopathic scoliosis (AIS) and to identify risk factors for VTE. SUMMARY OF BACKGROUND DATA: VTE is a serious complication that can cause disability and even death following surgery. Incidence of VTE following AIS surgery has not been well studied; the use of a national database allows the assessment of rare, yet important complications. MATERIALS AND METHODS: The PearlDiver Database was used to identify AIS patients who underwent primary instrumented spinal fusion between 2010 and 2020. Patient records were cross-referenced for documented VTEs within 30 and 90 postoperative days. Patients with nonidiopathic scoliosis were excluded. Logistic regression was used to evaluate risk factors for correlation with VTE events. RESULTS: Thirty-eight of 11,775 (0.323%) patients undergoing surgery for AIS developed a VTE complication within 90 postoperative days. Hypercoagulability [odds ratio (OR)=13.50, P <0.0001], spinal fusion involving 13+ vertebral levels (OR=2.61, P <0.0001), obesity (OR=1.30, P <0.005), and older (15-18 y) compared with younger adolescence (10-14 y) (OR=2.12, P <0.0001) were associated with VTE. Seven of 38 (18.4%) patients with a diagnosed thrombophilia experienced VTE. CONCLUSIONS: The incidence of clinically significant VTEs in pediatric patients following spinal fusion surgery for AIS is low with an incidence of 0.323%. Postoperative chemoprophylaxis in the general pediatric population is not indicated. Patients with obesity, those undergoing spinal fusion of 13 or more vertebrae, and adolescents 15-18 years old were found to have higher but still small risk of VTE following surgery. Further prospective studies are needed to validate the risk profile of patients with hypercoagulability and establish clinical guidelines for use of postoperative chemoprophylaxis in this cohort. LEVEL OF EVIDENCE: Level III.

Treatment of Hepatitis C Virus Prior to Posterior Lumbar Fusion: No Difference in Medical Outcomes or Reoperation.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To analyze and confirm the rates of postoperative complications of patients with hepatitis C virus (HCV) undergoing primary posterior lumbar fusion (PLF) and assess whether treatment of HCV before surgery reduces complications. BACKGROUND CONTEXT: HCV causes chronic disease, leading to increased risk of cirrhosis and chronic illness. Currently, there is a lack of research regarding whether the patient's HCV is a modifiable risk factor for postoperative complications after spinal procedures. METHODS: The Mariner database was utilized to find patients from 2010 to 2018 undergoing PLF with active follow-up for a year. Cases involving same-day revision procedures and patients with a history of spine, infection, trauma, human immunodeficiency virus, hepatitis B, or neoplasm were excluded. Patients with a history of HCV diagnosis were identified and further stratified whether they had prior treatment using the national drug codes for antiviral, interferons, or ribavirin. Patients with HCV were matched with those without respect to age, sex, and comorbidity of burden. Outcome measured included 90-day medical complications, infection, readmission, and 1-year reoperation. RESULTS: There were 2,129 patients with HCV and 10,544 patients in the matched control group who underwent primary PLF. Out of the 2,129 patients, 469 (22.0.%) were treated with HCV medications before surgery. Patients with prior history of HCV had a significantly increased risk of wound complications (4.4% vs. 3.2%, odds ratio 1.56, 95% confidence interval 1.24-1.96, P =0.009), and infection (7.7% vs. 5.7%, odds ratio 1.26, 95% confidence interval 1.07-1.53, P =0.009) within 90 days of surgery. Patients treated before surgery did not have a difference in major ( P =0.205) or minor medical complications ( P =0.681) after surgery. CONCLUSIONS: Patients with prior history of HCV are at increased risk for many complications after surgery; however, this risk factor does not seem to be modifiable as the treatment group did not experience any improvement in postoperative outcomes. LEVEL OF EVIDENCE: Level III.

Economic and educational disparities are associated with an increased risk of revision surgery following shoulder arthroplasty.

BACKGROUND: There is limited literature exploring how nonmedical factors such as social determinants of health (SDOHs) are associated with postoperative outcomes following shoulder arthroplasty. METHODS: A retrospective cohort review of the Pearl Diver Database was used to capture patients undergoing either primary anatomic total or reverse shoulder arthroplasty from the fourth quarter of 2015 to the third quarter of 2019 with at least 1 year of active longitudinal follow-up. Patients with proximal humeral fractures, stress fractures, or septic arthritis were excluded. The included patients were then divided into 2 cohorts based on the presence of current SDOHs or a history of SDOHs. The SDOH cohort comprised 4 non-mutually exclusive categories: economic, educational, social, and environmental disparities. Subsequently, a control cohort was matched at a 1:1 ratio to the SDOH cohort. Primary outcome measures were assessed using a logistic regression and consisted of the following 90-day postoperative complications: minor and major medical complications and infection. Emergency department (ED) visits and readmissions for any cause were also assessed. Additionally, the following 1-year outcomes were assessed: aseptic loosening, instability, and revision arthroplasty. Surgical costs and 90-day postoperative costs were collected using averaged insurance reimbursements for both the control and SDOH cohorts. RESULTS: There were 5190 patients in each cohort. Economic disparities made up the largest portion of the SDOH cohort (n = 4631, 89.2%), followed by social (n = 741, 14.3%), environmental (n = 417, 8.0%), and educational (n = 99, 1.9%) disparities. Compared with the control cohort, SDOHs were associated with an increased risk of major complications (2.3% vs. 1.4%; odds ratio [OR], 1.55; 95% confidence interval [CI], 1.29-1.87; P < .001), minor complications (5.7% vs. 3.8%; OR, 1.62; 95% CI, 1.21-1.95; P = .001), readmissions (4.3% vs. 2.8%; OR, 1.56; 95% CI, 1.26-1.84; P < .001), and ED visits (15.2% vs. 11.0%; OR, 1.45; 95% CI, 1.29-1.63; P < .001) within 90 days following surgery. Additionally, SDOHs were associated with an increased risk of aseptic loosening (1.1% vs. 0.6%; OR, 1.85; 95% CI, 1.20-2.65; P = .006), instability (4.0% vs. 2.2%; OR, 1.80; 95% CI, 1.43-2.28; P < .001), and ipsilateral revision (9.2% vs. 7.6%; OR, 1.24; 95% CI, 1.08-1.43; P < .001) at 1 year postoperatively compared with the control cohort. CONCLUSION: SDOHs are associated with increased rates of adverse outcomes following shoulder arthroplasty including revision surgery, ED visits, length of stay, and overall cost compared with matched controls without SDOHs. Specifically, economic and educational disparities are associated with increased rates of adverse outcomes following surgery including revision surgery, ED visits, length of stay, and overall cost.

Prognostic Factors Impacting Surgical Outcomes in Patients With Cervical Spondylotic Myelopathy.

The purpose of surgical decompression in patients who have CSM is to stop the progression of symptoms and hopefully improve function. It is critical to understand prognostic factors that affect the outcome. Factors intrinsic to the patient that can adversely affect outcomes include diabetes, older age, tobacco use, the presence of mental health disease, and obesity. MRI imaging findings of T2 hyperintensity and clinical duration and severity of symptoms is also associated with poorer outcomes. Patients should be counseled regarding the efficacy of decompressive procedures for CSM and given realistic expectations based on their unique biophysical profiles.

No Difference in Two-Year Revisions Between Hybrid Fusion and Two-Level Anterior Discectomy and Fusion: A National Database Study.

STUDY DESIGN: Retrospective Cohort. OBJECTIVE: This study utilized a large national database to compare two-year revision rates, in addition to complications and costs, of hybrid surgery (HS) compared to two-level anterior cervical discectomy and fusion (ACDF). METHODS: This study used the PearlDiver Mariner dataset selecting for patients aged 18 and older who had at least 90-day active longitudinal follow-up who underwent two-level ACDF or two-level Hybrid surgery (single level ACDF and single level CDA). Patients with prior spinal trauma, infection, cancer, or posterior fusion were excluded. Primary outcomes measures were 90-day major and minor medical complications, ED visits, readmissions, as well as two-year revisions. Patients were also assessed for postoperative dysphagia, incidental durotomy, vascular injury, 90-day surgical site, and implant complications. Additionally, hospitalization and postoperative costs were evaluated. RESULTS: There were 4570 two-level ACDF surgeries and 888 hybrid surgeries. After matching the cohorts, no statistical differences in demographics were found. There were no differences in reoperation rates at all measured time points nor 2-year complications. HS had a lower incidence of major (1.6% vs 3.1%, P = .003) and minor complications (3.0% vs 4.6%, P = .009) than ACDF. 90-day readmission was lower in the HS cohort (2.8% vs 4.2%), P = .024. HS was associated with reduced hospitalization costs -$2614 (-$3916 to -$904, P < .001). 3516 patients had ACDF, and 699 had HS with at least 2 years of follow-up. CONCLUSION: Hybrid surgery is a safe and effective surgical treatment for cervical disease in appropriately selected patients.

Predictors of reoperation after surgery for spinal epidural abscess.

BACKGROUND CONTEXT: Spinal epidural abscess is a rare but severe condition with high rates of postoperative adverse events. PURPOSE: The objective of the study was to identify independent prognostic factors for reoperation using two datasets: an institutional and national database. STUDY DESIGN/SETTING: Retrospective Review. PATIENT SAMPLE: Database 1: Review of five medical centers from 1993 to 2016. Database 2: The National Surgical Quality Improvement Program (NSQIP) was queried between 2012 and 2016. OUTCOME MEASURES: Thirty-day and ninety-day reoperation rate. METHODS: Two independent datasets were reviewed to identify patients with spinal epidural abscesses undergoing spinal surgery. Multivariate analyses were used to determine independent prognostic factors for reoperation while including factors identified in bivariate analyses. RESULTS: Overall, 642 patients underwent surgery for a spinal epidural abscess in the institutional cohort, with a 90-day unplanned reoperation rate of 19.9%. In the NSQIP database, 951 patients were identified with a 30-day unplanned reoperation rate of 12.3%. On multivariate analysis in the NSQIP database, cervical spine abscess was the only factor that reached significance for 30-day reoperation (OR=1.71, 95% CI=1.11-2.63, p=.02, Area under the curve (AUC)=0.61). On multivariate analysis in the institutional cohort, independent prognostic factors for 30-day reoperation were: preoperative urinary incontinence, ventral location of abscess relative to thecal sac, cervical abscess, preoperative wound infection, and leukocytosis (AUC=0.65). Ninety-day reoperation rate also found hypoalbuminemia as a significant predictor (AUC=0.66). CONCLUSION: Six novel independent prognostic factors were identified for 90-day reoperation after surgery for a spinal epidural abscess. The multivariable analysis fairly predicts reoperation, indicating that there may be additional factors that need to be uncovered in future studies. The risk factors delineated in this study through the use of two large cohorts of spinal epidural abscess patients can be used to improve preoperative risk stratification and patient management.

The Utilization of Postoperative Inpatient Ultrasound for Lower Extremity Deep Venous Thrombosis Following Total Hip Arthroplasty has Decreased Dramatically Over the Past Decade With No Obvious Negative Impact on Patient Care.

BACKGROUND: Surgeons are increasingly performing total hip arthroplasty (THA) in the outpatient setting. Lower lengths of stay (LOS) could result in fewer lower extremity ultrasounds for deep vein thromboses (DVT). The objective of this study was to evaluate the incidence of lower extremity ultrasounds ordered and positive DVT results in the immediate postoperative period. METHODS: All patients undergoing elective primary THA at an academic tertiary care center from January 2010 to February 2020 were included. Primary outcome of interest was incidence of postoperative DVT ultrasounds while inpatient and within 2 weeks following THA. Statistical analysis, including descriptive statistics and significance testing, was performed. RESULTS: A total of 3,665 patients were included, of which, 2.0% (N = 72) of patients received a lower extremity ultrasound while inpatient, with only 2 being positive (2.8%), for an overall positivity rate of 0.05% of the entire cohort. The incidence of postoperative inpatient ultrasounds decreased from 7.0% in 2010 to 0.3% in 2020 (P < .001) whereas, the incidence of ultrasounds at 2 weeks and 2-week positivity rate remained stable. LOS was identified as a risk factor for postoperative inpatient ultrasound (P < .001). CONCLUSIONS: Postoperative ultrasounds to evaluate for DVT are associated with a low yield and appear to be a consequence of reduced LOS in the hospital. Given the stable diagnosis rate of DVT at 2 weeks, our data suggests that the increasing trend toward outpatient arthroplasty will not result in missed opportunities to diagnose postoperative DVTs or lead to adverse outcomes and may provide benefit to patients by eliminating unnecessary testing. LEVEL III EVIDENCE: Retrospective cohort study.

Anterior cervical discectomy and fusion in patients with preexisting dementia: Increased medical complications, costs, and 90-day readmissions.

STUDY DESIGN: Retrospective-Cohort INTRODUCTION: Dementia is among the most common health concerns for the aging population, characterized by steep cognitive decline and subsequent loss of independence. Limited orthopedic literature examines the influence that dementia has on patients undergoing elective spinal surgeries. METHODS: Employing the PearlDriver Database, a study population consisting of patients who underwent primary elective ACDF with a prior diagnosis of dementia were selected using Internal Classification Disease-9 (ICD) and ICD-10 codes. Patients with a history of trauma, infection, or malignancy were excluded. Patients with dementia were compared to matched controls via logistical regression accounting for patient demographics, medical comorbidities and levels operated on. Patients were assessed for 90-day outcomes including medical complications, emergency department visits, readmissions, one-year reoperation, hospital length of stay (LOS) and total operative hospitalization costs, and 90-day postoperative cost. RESULTS: There were 4104 patients in the dementia group and 20,269 patients in the matched control group who underwent primary ACDF. Multivariate analysis showed that patients with dementia undergoing ACDF were associated with increased 90-day major and minor medical complications (p < 0.001). Patients with dementia were also associated with an increased risk of dysphagia (p < 0.001), 90-day ER visits(p < 0.001), 90-day readmissions(p < 0.001), and increased LOS(p < 0.001) following ACDF compared to the control group. Additionally, both total hospitalization costs and 90-day postoperative costs were higher in the dementia cohort(p < 0.001). CONCLUSION: Preoperative dementia diagnosis in patients undergoing ACDF is associated with increased number of readmissions, hospitalization and 90-day costs, and postoperative medical complications.

Penicillin Allergy in Spine Surgery: Increased Rates of Sepsis, Emergency Room Visits, and Readmission.

OBJECTIVE: To determine if a penicillin allergy is an independent risk factor for poor outcomes after anterior cervical discectomy and fusion (ACDF) and posterior lumbar fusion (PLF). METHODS: A retrospective database review was performed using the PearlDiver data set. The study population included all patients younger than 85 years who underwent elective PLF or ACDF with diagnosis of penicillin allergy using International Classification of Diseases codes. Study patients were compared with controls for 90-day complications and 1-year reoperation rates. A multivariate logistic regression was used to determine the independent effect of penicillin allergy on the postoperative outcomes. RESULTS: PLF cohort multivariate analysis showed that patients with a penicillin allergy had a significantly increased risk of sepsis (2.6% vs. 2.0%; P = 0.020), urinary tract infection (10.8% vs. 8.4%; P < 0.001), emergency room visits (27.3% vs. 20.2%; P < 0.001), and readmissions (9.6% vs. 6.4%; P < 0.001) within 90 days index of surgery. Similarly, the ACDF cohort multivariate analysis showed that a penicillin allergy was associated with an increased risk of sepsis (1.8% vs. 1.1%; P < 0.001), emergency room visits (27.2% vs. 20.7%; P < 0.001), and readmissions (6.8% vs. 5.6%; P = 0.003) within 90 days index of surgery. CONCLUSIONS: The present study found that a reported penicillin allergy is associated with an increase in sepsis, urinary tract infection, emergency room visit, and readmission postoperatively within 90 days after PLF and ACDF. The findings can help physicians provide patients with more comprehensive preoperative counseling in the setting of patient-reported penicillin allergy.

Treatment Decision Regret in Patients Who Develop Periprosthetic Joint Infection and Require Two-Stage Revision Surgery.

BACKGROUND: The decision to proceed with total joint arthroplasty (TJA) can be complex and requires an assessment of potential risks of surgery. Patients who experience the potentially devastating complication of periprosthetic joint infection (PJI) may have a poor outcome and wish they had never elected to have surgery. No study has examined decision regret related to the choice to pursue TJA in patients who develop PJI. METHODS: All patients who were treated for PJI with a two-stage revision at a tertiary academic medical center between 2010 and 2020 were surveyed. Ninety-six patients agreed to answer 12 questions concerning their understanding of their preoperative risk of infection and their level of regret with the decision to pursue index TJA. Patient regret was calculated using the Decision Regret Scale. RESULTS: Seventy-two percent of patients reported that their joint replacement and concomitant infection had a severe ongoing impact on their quality of life, although only 28% of respondents regretted their choice to undergo index TJA, and 65% would undergo TJA again. A higher Musculoskeletal Infection Society outcome stage (typically due to failed treatment) and lower understanding of joint infection were associated with a higher level of regret on the Decision Regret Scale (P < .001). CONCLUSION: Self-reported decisional regret was present in only 1 in 4 patients who underwent arthroplasty despite experiencing a devastating complication, and almost two-thirds of patients with PJI reported they would undergo primary TJA again. Patients who were more informed about infection before TJA experienced less regret when they subsequently developed PJI. LEVEL OF EVIDENCE: III.

Artificial Intelligence in Adult Spinal Deformity.

Artificial Intelligence is gaining traction in medicine for its ease of use and advancements in technology. This study evaluates the current literature on the use of artificial intelligence in adult spinal deformity.

Propensity Scored Analysis of Outpatient Anterior Lumbar Interbody Fusion: No Increased Complications.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim were to (1) evaluate differences in postoperative outcomes and cost associated with outpatient anterior lumbar interbody fusion (ALIF) compared with inpatient ALIF, and to (2) identify independent factors contributing to complications after outpatient ALIF. SUMMARY OF BACKGROUND: While lumbar fusion is traditionally performed inpatient, outpatient spinal surgery is becoming more commonplace as surgical techniques improve. METHODS: The study population included all patients below 85 years of age who underwent elective ALIF (CPT-22558). Patients were then divided into those who underwent single-level fusion and multilevel fusion using the corresponding additional level fusion codes (CPT-22585). These resulting populations were then split into outpatient and inpatient cohorts by using a service location modifier. To account for selection bias, propensity score matching was performed; the inpatient cohorts were matched with respect to the outpatient cohorts based on age, sex, and Charlson Comorbidity Index. Statistical significance was set at P<0.05 and the Bonferroni correction was used for each multiple comparison (P<0.004). RESULTS: Patients undergoing outpatient procedure had decreased rates of medical complications following both single-level and multilevel ALIF. In addition, age above 60, female sex, Charlson Comorbidity Index>3, chronic obstructive pulmonary disease, diabetes mellitus, coronary artery disease, hypertension, and tobacco use were all identified as independent risk factors for increased complications. Finally, the cost of outpatient ALIF was $12,013 while the cost of inpatient ALIF was $27,271 (P<0.001). CONCLUSION: The findings add to the growing body of literature advocating for the utilization of ALIF in the outpatient setting for a properly selected group of patients. LEVEL OF EVIDENCE: Level IV.

Postoperative Outcomes Following Posterior Lumbar Fusion in Patients With Multiple Sclerosis.

SUMMARY OF BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory disease that can cause physical and neurological dysfunction. Patients with MS are living longer and undergoing more orthopedic procedures, but the risk of patients with MS undergoing posterior lumbar fusion (PLF) has not been studied in literature before. OBJECTIVE: This study aims to (1) analyze the rates of postoperative complications of MS patients undergoing primary PLF and (2) analyze the economic burden associated with these surgeries in the MS population compared with patients without MS. METHODS: A retrospective review of the Medicare database was conducted on all patients who underwent PLF and/or posterior lumbar interbody fusion between the years of 2006 and 2013. Cases involving same-day anterior or revision procedures and patients with a history of spine, infection, and trauma, or neoplasm were excluded from the study. Demographics, comorbidities, 90-day postoperative complications, cost, and length of stay were calculated. All outcomes of interest were analyzed using multivariate logistic regression, adjusting for age, sex, and comorbidity burden. Significance was defined as P-value <0.05. RESULTS: There were 2363 patients with MS and 23,569 matched controlled patients. We found a significant increase in the risk of sepsis [odds ratio (OR)=1.85, P=0.034], urinary tract infection (OR=1.89, P<0.001), deep vein thrombosis (OR=1.4, P=0.044), 90-day emergency room visit (OR=1.14, P=0.027), and 90-day readmissions (OR=1.20, P=0.011) compared with patients without a history of MS. Patients with MS also incurred $4379 extra in total hospital charge, a $1679 increase in the cost of hospitalization, and an increase in length of stay (4.05 vs. 3.61, P<0.001). CONCLUSIONS: A diagnosis of MS is associated with a significant increase in postoperative complications and higher costs after hospitalization. It is imperative for physicians to understand the risk factors of patients undergoing PLF and/or posterior lumbar interbody fusion with MS to better counsel them about postoperative complications before surgery. LEVEL OF EVIDENCE: Level III.