Trends in gastric surgery operative experience among general surgery residents in the United States: A nationwide retrospective analysis.

BACKGROUND: Gastric surgery is a crucial component of general surgery training. However, there is a paucity of high-quality data on operative volume and the diversity of surgical procedures that general surgery residents are exposed to. METHODS: We conducted a retrospective analysis of operative case logs of all general surgery residents graduating from the American College of Graduate Medical Education-accredited program from 2009 to 2022. Data on the mean number of gastric procedures, including the mean in each subcategory, were retrieved. A Mann-Kendall trend test was used to investigate trends in operative volume. RESULTS: Between 2009 and 2022, the mean overall logged gastric procedures rose significantly (τ = 0.722, P < .001) from 36.2 in 2009 to 49.2 in 2022 (35.9% increase). The most substantial growth was seen in laparoscopic gastric reduction for morbid obesity (mean 1.9 in 2017 to 19 in 2022; τ = 0.670, P = .009). A statistically significant increase was also seen in laparoscopic partial gastric resections, repair of gastric perforation, and "other major stomach procedures" (P < .05 for all comparisons). Open gastrostomy, open partial gastric resections, and open vagotomy all significantly decreased (P < .05 for all comparisons). There was no significant change in the volume of laparoscopic gastrectomy, total gastric resections, and non-laparoscopic gastric reductions for morbid obesity (P > .05 for all comparisons). CONCLUSION: There has been a substantial increase in the volume of gastric surgery during residency over the past 14 years, driven mainly by an increase in laparoscopic gastric reduction. However, there may still be a need for further gastric surgical training to ensure well-rounded general surgeons.

Operative Experience of Esophageal Surgery among General Surgery Residents in the United States: An Analysis of ACGME Operative Case Logs.

INTRODUCTION: Esophageal surgery is an essential component of general surgery training and encompasses several types of cases that are logged by general surgery residents. There is a scarcity of data on the quality and volume of esophageal surgery experience during surgical residency in the United States. We analyzed trends for 9 different esophageal procedure categories logged by residents in the United States, with the aim to identify areas for improvement in training. METHODS: We conducted a retrospective analysis of operative case logs of all general surgery residents graduating from programs accredited by the ACGME over a fourteen-year period from 2009 to 2023. Data on mean esophageal cases reported by graduates, including mean in each procedure subcategory were retrieved. Cases were categorized as either surgeon chief or surgeon junior for each procedure category. Mann-Kendall trend test was used to obtain tau statistics and p-value for trends in mean operative surgical volume for the total number of cases in each operative category over the study period. Trends in surgeon chief and surgeon junior cases were also investigated for each operative category. RESULTS: The mean number of all esophageal procedures performed per resident during their training increased significantly from 10.5 in 2009 to 16 in 2022 (τ = 0.833, p < 0.001). This trend observed among all esophageal procedures during this 14-year study can be largely attributed to the steady increase in the number and proportion of laparoscopic esophageal antireflux procedures performed (τ = 0.950, p < 0.001). Additionally, esophagectomy procedures had a statistically significant, but modest, increase during the study period (τ = 0.505, p = 0.023), from a mean of 1 case during training in 2009 to a peak of 1.3 in 2020. Although the general trend of esophagus procedures increased during the study period, most categories (7 out of 9) either decreased or did not significantly change. Esophagogastrectomy volume decreased significantly by 30%, from 1 per resident during their training in 2009 to 0.7 in 2022 (τ = -0.510, p = 0.018), esophageal diverticulectomy procedures decreased by 50% from 0.2 to 0.1 (τ = -0.609, p = 0.009), and operations for esophageal stenosis decreased by 75% from 0.4 to 0.1 (τ = -0.734, p = 0.001). Mean number of esophageal bypasses (τ = -0.128, p = 0.584), repair of perforated esophageal disease (τ = -0.333, p = 0.156), and other major esophagus procedures (τ = 0.416, p = 0.063) did not significantly change. CONCLUSION: The operative volume of esophageal surgery that general surgery residents in the United States are exposed to has significantly risen over the past 14 years, largely driven by the increase in laparoscopic antireflux procedures. However, given the recent advances and the resultant heterogeneity in both esophageal surgery, the increase in resident operative volume is still inadequate to ensure the training of safe and adept esophageal surgeons, necessitating postresidency specialized training for trainees interested in esophageal surgery.

Predictors of Length of Hospital Stay After Reduction of Internal Hernia in Patients With a History of Roux-en-Y Gastric Bypass.

BACKGROUND: Postoperative internal hernias after Roux-en-Y gastric bypass (RYGB) have an incidence of 2%-9% and are a surgical emergency. Evidence on factors associated with length of stay (LOS) after emergent internal hernia reduction in RYGB patients is limited. METHODS: This is a retrospective review of patients who underwent internal hernia reduction after RYGB at our tertiary care center over a 5 year period from 2015 to 2020. Demographics, comorbidities, and intra- and postoperative hospital course were collected. Univariate and multivariate linear regressions were used to investigate factors associated with LOS. RESULTS: We identified 38 patients with internal hernia after RYGB. These patients with mean age 44.1 years were majority female (71.1%) and white race (60.5%). Of the 24 patients where the RYGB was done at our institution, the mean RYGB to IH interval was 43 months. Petersen's defect (57.8%) followed by jejuno-jejunal mesenteric defect (31.6%) were the most common locations for IH. Both Petersen's and jejuno-jejunal mesenteric hernias were found in 4 cases (10.5%). Revision of bypass and small bowel resection were required in 13.2% and 5.3% of cases, respectively. The median (interquartile range) length of stay (LOS) was 2 days. On the multivariate analysis, male sex (P = .019), conversion to exploratory laparotomy (P = .005), and resection of small bowel (P < .001) were independent risk factors for increased LOS. CONCLUSION: The most common location of IH after RYGB is Petersen's defect, followed by jejuno-jejunal mesenteric defect. LOS was significantly associated with male sex, exploratory laparotomy, and resection of small bowel.

Marijuana and Vascular Disease: A Review.

Marijuana use is common and increasing due to decriminalization, legalization, and expansion of medical use. As a result, the proportion of vascular patients with marijuana is also expected to increase, raising questions if cannabis use affects the incidence and outcomes of vascular disease. Active ingredients of cannabis have been shown to interact with receptors found on vascular endothelium, promoting oxidative stress and endothelial dysfunction. However, current clinical studies have yet to demonstrate a relationship between marijuana use and atherosclerosis. Nonetheless, cannabis arteritis is a rare condition where cannabis is hypothesized to induce vascular inflammation. Future research with high-quality studies is needed to clarify the impact of marijuana use on vascular diseases.

The Utility of the Validated Intraoperative Bleeding Scale in Thoracolumbar Spine Surgery: A Single-Center Prospective Study.

STUDY DESIGN: Prospective, single-center study. OBJECTIVE: To evaluate the clinical relevance of the validated intraoperative bleeding severity scale (VIBe) in thoracolumbar spine surgery. METHODS: Adult patients aged 18 through 88 undergoing elective decompression, instrumentation, and fusion of the thoracolumbar spine were prospectively enrolled after informed consent was provided and written consent was obtained. Validated intraoperative bleeding severity scores were recorded intraoperatively. Univariate analysis consisted of Student T-tests, Pearson's χ2 Tests, Fisher's Exact Tests, linear regression, and binary logistic regression. Multivariable regression was conducted to adjust for baseline characteristics and potential confounding variables. RESULTS: A total of N = 121 patients were enrolled and included in the analysis. After adjusting for confounders, VIBe scores were correlated with an increased likelihood of intraoperative blood transfusion (ß = 2.46, P = .012), postoperative blood transfusion (ß = 2.36, P = .015), any transfusion (ß = 2.49, P < .001), total transfusion volume (ß = 180.8, P = .020), and estimated blood loss (EBL) (ß = 409, P < .001). Validated intraoperative bleeding severity scores had no significant association with length of hospital stay, 30-day readmission, 30-day reoperation, 30-day emergency department visit, change in pre- to post-op hemoglobin and hematocrit, total drain output, or length of surgery. CONCLUSION: The VIBe scale is associated with perioperative transfusion rates and EBL in patients undergoing thoracolumbar spine surgery. Overall, the VIBe scale has clinically relevant meaning in spine surgery, and shows potential utility in clinical research. LEVEL OF EVIDENCE: Level II.

Trends in Surgical Critical Care Fellowship Match: An Analysis of National Resident Matching Program Data.

INTRODUCTION: Surgical Critical Care (SCC) fellowship applications are made through March-July the year prior to the fellowship, while the match process takes place through the National Resident Matching Program (NRMP). There is paucity of high quality data on matching trends in SCC fellowship in the United States. METHODS: We conducted a retrospective cohort study of all applicants in the SCC match over a period of fifteen years (2009-2023). Publicly published data about the SCC fellowship match were retrieved from the NRMP online portal. Mann Kendall trend test was used to obtain a Tau statistic and p-values for temporal trends over time. Chi-square test was used to investigate association between categorical variables. RESULTS: From 2009 to 2023, the number of SCC fellowship positions increased from 143 to 340 (138% increase) while the number of applicants rose from 95 to 289 (204% increase). The overall match rate for applicants significantly rose from 89.5% to 93.4% (7.7% increase; t = 0.600, p = 0.002). The percentage of positions filled also increased from 59.4% in 2009 to 79.4% in 2023. The match rate over the past five years (2019-2023) was 90.8%. US-MD applicants had a significantly higher 94.8% match rate throughout the study period than non-US MD applicants (94.8% vs. 87.3%, p<0.001). While the match rate for US-MD applicants has stayed consistent from 2009 to 2023 (τ = 0.371, p = 0.054), the match rate for non-US-MD applicants increased from 77.3% in 2009 to 86.9% in 2023 (τ = 0.771, p<0.001). CONCLUSION: SCC fellowship continues to grow with more positions and applicants. Match rates into SCC fellowships have increased over the past fifteen years, primarily helping non-US MDs match successfully.

Colon and Rectal Surgery Fellowship Applicant and Matching Trends in the United States: An Analysis of National Resident Matching Program Data.

BACKGROUND: Colon and Rectal Surgery fellowships are training programs that aim to train surgeons in the management of small bowel, colon, rectal, and anal pathologies. OBJECTIVE: We investigated trends in Colon and Rectal Surgery fellowship match to help applicants anticipate future fellowship application cycles. DESIGN: This was a retrospective cohort study of applicants in the Colon and Rectal Surgery match from 2009 to 2023. Proportion of positions filled, match rates, and rank-order lists were collected. The impact of US-MD, non-US-MD, and DO status on match rate was assessed. We used the Mann Kendall trend test to obtain tau statistic and P-value for temporal trends over time, while associations between categorical variables were investigated by a chi-square test. RESULTS: Fellowship programs increased from 43 to 67, positions increased from 78 to 110, and number of applicants rose from 113 to 135. Nearly all positions were filled from 2009 to 2023 (range: 96.3%-100%). The overall match rate fluctuated between 67.3% and 80.7%. The match rate over the past 5 years was 72.0%. The match rate for US-MDs was 80.0%, while non-US-MDs had a 56.2% match rate. The percentage matching at each rank were first choice 28.0%, second choice 10.4%, third choice 6.9%, and fourth choice or lower 23.5%. CONCLUSION: Despite an increase in Colon and Rectal Surgery fellowship positions, the overall match rate has not changed significantly over the years, mainly as a result of increased applicants.

Temporal trends in mortality location in patients with anal cancer in the USA: an analysis of the National Center for Health Statistics mortality data.

OBJECTIVES: Investigate trends in where patients died of anal cancer in the USA. METHODS: Retrospective cohort study using the US National Center for Health Statistics Wide-Ranging ONline Data for Epidemiologic Research platform from 2003 to 2020; all patients with death certificates listing anal cancer as the underlying cause of death in the USA. Main outcome measure of location of patient death: inpatient facility, home, hospice, nursing home/long-term care facility and other. RESULTS: There were a total of 16 296 deaths with anal cancer as the underlying diagnosis during the study period. The crude rate increased from 0.191 per 100 000 deaths in 2003 to 0.453 per 100 000 deaths in 2020. Over the study period, 22.4% of patient deaths occurred in inpatient facilities, 44.9% at home, 12.2% at hospice facilities and 13.1% at nursing homes/long-term care facilities. The percentage of deaths occurring in hospice facilities increased from 1.0% to 13.3% during the study period. Deaths at home also increased from 42.7% in 2003 to 55.8% in 2020. Meanwhile, inpatient deaths decreased from 33.5% in 2003 to 14.4% in 2020. CONCLUSIONS: There has been a significant increase in the proportion of patients with anal cancer dying at home or hospice from 2003 to 2020.

FLOSEAL Versus SURGIFLO in Lumbar Surgery: Similar Outcomes, Different Costs in a Matched Cohort Analysis.

OBJECTIVE: Flowable gelatin-based matrices with thrombin for hemostatic control are commercially available as Floseal (Baxter International Inc.) and Surgiflo (Ethicon Inc.). The objective of this study is to compare the rate of blood transfusions following the use of Floseal and Surgiflo in lumbar spine surgery. METHODS: Elective lumbar spine surgery patients between September 2019 and March 2021 were identified via CPT codes. Floseal 10 mL (N=102) and Surgiflo matrix 8 mL (N=108) cohorts excluded those younger than 18 years or those who underwent surgeries for infection, trauma, or tumor. The primary outcome was blood transfusion. Surgical complexity was controlled using the Surgical Invasiveness Index and Adult Spinal Deformity Invasiveness Score. The 1:1 propensity score matching was performed using demographic information, Surgical Invasiveness Index, Adult Spinal Deformity Invasiveness Score, and tranexamic acid use. RESULTS: A total of 77 Floseal patients were propensity score matched with 77 Surgiflo patients. There was no difference in the rate of blood transfusion (p=0.441). There was also no difference in operative time, estimated blood loss, or postoperative hemoglobin levels. The Surgiflo cohort used more units per surgery (p=0.004) and cost $102.45 more per surgery. Switching to Floseal saves $102,450 per year per 1000 surgeries. CONCLUSIONS: There was no difference in transfusion rates between using Floseal or Surgiflo for lumbar spine surgery. Surgiflo had higher usage per surgery and costs than Floseal.

Retrospective Analysis of Causes and Risk Factors of 30-Day Readmission After Spine Surgery for Thoracolumbar Trauma.

STUDY DESIGN: Retrospective Case Series. OBJECTIVE: This study aims to evaluate readmission rates, risk factors, and reason for unplanned 30-day readmissions after thoracolumbar spine trauma surgery. METHODS: A retrospective chart review was conducted for patients undergoing operative treatment for thoracic or lumbar trauma with open or minimally invasive surgical approach at a Level 1 urban trauma center. Patients were divided into two groups based on 30-day readmission status. Reason for readmission, reoperation rates, injury type, trauma severity, and incidence of polytrauma were compared between the two groups. RESULTS: A total of 312 patients, 69.9% male with an average age of 47 ± 19 years were included. The readmitted group included 16 patients (5.1%) of which 9 (56%) were readmitted for medical complications and 7 for surgical complications. Wound complications (31.3% of readmissions) were the most common cause of readmission, followed by non-wound related sepsis (18.9% of readmissions). A total of 6 patients (37.5%) required reoperation; 2 instrumentation failures underwent revision surgery, and 4 wound complications underwent irrigation and debridement. Patients with higher Injury Severity Scale (ISS) were more likely to be readmitted (27.8% vs 22.1%, P = .045). Concomitant lower limb surgery increased odds of readmission (OR, 4.40; 95% CI, 1.10-17.83; P = .037). CONCLUSION: Spine trauma 30-day readmission rate was 5.1%, comparable to those reported in the elective spine surgery literature. Readmitted patients were more likely to sustain concomitant operative lower limb trauma. Wound complications were the most common cause of readmission, and almost half of the patients were readmitted due to surgery-related complications.

Intraoperative Sensory Signals Predict Prognosis for Patients with Traumatic Cervical Spinal Cord Injury.

OBJECTIVE: In patients with traumatic cervical spinal cord injury (tCSCI), the potential role of intraoperative neuromonitoring as a prognostic tool has been insufficiently studied. This study aimed to determine if detectable signals during intraoperative neuromonitoring portend a greater likelihood of recovery for patients with tCSCI. METHODS: Patients who underwent decompression and surgical fixation following tCSCI were retrospectively reviewed through previously prospectively collected data from the Surgical Timing in Acute Spinal Cord Injury Study. Improvement in American Spinal Injury Association (ASIA) motor score and ASIA Impairment Scale grade conversion rates at final follow-up were compared between patients with detectable intraoperative neuromonitoring somatosensory evoked potential (SSEP) signals and those without detectable signals. RESULTS: Forty-nine patients had intraoperative neuromonitoring. Patients with incomplete tCSCI had detectable lower extremity SSEPs more often than patients with complete tCSCI (56.3% vs. 23.5%, P = 0.028). There was no difference in detectable upper extremity SSEPs between complete and incomplete tCSCI (65.6% vs. 58.8%, P = 0.638). Of the 17 patients with complete tCSCI, patients with detectable lower extremity SSEPs had ASIA motor scores similar to the nondetectable cohort on admission (21.5 vs. 16.2, P = 0.609) but higher ASIA motor scores at final follow-up (57.5 vs. 27.1, P = 0.041). Of the 32 patients with incomplete spinal cord injury, there was no difference in grade conversion or motor scores between detectable and nondetectable SSEP cohorts. CONCLUSIONS: The presence of upper extremity SSEP signals in patients who present with complete tCSCI portends greater improvement in ASIA motor scores and likelihood of American Spinal Injury Association Impairment Scale grade conversion at final follow-up.

Open vs Percutaneous Pedicle Instrumentation for Kyphosis Correction in Traumatic Thoracic and Thoracolumbar Spine Injuries.

OBJECTIVES: Percutaneous pedicle instrumentation (PPI) has been used for the treatment of thoracic and thoracolumbar (TL) trauma. However, the ability of PPI to correct significant post-traumatic kyphosis requires further investigation. The objective of this study is to compare the amount of kyphosis correction achieved by PPI vs the traditional open posterior approach in patients presenting with significant kyphotic deformity following traumatic thoracic and TL spine injuries. METHODS: Following Institutional Review Board approval, patients who underwent surgery for thoracic (T1-T9) or TL (T10-L2) fractures with at least 15° of focal kyphosis in a 5-year period were included in this study. Patients were separated into 2 cohorts based on surgical technique: traditional open posterior approach and minimally invasive PPI. Kyphosis correction was measured using Cobb angle 1 vertebrae above and 1 below the level of injury on sagittal preoperative computed tomography image, immediate and follow-up postoperative upright lateral radiographs. Initial degree of correction and loss of correction at the final follow-up were compared. RESULTS: Of 91 patients included, 65 (71%) underwent open surgery and 26 (29%) underwent PPI. Open patients had 11° (95% CI, 9°-13°) of immediate correction compared with 11° (95% CI, 6°-15°) for PPI (P = 0.81). Follow-up data were available for 70 patients with a median of 105.5 days. Both groups had 1° (95% CI, 0°-2°) of loss of correction at follow-up (P = 0.82). Regardless of surgical technique, obesity (>30 kg/m2) and AO type-A compression fractures had significantly less correction. For each unit of body mass index, there was a 0.75° decrease in correction achieved (P < 0.0001). Other factors did not influence the degree of correction. CONCLUSIONS: PPI techniques provide equivalent postoperative angular correction and maintenance of correction compared with open surgery in thoracic and TL trauma patients. CLINICAL RELEVANCE: This study provides evidence for spine surgeons to utilize either technique for treating significant traumatic kyphotic deformity. LEVEL OF EVIDENCE: Therapeutic 3.

Predicting Length of Stay After Thoracolumbar Trauma: A Single-Center, Retrospective Analysis.

BACKGROUND: Length of stay (LOS) is a meaningful outcome measure for more efficient and effective quality of care. However, algorithms to predict LOS have yet to be created for patients who undergo surgical management for traumatic spinal fractures. OBJECTIVES: The objectives of this study were to (1) identify preoperative, perioperative, and postoperative factors associated with increased LOS and (2) create predictive formulas to estimate LOS in thoracolumbar trauma patients who undergo surgical correction. METHODS: This is a retrospective case series of 196 patients operated for thoracolumbar spine trauma from January 2012 to December 2017 at a level 1 trauma and academic institution. Bivariate analysis between LOS and various preoperative, perioperative, and postoperative factors was conducted to identify significant associations. Multivariate analysis was conducted to create models capable of predicting LOS. RESULTS: LOS was significantly associated with various preoperative (eg, Charlson Comorbidity Index, Glasgow Coma Scale [GCS], injury severity score), operative (eg, length of surgery, number of instrumented segments, surgical technique), and postoperative variables (eg, complications, discharge location). Multivariate analysis of preoperative variables identified 5 significant independent predictors that could predict LOS with strong correlation with observed LOS (ρ = 0.63). With all variables considered, multivariate analysis identified 8 variables (GCS, American Society of Anesthesiologists score, neurological status, polytrauma, packed red blood cell transfusion, number of unique postoperative complications, skin complications, and discharge facility) that could predict LOS with strong correlation (ρ = 0.80). CONCLUSIONS: Various preoperative, perioperative, and postoperative factors are significantly associated with LOS in traumatic thoracolumbar spine patients. We developed models with good predictive capacity for LOS. If validated, these models should help in risk stratifying patients for increased LOS and consequently improve perioperative patient counseling. CLINICAL RELEVANCE: This article contributes to identifying and predicting patients who are high risk for extended LOS after traumatic thoracolumbar injuries.

Similar Accuracy of Surgical Plans After Initial In-Person and Telemedicine Evaluation of Spine Patients.

OBJECTIVE: The aim of this study was to compare accuracy of surgical plans generated from in-person and telemedicine evaluations and assess the reasons for surgical plan changes between initial evaluation and surgery. The secondary objective was to assess the effect of changes in surgical planning on postoperative outcomes. METHODS: In this retrospective cohort study, consecutive patients who were evaluated as new patients by orthopaedic spine faculty between 2019 and 2021 were divided by appointment type: telemedicine (n = 39) and in-person (n = 92). Patients were included if the surgeon documented a definitive surgical plan at the initial visit. The primary outcome was change in surgical plan from initial assessment to actual procedure performed. RESULTS: There was no significant difference in the accuracy of initial surgical plans between the telemedicine and in-person cohorts (79.5% vs. 82.6%, P = 0.673). The most common modification in the surgical plan (79%) was change in the number of operated levels, of which 18 of 19 patients had 1 added operated level. Less common reasons were change in approach (13%) and change in procedure (8%). Patients with changes to their surgical plan experienced longer length of stay (3.1 vs. 2.0 days, P = 0.027) than patients with consistent surgical plans. CONCLUSIONS: Telemedicine and in-person evaluations generated similarly accurate surgical plans. Changes to the initial surgical plans most often involved adding operative levels. Our findings show that telemedicine visits are an acceptable option for preoperative assessment to generate surgical plans; however, further research is needed.

Postoperative outcomes of minimally invasive pedicle screw fixation for treatment of unstable pathologic neoplastic fractures.

STUDY DESIGN: Retrospective Case Series. OBJECTIVES: Minimally invasive techniques have emerged as a useful tool in the treatment of neoplastic spine pathology due to decrease in surgical morbidity and earlier adjuvant treatment. The objective of this study was to analyze outcomes and complications in a cohort of unstable, symptomatic pathologic fractures treated with percutaneous pedicle screw fixation (PPSF). METHODS: A retrospective review was performed on consecutive patients with spinal stabilization for unstable pathologic neoplastic fractures between 2007 and 2017. Patients who underwent PPSF through a minimally invasive approach were included. Surgical indications included intractable pain, mechanical instability, and neurologic compromise with radiologic visualization of the lesion. RESULTS: 20 patients with mean Tomita Score of 6.3 ± 2.1 points [95% CI, 5.3-7.2] were treated with constructs that spanned a mean of 4.7 ± 1.4 [95% CI, 4.0-5.3] instrumented levels. 10 (50%) patients were augmented with vertebroplasty. Majority of patients (65%) had no complications during their hospital stay and were discharged home (60%). Four patients received reoperation: two extracavitary corpectomies, one pathologic fracture at a different level, and one adjacent segment disease. CONCLUSION: Minimally invasive PPSF is a safe and effective option when treating unstable neoplastic fractures and may be a viable alternative to the traditional open approach in select cases. LEVEL OF EVIDENCE: 4.

Outpatient versus inpatient total shoulder arthroplasty: A cost and outcome comparison in a comorbidity matched analysis.

BACKGROUND: Previous studies comparing total and reverse shoulder arthroplasty (TSA/RSA) are subject to surgeon selection bias. This study objective is to compare the outcomes and cost of outpatient TSA/RSA to inpatient TSA/RSA. METHODS: 108,889 elective inpatient and outpatient TSA/RSA from Medicare claims data (2016-2018). 90-day readmission and total 90-day costs were compared following propensity score matching. RESULTS: Younger and healthier patients are receiving outpatient TSA/RSA. Outpatient TSA/RSA was associated with fewer 90-day readmissions (OR 0.48 CI 0.38-0.59, p < 0.001) and lower 90-day costs (-20.1% CI -19.1%; -21.1%, p < 0.001). CONCLUSIONS: Outpatient TSA/RSA surgery offers lower complication rates and total costs. LEVEL OF EVIDENCE: III.

Automated Measurement of Lumbar Lordosis on Radiographs Using Machine Learning and Computer Vision.

STUDY DESIGN: Cross sectional database study. OBJECTIVE: To develop a fully automated artificial intelligence and computer vision pipeline for assisted evaluation of lumbar lordosis. METHODS: Lateral lumbar radiographs were used to develop a segmentation neural network (n = 629). After synthetic augmentation, 70% of these radiographs were used for network training, while the remaining 30% were used for hyperparameter optimization. A computer vision algorithm was deployed on the segmented radiographs to calculate lumbar lordosis angles. A test set of radiographs was used to evaluate the validity of the entire pipeline (n = 151). RESULTS: The U-Net segmentation achieved a test dataset dice score of 0.821, an area under the receiver operating curve of 0.914, and an accuracy of 0.862. The computer vision algorithm identified the L1 and S1 vertebrae on 84.1% of the test set with an average speed of 0.14 seconds/radiograph. From the 151 test set radiographs, 50 were randomly chosen for surgeon measurement. When compared with those measurements, our algorithm achieved a mean absolute error of 8.055° and a median absolute error of 6.965° (not statistically significant, P > .05). CONCLUSION: This study is the first to use artificial intelligence and computer vision in a combined pipeline to rapidly measure a sagittal spinopelvic parameter without prior manual surgeon input. The pipeline measures angles with no statistically significant differences from manual measurements by surgeons. This pipeline offers clinical utility in an assistive capacity, and future work should focus on improving segmentation network performance.

Can C7 Slope Be Used as a Substitute for T1 Slope? A Radiographic Analysis.

STUDY DESIGN: Retrospective radiographic study. OBJECTIVES: T1 slope is an important parameter of sagittal spinal balance. However, the T1 superior endplate can be difficult to visualize on radiographs due to overlying anatomical structures. C7 slope has been proposed as a potential substitute for T1 slope when the T1 superior endplate is not well visualized. The objective of this study was 2-fold: (1) to assess the correlation between C7 and T1 slopes on upright cervical spine radiographs and (2) to evaluate the interrater reliability of C7 slope. METHODS: Cervical spine radiographs taken between December 2017 and June 2018 at a single institution were reviewed. Two observers measured upper C7 slope, lower C7 slope, and T1 slope. The correlations between upper and lower C7 slope and T1 slope were evaluated, and linear regression analyses were performed. Interrater reliability of C7 slope was also assessed. RESULTS: In this cohort of 152 patients, there was a strong correlation between upper C7 slope and T1 slope (r = 0.91, P < .001), as well as between lower C7 slope and T1 slope (r = 0.90, P < .001). T1 slope could be estimated from the linear regression equation, T1 slope = 0.87 × C7 slope + 7, with an overall model fit of R 2 = 0.8. There was strong interrater reliability for upper (intraclass correlation coefficient [ICC] = 0.95, P < .001) and lower C7 slope (ICC = 0.96, P < .001). CONCLUSIONS: Both the upper and lower C7 slope are strongly correlated with T1 slope and can be used as a substitute to estimate T1 slope when the superior endplate of T1 is not well visualized.

Postoperative Complications Associated With Metabolic Syndrome Following Adult Spinal Deformity Surgery.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The objective of this study was to examine the effect of metabolic syndrome on 30-day postoperative complications following corrective surgery for the adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: Metabolic syndrome has been shown to increase the risk of cardiovascular morbidity and mortality. Few studies have examined the effect of metabolic syndrome on patients with ASD undergoing surgery. MATERIALS AND METHODS: We performed a retrospective cohort study of patients who underwent spinal fusion for ASD. Patients were divided into 2 groups based on the presence or absence of metabolic syndrome, which was defined as a combination of hypertension, diabetes mellitus, and obesity. Baseline patient characteristics and operative variables were compared between the 2 groups. We also compared the incidence of 30-day postoperative complications between the 2 groups. A multivariable regression analysis was then performed to identify 30-day postoperative complications that were independently associated with metabolic syndrome. RESULTS: A total of 6696 patients were included with 8.3% (n=553) having metabolic syndrome. Patients with metabolic syndrome were more likely to have renal comorbidity (P=0.042), bleeding disorder (P=0.011), American Society of Anesthesiology classification ≥3 (P<0.001), and undergo a long fusion (P=0.009). Patients with metabolic syndrome had higher rates of 30-day mortality (P=0.042), superficial surgical site infection (P=0.006), sepsis (P=0.003), cardiac complications (P<0.001), pulmonary complications (P=0.003), pulmonary embolism (P=0.050), prolonged hospitalization (P=0.010), nonhome discharge (P=0.007), and reoperation (P=0.003). Metabolic syndrome was an independent risk factor for cardiac complications [odds ratio (OR)=4.2; 95% confidence interval (CI): 1.7-10.2; P=0.001], superficial surgical site infection (OR=2.8; 95% CI: 1.4-5.7; P=0.004), sepsis (OR=2.2, 95% CI: 1.2-3.9; P=0.009), reoperation (OR=1.7; 95% CI: 1.2-2.5; P=0.006), pulmonary complications (OR=1.7; 95% CI: 1.1-2.5; P=0.017), and prolonged hospitalization (OR=1.4; 95% CI: 1.0-1.9; P=0.039). CONCLUSIONS: Recognition and awareness of the relationship between metabolic syndrome and postoperative complications following ASD surgery is important for preoperative optimization and perioperative care.