Search

Purpose: Surgical correction for AIS has evolved from all hooks to hybrids or all screw constructs. Limited literature exists reporting outcomes using PHDS for posterior spinal fusion (PSF). This is the largest series in evaluating results of PHDS technique. Methods: A retrospective review of consecutive AIS patients undergoing PSF by a single surgeon between 2006 and 2015 was performed. All eligible patients met a minimum 2-year follow-up. Patient demographics and radiographical parameters (radiographic shoulder height (RSH), T1 tilt, clavicle angle) at baseline, 6-week and 2-year post-operation were recorded. The primary outcome was difference in RSH from baseline measurements evaluated using repeated measures one-way analysis of variance with Bonferroni correction. Results: A total of 219 patients (mean age at surgery: 13.68 years; 82% female) were included. The mean follow-up was 41.2 months (range 24–108 months). The RSH was significantly improved from − 14.7 ± 10.38 mm to 8.0 ± 6.9 mm (P < 0.0001). Clavicle angle was improved from 2.13° to 1.31° (P < 0.0001). T1 tilt was improved from 5.6° to 2.2° (P < 0.0001). At last follow-up, 95.8% of patients were shoulder balanced. There was a significant improvement of Cobb angle with an average correction of the upper thoracic curve of 42% and main thoracic curve of 67%. Conclusion: The PHDS demonstrates the potential for additional shoulder balance improvement. Extension of fusion to structural proximal thoracic spine is the key to success for shoulder balance. It remains to be seen whether these improvements will translate into improved clinical outcomes in the longer term. [ABSTRACT FROM AUTHOR]

Background: Use of large clinical and administrative databases for orthopaedic research has increased exponentially. Each database represents unique patient populations and varies in their methodology of data acquisition, which makes it possible that similar research questions posed to different databases might result in answers that differ in important ways.Questions/purposes: (1) What are the differences in reported demographics, comorbidities, and complications for patients undergoing primary TKA among four databases commonly used in orthopaedic research? (2) How does the difference in reported complication rates vary depending on whether only inpatient data or 30-day postoperative data are analyzed?Methods: Patients who underwent primary TKA during 2010 to 2012 were identified within the National Surgical Quality Improvement Programs (NSQIP), the Nationwide Inpatient Sample (NIS), the Medicare Standard Analytic Files (MED), and the Humana Administrative Claims database (HAC). NSQIP is a clinical registry that captures both inpatient and outpatient events up to 30 days after surgery using clinical reviewers and strict definitions for each variable. The other databases are administrative claims databases with their comorbidity and adverse event data defined by diagnosis and procedure codes used for reimbursement. NIS is limited to inpatient data only, whereas HAC and MED also have outpatient data. The number of patients undergoing primary TKA from each database was 48,248 in HAC, 783,546 in MED, 393,050 in NIS, and 43,220 in NSQIP. NSQIP definitions for comorbidities and surgical complications were matched to corresponding International Classification of Diseases, 9 Revision/Current Procedural Terminology codes and these coding algorithms were used to query NIS, MED, and HAC. Age, sex, comorbidities, and inpatient versus 30-day postoperative complications were compared across the four databases. Given the large sample sizes, statistical significance was often detected for small, clinically unimportant differences; thus, the focus of comparisons was whether the difference reached an absolute difference of twofold to signify an important clinical difference.Results: Although there was a higher proportion of males in NIS and NSQIP and patients in NIS were younger, the difference was slight and well below our predefined threshold for a clinically important difference. There was variation in the prevalence of comorbidities and rates of postoperative complications among databases. The prevalence of chronic obstructive pulmonary disease (COPD) and coagulopathy in HAC and MED was more than twice that in NIS and NSQIP (relative risk [RR] for COPD: MED versus NIS 3.1, MED versus NSQIP 4.5, HAC versus NIS 3.6, HAC versus NSQIP 5.3; RR for coagulopathy: MED versus NIS 3.9, MED versus NSQIP 3.1, HAC versus NIS 3.3, HAC versus NSQIP 2.7; p < 0.001 for all comparisons). NSQIP had more than twice the obesity as NIS (RR 0.35). Rates of stroke within 30 days of TKA had more than a twofold difference among all databases (p < 0.001). HAC had more than twice the rates of 30-day complications at all endpoints compared with NSQIP and more than twice the 30-day infections as MED. A comparison of inpatient and 30-day complications rates demonstrated more than twice the amount of wound infections and deep vein thromboses is captured when data are analyzed out to 30 days after TKA (p < 0.001 for all comparisons).Conclusions: When evaluating research utilizing large databases, one must pay particular attention to the type of database used (administrative claims, clinical registry, or other kinds of databases), time period included, definitions utilized for specific variables, and the population captured to ensure it is best suited for the specific research question. Furthermore, with the advent of bundled payments, policymakers must meticulously consider the data sources used to ensure the data analytics match historical sources.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Research is a foundational component of an orthopaedic residency. It fosters intellectual curiosity and pursuit of excellence, while teaching discipline and the scientific method. These are the key principles for careers in both community-based practice and academia. Currently, no consensus exists on how to best engage residents and support their research endeavors. In 2014, the American Academy of Orthopaedic Surgeons Board of Specialty Societies Research and Quality Committee convened a Clinician-Scientist Collaboration Workgroup. The workgroup's task was to identify barriers to clinical and basic science research, and to propose feasible recommendations to overcome these barriers. Herein, we have compiled the opinions of various stakeholder constituencies on how to foster scholarly pursuits during an orthopaedic residency. These opinions reflect the workgroup's conclusions that research is directly and indirectly influenced by funding, departmental support, and mentorship, and that early exposure and dedicated time to pursue scholarly activities may have a positive impact on lifelong research interests. [ABSTRACT FROM AUTHOR]

We test whether cost-object-level characteristics significantly and predictably affect resource use within a single standardized activity. Using data on operating time for joint replacements, we find reliable effects for age, race, and gender after controlling for body mass index and other comorbidities. Modeling such granular variation is practically not possible in a classic two-stage system. Thus, this finding provides strong support for the use of time equations, as in time-driven activity-based costing, to model resource use. Supplementary analyses of hospital length of stay and gross charges show that, in addition to the expected direct effects, hospital-level characteristics moderate how patient-level attributes affect resource use. [ABSTRACT FROM AUTHOR]

Background: Infection after total knee arthroplasty (TKA) can result in disastrous consequences. Previous research regarding injections and risk of TKA infection have produced conflicting results and in general have been limited by small cohort size.Questions/purposes: The purpose of this study was to evaluate if intraarticular injection before TKA increases the risk of postoperative infection and to identify if time between injection and TKA affect the risk of TKA infection.Methods: The Humana data set was reviewed from 2007 to 2014 for all patients who received a knee injection before TKA. Current Procedural Terminology (CPT) codes and laterality modifiers were used to identify patients who underwent knee injection followed by ipsilateral TKA. Postoperative infection within 6 months of TKA was identified using International Classification of Diseases, 9th Revision/CPT codes that represent two infectious endpoints: any postoperative surgical site infection (encompasses all severities of infection) and operative intervention for TKA infection (surrogate for deep TKA infection). The injection cohort was stratified into 12 subgroups by monthly intervals out to 12 months corresponding to the number of months that had elapsed between injection and TKA. Risk of postoperative infection was compared between the injection and no injection cohorts. In total, 29,603 TKAs (35%) had an injection in the ipsilateral knee before the TKA procedure and 54,081 TKA cases (65%) did not. The PearlDiver database does not currently support line-by-line output of patient data, and so we were unable to perform a multivariate analysis to determine whether other important factors may have varied between the study groups that might have had a differential influence on the risk of infection between those groups. However, the Charlson Comorbidity index was no different between the injection and no injection cohorts (2.9 for both) suggesting similar comorbidity profiles between the groups.Results: The proportion of TKAs developing any postoperative infection was higher among TKAs that received an injection before TKA than in those that did not (4.4% versus 3.6%; odds ratio [OR], 1.23; 95% confidence interval [CI], 1.15-1.33; p < 0.001). Likewise, the proportion of TKAs developing infection resulting in return to the operating room after TKA was also higher among TKAs that received an injection before TKA than those that did not (1.49% versus 1.04%; OR, 1.4; 95% CI, 1.3-1.63; p < 0.001). Month-by-month analysis of time between injection and TKA revealed the odds of any postoperative infection remained higher for the injection cohort out to a duration of 6 months between injection and TKA (ORs ranged 1.23 to 1.46 when 1-6 months between injection and TKA; p < 0.05 for all) as did the odds of operative intervention for TKA infection when injection occurred within 7 months of TKA (OR ranged from 1.38 to 1.88 when 1-7 months between injection and TKA; p < 0.05 for all). When the duration between injection and TKA was longer than 6 or 7 months, the ORs were no longer elevated at these endpoints, respectively.Conclusions: Injection before TKA was associated with a higher risk of postoperative infection and appears to be time-dependent with closer proximity between injection and TKA having increased odds of infection. Further research is needed to better evaluate the risk injection before TKA poses for TKA infection; a more definitive relationship could be established with a multivariate analysis to control for other known risk factors for TKA infection.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

We test whether cost-object-level characteristics significantly and predictably affect resource use within a single standardized activity. Using data on operating time for joint replacements, we find reliable effects for age, race, and gender after controlling for body mass index and other comorbidities. Modeling such granular variation is practically not possible in a classic two-stage system. Thus, this finding provides strong support for the use of time equations, as in time-driven activity-based costing, to model resource use. Supplementary analyses of hospital length of stay and gross charges show that, in addition to the expected direct effects, hospital-level characteristics moderate how patient-level attributes affect resource use. [ABSTRACT FROM AUTHOR]

Background: A patient who dies during the followup period of a study about total hip arthroplasty (THA) cannot subsequently undergo a revision. The presence of competing events (such as deaths, in a study on implant durability) violates an assumption of the commonly used Kaplan-Meier (KM) survivorship approach. In that setting, KM-based estimates of revision frequencies will be high relative to alternative approaches that account for competing events such as cumulative incidence methods. However, the degree to which this difference is clinically relevant, and the degree to which it affects different ages of patient cohorts, has been poorly characterized in orthopaedic clinical research.Questions/purposes: The purpose of this study was to compare KM with cumulative incidence survivorship estimators to evaluate the degree to which the competing event of death influences the reporting of implant survivorship at long-term followup after THA in patients both younger than and older than 50 years of age.Methods: We retrospectively reviewed 758 cemented THAs from a prospectively maintained single-surgeon registry, who were followed for a minimum of 20 years or until death. Revision rates were compared between those younger than or older than age 50 years using both KM and cumulative incidence methods. Patient survivorship was calculated using KM methods. A total of 21% (23 of 109) of the cohort who were younger than 50 years at the time of THA died during the 20-year followup period compared with 72% (467 of 649) who were older than 50 years at the time of surgery (p < 0.001).Results: In the cumulative incidence analysis, 19% of the younger than age 50 years cohort underwent a revision for aseptic causes within 20 years as compared with 5% in the older than age 50 years cohort (p < 0.001). The KM method overestimated the risk of revision (23% versus 8.3%, p < 0.001), which represents a 21% and 66% relative increase for the younger than/older than age 50 years groups, respectively.Conclusions: The KM method overestimated the risk of revision compared with the cumulative incidence method, and the difference was particularly notable in the elderly cohort. Future long-term followup studies on elderly cohorts should report results using survivorship curves that take into account the competing risk of patient death. We observed a high attrition rate as a result of patient deaths, and this emphasizes a need for future studies to enroll younger patients to ensure adequate study numbers at final followup.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

The use of large-scale national databases for observational research in orthopaedic surgery has grown substantially in the last decade, and the data sets can be categorized as either administrative claims or clinical registries. Clinical registries contain secondary data on patients with a specific diagnosis or procedure. The data are typically used for patient outcome surveillance to improve patient safety and health-care quality. Registries used in orthopaedic research exist at the regional, national, and international levels, and many were designed to specifically collect outcomes relevant to orthopaedics, such as short-term surgical complications, longer-term outcomes (implant survival or reoperations), and patient-reported outcomes. Although heterogeneous, clinical registries-in contrast to claims data-typically have a more robust list of variables, with relatively precise prospective data input, management infrastructure, and reporting systems. Some weaknesses of clinical registries include a smaller number of patients, inconstant follow-up duration, and use of sampling methods that may limit generalizability. Within the U.S., national joint registry adoption has lagged international joint registries. Given the changing health-care environment, it is likely that clinical registries will provide valuable information that has the potential to influence clinical practice improvement and health-care policy in the future. [ABSTRACT FROM AUTHOR]

The article outlines national databases and registry research in orthopaedic surgery which is the branch of surgery concerned with conditions involving the musculoskeletal system. It mentions the increase in number of application of large-scale national databases for observational research in orthopaedic surgery. It refers on Medicare which is the national social insurance program of the Centers for Medicare and Medicaid Services (CMS) that offers health care to U.S. citizens.

The use of large-scale national databases for observational research in orthopaedic surgery has grown substantially in the last decade, and the data sets can be grossly categorized as either administrative claims or clinical registries. Administrative claims data comprise the billing records associated with the delivery of health-care services. Orthopaedic researchers have used both government and private claims to describe temporal trends, geographic variation, disparities, complications, outcomes, and resource utilization associated with both musculoskeletal disease and treatment. Medicare claims comprise one of the most robust data sets used to perform orthopaedic research, with >45 million beneficiaries. The U.S. government, through the Centers for Medicare & Medicaid Services, often uses these data to drive changes in health policy. Private claims data used in orthopaedic research often comprise more heterogeneous patient demographic samples, but allow longitudinal analysis similar to that offered by Medicare claims. Discharge databases, such as the U.S. National Inpatient Sample, provide a wide national sampling of inpatient hospital stays from all payers and allow analysis of associated adverse events and resource utilization. Administrative claims data benefit from the high patient numbers obtained through a majority of hospitals. Using claims, it is possible to follow patients longitudinally throughout encounters irrespective of the location of the institution delivering health care. Some disadvantages include lack of precision of ICD-9 (International Classification of Diseases, Ninth Revision) coding schemes. Much of these data are expensive to purchase, complicated to organize, and labor-intensive to manipulate-often requiring trained specialists for analysis. Given the changing health-care environment, it is likely that databases will provide valuable information that has the potential to influence clinical practice improvement and health policy for years to come. [ABSTRACT FROM AUTHOR]

Background: Total joint arthroplasty is the most frequently performed orthopaedic procedure in the United States. The purpose of the present study was to identify differences in thirty-day morbidity and mortality following primary total hip and total knee arthroplasty according to smoking status and pack-year history of smoking. Methods: We queried the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database to identify patients who had undergone primary total hip or total knee arthroplasty between 2006 and 2012. Patients were stratified by smoking status and pack-year history of smoking. Thirty-day rates of mortality, wound complications, and total complications were compared with use of univariate and multivariate analyses. Results: We identified 78,191 patients who had undergone primary total hip or total knee arthroplasty. Of these, 81.8% (63,971) were nonsmokers, 7.9% (6158) were former smokers, and 10.3% (8062) were current smokers. Current smokers had a higher rate of wound complications (1.8%) compared with former smokers and nonsmokers (1.3% and 1.1%, respectively; p < 0.001). Former smokers had a higher rate of total complications (6.9%) compared with current smokers and nonsmokers (5.9% and 5.4%, respectively; p < 0.001). Multivariate analysis identified current smokers as being at increased risk of wound complications (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.21 to 1.78), particularly deep wound infection, while both current smokers (OR, 1.18; 95% CI, 1.06 to 1.31) and former smokers (OR, 1.20; 95% CI, 1.08 to 1.34) were at increased total complication risk. Increasing pack-year history of smoking resulted in increasing total complication risk. Conclusions: On the basis of our findings, current smokers have an increased risk of wound complications and both current and former smokers have an increased total complication risk following total hip or total knee arthroplasty. [ABSTRACT FROM AUTHOR]

Background: Knee arthroplasty has emerged as an effective treatment for end-stage gonarthrosis. Although total knee arthroplasty remains the gold standard, unicompartmental knee arthroplasty is an appropriate alternative for select patients. We sought to use a large, heterogeneous national database to identify differences in thirty-day complication rates between unicompartmental and total knee arthroplasty as well as to identify risk factors for complications.Methods: Patients in the ACS NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database who had undergone total or unicompartmental knee arthroplasty from 2005 to 2011 were identified. CPT (Current Procedural Terminology) codes were used to select cases of elective primary knee arthroplasty. Statistical models employing univariate and multivariate logistic regression identified risk factors associated with the thirty-day incidence of morbidity and mortality after total and unicompartmental knee arthroplasty. Propensity score matching addressed demographic differences between the total and unicompartmental knee arthroplasty cohorts.Results: A total of 29,333 patients were identified; 27,745 (94.6%) underwent total knee arthroplasty and 1588 (5.41%) underwent unicompartmental knee arthroplasty. Prior to matching, the total knee arthroplasty cohort was 63.7% female and had a mean BMI of 32.8 ± 7.3 kg/m(2), whereas the values for the unicompartmental cohort were 55.3% and 31.5 ± 6.5 kg/m(2) (p < 0.0001). The mean ages of these cohorts were 67.2 ± 10.1 and 64.0 ± 10.7 years, respectively (p < 0.0001). A previously developed and implemented propensity score matching algorithm was used to address the demographic differences. Following matching, the total complication rate did not differ significantly between the total and unicompartmental knee arthroplasty cohorts (5.29% compared with 4.16%, p = 0.35), whereas the rate of deep venous thrombosis (1.50% compared with 0.50%, p = 0.02) and the duration of hospital stay (3.4 compared with 2.2 days, p < 0.0001) were significantly higher in the total knee arthroplasty cohort.Conclusions: Comparison of total and unicompartmental knee arthroplasty revealed no differences in overall short-term (thirty-day) morbidity and mortality. Although this study does not address long-term subjective outcomes or implant survival, these findings should provide helpful information for surgeons counseling patients considering total and/or unicompartmental knee arthroplasty.Level Of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Knee arthroplasty has emerged as an effective treatment for end-stage gonarthrosis. Although total knee arthroplasty remains the gold standard, unicompartmental knee arthroplasty is an appropriate alternative for select patients. We sought to use a large, heterogeneous national database to identify differences in thirty-day complication rates between unicompartmental and total knee arthroplasty as well as to identify risk factors for complications. Methods: Patients in the ACS NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database who had undergone total or unicompartmental knee arthroplasty from 2005 to 2011 were identified. CPT (Current Procedural Terminology) codes were used to select cases of elective primary knee arthroplasty. Statistical models employing univariate and multivariate logistic regression identified risk factors associated with the thirty-day incidence of morbidity and mortality after total and unicompartmental knee arthroplasty. Propensity score matching addressed demographic differences between the total and unicompartmental knee arthroplasty cohorts. Results: A total of 29,333 patients were identified; 27,745 (94.6%) underwent total knee arthroplasty and 1588 (5.41%) underwent unicompartmental knee arthroplasty. Prior to matching, the total knee arthroplasty cohort was 63.7% female and had a mean BMI of 32.8 ± 7.3 kg/m2, whereas the values for the unicompartmental cohort were 55.3% and 31.5 ± 6.5 kg/m2 (p < 0.0001). The mean ages of these cohorts were 67.2 ± 10.1 and 64.0 ± 10.7 years, respectively (p < 0.0001). A previously developed and implemented propensity score matching algorithm was used to address the demographic differences. Following matching, the total complication rate did not differ significantly between the total and unicompartmental knee arthroplasty cohorts (5.29% compared with 4.16%, p = 0.35), whereas the rate of deep venous thrombosis (1.50% compared with 0.50%, p = 0.02) and the duration of hospital stay (3.4 compared with 2.2 days, p < 0.0001) were significantly higher in the total knee arthroplasty cohort. Conclusions: Comparison of total and unicompartmental knee arthroplasty revealed no differences in overall short-term (thirty-day) morbidity and mortality. Although this study does not address long-term subjective outcomes or implant survival, these findings should provide helpful information for surgeons counseling patients considering total and/or unicompartmental knee arthroplasty. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Risk factors for complication after single-level anterior cervical discectomy and fusion remain poorly defined. The purpose of this study was to identify the incidence and risk factors for complication from a large, prospectively collected database, with a separate emphasis on the safety of outpatient procedures.Methods: The American College of Surgeons National Surgical Quality Improvement Program prospectively collects thirty-day morbidity and mortality data from more than 480 hospitals around the United States. We retrospectively queried this database to identify cases of single-level elective anterior cervical discectomy and fusion. Univariate and multivariate analyses were used to identify risk factors for complication, and a propensity score model was used to create matched inpatient and outpatient cohorts.Results: Of 2914 cases identified, 597 (20.5%) received outpatient treatment and 2317 (79.5%) received inpatient treatment. The overall incidence of any systemic morbidity was 3.2%. There were five mortalities (0.2%), four in the inpatient cohort and one in the outpatient cohort. Patient age over sixty-five years, body mass index of >30 kg/m2, American Society of Anesthesiologists class of 3 or 4, current dialysis, current corticosteroid use, recent sepsis, and operative times longer than 120 minutes were each independent risk factors for complication in the multivariate analysis. After propensity score matching to control for comorbidities, there were no significant differences in complication rates between inpatients and outpatients, and outpatient treatment was not a risk factor for complication in the multivariate analysis.Conclusions: Single-level elective anterior cervical discectomy and fusion had low complication rates, with no additional risk seen with outpatient as compared with inpatient procedures. It seems reasonable to consider inpatient admission for any patient with the risk factors identified here, particularly difficult airways. This information may be useful to surgeons performing informed consents for medical optimization and for selecting patients most appropriate for outpatient treatment.Level Of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: The influence of resident involvement on short-term outcomes after orthopaedic surgery is mostly unknown.Questions/purposes: The purposes of our study were to examine the effects of resident involvement in surgical cases on short-term morbidity, mortality, operating time, hospital length of stay, and reoperation rate and to analyze these parameters by level of training.Methods: The 2005–2011 American College of Surgeons National Surgical Quality Improvement Program data set was queried using Current Procedural Terminology codes for 66,817 cases across six orthopaedic procedural domains: 28,686 primary total joint arthroplasties (TJAs), 2412 revision TJAs, 16,832 basic and 5916 advanced arthroscopies, 8221 lower extremity traumas, and 4750 spine arthrodeses (fusions). Bivariate and multivariate logistic regression and propensity scores were used to build models of risk adjustment. We compared the morbidity and mortality rates, length of operating time, hospital length of stay, and reoperation rate for cases with or without resident involvement. For cases with resident participation, we analyzed the same parameters by training level.Results: Resident participation was associated with higher morbidity in TJAs (odds ratio [OR], 1.6; range, 1.4–1.9), lower extremity trauma (OR, 1.3; range, 1.2–1.5), and fusion (OR, 1.4; range, 1.2–1.7) after adjustment. However, resident involvement was not associated with increased mortality. Operative time was greater (all p < 0.001) with resident involvement in all procedural domains. Longer hospital length of stay was associated with resident participation in lower extremity trauma (p < 0.001) and fusion cases (p = 0.003), but resident participation did not affect length of stay in other domains. Resident involvement was associated with greater 30-day reoperation rates for cases of lower extremity trauma (p = 0.041) and fusion (p < 0.001). Level of resident training did not consistently influence surgical outcomes.Conclusions: Results of our study suggest resident involvement in surgical procedures is not associated with increased short-term major morbidity and mortality after select cases in orthopaedic surgery. Findings of longer operating times and differences in minor morbidity should lead to future initiatives to provide resident surgical skills training and improve perioperative efficiency in the academic setting.Level Of Evidence: Level II, prognostic study. See the Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Spinal anesthesia has been associated with lower postoperative rates of deep-vein thrombosis, a shorter operative time, and less blood loss when compared with general anesthesia. The purpose of the present study was to identify differences in thirty-day perioperative morbidity and mortality between anesthesia choices among patients undergoing total knee arthroplasty. Methods: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was searched to identify patients who underwent primary total knee arthroplasty between 2005 and 2010. Complications that occurred within thirty days after the procedure in patients who had been managed with either general or spinal anesthesia were identified. Patient characteristics, thirty-day complication rates, and mortality were compared. Multivariate logistic regression identified predictors of thirty-daymorbidity, and stratified propensity scores were used to adjust for selection bias. Results: The database search identified 14,052 cases of primary total knee arthroplasty; 6030 (42.9%) were performed with the patient under spinal anesthesia and 8022 (57.1%) were performed with the patient under general anesthesia. The spinal anesthesia group had a lower unadjusted frequency of superficial wound infections (0.68% versus 0.92%; p = 0.0003), blood transfusions (5.02% versus 6.07%; p = 0.0086), and overall complications (10.72% versus 12.34%; p = 0.0032). The length of surgery (ninety-six versus 100 minutes; p < 0.0001) and the length of hospital stay (3.45 versus 3.77 days; p < 0.0001) were shorter in the spinal anesthesia group. After adjustment for potential confounders, the overall likelihood of complications was significantly higher in association with general anesthesia (odds ratio, 1.129; 95% confidence interval, 1.004 to 1.269). Patients with the highest number of preoperative comorbidities, as defined by propensity score-matched quintiles, demonstrated a significant difference between the groups with regard to the short-term complication rate (11.63% versus 15.28%; p = 0.0152). Age, female sex, black race, elevated creatinine, American Society of Anesthesiologists class, operative time, and anesthetic choice were all independent risk factors of short-term complication after total knee arthroplasty. Conclusions: Patients undergoing total knee arthroplasty who were managed with general anesthesia had a small but significant increase in the risk of complications as compared with patients who were managed with spinal anesthesia; the difference was greatest for patients with multiple comorbidities. Surgeons who perform knee arthroplasty may consider spinal anesthesia for patients with comorbidities. [ABSTRACT FROM AUTHOR]