Is Morbid Obesity a Modifiable Risk Factor in Patients Who Have Severe Knee Osteoarthritis and do Not Have a Formal Perioperative Optimization Program?

BACKGROUND: Obesity is considered a modifiable risk factor prior to total knee arthroplasty (TKA); however, little data support this hypothesis. Our purpose was to evaluate patients who have a body mass index (BMI) >40 presenting for TKA to determine the incidence of: (1) patients who achieved successful weight loss through nutritional modification or bariatric surgery and (2) patients who underwent TKA over the study period without the presence of a formal optimization program. METHODS: This was a retrospective, single-center analysis. Inclusion criteria included: Kellgren and Lawrence grade 3 or 4 knee osteoarthritis, BMI >40 at presentation, and minimum 1-year follow-up (mean 45 months) (N = 624 patients). Demographics, weight loss interventions, pursuit of TKA, maximum BMI change, and Patient-Reported Outcomes Measurement Information System scores were collected. Multivariable logistic and linear regressions evaluated associations of underlying demographic and treatment characteristics with outcomes. RESULTS: There were 11% of patients who ended up pursuing TKA over the study period. Bariatric surgery was 3.7 times more likely to decrease BMI by minimum 10 compared to nonsurgical intervention (95% confidence interval [CI] [1.7, 8.1]; P = .001). Bariatric surgery resulted in mean BMI change of -3.3 (range, 0 to 22) compared to nonsurgical interventions (-2.6 [range, 0 to 12]) and no intervention (0.4 [range, 0 to 15]; P < .0001). Bariatric surgery patients were 3.1 times more likely to undergo TKA (95% CI [1.3, 7.1]; P = .008), and nonsurgical interventions were 2.4 times more likely to undergo TKA (95% CI [1.3, 4.5]; P = .006) compared to no intervention. Non-White patients across all interventions were less likely to experience loss >5 BMI compared to White patients (95% CI [0.2, 0.9]; P = .018). CONCLUSIONS: Most patients were unable to reduce BMI more than 5 to 10 over a mean 4-year period without a formal weight optimization program. Utilization of bariatric surgery was most successful compared to nonsurgical interventions, although ultimate pursuit of TKA remained low in all cohorts.

Demographics and Early Outcomes of Commercial Antibiotic Cement Usage for Infection Prophylaxis During Primary Total Knee Arthroplasty in Patients Older Than 65 Years: An American Joint Replacement Registry Study.

INTRODUCTION: The use of antibiotic-laden bone cement (ALBC) for infection prophylaxis in the setting of primary total knee arthroplasty (TKA) remains controversial. Using data from the American Joint Replacement Registry (AJRR), (1) we examined the demographics of ALBC usage in the United States and (2) identified the effect of prophylactic commercially available ALBC on early revision and readmission for prosthetic joint infection (PJI) after primary TKA. METHODS: This is a retrospective cohort study of the AJRR from 2017 to 2020. Patients older than 65 years undergoing primary cemented TKA with or without the use of commercially available antibiotic cement were eligible for inclusion (N = 251,506 patients). Data were linked to available Medicare claims to maximize revision outcomes. Demographics including age, sex, race/ethnicity, Charlson Comorbidity Index (CCI), preoperative inflammatory arthritis, region, and body mass index (BMI) class were recorded. Cox proportional hazards regression analysis was used to evaluate the association between the two outcome measures and ALBC usage. RESULTS: Patients undergoing cemented TKA with ALBC were more likely to be Non-Hispanic Black ( P < 0.001), have a CCI of 2 or 3 ( P < 0.001), reside in the South ( P < 0.001), and had a higher mean BMI ( P < 0.001). In the regression models, ALBC usage was associated with increased risk of 90-day revision for PJI (hazards ratio 2.175 [95% confidence interval] 1.698 to 2.787) ( P < 0.001) and was not associated with 90-day all-cause readmissions. Male sex, higher CCI, and BMI >35 were all independently associated with 90-day revision for PJI. DISCUSSION: The use of commercial ALBC in patients older than 65 years for primary TKA in the AJRR was not closely associated with underlying comorbidities suggesting that hospital-level and surgeon-level factors influence its use. In addition, ALBC use did not decrease the risk of 90-day revision for PJI and was not associated with 90-day readmission rates.

Comparable performance of machine learning algorithms in predicting readmission and complications following total joint arthroplasty with external validation.

BACKGROUND: The purpose of the study was to use Machine Learning (ML) to construct a risk calculator for patients who undergo Total Joint Arthroplasty (TJA) on the basis of New York State Statewide Planning and Research Cooperative System (SPARCS) data and externally validate the calculator on a single TJA center. METHODS: Seven ML algorithms, i.e., logistic regression, adaptive boosting, gradient boosting (Xg Boost), random forest (RF) classifier, support vector machine, and single and a five-layered neural network were trained on the derivation cohort. Models were trained on 68% of data, validated on 15%, tested on 15%, and externally validated on 2% of the data from a single arthroplasty center. RESULTS: Validation of the models showed that the RF classifier performed best in terms of 30-d mortality AUROC (Area Under the Receiver Operating Characteristic) 0.78, 30-d readmission (AUROC 0.61) and 90-d composite complications (AUROC 0.73) amongst the test set. Additionally, Xg Boost was found to be the best predicting model for 90-d readmission and 90-d composite complications (AUC 0.73). External validation demonstrated that models achieved similar AUROCs to the test set although variation occurred in top model performance for 90-d composite complications and readmissions between our test and external validation set. CONCLUSION: This was the first study to investigate the use of ML to create a predictive risk calculator from state-wide data and then externally validate it with data from a single arthroplasty center. Discrimination between best performing ML models and between the test set and the external validation set are comparable. LEVEL OF EVIDENCE: III.

Utility of Diagnostic Tests Before Reimplantation in Patients Undergoing 2-Stage Revision Total Joint Arthroplasty: A Systematic Review and Meta-analysis.

INTRODUCTION: Periprosthetic joint infection (PJI) is a devastating complication after total joint arthroplasty (TJA), with treatment failure occurring in 12% to 28% after 2-stage revision. It is vital to identify diagnostic tools indicative of persistent infection or treatment failure after 2-stage revision for PJI. METHODS: The Cochrane Library, PubMed (MEDLINE), and EMBASE were searched for randomized controlled trials and comparative observational studies published before October 3, 2021, which evaluated the utility of serum/plasma biomarkers (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], interleukin-6 [IL-6], fibrinogen, D-dimer), synovial biomarkers (white blood cell [WBC] count, neutrophil percentage [PMN %], alpha-defensin [AD], leukocyte esterase [LE]), tissue frozen section, tissue culture, synovial fluid culture, or sonicated spacer fluid culture indicative of persistent infection before the second stage of 2-stage revision for PJI or treatment failure after 2-stage revision for PJI. RESULTS: A total of 47 studies including 6,605 diagnostic tests among 3,781 2-stage revisions for PJI were analyzed. Among those cases, 723 (19.1%) experienced persistent infection or treatment failure. Synovial LE (sensitivity 0.25 [0.10-0.47], specificity 0.99 [0.93-1.00], positive likelihood ratio 14.0 [1.45-135.58]) and serum IL-6 (sensitivity 0.52 [0.33-0.70], specificity 0.92 [0.85-0.96], positive likelihood ratio 7.90 [0.86-72.61]) had the highest diagnostic accuracy. However, no biomarker was associated with a clinically useful negative likelihood ratio. In subgroup analysis, synovial PMN %, synovial fluid culture, serum ESR, and serum CRP had limited utility for detecting persistent infection before reimplantation (positive likelihood ratios ranging 2.33-3.74; negative likelihood ratios ranging 0.31-0.9) and no utility for predicting failure after the second stage of 2-stage revision. CONCLUSIONS: Synovial WBC count, synovial PMN %, synovial fluid culture, serum ESR, and serum CRP have modest sensitivity and specificity for predicting persistent infection during the second stage of 2-stage revision, suggesting some combination of these diagnostic tests might be useful before reimplantation. No biomarker or culture accurately predicted treatment failure after reimplantation. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Total Joint Arthroplasty Training (Prehabilitation and Rehabilitation) in Lower Extremity Arthroplasty.

Lower extremity total joint arthroplasty (TJA) has an established track record of success and a subset of patients who fail to experience desired improvements. Current TJA success can be attributed to refined surgical techniques, improved preparation of patients for surgery, and enhanced postoperative recovery protocols. One aspect of preoperative patient preparation and enhanced postoperative recovery includes training regimens intended to prepare patients for TJA and facilitate TJA functional recovery (often referred to as using the jargon prehabilitation and rehabilitation). The importance of prehabilitation and rehabilitation is open to debate because of historically insufficient and inconsistent evidence. This review aims to provide direction for future investigative efforts by presenting an overview of current preoperative and postoperative TJA training/exercise programs within the framework of utility, timing, form, setting, and cost.

One-Electron Quantum Cyclotron as a Milli-eV Dark-Photon Detector.

We propose using trapped electrons as high-Q resonators for detecting meV dark photon dark matter. When the rest energy of the dark photon matches the energy splitting of the two lowest cyclotron levels, the first excited state of the electron cyclotron will be resonantly excited. A proof-of-principle measurement, carried out with one electron, demonstrates that the method is background free over a 7.4 day search. It sets a limit on dark photon dark matter at 148 GHz (0.6 meV) that is around 75 times better than previous constraints. Dark photon dark matter in the 0.1-1 meV mass range (20-200 GHz) could likely be detected at a similar sensitivity in an apparatus designed for dark photon detection.

Contemporary Issues in the Acquisition of Orthopaedic Surgical Skills During Residency: Competency-Based Medical Education and Simulation.

➤: Orthopaedic education should produce surgeons who are competent to function independently and can obtain and maintain board certification. ➤: Contemporary orthopaedic training programs exist within a fixed 5-year time frame, which may not be a perfect match for each trainee. ➤: Most modern orthopaedic residencies have not yet fully adopted objective, proficiency-based, surgical skill training methods despite nearly 2 decades of evidence supporting the use of this methodology. ➤: Competency-based medical education backed by surgical simulation rooted in proficiency-based progression has the potential to address surgical skill acquisition challenges in orthopaedic surgery.

Does Hypothetical Centralization of Revision THA and TKA Exacerbate Existing Geographic or Demographic Disparities in Access to Care by Increased Patient Travel Distances or Times? A Large-database Study.

BACKGROUND: Higher hospital volume is associated with lower rates of adverse outcomes after revision total joint arthroplasty (TJA). Centralizing revision TJA care to higher-volume hospitals might reduce early complication and readmission rates after revision TJA; however, the effect of centralizing revision TJA care on patient populations who are more likely to experience challenges with access to care is unknown. QUESTIONS/PURPOSES: (1) Does a hypothetical policy of transferring patients undergoing revision TJA from lower-to higher-volume hospitals increase patient travel distance and time? (2) Does a hypothetical policy of transferring patients undergoing revision TJA from lower- to higher-volume hospitals disproportionately affect travel distance or time in low income, rural, or racial/ethnic minority populations? METHODS: Using the Medicare Severity Diagnosis Related Groups 466-468, we identified 37,147 patients with inpatient stays undergoing revision TJA from 2008 to 2016 in the Statewide Planning and Research Cooperative System administrative database for New York State. Revisions with missing or out-of-state patient identifiers (3474 of 37,147) or those associated with closed or merged facilities (180 of 37,147) were excluded. We chose this database for our study because of relative advantages to other available databases: comprehensive catchment of all surgical procedures in New York State, regardless of payer; each patient can be followed across episodes of care and hospitals in New York State; and New York State has an excellent cross-section of hospital types for TJA, including rural and urban hospitals, critical access hospitals, and some of the highest-volume centers for TJA in the United States. We divided hospitals into quartiles based on the mean revision TJA volume. Overall, 80% (118 of 147) of hospitals were not for profit, 18% (26 of 147) were government owned, 78% (115 of 147) were located in urban areas, and 48% (70 of 147) had fewer than 200 beds. The mean patient age was 66 years old, 59% (19,888 of 33,493) of patients were females, 79% (26,376 of 33,493) were white, 82% (27,410 of 33,493) were elective admissions, and 56% (18,656 of 33,493) of admissions were from government insurance. Three policy scenarios were evaluated: transferring patients from the lowest 25% by volume hospitals, transferring patients in the lowest 50% by volume hospitals, and transferring patients in the lowest 75% by volume hospitals to the nearest higher-volume institution by distance. Patients who changed hospitals and travelled more than 60 miles or longer than 60 minutes with consideration for average traffic patterns after the policy was enacted were considered adversely affected. The secondary outcome of interest was the impact of the three centralization policies, as defined above, on lower-income, nonwhite, rural versus urban counties, and Hispanic ethnicity. RESULTS: Transferring patients from the lowest 25% by volume hospitals resulted in only one patient stay that was affected by an increase in travel distance and travel time. Transferring patients from the lowest 50% by volume hospitals resulted in 9% (3050 of 33,493) of patients being transferred, with only 1% (312 of 33,493) of patients affected by either an increased travel distance or travel time. Transferring patients from the lowest 75% by volume hospitals resulted in 28% (9323 of 33,493) of patients being transferred, with 2% (814 of 33,493) of patients affected by either an increased travel distance or travel time. Nonwhite patients were less likely to encounter an increased travel distance or time after being transferred from the lowest 50% by volume hospitals (odds ratio 0.31 [95% CI 0.15 to 0.65]; p = 0.002) or being transferred from the lowest 75% by volume hospitals (OR 0.10 [95% CI 0.07 to 0.15]; p < 0.001) than white patients were. Hispanic patients were more likely to experience increased travel distance or time after being transferred from the lowest 50% by volume hospitals (OR 12.3 [95% CI 5.04 to 30.2]; p < 0.001) and being transferred from the lowest 75% by volume hospitals (OR 3.24 [95% CI 2.24 to 4.68]; p < 0.001) than non-Hispanic patients were. Patients from a county with a lower median income were more likely to experience increased travel distances or time after being transferred from the lowest 50% by volume hospitals (OR 69.5 [95% CI 17.0 to 283]; p < 0.001) and being transferred from the lowest 75% by volume hospitals (OR 3.86 [95% CI 3.21 to 4.64]; p < 0.001) than patients from counties with a higher median income. Patients from rural counties were more likely to be affected after being transferred from the lowest 50% by volume hospitals (OR 98 [95% CI 49.6 to 192.2]; p < 0.001) and being transferred from the lowest 75% by volume hospitals (OR 11.7 [95% CI 9.89 to 14.0]; p < 0.001) than patients from urban counties. CONCLUSION: Although centralizing revision TJA care to higher-volume institutions in New York State did not appear to increase the travel burden for most patients, policies that centralize revision TJA care will need to be carefully designed to minimize the disproportionate impact on patient populations that already face challenges with access to healthcare. Further studies should examine the feasibility of establishing centers of excellence designations for revision TJA, the effect of best practices adoption by lower volume institutions to improve revision TJA care, and the potential role of care-extending technology such as telemedicine to improve access to care to reduce the effects of travel distances on affected patient populations. LEVEL OF EVIDENCE: Level III, prognostic study.

Antibiotic Stewardship Interventions Improve Choice of Antibiotic Prophylaxis in Total Joint Arthroplasty in Patients with Reported Penicillin Allergies.

BACKGROUND: Most patients who report a penicillin allergy can tolerate cefazolin, the preferred prophylaxis in a total joint arthroplasty (TJA). Regardless, patients with a reported penicillin allergy are less likely to receive first-line perioperative antibiotics as a result of inaccurate penicillin allergy documentation and misconceptions regarding cross-reactivity between penicillin and cephalosporins. The over-reporting of penicillin allergies and the safety of cephalosporins in patients with reported penicillin allergies have been well established throughout the evidence [13]. QUESTIONS/PURPOSES: The study sought to answer two questions: (1) Do antibiotic stewardship interventions improve adherence to appropriate prophylactic antibiotic usage in patients with a documented penicillin allergy undergoing primary TJA? (2) What is the risk of allergic or adverse reactions secondary to cefazolin use in patients with a documented penicillin allergy? METHODS: This was a single-center, retrospective study of orthopaedic patients older than 18 years who underwent a primary elective TJA at a 261-bed community hospital. The study had two periods: the preintervention period ran from March 1, 2017 to August 30, 2017 and the postintervention period was from March 1, 2019 to August 30, 2019. A total of 396 patients with a history of a documented penicillin allergy underwent a THA or TKA during the study periods. After reviewing every fourth patient with a history of a documented penicillin allergy who met study inclusion criteria and excluding those patients who had a codocumented cephalosporin allergy, a total of 180 patients with a documented penicillin allergy were evaluated (90 patients in the preintervention group and 90 patients in the postintervention group). To answer our first study question, regarding whether antibiotic stewardship interventions improve adherence to appropriate prophylactic antibiotic usage in patients with a documented penicillin allergy undergoing primary TJA, we evaluated appropriate antibiotic usage pre- and postintervention. To answer our second study question, concerning the risk of allergic or adverse reactions secondary to cefazolin use in patients with a documented penicillin allergy, we reviewed signs of allergic reactions in patients who received cefazolin for a primary TJA and had a documented penicillin allergy. RESULTS: Postintervention antibiotic use was more appropriate (91% [82 of 90] versus 54% [49 of 90], risk ratio 1.67 [95% confidence interval 1.37 to 2.04]; p < 0.01), particularly in patients with nonsevere allergy (preintervention: 47% [36 of 76] versus postintervention: 96% [76 of 79]; p < 0.01). No patients had signs of an allergic reaction related to cefazolin, including eight patients with severe penicillin allergy. CONCLUSION: A multifaceted antibiotic stewardship intervention increased the appropriateness of antibiotic prophylaxis in elective primary TJA. Patients with nonsevere penicillin allergies, even those reporting hives or local swelling, tolerated cefazolin. Antibiotic stewardship interventions can be implemented across institutions to expand cephalosporin use in patients with a reported penicillin allergy within orthopaedic TJA patients. LEVEL OF EVIDENCE: Level III, therapeutic study.

Early complications and reoperation rates are similar amongst open reduction internal fixation, intramedullary nail, and distal femoral replacement for periprosthetic distal femur fractures: a systematic review and meta-analysis.

BACKGROUND: Our purpose was to perform a systematic review and meta-analysis to evaluate complication and revision rates for periprosthetic distal femur fractures (PPDFF) treated with: (1) ORIF using periarticular locking plates (ORIF), (2) retrograde intramedullary nail (IMN), and (3) distal femoral replacement (DFR). METHODS: Systematic review of the literature was performed to identify eligible studies (N = 52). Identified treatment groups were: ORIF (N = 1205 cases), IMN (N = 272 cases), and DFR (N = 353 cases). Median follow-up was 30 months (range 6-96 months). Primary outcomes were: (1) major complication rates and (2) reoperation rates over the follow-up period. Secondary outcomes were incidence of deep infection, periprosthetic fracture, mortality over the follow-up period, 1-year mortality, non-union, malunion, delayed union, and hardware failure. Data for primary and secondary outcomes were pooled and unadjusted analysis was performed. Meta-analysis was performed on subset of individual studies comparing at least two of three treatment groups (N = 14 studies). Odds-ratios and their respective standard errors were determined for each treatment group combination. Maximum likelihood random effects meta-analysis was conducted for primary outcomes. RESULTS: From the systematic review, major complication rates (p = 0.55) and reoperation rates (p = 0.20) were not significantly different between the three treatment groups. DFR group had a higher incidence of deep infection relative to IMN and ORIF groups (p = 0.03). Malunion rates were higher in IMN versus ORIF (p = 0.02). For the meta-analysis, odds of major complications were not significantly different between IMN versus DFR (OR 1.39 [0.23-8.52]), IMN versus ORIF (OR 0.86 [0.48-1.53]), or the ORIF versus DFR (OR 0.91 [0.52-1.59]). Additionally, odds of a reoperation were not significantly different between IMN versus DFR (OR 0.59 [0.08-4.11]), IMN versus ORIF (OR 1.26 [0.66-2.40]), or ORIF versus DFR (OR 0.91 [0.51-1.55]). CONCLUSIONS: There was no difference in major complications or reoperations between the three treatment groups. Deep infection rates were higher in DFR relative to internal fixation, malunion rates were higher in IMN versus ORIF, and periprosthetic fracture rates were higher in DFR and IMN versus ORIF.

An Electronic Medical Record-Based Discharge Disposition Tool Gets Bundle Busted: Decaying Relevance of Clinical Data Accuracy in Machine Learning.

BACKGROUND: Determining discharge disposition after total joint arthroplasty (TJA) has been a challenge. Advances in machine learning (ML) have produced computer models that learn by example to generate predictions on future events. We hypothesized a trained ML algorithm's diagnostic accuracy will be better than that of current predictive tools to predict discharge disposition after primary TJA. METHODS: This study was a retrospective cohort study from a single, tertiary referral center for primary TJA. We trained and validated an artificial neural network (ANN) based on 4368 distinct surgical encounters between 1/1/2013 and 6/28/2016. The ANN's ability to identify discharge disposition was then tested on 1452 distinct surgical encounters between 1/3/17 and 11/30/17. RESULTS: The area under the curve and accuracy achieved during model validation were 0.973 and 91.7%, respectively, with 25% of patients being discharged to skilled nursing facilities (SNFs). Within our testing data set, 6.7% of patients went to SNFs. The performance in the testing set included an area under the curve of 0.804, accuracy of 61.3%, sensitivity of 28.9%, and specificity of 93.8%. CONCLUSIONS: This is the first prediction tool using an electronic medical record-integrated ANN to predict discharge disposition after TJA based on locally generated data. Dramatically reduced numbers of patients discharged to SNFs due to implementation of a bundled payment model lead to poor recall in the testing model. This model serves as a proof of concept for developing an ML prediction tool using a relatively small data set and subsequent integration into the electronic medical record.

Antibiotic Stewardship for Total Joint Arthroplasty in 2020.

Projections indicate an increase in primary and revision total joint arthroplasties (TJAs). Periprosthetic joint infections (PJIs) are one of the most common and devastating causes of failure after TJA. Perioperative administration of systemic and/or local antibiotics is used for both prophylaxis and treatment of PJI. Antibiotic stewardship is a term that has been met with clinical acceptance and success in other specialties of medicine. Identifying antibiotic best practice use in the fight against PJI is limited by studies that are extremely heterogeneous in their design. Variations in studies include antibiotic selection and duration, surgical débridement steps, type of antibiotic delivery (intra-articular, local, intravenous, and prolonged oral), mix of primary and revision surgery cohorts, both hip and knee cohorts, infecting organisms, and definitions of treatment success/failure. This review highlights the current challenges of antibiotic stewardship in TJA.

What Is the Association Between Hospital Volume and Complications After Revision Total Joint Arthroplasty: A Large-database Study.

BACKGROUND: Studies of primary total joint arthroplasty (TJA) show a correlation between hospital volume and outcomes; however, the relationship of volume to outcomes in revision TJA is not well studied. QUESTIONS/PURPOSES: We therefore asked: (1) Are 90-day readmissions more likely at low-volume hospitals relative to high-volume hospitals after revision THA and TKA? (2) Are in-hospital and 90-day complications more likely at low-volume hospitals relative to high-volume hospitals after revision THA and TKA? (3) Are 30-day mortality rates higher at low-volume hospitals relative to high-volume hospitals after revision THA and TKA? METHODS: Using 29,948 inpatient stays undergoing revision TJA from 2008 to 2014 in the Statewide Planning and Research Cooperative System (SPARCS) database for New York State, we examined the relationship of hospital revision volume by quartile and outcomes. The top 5 percentile of hospitals was included as a separate cohort. Advantages of the SPARCS database include comprehensive catchment of all cases regardless of payer, and the ability to track each patient across hospital admissions at different institutions within the state. The outcomes of interest included 90-day all-cause readmission rates and 30- and 90-day reoperation rates, postoperative complication rates, and 30-day mortality rates. The initial cohort that met the MS-DRG and ICD-9 criteria consisted of 30,354 inpatient stays for revision hip or knee replacements. Exclusions included patients with a missing patient identifier (n = 221), missing admission or discharge dates (n = 5), and stays from hospitals that were closed during the study period (n = 180). Our final analytic cohort comprised 29,948 inpatient stays for revision hip and knee replacements from 25,977 patients who had nonmissing data points for the variables of interest. Outcomes were adjusted for underlying hospital, surgeon, and patient confounding variables. The analytic cohort included observations from 25,977 patients, 138 hospitals, 929 surgeons, 14,130 revision THAs, 11,847 revision TKAs, 15,341 female patients (59% of cohort). RESULTS: Patients had lower all-cause 90-day readmission rates in the highest 5th percentile by volume hospitals relative to all other lower hospital volume categories. Reoperation rates within the first 90 days, however, were not different among volume categories. All-cause 90-day readmissions were higher in the quartile 4 hospitals excluding the top 5th percentile (17%) versus the top 5th percentile by volume hospitals (12%) (odds ratio [OR]: 1.3; 95% confidence interval [CI], 1.0-1.5; p = 0.030). All-cause 90-day readmissions were higher in the quartile 3 hospitals (18%) relative to the top 5 percentile by volume hospitals (12%) (OR: 1.5; 95% CI, 1.2-1.9; p < 0.001). All-cause 90-day readmissions were higher in quartile 2 hospitals (18%) relative to the top 5 percentile by volume hospitals (12%) (OR: 1.4; 95% CI, 1.1-1.8; p = 0.010). All-cause 90-day readmissions were higher in quartile 1 hospitals (21%) versus the top 5 percentile by volume hospitals (12%) (OR: 1.6; 95% CI, 1.1-2.3; p = 0.010). Postoperative complication rates were higher among only the quartile 1 hospitals compared with institutions in each higher-volume category after revision TJA. The odds of 90-day complications compared with quartile 1 hospitals were 0.49 (95% CI, 0.33-0.72; p = 0.010) for quartile 2, 0.60 (95% CI, 0.40-0.88; p = 0.010) for quartile 3, 0.43 (95% CI, 0.28-0.64; p = 0.010) for quartile 4 excluding top 5 percentile, and 0.36 (95% CI, 0.22-0.59; p = 0.010) for the top 5 percentile of hospitals. There does not appear to be an association between 30-day mortality rates and hospital volume in revision TJA. The odds of 30-day mortality compared with quartile 1 hospitals were 0.54 (95% CI, 0.20-1.46; p = 0.220) for quartile 2, 0.75 (95% CI, 0.30-1.91; p = 0.550) for quartile 3, 0.57 (95% CI, 0.22-1.49; p = 0.250) for quartile 4 excluding top 5 percentile, and 0.61 (95% CI, 0.20-1.81; p = 0.370) for the top 5 percentile of hospitals. CONCLUSIONS: These findings suggest that regionalizing revision TJA services, or concentrating surgical procedures in higher-volume hospitals, may reduce early complications rates and 90-day readmission rates. Disadvantages of regionalization include reduced access to care, increased patient travel distances, and possible capacity issues at receiving centers. Further studies are needed to evaluate the benefits and negative consequences of regionalizing revision TJA services to higher-volume revision TJA institutions. LEVEL OF EVIDENCE: Level III, therapeutic study.

Ankle and hindfoot fusions: comparison of outcomes in patients with and without diabetes.

BACKGROUND: Patients with diabetes mellitus (DM) are believed to have higher complication rates when undergoing ankle and hindfoot fusions, but data is lacking. The purpose of this study was to compare the postoperative outcomes of major foot and ankle arthrodeses in patients with and without DM. Another goal was to evaluate what effect glycemic control had on the outcomes of patients with diabetes. METHODS: A retrospective review of charts from operative years 2005 to 2010 was performed. Inclusion criteria encompassed patients requiring major hindfoot and/or ankle fusion. Exclusion criteria included any patient who did not have at least 6-month followup. Seventy four patients with DM were matched with 74 non-DM patients based on age, gender, and length of surgery. Significance was set at p < 0.05 with associated 95% confidence intervals. RESULTS: The overall complication rate was found to be significantly higher in patients with DM, a history of tobacco use, and peripheral neuropathy. The postoperative infection rate was found to be significantly higher in patients with DM, poor long-term glucose control (Hgb A1c levels greater than or equal to 7%), a history of tobacco use, peripheral artery disease, and peripheral neuropathy. Our rate of noninfectious complications was found to be significantly higher in patients with DM, poor short-term glucose control (a preoperative glucose greater than 200 mg/dL), a history of tobacco use, and previous solid organ transplantation. Patients greater than or equal to 65 years of age were significantly associated with fewer overall complications and postoperative infections. CONCLUSION: This study confirmed our hypothesis that patients with DM were at increased risk for postoperative complications after foot and/or ankle arthrodesis when compared to patients without DM. A secondary finding of this study demonstrated patients with poor short- and long-term glucose control experienced more complications.

Pneumocephalus after resection of a lung cancer with posterior chest wall involvement.

Pneumocephalus after resection of intrathoracic tumors is an extremely rare event. A delayed presentation of iatrogenic subarachnoid pleural fistula resulted in symptomatic pneumocephalus after resection of a locally recurrent T4N0 nonsmall cell lung cancer involving the chest wall, T2 to T4 rib heads, and intercostal vertebral foramina. Progressive neurologic decline was noted 3 weeks after discharge. Computed tomography of the head and chest confirmed the presence of an apical pleural space, thoracic subarachnoid air, and pneumocephalus. Immediate clinical improvement followed chest tube decompression of the pleural space.