Stability before and after percutaneous anterior medullary fixation of lateral compression 1 and 2 pelvic ring disruptions: Should surgeons prioritize the anterior ring?

PURPOSE: Surgical intervention for lateral compression (LC) 1 and 2 pelvic ring fractures is controversial. Posterior ring stabilization remains the most common mode of initial fixation. However, greater mechanical instability is observed in the anterior component of LC pelvic fractures. This study tested whether reduction and percutaneous superior ramus fixation will decrease the instability of LC pelvic fractures on intraoperative fluoroscopic imaging. METHODS: All adult patients (≥ 18 years) presenting with either a Young-Burgess LC1 or LC2 pelvic ring disruption treated operatively with percutaneous anterior followed by posterior fixation by a single surgeon from July 2021 to June 2023 were retrospectively reviewed. Displacement of the anterior ring to intraoperative manual internal rotation stress examination under fluoroscopy was compared before and after anterior pelvic ring reduction and fixation and prior to posterior pelvic ring fixation. Pre- and post-operative visual analog scores (VAS) for pain were also compared. RESULTS: Twenty-one patients with a mean age of 48.7 years were included. Fifteen patients (71.4%) presented with an LC1, and six (28.6%) with an LC2 injury patterns. Anterior pelvic fixation alone provided 7.5mm reduction in mean displacement of the anterior pelvic ring (pre-operative = 9.2 mm vs. post-operative = 1.6 mm, p < 0.001). VAS significantly decreased from 7.2 one-day pre-operatively to 2.2 twenty-four h post-operatively (p < 0.001). CONCLUSIONS: Reduction and fixation of the anterior pelvic ring prior to posterior fixation for LC1 and LC2 pelvic ring disruptions substantially improves mechanical stability on intraoperative stress examination. Combination of percutaneous anterior and posterior fixation significantly decreased VAS above the MCID 24 h after stabilization.

Complete Blood Count Ratios Predict Adverse Events After Total Joint Arthroplasty.

INTRODUCTION: Complete blood count-based ratios (CBRs), including neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), platelet-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) are biomarkers associated with the proinflammatory surgical stress response. This study sought to determine whether preoperative CBRs are associated with postoperative complications, protracted hospital length of stay (LOS), and mortality after total joint arthroplasty, as well as establish threshold values for these outcomes for use in future investigations. METHODS: The Premier Healthcare Database was retrospectively queried for adult patients who underwent primary elective total hip arthroplasty or total knee arthroplasty (TKA). Approximate cut-point values for CBRs were identified by bootstrap simulation using the Youden index. Multivariable adjusted restricted cubic spline models using the predicted cut-point value as the threshold for odds of outcomes were created to identify a final threshold value associated with increased adjusted odds ratio (aOR) of study outcomes. RESULTS: A total of 32,868 total joint arthroplasties (THA: 12,807, TKA: 20,061) were identified. All measures predicted odds of aggregate postoperative complications (THA: NLR TV: 4.60 [aOR = 2.35], PLR TV: 163.4 [aOR = 1.32], MLR TV: 0.40 [aOR = 2.02], SII TV: 977.00 [aOR = 1.54]; TKA: NLR TV: 3.7 [aOR = 1.69], MLR TV: 0.41 [aOR = 1.62], PLR TV: 205.10 [aOR = 1.43], SII TV: 1,013.10 [aOR = 1.62]; all P < 0.05). A MLR > 0.40 [aOR = 1.54] P < 0.001) was associated with LOS ≥3 days after total hip arthroplasty while an NLR > 13.1 [aOR = 1.38] and an MLR > 0.41[aOR = 1.29] were associated with LOS ≥3 days after total knee arthroplasty (both P < 0.001). No association between inflammatory markers and inpatient mortality was observed. CONCLUSION: Given CBRs' ability to both predict outcomes and identify patients with a proinflammatory phenotype, the findings of this study provide a framework for future investigations aimed at identifying and treating high-risk patients with immune-modulating therapies. Continued work to validate these findings by applying TVs to interventional clinical trials is needed before wide clinical adoption.

Preoperative Laboratory Values Predicting Periprosthetic Joint Infection in Morbidly Obese Patients Undergoing Total Hip or Knee Arthroplasty.

BACKGROUND: Morbidly obese patients are an ever-growing high-risk population undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA) for end-stage osteoarthritis. This study sought to identify preoperative laboratory values that may serve as predictors of periprosthetic joint infection (PJI) in morbidly obese patients undergoing THA or TKA. METHODS: All morbidly obese patients with preoperative laboratory data before undergoing primary elective TKA or THA were identified using the Premier Healthcare Database. Patients who developed PJI within 90 days after surgery were compared with patients without PJI. Laboratory value thresholds were defined by clinical guidelines or primary literature. Univariate and multivariable regression analyses were utilized to assess the association between PJI and preoperative laboratory values, including total lymphocyte count, neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), albumin level, platelet count, albumin-globulin ratio, hemoglobin level, and hemoglobin A1c. RESULTS: Of the 6,780 patients identified (TKA: 76.67%; THA: 23.33%), 47 (0.69%) developed PJI within 90 days after surgery. The rate of PJI was 1.69% for patients with a hemoglobin level of <12 g/dL (for females) or <13 g/dL (for males), 2.14% for those with a platelet count of <142,000/µL or >417,000/µL, 1.11% for those with an NLR of >3.31, 1.69% for those with a PLR of >182.3, and 1.05% for those with an SII of >776.2. After accounting for potential confounding factors, we observed an association between PJI and an abnormal preoperative NLR (adjusted odds ratio [aOR]: 2.38, 95% confidence interval [CI]: 1.04 to 5.44, p = 0.039), PLR (aOR: 4.86, 95% CI: 2.15 to 10.95, p < 0.001), SII (aOR: 2.44, 95% CI: 1.09 to 5.44, p = 0.029), platelet count (aOR: 3.50, 95% CI: 1.11 to 10.99, p = 0.032), and hemoglobin level (aOR: 2.62, 95% CI: 1.06 to 6.50, p = 0.038). CONCLUSIONS: This study identified preoperative anemia, abnormal platelet count, and elevated NLR, PLR, and SII to be associated with an increased risk of PJI among patients with a body mass index of ≥40 kg/m2. These findings may help surgeons risk-stratify this high-risk patient population. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Total Hip and Total Knee Arthroplasty Outpatient Case Volume During the 2020 COVID-19 Pandemic in New York and California.

BACKGROUND: Inpatient total hip and total knee arthroplasty were substantially impacted by the SARS-CoV-2 (COVID-19) pandemic. We sought to characterize the transition of total joint arthroplasty (TJA) to the outpatient setting in 2 large state health systems during this pandemic. METHODS: Adult patients who underwent primary elective TJA between January 1, 2016 and December 31, 2020 were retrospectively reviewed using the New York Statewide Planning and Research Cooperative System and California Department of Health Care Access and Information datasets. Yearly inpatient and outpatient case volumes and patient demographics, including age, sex, race, and payer coverage, were recorded. Continuous and categorical variables were compared using descriptive statistics. Significance was set at P < .05. RESULTS: In New York during 2020, TJA volume decreased 16% because 22,742 fewer inpatient TJAs were performed. Much of this lost volume (46.6%) was offset by a 166% increase in outpatient TJA. In California during 2020, TJA volume decreased 20% because 34,114 fewer inpatient TJAs were performed. Much of this lost volume (37%) was offset by a 47% increase in outpatient TJA. CONCLUSIONS: This present study demonstrates a marked increase in the proportion of TJA being performed on an outpatient basis in both California and New York. In both states, despite a decrease in overall TJA volume in 2020, outpatient TJA volume increased markedly. LEVEL OF EVIDENCE: Therapeutic Level IV, Retrospective Cohort Study.

Dexamethasone-Associated Hyperglycemia is Not Associated With Infectious Complications After Total Joint Arthroplasty in Diabetic Patients.

BACKGROUND: Postoperative infection is a devastating complication of total joint arthroplasty (TJA). Perioperative use of dexamethasone in patients who have diabetes mellitus (DM) remains controversial due to concern for increased infection risk. This study aimed to evaluate the association between dexamethasone and infection risk among patients who have DM undergoing TJA. METHODS: This was a retrospective cohort study conducted on adult patients who underwent primary, elective total knee arthroplasty (TKA) or total hip arthroplasty (THA) between January 2016 and December 2021 using a large national database. We identified 110,568 TJA patients (TKA: 66.6%; THA: 33.4%), 31.0% (34,298) of which had DM. Patients who received perioperative dexamethasone were compared to those who did not. The primary end points were the 90-day risk of postoperative periprosthetic joint infection, surgical site infection (SSI), and other non-SSI (urinary tract infection, pneumonia, sepsis). RESULTS: When modeling the association between dexamethasone exposure and study outcomes while accounting for the interaction between dexamethasone and morning blood glucose levels, dexamethasone administration conferred no increased odds of postoperative periprosthetic joint infection nor SSI in diabetics. However, dexamethasone significantly lowered the adjusted odds of other postoperative infections in diabetic patients (TKA: adjusted odds ratio = 09, 95% confidence interval = 0.8 to 1.0, P = .030; THA: adjusted odds ratio = 0.7, 95% confidence interval = 0.6 to 0.9, P = .001); specifically in patients with morning blood glucose levels between 110 to 248 mg/dL in TKA and ≤ 172 mg/dL in THA. CONCLUSIONS: This study provides strong evidence against withholding dexamethasone in diabetic patients undergoing TJA based on concern for infection. Instead, short-course perioperative dexamethasone reduced infection risk in select patients. The narrative surrounding dexamethasone should shift away from questions about whether dexamethasone is appropriate for diabetic patients, and instead focus on how best to optimize its use.

Same-Day Total Joint Arthroplasty in the United States From 2016 to 2020: The Impact of the Medicare Inpatient Only List and the COVID-19 Pandemic.

BACKGROUND: Same-day total hip arthroplasty (THA) and total knee arthroplasty (TKA) continue to gain popularity in the United States. The present study sought to quantify recent same-day outpatient trends taking into consideration the COVID-19 pandemic as well as the removal of these procedures from the Medicare inpatient only (IPO) list. METHODS: Patients undergoing primary elective TKA and THA were identified using the Nationwide Ambulatory Surgery Sample and the National Inpatient Sample from January 1, 2016, to December 31, 2020. The same-day cohort included Nationwide Ambulatory Surgery Sample and National Inpatient Sample patients with a length of stay = 0 days. The inpatient cohort included patients with length of stay ≥1 day. National estimates were extrapolated using weight functions. RESULTS: From January 2016 to December 2020, the proportion of same-day TKA increased from 1.2 (719) to 62.4% (31,293) and the proportion of same-day THA increased from 2.0 (599) to 54.5% (18,252). Following removal from the Medicare IPO list, same-day TKAs increased from 3.2% (1,895) in December 2017 to 13.8% (9,269) in January 2018, and same-day THAs increased from 10.7% (4,295) in December 2019 to 22.5% (8,708) in January 2020. Between February and March 2020, same-day TKAs increased from 42.4 (26,148) to 44.4% (16,972) and same-day THAs increased from 28.5 (10,729) to 30.2% (7,409). CONCLUSIONS: The proportion of same-day TKA and THA dramatically increased following removal from the Medicare IPO list and in response to the COVID-19 pandemic. By December 2020, same-day TKA and THA accounted for >50% of all cases performed in the United States.

Higher Blood Glucose Levels on the Day of Surgery Are Associated with an Increased Risk of Periprosthetic Joint Infection After Total Hip Arthroplasty.

BACKGROUND: Hyperglycemia has been identified as a risk factor for periprosthetic joint infection (PJI) after total hip arthroplasty (THA). However, there is no consensus with regard to the preoperative blood glucose level (BGL) on the day of the surgical procedure associated with increased risk. We sought to identify preoperative BGL thresholds associated with an increased risk of PJI. METHODS: The Premier Healthcare Database was retrospectively queried for adult patients who underwent primary, elective THA and had a measurement of the preoperative BGL recorded on the day of the surgical procedure (preoperative BGL) from January 1, 2016, to December 31, 2021. The association between preoperative BGL and 90-day PJI risk was modeled using multivariable logistic regression with restricted cubic splines. Patients with and without diabetes with a preoperative BGL associated with 1.5 times greater odds of PJI (high preoperative BGL) were then compared with patients with a normal preoperative BGL. RESULTS: In this study, 90,830 patients who underwent THA and had a recorded preoperative BGL were identified. The preoperative BGL associated with 1.5 times greater odds of PJI was found to be 277 mg/dL in patients with diabetes and 193 mg/dL in patients without diabetes. Compared with the normal preoperative BGL cohort, those with high preoperative BGL had increased odds of PJI (adjusted odds ratio [OR], 2.60 [95% confidence interval (CI), 1.45 to 4.67] for patients with diabetes and 1.66 [95% CI, 1.10 to 2.51] for patients without diabetes) and 90-day readmissions (adjusted OR, 1.92 [95% CI, 1.45 to 2.53] for patients with diabetes and 1.66 [95% CI, 1.37 to 2.00] for patients without diabetes). CONCLUSIONS: Increased preoperative BGL was found to be associated with an increased risk of PJI following primary THA. Surgeons should be aware of patients with diabetes and a preoperative BGL of >277 mg/dL and patients without diabetes but with a preoperative BGL of >193 mg/dL. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Underweight patients experience higher inpatient complication and mortality rates following acetabular fracture.

PURPOSE: Underweight patients experience poor outcomes after elective orthopaedic procedures. The effect of underweight body mass index (BMI) on complications after acetabular fracture is not well-described. We evaluate if underweight status is associated with inpatient complications after acetabular fractures. METHODS: Adult patients (≥ 18 years) presenting with acetabular fracture between 2015 and 2019 were identified from Trauma Quality Program data. Adjusted odds (aOR) of any inpatient complication or mortality were compared between patients with underweight BMI (< 18.5 kg/m2) and normal BMI (18.5-25 kg/m2) using multivariable logistic regression and stratifying by age ≥ 65 years. RESULTS: The 1299 underweight patients aged ≥ 65 years compared to 11,629 normal weight patients experienced a 1.2-times and 2.7-times greater aOR of any complication (38.6% vs. 36.6%, p = 0.010) and inpatient mortality (7.9% vs. 4.2%, p < 0.001), respectively. The 1688 underweight patients aged 18-64 years compared to 24,762 normal weight patients experienced a 1.2-times and 1.5-times greater aOR of any inpatient complication (38.9% vs. 34.8%, aOR p = 0.006) and inpatient mortality (4.1% vs. 2.5%, p < 0.001), respectively. CONCLUSION: Underweight adult patients with acetabular fracture are at increased risk for inpatient complications and mortality, particularly those ≥ 65 years old. LEVEL OF EVIDENCE: Prognostic Level III.

Rising incidence of acute total hip arthroplasty for primary and adjunctive treatment of acetabular fracture in older and middle-aged adults.

BACKGROUND: Acute total hip arthroplasty (THA) may be an alternative or an adjuvant to internal fixation for surgical treatment of acetabular fractures. We investigate recent trends in the operative management of acetabular fractures. We hypothesize that the incidence of acute THA for acetabular fractures has increased over time. METHODS: 4569 middle-aged (45-64 years) and older adults (≥ 65 years) who received acute operative management of an acetabular fracture within 3 weeks of admission between 2010 and 2020 were identified from the United States Nationwide Inpatient Sample database. Treatment was classified as open reduction internal fixation (ORIF), THA, or combined ORIF and THA (ORIF + THA). Patients were stratified by age ≥ 65 years old. Associations between demographic factors and the incidence of each procedure over the study period were modeled using linear regression. RESULTS: The relative incidence of treatments was 80.9% ORIF, 12.1% THA, and 7.0% ORIF + THA. Among patients aged 45-64 years old, THA increased 4.8% [R2 = 0.62; ß1 = 0.6% (95% Confidence Interval (CI) 0.2-0.9%)] and ORIF + THA increased 2.6% [R2 = 0.73; ß1 = 0.3% (95% CI 0.2-0.4%)], while the use of ORIF decreased 7.4% [R2 = 0.75; ß1 = -0.9% (95% CI -1.2 to -0.5%)]. Among patients ≥ 65 years old, THA increased 16.5% [R2 = 0.87; ß1 = 1.7% (95% CI 1.2-2.2%)] and ORIF + THA increased 5.0% [R2 = 0.38, ß1 = 0.6% (95% CI 0.0-1.3%)], while ORIF decreased 21.5% [R2 = 0.75; ß1 = -2.4% (95% CI -3.45 to -1.3%)]. CONCLUSION: The treatment of acetabular fractures with acute THA has increased in the last decade, particularly among older adults.

Obesity classification predicts early complications and mortality after acetabular fracture.

INTRODUCTION: Obesity remains a global epidemic. The effect of obesity on the risk of complications after acetabular fracture is unknown. Here, we evaluate the effect of BMI on early complications and mortality after acetabular fracture. We hypothesize that the risk of inpatient complications and mortality will be greater in patients with high BMI when compared to those with normal BMI. METHODS: Adult patients with acetabular fracture were identified via the Trauma Quality Improvement Program data from 2015 to 2019. The primary outcome was overall complication rate with reference to normal-weight patients (BMI = 25-30 kg/m2). The secondary outcome was rates of death. The association of obesity class on the primary and secondary outcomes was assessed using Bonferroni-corrected multiple logistic regression models considering patient, injury, and treatment covariates. RESULTS: A total of 99,721 patients with acetabular fracture were identified. Class I obesity (BMI = 30-35 kg/m2) was associated with 1.2 greater adjusted relative risk (aRR; 95% confidence interval (CI) 1.1-1.3) of any adverse event, without significant increases in adjusted risk of death. Class II obesity (BMI = 35-40 kg/m2) was associated with aRR = 1.2 (95% CI 1.1-1.3) of any adverse event and aRR = 1.5 (95% CI 1.2-2.0) of death. Class III obesity (BMI ≥ 40 kg/m2) was associated with aRR = 1.3 (95% CI 1.2-1.4) of any adverse event and aRR = 2.3 (95% CI 1.8-2.9) of death. CONCLUSION: Obesity is associated greater risk of adverse events and death following acetabular fracture. Obesity severity classification scales with these risks.

Factors Associated With Failure Following Proximal Femoral Replacement for Salvage Hip Surgery for Nononcologic Indications.

BACKGROUND: Proximal femoral replacement (PFR) is used when extensive proximal femoral bone loss is encountered during revision total hip arthroplasty. However, further data on 5-to-10-year survivorship and predictors of failure are needed. Our aim was to assess the survivorship of contemporary PFRs used for nononcologic indications and determine factors associated with failure. METHODS: A single-institution retrospective observational study was conducted between June 1, 2010 and August 31, 2021 for patients undergoing PFR for non-neoplastic indications. Patients were followed for a minimum of 6 months. Demographic, operative, clinical, and radiographic data were collected. Implant survivorship was determined via Kaplan-Meier analysis of 56 consecutive cemented PFRs in 50 patients. RESULTS: At a mean follow-up of 4 years, the mean Oxford Hip Score was 36.2 and patient satisfaction was rated at an average of 4.7 of 5 on the Likert scale. Radiographic evidence of femoral-sided aseptic loosening was determined in 2 PFRs at a median of 9.6 years. The 5-year survivorship with all-cause reoperation and revision as end points was 83.2% (95% Confidence Interval [CI]: 70.1% to 91.0%) and 84.9% (95% CI: 72.0% to 92.2%), respectively. The 5-year survivorship was 92.3% (95% CI: 78.0% to 97.5%) for stem length > 90 mm compared to 68.4% (95% CI: 39.5% to 85.7%) for stem length ≤ 90 mm. A construct-to-stem length ratio (CSR) ≤ 1 was associated with a 91.7% (95% CI: 76.4% to 97.2%) survival, while a CSR > 1 was associated with a 73.6% (95% CI: 47.4% to 88.1%) survival. CONCLUSION: A PFR stem length ≤ 90 mm and CSR > 1 were associated with increased rates of failure.

Cirrhosis is independently associated with complications and mortality following operative treatment of acetabular fractures.

INTRODUCTION: Patients with cirrhosis are at higher risk for morbidity after injury. Acetabular fractures represent a highly morbid injury pattern. Few studies have specifically examined an effect of cirrhosis on risk of complications after acetabular fracture. We hypothesized that cirrhosis is independently associated with increased risk of inpatient complications following operative treatment of acetabular fractures. METHODS: Adults patients with acetabular fracture who underwent operative treatment were identified from Trauma Quality Improvement Program data from 2015 to 2019. Patients with and without cirrhosis were matched on a propensity score predicting cirrhotic status and inpatient complications based on patient, injury, and treatment characteristics. The primary outcome was overall complication rate. Secondary outcomes included serious adverse event rate, overall infection rate, and mortality. RESULTS: After propensity score matching, 137 cirrhosis+ and 274 cirrhosis- remained. No significant differences existed in observed characteristics after matching. Compared to cirrhosis- patients, cirrhosis+ patients experienced 43.4% (83.9 vs 40.5%, p < 0.001) greater absolute risk difference of any inpatient complication, 29.9% (51.8 vs 21.9%, p < 0.001) greater absolute risk difference of serious adverse events, 28.5% (41.6 vs 13.1%, p < 0.001) greater absolute risk difference of any infection, and 2.9% (2.9% vs 0.0%, p = 0.02) greater absolute risk difference of inpatient mortality. CONCLUSION: Cirrhosis is associated with higher rates of inpatient complications, serious adverse events, infection, and mortality among patients undergoing operative repair of acetabular fracture. LEVEL OF EVIDENCE: Prognostic Level III.

Long-Term Pulmonary Sequelae After Inhalation Injury: A Retrospective Case-Control Study.

Inhalation injury (INHI) has strong associations with increased rates of in-patient mortality and pneumonia. This study's aim is to review long-term pulmonary outcomes in INHI patients. We present a retrospective cohort of burn patients admitted to an ABA-certified burn unit. Burn patients with or without medically confirmed INHI who were admitted were studied. The control groups were ventilated patients (V) and nonventilated patients (NV). Primary study outcomes were rates of postdischarge pulmonary sequelae, including ineffective airway clearance, infections, shortness of breath, and malignancy. Secondary outcomes included rates of postdischarge surgeries and readmission, postdischarge nonpulmonary sequelae, and postdischarge days to pulmonary/nonpulmonary sequelae. The study population included 33 INHI, 45 V, and 50 NV patients. There were no significant differences in age (P = .98), sex (P = .68), % TBSA (P = .18), pulmonary comorbidity (P = .5), or smoking status (P = .92). Outpatient pulmonary sequelae were significantly higher for both INHI and V groups as compared to NV (21% and 17% vs 4%, P = .023, .043). The number of days from discharge to pulmonary sequelae was significantly shorter in the INHI group vs the V group (162 ± 139 vs 513 ± 314 days, P = .024). All other measures were not significant when comparing INHI to V or NV (P > .05). Both INHI and V groups resulted in higher rates of outpatient pulmonary sequelae independent of inpatient course as compared to NV. While outpatient pulmonary sequelae were not significantly different between INHI and V, the INHI patients presented with complaints earlier.

The Utility of Routine Postoperative Radiographs in the Asymptomatic Total Hip Arthroplasty Patient.

BACKGROUND: Total hip arthroplasty (THA) patients often receive routine radiographs in the year following their index surgery. This study sought to investigate the clinical and economic value of obtaining routine postoperative hip radiographs for asymptomatic patients following primary elective THA. METHODS: A retrospective cohort study of consecutive patients who underwent primary elective THA from 2016 to 2019 was conducted. Patients undergoing nonelective or revision THA, radiographic follow-up <10 months, and patients aged <18 years were excluded. All radiographs were reviewed for abnormalities in the first postoperative year by an arthroplasty fellowship-trained orthopaedic surgeon, blinded to the symptoms of the patient. RESULTS: Of the 327 patients (351 hips) included, 57.2% were women and 68.2% were White, with an average age of 65 years (range, 22-97 years) and average body mass index of 29.1 kg/m2 (range, 16.2-49.8 kg/m2). Only four (0.4%) radiographic series revealed abnormalities with the potential to alter postoperative management. One patient experienced a change in management directly related to their abnormal finding (closed reduction for dislocation at 10.2 months postoperatively). The remaining three abnormal radiographic findings included femoral stem subsidence, progressive radiolucencies around an acetabular component, and cement mantle fracture. The average cost for each radiographic series was $155.27, resulting in total direct charges of $167,691.60. CONCLUSION: Routine postoperative radiographs may be of limited utility in the asymptomatic patient in the first year following elective primary THA. Consideration should be given to limit postoperative radiographs following standard elective THA, while reserving postoperative radiographic evaluation for patients who are symptomatic. LEVEL OF EVIDENCE: Level III.

Preperitoneal Pelvic Packing for Hypotension Has a Greater Risk of Venous Thromboembolism Than Angioembolization: Management of Refractory Hypotension in Closed Pelvic Ring Injury.

BACKGROUND: Patients with traumatic pelvic ring injury may present with hypotension secondary to hemorrhage. Preperitoneal pelvic packing (PPP) and angioembolization (AE) are alternative interventions for management of hypotension associated with pelvic ring injury refractory to resuscitation and circumferential compression. We hypothesized that PPP may be independently associated with increased risk of venous thromboembolism (VTE) compared with AE in patients with hypotension and pelvic ring injury. METHODS: Adult patients with pelvic ring injury and hypotension managed with PPP or AE were retrospectively identified in the Trauma Quality Improvement Program (TQIP) database from 2015 to 2019. Patients were matched on a propensity score for receiving PPP based on patient, injury, and treatment factors. The primary outcome was the risk of VTE after matching on the propensity score for treatment. The secondary outcomes included inpatient clinically important deep vein thrombosis, pulmonary embolism, respiratory failure, mortality, unplanned reoperation, sepsis, surgical site infection, hospital length of stay, and intensive care unit (ICU) length of stay. RESULTS: In this study, 502 patients treated with PPP and 2,439 patients treated with AE met inclusion criteria. After propensity score matching on age, smoking status, Injury Severity Score, Tile B or C pelvic ring injury, bilateral femoral fracture, serious head injury, units of plasma and platelets given within 4 hours of admission, laparotomy, and level-I trauma center facility designation, 183 patients treated with PPP and 183 patients treated with AE remained. PPP, compared with AE, was associated with a 9.8% greater absolute risk of VTE, 6.5% greater risk of clinically important deep vein thrombosis, and 4.9% greater risk of respiratory failure after propensity score matching. CONCLUSIONS: PPP for the management of hypotension associated with pelvic ring injury is associated with higher rates of inpatient VTE events and sequelae compared with AE. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

The Effect of Hip Offset and Spinopelvic Abnormalities on the Risk of Dislocation Following Total Hip Arthroplasty.

BACKGROUND: Previous studies have demonstrated that patients with abnormal spinopelvic motion are at increased risk of dislocation. However, little is known about the effect of hip offset on dislocation risk following total hip arthroplasty (THA) in patients with abnormal spinopelvic motion. The purpose of this study is to investigate the prevalence of under-restored hip offset and spinopelvic abnormalities in a series of THA patients treated for recurrent instability. METHODS: This is a retrospective review of consecutive patients treated for hip instability following primary THA (THA+I) from 2012 to 2020. Patient demographics, surgical variables, and radiographic parameters were recorded. THA+I patients were compared to an age-matched and gender-matched control THA population without hip instability (THA). Univariate analyses were performed to compare differences between groups. RESULTS: Thirty-three THA+I patients (44 hips) were compared to 44 THA patients (44 hips). THA+I patients had a higher prevalence of spinopelvic pathology (odds ratio [OR] 7.80, 95% confidence interval [CI] 2.59-23.50, P < .001). The majority of acetabular components were placed within the Lewinnek safe zone (86.4% THA+I vs 72.7% THA; P = .119). THA+I patients were at greater risk of markedly under-restored hip offset (Δoffset ≤ 3 mm; OR 6.34, 95% CI 2.20-18.30, P = .001) and small (<32 mm) femoral head diameter (OR 4.38, 95% CI 1.53-12.53, P = .006) compared to THA patients. CONCLUSION: Lumbar degenerative disease and under-restoration of hip offset were present in a high proportion of patients with hip instability. Although multiple factors may contribute to THA instability, these data suggest that restoration of offset is essential, particularly in patients with spinopelvic pathology, and may be more important than historically described acetabular targets. LEVEL OF EVIDENCE: Level III.

A retrospective data analysis on the induction medications used in trauma rapid sequence intubations and their effects on outcomes.

PURPOSE: Rapid sequence intubation (RSI) in trauma patients is common; however, the induction agents used have been debated. We determined which induction medications were used most frequently for adult trauma RSIs and their associations with hemodynamics and outcomes. We hypothesized that etomidate is the most commonly used induction agent and has similar outcomes to other induction agents. METHODS: This retrospective review at two U.S. level I trauma centers evaluated adult trauma patients undergoing RSI within 24 h of admission, between 01/01/2016 and 12/31/2017. We compared patient characteristics and outcomes by induction agent. Comparisons on the primary outcome of in-hospital mortality and secondary outcomes of peri-intubation hypotension, hospital and ICU length of stay (LOS), ventilator days, and complications used logistic regression or negative binomial regression. Regression models adjusted for hospital site, age, patient severity measures, and intubation location. RESULTS: Among 1303 trauma patients undergoing RSI within 24 h of admission, 948 (73%) were intubated in the emergency department (ED) and 325 (25%) in the operating room (OR). The most common induction agents were etomidate (68%), propofol (17%), and ketamine (11%). In-hospital mortality was highest in the etomidate group (25.5%), followed by ketamine (17%), and propofol (1.8%). CONCLUSION: Etomidate was most commonly used in ED intubations; propofol was most used in the OR. Compared to propofol, patients induced with etomidate had higher mortality and complication rates. Findings should be interpreted with caution given limited generalizability and residual confounding by indication.

The distinct role of the four voltage sensors of the skeletal CaV1.1 channel in voltage-dependent activation.

Initiation of skeletal muscle contraction is triggered by rapid activation of RYR1 channels in response to sarcolemmal depolarization. RYR1 is intracellular and has no voltage-sensing structures, but it is coupled with the voltage-sensing apparatus of CaV1.1 channels to inherit voltage sensitivity. Using an opto-electrophysiological approach, we resolved the excitation-driven molecular events controlling both CaV1.1 and RYR1 activations, reported as fluorescence changes. We discovered that each of the four human CaV1.1 voltage-sensing domains (VSDs) exhibits unique biophysical properties: VSD-I time-dependent properties were similar to ionic current activation kinetics, suggesting a critical role of this voltage sensor in CaV1.1 activation; VSD-II, VSD-III, and VSD-IV displayed faster activation, compatible with kinetics of sarcoplasmic reticulum Ca2+ release. The prominent role of VSD-I in governing CaV1.1 activation was also confirmed using a naturally occurring, charge-neutralizing mutation in VSD-I (R174W). This mutation abolished CaV1.1 current at physiological membrane potentials by impairing VSD-I activation without affecting the other VSDs. Using a structurally relevant allosteric model of CaV activation, which accounted for both time- and voltage-dependent properties of CaV1.1, to predict VSD-pore coupling energies, we found that VSD-I contributed the most energy (~75 meV or ∼3 kT) toward the stabilization of the open states of the channel, with smaller (VSD-IV) or negligible (VSDs II and III) energetic contribution from the other voltage sensors (<25 meV or ∼1 kT). This study settles the longstanding question of how CaV1.1, a slowly activating channel, can trigger RYR1 rapid activation, and reveals a new mechanism for voltage-dependent activation in ion channels, whereby pore opening of human CaV1.1 channels is primarily driven by the activation of one voltage sensor, a mechanism distinct from that of all other voltage-gated channels.

A Fatal Case of Toxic Epidermal Necrolysis Combined With Vanishing Bile Duct Syndrome and Hemophagocytic Lymphohistiocytosis.

This case report describes a case of fatal toxic epidermal necrolysis complicated by both vanishing bile duct syndrome and hemophagocytic lymphohistiocytosis due to Influenza B infection. Here we highlight the potential for complex morbidity secondary to underlying autoimmune hypersensitivity. Furthermore, the stepwise progression of these pathologies is noted, with the initial epidermal lesions first progressing to cholestatic injury and then subsequently to the hematologic manifestations.

Network Modeling Approaches and Applications to Unravelling Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease (NAFLD) is a progressive condition of the liver encompassing a range of pathologies including steatosis, non-alcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma. Research into this disease is imperative due to its rapid growth in prevalence, economic burden, and current lack of FDA approved therapies. NAFLD involves a highly complex etiology that calls for multi-tissue multi-omics network approaches to uncover the pathogenic genes and processes, diagnostic biomarkers, and potential therapeutic strategies. In this review, we first present a basic overview of disease pathogenesis, risk factors, and remaining knowledge gaps, followed by discussions of the need and concepts of multi-tissue multi-omics approaches, various network methodologies and application examples in NAFLD research. We highlight the findings that have been uncovered thus far including novel biomarkers, genes, and biological pathways involved in different stages of NAFLD, molecular connections between NAFLD and its comorbidities, mechanisms underpinning sex differences, and druggable targets. Lastly, we outline the future directions of implementing network approaches to further improve our understanding of NAFLD in order to guide diagnosis and therapeutics.