Spinal fusion and total hip arthroplasty: why timing is important.

BACKGROUND: There is increasing debate among orthopaedic surgeons over the temporal relationship between lumbar spinal fusion (LSF) and total hip arthroplasty (THA) for patients with hip-spine syndrome. Few large studies have directly compared the results of patients who undergo LSF prior to THA (LSF-THA) to those who undergo LSF after THA (THA-LSF). The current study matched THA patients with a prior LSF to patients who underwent LSF after THA to assess: 90-day and 1-year (1) medical/surgical complications; and (2) revisions. METHODS: We queried a national, all-payer database to identify all patients undergoing THA between 2010 and 2018 (n = 716,084). The LSF-THA patients and THA-LSF patients were then matched 1:1 on age, sex, Charleson Comorbidity Index, and obesity. Medical/surgical complications and revisions at 90 days and 1 year were recorded. Categorical and continuous variables were analysed utilising t-tests and chi-square, respectively. RESULTS: LSF-THA patients experienced significantly more postoperative dislocations at 90 days and 1 year compared to THA-LSF patients (p = 0.048 and p < 0.001). There were a similar number of revisions performed for LSF-THA and THA-LSF patients at both 90 days and 1 year (p = 0.183 and p = 0.426). Furthermore, at 1 year, LSF-THA patients experienced more pneumonia (p = 0.005) and joint infection (p = 0.020). CONCLUSIONS: Prior LSF has been demonstrated to increase the risk of postoperative dislocation in patients undergoing THA. The results of the present study demonstrate increased dislocations with LSF-THA compared to THA-LSF. For "hip spine syndrome" patients requiring both LSF and THA, it may be more beneficial to undergo THA prior to LSF. Arthroplasty surgeons may wish to collaborate with spinal surgeons to ensure optimal outcomes for this group of patients.

C. Difficile Infection within 6 Months before TKA Is Associated with Increased Short-Term Complications.

A history of Clostridium difficile infection (CDI) before total knee arthroplasty (TKA) may be a marker for poor patient health and could be used to identify patients with higher risks for complications after TKA. We compared the frequency of 90-day postoperative CDI, complications, readmissions, and associated risk factors in (1) patients experiencing CDIs more than 6 months before TKA, (2) patients experiencing CDIs in the 6 months before TKA, and (3) patients without a history of CDI. We identified patients who underwent primary TKAs from 2010 to 2019 and had a history of CDI before TKA (n = 7,195) using a national, all-payer database. Patients were stratified into two groups: those with CDIs > 6 months before TKA (n = 6,027) and those experiencing CDIs ≤ 6 months before TKA (n = 1,168). These patients were compared with the remaining 1.4 million patients without a history of CDI before TKA. Chi-square and unadjusted odds ratios (ORs) with 95% confidence intervals (CI) were used to compare complication frequencies. Prior CDI during either timespan was associated with higher unadjusted odds for postoperative CDI (CDI > 6 months before TKA: OR 8.03 [95% CI 6.68-9.63]; p < 0.001; CDI ≤ 6 months before TKA: OR 59.05 [95% CI 49.66-70.21]; p < 0.001). Patients with a history of CDI before TKA were associated with higher unadjusted odds for 90-day complications and readmission compared with patients without a history of CDI before TKA. Other comorbidities and health metrics were not found to be associated with postoperative CDI (i.e., age, obesity, smoking, antibiotic use, etc.). CONCLUSION: CDI before TKA was associated with higher odds of postoperative CDI compared with patients without a history of CDI. CDI ≤ 6 months before TKA was associated with the highest odds for postoperative complications and readmissions. Providers should consider delaying TKA after CDI, if possible, to allow for patient recovery and eradication of infection.

Inflammatory bowel disease is associated with increased complications after total knee arthroplasty.

BACKGROUND: Few studies investigate the influence of inflammatory bowel disease (IBD) on complications following total knee arthroplasty (TKA). Therefore, we compared complications and readmissions frequencies after TKA in patients with Crohn's disease (CD) and ulcerative colitis (UC) to patients without IBD. METHODS: A large administrative claims database was used to identify patients who underwent primary TKAs from 2010 to 2019 and had a diagnosis of IBD before TKA. Patients were stratified into two groups: those with CD (n = 8,369) and those with UC (n = 11,347). These patients were compared a control of 1.3 million patients without an IBD diagnosis. Chi-square and unadjusted odds ratios (OR) with 95% confidence intervals (CI) were used to compare complication frequencies. Multivariable logistic regression was used to evaluate independent risk factors for 90-day complications. RESULTS: Compared to patients without IBD, patients with IBD were associated with higher unadjusted 90-day odds for Clostridium difficile infection (CDI) (CD: OR 2.81 [95% CI 2.17 to 3.63]; p < 0.001; UC: OR 3.01 [95% CI 2.43 to 3.72]; p < 0.001) and two-year periprosthetic joint infection (CD: OR 1.34 [95% CI 1.18 to 1.52]; p < 0.001; UC: OR 1.26 [95% CI 1.13 to 1.41]; p < 0.001). After controlling for risk factors like obesity, tobacco use, and diabetes, both types of IBD were associated with higher 90-day odds for CDI and PJI (p < 0.001 for all). CONCLUSION: IBD is associated with higher 90-day postoperative CDI and PJI compared with patients without IBD. Providers should consider discussing these risks with patients who have a diagnosis of IBD.

Primary total hip arthroplasty complications and costs in liver transplant recipients: a matched analysis using a national database.

BACKGROUND: The number of liver transplant recipients (LTR) is worldwide increasing and, as the survival is improving as well, there is an increasing number of patients needing total hip arthroplasty (THA). There might be increased risks for this specific group of patients and due to their comorbidities costs might be higher too. Using a big national database outcome and cost of THA should be compared between liver transplant recipients and the general population. METHODS: The study was performed using a collection of Medicare, Medicaid, and private insurance claims. Length of stay (LOS), 30-day readmissions, complications rates up to 5 years, and 90-day total cost of care between liver transplant recipients and matched non-transplant patients should be compared. All primary THAs from 2010 to 2019 were identified. 513 patients with a liver transplant before their THA were matched to 10,759 patients without a history of solid organ transplant at a 1:20 ratio based on age, sex, Charlson Comorbidity Index, obesity, and diabetes status. RESULTS: LTR had a longer average LOS (4.2 vs. 3.4 days, p < 0.001). There was no difference in the thirty-day readmissions (5.7% vs. 4.1%, p = 0.117) and 90-day dislocation rates (2.9% vs. 2.4%, p = 0.600). Total costs in the first ninety days after THA were not different between the LTR and controls (p = 0.756). CONCLUSIONS: These findings suggest that complications and costs are no major point of concern in patients with liver transplant that are operated with THA.

Preoperative Statin Exposure Reduces Periprosthetic Fractures and Revisions following Total Knee Arthroplasty.

The purpose of this study is to examine patients undergoing primary total knee arthroplasty (TKA) with and without prior history of statin use. We specifically evaluated (1) 90-day to 2-year periprosthetic fractures, (2) revisions, and (3) respective risk factors. We queried a national, all-payer database for patients undergoing primary TKA between 2010 and 2020. Chronic statin exposure was then identified and defined as more than three prescriptions filled within 1 year prior to TKA (statin users). A control cohort of patients undergoing TKA without the prior history of statin use was then created (statin naïve). Cohorts were matched 1:1 based on age range, Charlson Comorbidity Index, sex, diabetes, obesity, and tobacco use, yielding 579,136 patients. Multivariate logistic regression was performed to evaluate the risk factors for periprosthetic fractures and revisions, adjusted for demographics and comorbidities. Statin users had a lower incidence of periprosthetic fractures from 90 days to 2 years compared with the statin naïve (p < 0.001). Similarly, statin users had a lower incidence of revisions at 90 days to 2 years (p < 0.001). Using the statin-naïve cohort as a reference, statin use was independently associated with decreased odds of periprosthetic fractures and revisions. Statin use was associated with a reduced risk of periprosthetic fractures and revisions. These results may mitigate postoperative risks though statin therapy is currently not recommended for fracture-related benefits alone.

Intra-articular Hip Injections Prior to Total Hip Arthroplasty: Infection and Cost-Related Associations.

Intra-articular injections prior to total hip arthroplasty (THA) have been associated with postoperative infections. The purpose of this study was to determine whether a temporal relationship exists between hip injections prior to THA and infection. Specifically, we asked (1) Do patients who receive hip injections within 3 months of THA have a higher incidence of prosthetic joint infections (PJIs) or surgical site infections (SSIs)? and (2) Do these patients incur higher 90-day costs? Patients with hip injections prior to THA were identified using a national database from 2010 to 2019. Three laterality-specific groups (injection 0 to 3 months, 3 to 6 months, and 6 to 12 months prior to THA)were compared with a matched cohort without prior injection (n=277,841). Primary outcomes included PJIs, SSIs, and costs. Patients who had injections within 3 months of THA had a higher incidence of PJIs at 90 days (5.1% vs 1.6%, P<.01) and 1 year (6.8% vs 2.1%, P<.01), when compared with the matched cohort. They also had a higher incidence of SSIs at 90 days (2.8% vs 1.2%, P<.01) and 1 year (3.7% vs 1.7%, P<.01). Mean costs were 13.7% higher in this injection cohort. Patients who had injections between 3 and 6 months prior to THA had higher incidence and odds of postoperative PJIs at 90 days (2.6% vs 1.6%, P<.04), whereas those with injections beyond 6 months had no differences in PJIs (P≥.46). Patients who receive hip injections within 3 months of undergoing primary THA are at increased risk for postoperative PJIs, SSIs, and higher costs. This study reaffirms guidelines for when to perform THAs in these populations. [Orthopedics. 2023;46(1):19-26.].

Operative Versus Nonoperative Treatment for Closed Displaced Midshaft Clavicle Fractures.

BACKGROUND: Nonoperative treatment for clavicle fractures has historically been standard of care, but with a concomitant rise in recent operative fixation for displaced midshaft clavicle fractures (MCF), a re-evaluation of treatment modalities is necessary. The purpose of this study was to compare nonunion rates among operative and nonoperative treatment of closed displaced MCF. Specifically, we assessed the following between operative and nonoperative management: (1) 90-day to 1-year nonunion and malunion incidence; (2) 90-day medical complications; and (3) 90-day to 1-year total costs of care. METHODS: An all-payer national database was retrospectively reviewed for closed displaced MCF from 2010 to 2020 (n = 173 188). Of these, patients undergoing operative fixation within 30 days of a displaced MCF were identified (n = 17 452). Nonoperative displaced MCF patients were matched with operative patients at a 3:1 ratio. Outcomes at 90 days and 1 year included: nonunion, total cost, and complications. RESULTS: Closed displaced MCF with operative fixation resulted in significantly increased nonunion rates at 1 year compared with nonoperative treatment (3.97% vs 1.63%, odds ratio = 2.50 [2.26-2.77], P < .001). Kaplan-Meier survivorship and log-rank score demonstrated the same for a 1-year nonunion endpoint (P < .001). As expected, the operative cohort incurred higher median total costs of care at 90 days ($3255.00 vs $1024.00, P < .001) and 1 year ($1978.00 vs $4799.50, P < .001) compared with nonoperative treatment. CONCLUSION: Our study found higher nonunion incidence after operative fixation of displaced MCF. These results may serve as a catalyst for future high-quality prospective studies comparing treatment options for closed displaced MCF.

Phenotypic Frailty Score Predicts Perioperative Outcomes for Geriatric Total Joint Arthroplasty.

Various assessment tools are often used to predict perioperative morbidity among patients older than 75 years who undergo total joint arthroplasty. Yet, few studies describe the use of phenotypic frailty as a predictor for outcomes. The goal of this study was to assess phenotypic frailty with the Sinai Abbreviated Geriatric Evaluation (SAGE) and compare its utility with established assessment tools used in practice. We specifically asked: (1) Can SAGE predict 30-day outcomes, including postoperative delirium? (2) Can SAGE determine the risk of prolonged hospital length of stay? (3) Is SAGE predictive for 30-day readmissions? (4) Can SAGE determine the risk of discharge to a specialized facility? Patients undergoing total hip arthroplasty and total knee arthroplasty were evaluated with the American Association of Anesthesiologists Physical Status (ASA), Charlson Comorbidity Index (CCI), 5-point Modified Frailty Score (5-FS), and SAGE. Assessment scores were determined for each patient, and every incremental change in score was used to predict the likelihood of perioperative complications. A receiver operating characteristic analysis was also performed to calculate testing sensitivity for each assessment tool. The SAGE scores were more likely to predict 30-day complications (odds ratio [95 CI], 2.21 [1.32-3.70]), postoperative delirium (6.40 [1.78-23.03]), and length of stay greater than 2 days (3.90 [1.00-15.7]) compared with ASA, CCI, and 5-FS values. The SAGE scores were not predictive of readmission (1.77 [0.66-4.72]) or discharge to a specialized facility (1.48 [0.80-2.75]). The SAGE score was a more sensitive predictor (area under the curve, 0.700) for perioperative morbidity compared with ASA (0.638), CCI (0.662), and 5-FS (0.644) values. Therefore, SAGE scores can reliably assess risk of perioperative morbidity and may have better clinical utility than ASA, CCI, and 5-FS values for patients undergoing total joint arthroplasty. [Orthopedics. 2022;45(6):e315-e320.].

Has modern human immunodeficiency virus therapy decreased complications following total knee arthroplasty?

BACKGROUND: Anti-retroviral therapy (ART) remains the cornerstone of decreasing morbidity and mortality in human immunodeficiency virus (HIV) patients. However, a large study comparing HIV patients taking ART prior to total knee arthroplasty (TKA) is lacking. We sought to examine: (1) readmissions; (2) post-operative complications; and (3) revisions in ART-treated or untreated HIV patients compared with a non-HIV population. METHODS: We queried a national, all-payer database to identify TKA patients from 2010-2020 (n = 1,393,357). The presence or absence of ART was identified and matched with non-HIV patients based on age, sex, diabetes, obesity, and tobacco status resulting in 889 patients in each cohort. Readmissions, post-operative complications, and revisions were assessed. RESULTS: Readmissions were higher among all HIV patients and even higher in those not taking ART, as compared to the matching cohort (4.8 versus 1.6%, p < 0.01). Prosthetic joint infections (PJIs) at 1-year were higher among HIV patients who were either taking ART (4.0%; OR, 1.41 [0.82-2.45]) or not taking ART (5.1%; OR, 2.44 [1.42-4.21]) as compared to non-HIV patients (2.1%, all p < 0.03). Revision rates at 1-year trended higher in HIV patients who were taking ART (2.6%; Odds Ratio (OR), 1.94 [0.96-3.93]) and who did not take ART (3.1%; OR, 2.38 [1.20-4.70]), compared to non-HIV patients (1.3%, all p < 0.09). CONCLUSIONS: ART-treated HIV patients are associated with lower readmissions, post-operative complications, and revisions when compared to HIV patients not taking ART. The findings of this study underscore the utility of ART and patient optimization to reduce risk in HIV patients.

Social Determinants of Health in Total Hip Arthroplasty: Are They Associated With Costs, Lengths of Stay, and Patient Reported Outcomes?

BACKGROUND: Social determinants of health (SDOH) may play a larger role in predicting patient outcomes as outpatient total hip arthroplasty (THA) expands. We specifically examined the association between SDOH and patient metrics (demographics and comorbidities) for: (1) 30-day post-discharge costs of care; (2) lengths of stay (LOS); and (3) patient-reported outcomes (Hip Disability and Osteoarthritis Outcomes Score for Joints Replacement (HOOS JR)). METHODS: Medicare patients who underwent primary THA between 2018 and 2019 were identified. Those who had complete social determinant data were included (n = 136). Data elements were drawn from institutional, regional, and government databases, as well as the Social Vulnerability Index (SVI). Multiple regression analyses were performed to determine SDOH and baseline comorbidities associations with costs, LOS, and HOOS JR scores. RESULTS: Various SDOH factors were associated with higher 30-day costs, including residing in a food desert ($53,695 ± 15,485; P < .001) and the following SVI themes: 'Minority Status and Language' ($24,075 ± 9845; P = .01) and 'Housing and Transportation' ($16,190 ± 8501; P = .06), although the latter did not meet statistical significance. Baseline depression was associated with longer LOS (P = .02), while none of the other SDOH or patient metrics affected LOS. No relationships were observed between SDOH and HOOS JR changes from baseline. CONCLUSION: Patients who live in food deserts and have minority status had higher costs of care after primary THA. Poor housing and transportation may also increase costs, albeit insignificantly. These results highlight the utility of assessing SDOH-related risk factors to optimize post-operative outcomes, with potential implications for bundled care.

Low Wear at 10-Year Follow-Up of a Second-Generation Highly Cross-Linked Polyethylene in Total Hip Arthroplasty.

BACKGROUND: Characterizations and factors influencing longer term performance of second-generation sequentially irradiated and annealed highly cross-linked polyethylene (HXLPE) are lacking. We evaluated patients who underwent total hip arthroplasty with HXLPE at mean 10-year follow-up for (1) linear and volumetric wear rates, (2) patient and implant characteristics, (3) implant survivorships, and (4) functional scores. METHODS: We evaluated 130 hips (110 patients) that received HXLPE acetabular liners at a single center. The mean age was 56 years (range, 20-79 years), with a mean follow-up of 10 years (range, 8-15). Radiographic linear (millimeters/year) and volumetric (cubic millimeters/year) wear rates were quantified using radiographic analysis. Survivorship was assessed by all-cause and wear-related revision rates. Functional outcomes were assessed by Short Form 12 and modified Harris Hip Scores. RESULTS: The mean linear wear rate was 0.02 ± 0.03 mm/y, and the mean volumetric wear rate was 12.6 ± 5.3 mm3/y. Younger age had higher volumetric wear (total and yearly, P = .01). Increasing body mass index trended toward higher total and yearly linear (both, P ≤ .09) and volumetric wear (both, P ≤ .07). Ten patients required revisions, with an all-cause survivorship of 92% and a wear survivorship of 100%. The mean modified Harris Hip Scores was 84, and the mean Short Form 12 scores were 46 (physical) and 55 (mental). CONCLUSION: We observed low linear and volumetric wear rates for HXLPE at 10-year mean follow-up. Younger age and higher body mass index at the time of surgery may be important patient characteristics influencing long-term wear. These results illustrate the potential for this second-generation HXLPE to be an appropriate long-term total hip arthroplasty interface.

Sequentially Irradiated and Annealed Highly Cross-Linked Polyethylene: Linear Vector and Volumetric Wear in Total Hip Arthroplasty at 10 Years.

BACKGROUND: There is a paucity of data on the long-term performance of highly cross-linked polyethylene (HXLPE). Therefore, this study evaluated 10-year 1) functional, 2) radiographic, and 3) surgical outcomes in patients who underwent total hip arthroplasty with sequentially irradiated and annealed HXLPE. METHODS: A retrospective, multicenter study was conducted on patients who underwent primary total hip arthroplasty and received HXLPE polymer (n = 151). Two-dimensional radiographic linear and volumetric wear analyses were quantified using the Martell Hip Analysis software, while functional outcomes were assessed by analyzing postoperative Short-Form-12 (SF-12) Physical and Mental Health Surveys and Harris Hip Scores. Radiographic outcomes included yearly linear (mm/y) and volumetric (mm3/y) wear rates. Surgical outcomes included additional operations and survivorship. RESULTS: SF-12 scores were within 1 standard deviation (SD) of the normal population (SF-12 Physical: 47.0; SF-12 Mental: 52.0), while the Harris Hip Scores of 89.5 was borderline between "good" and "excellent." Total and annual linear wear rates were 0.164 mm (SD: 0.199 mm) and 0.015 mm/y (SD: 0.018 mm/y), respectively. The mean total volumetric wear rate was 141.4 mm3 (SD: 165.0) and 12.6 mm3/y (SD: 14.9 mm3/y) when broken down into a yearly rate. Eleven patients required revisions, resulting in an all-cause polyethylene survivorship of 92.7%, with a polyethylene wear survivorship of 100.0%. CONCLUSIONS: Our results demonstrate clinically undetectable linear and volumetric wear rates after 10 years in those who received the unique sequentially irradiated and annealed HXLPE. Furthermore, high rates of survivorship coupled with low all-cause revision rates illustrate the polymers' capability to potentially increase implant longevity.

Comparing Primary Total Hip Arthroplasty in Renal Transplant Recipients to Patients on Dialysis for End-Stage Renal Disease: A Nationally Matched Analysis.

BACKGROUND: Renal transplants are the most commonly performed solid-organ transplants worldwide. It is unclear whether a kidney transplant is associated with reduced postoperative complications in comparison with patients on dialysis for end-stage renal disease (ESRD). The purpose of this study was to utilize a national database to compare readmissions, complications, and costs associated with primary total hip arthroplasty (THA) between matched renal transplant recipients (RTRs) and patients on dialysis for ESRD. METHODS: Patients with a renal transplant (N = 1,401) and those on dialysis for ESRD (without a transplant) (N = 1,463) prior to being treated with a THA from 2010 to 2019 were identified within the PearlDiver database. RTRs and patients on renal dialysis were frequency-matched 1:1 on the basis of 9 patient characteristics, resulting in 582 patients in each group. Length of hospital stay, readmissions, complication rates up to 2 years, and total costs up to 1 year were compared between the groups using chi-square and multivariable logistic regression analyses to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Patients on renal dialysis had an increased mean length of stay (6.3 days) compared with RTRs (4.6 days, p < 0.01). After adjusting for age, tobacco use, and diabetes, patients on renal dialysis were more likely to be readmitted by 90 days (OR = 1.59; CI = 1.11 to 2.29, p < 0.01) and have mechanical complications (OR = 2.13; CI = 1.08 to 4.45, p = 0.03) and revisions (OR = 2.14; CI = 1.14 to 4.01, p = 0.01) by 2 years. Patients on renal dialysis were also more likely to have periprosthetic joint infections at 1 year (OR = 1.91; CI = 1.02 to 3.71, p = 0.04). Patients on dialysis incurred 14% higher costs at 1 year (p = 0.11). CONCLUSIONS: Patients on renal dialysis had more readmissions, complications, and costs after THA when compared with RTRs. Specifically, patients on renal dialysis were more likely to have longer index lengths of stay, more readmissions by 90 days, and more mechanical complications and revision surgery by 2 years. Patients on dialysis also incurred higher costs and had greater odds of PJI. These results suggest that joint surgeons may consider delaying THA in suitable patients until after renal transplantation to reduce postoperative complications and costs. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

THAs Performed Within 6 Months of Clostridioides difficile Infection Are Associated with Increased Risk of 90-Day Complications.

BACKGROUND: Clostridioides difficile infection (CDI) may be a surrogate for poor patient health. As such, a history of CDI before THA may be used to identify patients at higher risk for postoperative CDI and complications after THA. Investigations into the associations between CDI before THA and postoperative CDI and complications are lacking. QUESTIONS/PURPOSES: We compared the (1) frequency and potential risk factors for CDI after THA, (2) the frequency of 90-day complications after THA in patients with and without a history of CDI, and (3) the length of stay and frequency of readmissions in patients experiencing CDIs more than 6 months before THA, patients experiencing CDIs in the 6 months before THA, and patients without a history of CDI. METHODS: Patients undergoing primary THA from 2010 to 2019 were identified in the PearlDiver database using ICD and Current Procedural Terminology codes (n = 714,185). This analysis included Medicare, Medicaid, and private insurance claims across the United States with the ability to perform longitudinal and costs analysis using large patient samples to improve generalizability and reduce error rates. Patients with a history of CDI before THA (n = 5196) were stratified into two groups: those with CDIs that occurred more than 6 months before THA (n = 4003, median 2.2 years [interquartile range 1.2 to 3.6]) and those experiencing CDIs within the 6 months before THA (n = 1193). These patients were compared with the remaining 708,989 patients without a history of CDI before THA. Multivariable logistic regression was used to evaluate the association of risk factors and incidence of 90-day postoperative CDI in patients with a history of CDI. Variables such as antibiotic use, proton pump inhibitor use, chemotherapy, and inflammatory bowel disease were included in the models. Chi-square and unadjusted odds ratios with 95% confidence intervals were used to compare complication frequencies. A Bonferroni correction adjusted the p value significance threshold to < 0.003. RESULTS: Prior CDI during either timespan was associated with higher unadjusted odds for postoperative CDI (CDI > 6 months before THA: OR 8.44 [95% CI 6.95 to 10.14]; p < 0.001; CDI ≤ 6 months before THA: OR 49.92 [95% CI 42.26 to 58.54]; p < 0.001). None of the risk factors included in the regression were associated with increased odds for postoperative CDI in patients with preoperative history of CDI. Patients with a history of CDI before THA were associated with higher unadjusted odds for every 90-day complication compared with patients without a history of CDI before THA. CDI during either timespan was associated with longer lengths of stay (no CDI before THA: 3.8 days; CDI > 6 months before THA: 4.5 days; CDI ≤ 6 months before THA: 5.3 days; p < 0.001) and 90-day readmissions (CDI > 6 months before THA: OR 2.21 [95% CI 1.98 to 2.47]; p < 0.001; CDI ≤ 6 months before THA: OR 3.39 [95% CI 2.85 to 4.02]; p < 0.001). CONCLUSION: Having CDI before THA was associated with higher odds of postoperative CDI compared with patients without a history of CDI. A history of CDI within the 6 months before THA was associated with the greatest odds for postoperative complications and readmissions. Providers should strongly consider delaying THA until 6 months after CDI, if possible, to provide adequate time for patient recovery and eradication of infection. LEVEL OF EVIDENCE: Level III, therapeutic study.

The Effect of Modern Antiretroviral Therapy on Complication Rates After Total Hip Arthroplasty.

BACKGROUND: Antiretroviral therapy (ART) remains the cornerstone of decreasing morbidity and mortality in patients with human immunodeficiency virus (HIV), but additional information on its impact on total hip arthroplasty (THA) complication rates is needed to mitigate risks postoperatively. Therefore, we sought to examine patients with HIV who were and were not taking ART compared with a cohort without HIV in the setting of primary THA with respect to the following outcomes: length of stay, readmissions, and postoperative infection. METHODS: A retrospective database review was performed with PearlDiver for patients who underwent THA from 2010 to 2019 (n = 729,101). Patients with HIV who were and were not taking ART were then identified and were matched with patients without HIV at a 1:1:1 ratio based on age, sex, Charlson Comorbidity Index, diabetes, obesity, and tobacco use, resulting in 601 patients in each cohort. Length of stay, 30-day readmissions, and complications at 90 days and 1 year were analyzed. Continuous outcomes were measured via Student t tests, and categorical outcomes were measured via chi-square analyses. RESULTS: Patients with HIV who were and were not taking ART were found to have similar lengths of stay compared with patients without HIV (range, 4.1 to 4.3 days). Readmission rates were slightly higher in patients with HIV who were taking ART at 4.2% (odds ratio [OR], 1.96 [95% confidence interval (CI), 0.99 to 3.87]) and patients with HIV who were not taking ART at 3.5% (OR, 1.63 [95% CI, 0.81 to 3.30]) compared with patients without HIV at 2.1%. Periprosthetic joint infection rates at 1 year were slightly higher among patients with HIV who were not taking ART at 5.3% (OR, 1.41 [95% CI, 0.82 to 2.45]) compared with patients with HIV who were taking ART at 4.2% (OR, 1.09 [95% CI, 0.61 to 1.94]) and patients without HIV at 3.8%. CONCLUSIONS: Patients with HIV who are and are not taking ART are approaching normalization to the general population in the setting of THA. It is important to note that, although complications may have been mitigated by modern therapy, extreme care should be taken while clinically evaluating these patients prior to the surgical procedure given the complexity of their clinical status. The findings of this study underscore the utility of ART and patient optimization to reduce risk in this patient population. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Drosophila foraging gene plays a vital role at the start of metamorphosis for subsequent adult emergence.

The foraging (for) gene has been extensively studied in many species for its functions in development, physiology, and behavior. It is common for genes that influence behavior and development to be essential genes, and for has been found to be an essential gene in both fruit flies and mammals, with for mutants dying before reaching the adult stage. However, the biological process underlying the lethality associated with this gene is not known. Here, we show that in Drosophila melanogaster, some but not all gene products of for are essential for survival. Specifically, we show that promoter 3 of for, but not promoters 1, 2, and 4 are required for survival past pupal stage. We use full and partial genetic deletions of for, and temperature-restricted knock-down of the gene to further investigate the stage of lethality. While deletion analysis shows that flies lacking for die at the end of pupal development, as pharate adults, temperature-restricted knock-down shows that for is only required at the start of pupal development, for normal adult emergence (AE) and viability. We further show that the inability of these mutants to emerge from their pupal cases is linked to deficiencies in emergence behaviors, caused by a possible energy deficiency, and finally, that the lethality of for mutants seems to be linked to protein isoform P3, transcribed from for promoter 3.

Impact of Robotic Assisted Surgery on Outcomes in Total Hip Arthroplasty.

BACKGROUND: The introduction of robotic technologies into the field of arthroplasty ushered in promises of increased precision and superior outcomes over conventional methods. However, the effect on outcomes in total hip arthroplasty (THA) remains debatable, particularly when considering the additional financial burden created by the addition of robotics. The purpose of this study is to examine total cost of care, length of stay (LOS), and postoperative complications in robotic-assisted vs conventional THA recipients. MATERIALS AND METHODS: A retrospective review of the Mariner database was performed within PearlDiver Technologies for patients undergoing THA from 2010 to 2018 (n = 714,859). Patients with robotic-assisted procedures were matched with patients undergoing conventional THA at a 1:1 ratio based on age, sex, Charlson Comorbidity Index, smoking, and obesity status (n = 4630). LOS, total cost of care, readmission rates, and medical and surgical outcomes were examined. RESULTS: Robotic-assisted patients had shorter average LOS (3.4 vs 3.7 days, P = .001). The mean cost for robotic-assisted patients was $1684 and $1759 less at 90 days and 1 year, respectively (both P = .001). Readmission rates were higher for robotic-assisted patients at 1 year (7.8 vs 6.6%; P = .001), while surgical outcomes were not significantly different at all timepoints (all P > .498). Robotic-assisted patients demonstrated significantly higher blood transfusion rates (4.4 vs 3.2%; P = .001). CONCLUSIONS: Robotic-assisted THA was associated with minimal decreases in LOS and costs as compared to conventional methods. However, robotics was associated with slightly higher readmissions and blood transfusions.

How Does Conversion Total Hip Arthroplasty Compare to Primary?

BACKGROUND: Recent institutional evidence suggests that conversion total hip arthroplasty (THA) incurs higher complication rates and costs when compared to primary THA. These findings contrast with the current reimbursement system as conversion and primary THAs are classified under the same diagnosis-related group. Thus, a national all-payer database was utilized to compare complication rates up to 2 years, 30-day readmission rates, and 90-day costs between conversion THA and matched primary THA patients. METHODS: A retrospective review of the PearlDiver database between 2010 and second quarter of 2018 was performed using Current Procedural Terminology (CPT) codes to compare conversion THA (CPT 27132) to primary THA (CPT 27130). Patients were matched at a 1:3 ratio based on age, gender, Charlson Comorbidity Index, body mass index, tobacco use, and diabetes (conversion = 8369; primary = 25,081 patients). RESULTS: Conversion THA had higher rates of periprosthetic joint infections (conversion: 7.7% vs primary: 1.4%), hip dislocations (4.5% vs 2.0%), blood transfusions (2.0% vs 1.0%), mechanical complications (5.5% vs 1.0%), and revision surgeries (4.0% vs 1.5%) (P < .001 for all) by 90 days. The 30-day readmission rate for conversion THA was significantly higher compared to the primary group (7.3% vs 3.3%) (P < .001). Median cost at 90 days for conversion THA was significantly higher compared to primary THA ($18,800 vs $13,611, P < .001). CONCLUSION: This study revealed increased complication rates, revisions, readmissions, and costs among conversion THA patients compared to matched primary THA patients. These results support the reclassification of conversion into a diagnosis-related group separate from primary THA.

Osteoarthritis and Osteonecrosis in Total Hip Arthroplasty: 90-Day Postoperative Costs and Outcomes.

BACKGROUND: Two common diagnoses for patients undergoing total hip arthroplasty (THA) are osteoarthritis (OA) and osteonecrosis (ON), pathologically different diseases that affect postoperative complication rates. The underlying pathology of ON may predispose patients to a higher rate of certain complications. Previous research has linked ON with higher mortality and revisions, but a comparison of costs and complication rates may help elucidate further risks. This study reports 90-day costs, lengths of stay (LOS), readmission rates, and complication rates between patients undergoing THA for OA and ON. METHODS: The Nationwide Readmissions Database was retrospectively reviewed for primary THAs, with 90-day readmissions assessed from the index procedure. Patients diagnosed with OA (n = 1,577,991) and ON (n = 55,034) were identified. Costs, LOS, and any readmission within 90 days for complications were recorded and analyzed with the chi-square and t-tests. RESULTS: Patients with ON had higher 90-day costs ($20,110.80 vs. 22,462.79, P < .01) and longer average LOS (3.48 vs. 4.49 days, P < .01). Readmission rates within 90 days of index THA were significantly higher among patients with ON (7.7% vs. 13.1%, P < .01). Patients with OA had a lower incidence of 90-day overall complications (4.1 vs. 6.4%, P < .01). CONCLUSIONS: Patients undergoing THA for ON incur higher readmission-related costs and complication rates. Understanding the predisposing factors for increased complications in ON may improve patient outcomes.

flasher, a novel mutation in a glucosinolate modifying enzyme, conditions changes in plant architecture and hormone homeostasis.

Meristem function is underpinned by numerous genes that affect hormone levels, ultimately controlling phyllotaxy, the transition to flowering and general growth properties. Class I KNOX genes are major contributors to this process, promoting cytokinin biosynthesis but repressing gibberellin production to condition a replication competent state. We identified a suppressor mutant of the KNOX1 mutant brevipedicellus (bp) that we termed flasher (fsh), which promotes stem and pedicel elongation, suppresses early senescence, and negatively affects reproductive development. Map-based cloning and complementation tests revealed that fsh is due to an E40K change in the flavin monooxygenase GS-OX5, a gene encoding a glucosinolate (GSL) modifying enzyme. In vitro enzymatic assays revealed that fsh poorly converts substrate to product, yet the levels of several GSLs are higher in the suppressor line, implicating FSH in feedback control of GSL flux. FSH is expressed predominantly in the vasculature in patterns that do not significantly overlap those of BP, implying a non-cell autonomous mode of meristem control via one or more GSL metabolites. Hormone analyses revealed that cytokinin levels are low in bp, but fsh restores cytokinin levels to near normal by activating cytokinin biosynthesis genes. In addition, jasmonate levels in the fsh suppressor are significantly lower than in bp, which is likely due to elevated expression of JA inactivating genes. These observations suggest the involvement of the GSL pathway in generating one or more negative effectors of growth that influence inflorescence architecture and fecundity by altering the balance of hormonal regulators.