New CMS Merit-Based Incentive Payment System Value Pathway After Total Knee and Hip Arthroplasty: Preparing for Mandatory Reporting.

This article discusses the implementation of a new Merit-Based Incentive Payment System Value Pathway (MVPs) applicable to elective total hip and total knee arthroplasty as created by Medicare and Medicaid Services (CMS) - the Improving Care for Lower Extremity Joint Repair MVP (MVP ID: G0058). We describe specific quality measures, surgeon-hospital collaborations, future developments with Quality Payment Program, and how lessons from early implementation will empower clinicians to participate in the refining of this MVP. The CMS has designed MVPs as a subset of measures relevant to a specialty or medical condition, in an effort to reduce the burden of reporting and improve assessment of care quality. Physicians and payors must be mindful of detrimental effects these measures in their current form may have on surgeons, institutions, and patients, including disincentivizing care for sicker or more vulnerable populations, and increased administrative costs. Early voluntary participation is crucial to gain valuable experience for the orthopedic community and in an effort to work alongside CMS to maximize care while minimizing cost for patients and burden for providers.

Implementation of the New Medicare-Mandated Patient-Reported Outcomes After Joint Arthroplasty Performance Measure.

A new mandatory hospital-level, risk-standardized performance measure for elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) based on patient-reported outcomes (THA/TKA PRO-PM) has been implemented by the Centers for Medicare & Medicaid Services (CMS). All THA and TKA in Medicare fee-for-service beneficiaries at inpatient facilities are included. The THA/TKA PRO-PM is the proportion of risk-standardized THA or TKA patients meeting or exceeding the substantial clinical benefit threshold between preoperative and postoperative outcomes measures (Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement, Knee injury and Osteoarthritis Outcome Score for Joint Replacement). This binary outcome (yes/no) is then divided by all eligible patients creating a percentage of patients reaching substantial clinical benefit. The percentile score among hospitals will be reported. Following 2 voluntary reporting periods, mandatory reporting will begin in 2025. The CMS requires 50% reporting rates; failure leads to annual payment reduction in fiscal year 2028. The CMS intends the THA/TKA PRO-PM to be a patient-centered, meaningful, and relatable measure of hospital performance reported to the public. For surgeons, this is an opportunity to collaborate with hospitals for developing and implementing a THA/TKA data collection system to avoid penalties for the hospital. Further implementation for outpatient surgery and in ambulatory surgery centers has been announced by CMS. Major resources will be needed to succeed in the expected capture rates.

Mapping the course to recovery: a prospective study on the anatomic distribution of early postoperative pain after total knee arthroplasty.

INTRODUCTION: Early postoperative pain following total knee arthroplasty significantly impacts outcomes and patient satisfaction. However, the characteristics and sources of early pain after total knee arthroplasty remain unclear. Therefore, the purpose of this study was to determine the anatomic distribution and course of postoperative pain in the acute and subacute period following total knee arthroplasty. METHODS: A prospective observational study of primary, elective unilateral total knee arthroplasty cases was conducted at our academic tertiary care medical center from January 2021 to September 2021. Preoperative variables were extracted from institutional electronic medical records. Postoperatively, patients utilized a knee pain map to identify the two locations with the most significant pain and rated it using the visual analog scale (VAS). The data were collected on day 0, at 2 weeks, 2 months, and 6 months after operation. RESULTS: This study included 112 patients, with 6% of patients having no pain at postoperative day 0, 22% at 2 weeks, 46% at 2 months, and 86% at 6 months after operation. In those who reported pain, the VAS score (mean ± standard deviation) was 5.8 ± 2.4 on postoperative day 0 and decreased at each follow-up time point (5.4 ± 2.3 at 2 weeks, 3.9 ± 2.2 at 2 months, and 3.8 ± 2.7 at 6 months). The majority of patients were able to identify distinct loci of pain. The most common early pain loci were patellae, thigh, and medial joint line, and this distribution dissipated by 6 months. CONCLUSION: At 2 postoperative weeks, pain was primarily at the medial joint, and at 6 months postoperatively, pain was more likely to be at the lateral joint. No relationship was found between pain at six months and pain scores or location at postoperative day 0 or 2 weeks. Understanding the distribution and progression of knee pain following total knee arthroplasty may benefit patient education and targeted interventions. LEVEL OF EVIDENCE: Level II, prospective observational study.

Comparing Pain and Pain Coping Mechanisms in Patients Undergoing Total Joint Arthroplasty as Part of a Mission Trip to Those in the United States.

BACKGROUND: Access to total joint arthroplasty can be difficult in low-resource settings. Service trips are conducted to provide arthroplasty care to populations in need around the world. This study aimed to compare the pain, function, surgical expectations, and coping mechanisms of patients from one such service trip to the United States. METHODS: In 2019, the Operation Walk program conducted a service trip in Guyana during which 50 patients had hip or knee arthroplasties. Patient demographics, patient-reported outcome measures, questionnaires assessing pain attitudes and coping, and pain visual analog scales were collected preoperatively and at 3 months postoperatively. These outcomes were compared with a matched cohort of elective total joint arthroplasty at a US tertiary care medical center. There were 37 patients matched between the 2 cohorts. RESULTS: The mission cohort had significantly lower preoperative self-reported function scores than the US cohort (38.3 versus 47.5, P = .003), as well as a significantly larger improvement at 3 months (42.4 versus 26.4, P = .014). The mission cohort had significantly higher initial pain (8.0 versus 7.0, P = .015), but there were no differences with regard to pain at 3 months (P = .420) or change in pain (P = .175). The mission cohort had significantly greater preoperative scores in pain attitude and coping responses. CONCLUSION: Patients in low-resource settings were more likely to have preoperative functional limitations and pain, and they coped with pain through prayer. Understanding the key differences between these 2 types of populations and how they approach pain and functional limitations may help improve care for each group. LEVEL OF EVIDENCE: II, prospective study.

Preoperative Anemia is an Independent Risk Factor for Increased Complications and Mortalities After Total Knee Arthroplasty Regardless of Postoperative Transfusions.

BACKGROUND: Preoperative anemia is associated with adverse events following total knee arthroplasty (TKA). It remains unknown if this effect is due to comorbid conditions, adverse events associated with transfusions, or the anemia itself. We used propensity-score matching to isolate the effect of anemia on postoperative complications following TKA, regardless of blood transfusions. METHODS: Patients undergoing primary TKA from 2010 to 2020 without receiving a perioperative blood transfusion, were identified using a large national database. A 1:1 propensity score matching was used to create cohorts of anemic and nonanemic patients matched on Charlson Comorbidity Index (CCI), American Society of Anesthesiology (ASA) classification, age, sex, and prevalence of bleeding disorders. There were 43,370 patients were included in each group (mean age 68 [range, 29 to 99; 44% male]). The 1:1 matching yielded groups with similar CCI, ASA classification, age, sex, and prevalence of bleeding disorders (all, P > .9). RESULTS: Anemic patients had a higher incidence of major complications (4.1 versus 2.8%; P < .001), 30-day mortality rate (0.2 versus 0.1%; P < .001), and extended lengths of stay (LOS) (8.3 versus 6.6%; P < .001). Anemic patients also had increased 30-day rates of wound infection requiring hospital admission, renal failure, reintubation, myocardial infarction, and pneumonia (all, P < .001). CONCLUSION: In matched cohorts of anemic versus nonanemic patients undergoing TKA, all who had no postoperative blood transfusion, anemic patients had higher rates of complications, extended LOS, and mortalities. Thus, anemia should be considered an independent risk factor for complications following TKA.

Determining a preoperative international normalised ratio threshold safe for hip fracture surgery.

INTRODUCTION: The purpose of this study was first, to assess the relationship between preoperative INR (international normalised ratio) and postoperative complication rates in patients with a hip fracture, and second, to establish a threshold for INR below which the risk of complications is comparable to those in patients with a normal INR. METHODS: We retrospectively reviewed the American College of Surgeons National Surgical Quality Improvement Program and found 35,910 cases who had undergone surgery for a hip fracture between 2012 and 2018. Cases were stratified into 4 groups based on their preoperative INR levels: <1.4; ⩾1.4 and <1.6; ⩾1.6 and <1.8 and ⩾1.8. These cohorts were assessed for differences in preoperative factors, intraoperative factors, and postoperative course. Multivariate logistic regression was used to assess the risk of transfusion, 30-day mortality, cardiac complications, and wound complications adjusting for all preoperative and intraoperative factors. RESULTS: Of the 35,910 cases, 33,484 (93.2%) had a preoperative INR < 1.4; 867 (2.4%) an INR ⩾1.4 and <1.6; 865 (2.4%) an INR ⩾ 1.6 and <1.8 and 692 (1.9%) an INR ⩾ 1.8. A preoperative INR ⩾ 1.8 was independently associated with an increased risk of bleeding requiring transfusion. A preoperative INR ⩾ 1.6 was associated with an increased risk of mortality. CONCLUSIONS: We found that an INR of <1.6 is a safe value for patients who are to undergo surgery for a hip fracture. Below this value, patients avoid an increased risk of both transfusion and 30-day mortality seen with higher INR values. These findings may allow adjustment of preoperative protocols and improve the outcome of hip fracture surgery in this group of patients.

Transfusion Rates in the Operative Treatment of Prosthetic Hip and Knee Infection.

Surgery for prosthetic joint infection (PJI) can often lead to significant blood loss, necessitating allogeneic blood transfusion (ABT). The use of ABT is associated with higher rates of morbidity and death in revision total joint arthroplasty, particularly in the treatment of PJI. We compared ABT rates by procedure type among patients treated for PJI. We retrospectively reviewed 143 operative cases of hip and knee PJI performed at our institution between 2016 and 2018. Procedures were categorized as irrigation and debridement (I&D) with modular component exchange (modular component exchange), explantation with I&D and placement of an antibiotic spacer (explantation), I&D with antibiotic spacer exchange (spacer exchange), or antibiotic spacer removal and prosthetic reimplantation (reimplantation). Rates of ABT and the number of units transfused were assessed. Factors associated with ABT were assessed with a multilevel mixed-effects regression model. Of the cases, 77 (54%) required ABT. The highest rates of ABT occurred during explantation (74%) and spacer exchange (72%), followed by reimplantation (36%) and modular component exchange (33%). A lower preoperative hemoglobin level was associated with higher odds of ABT. Explantation, reimplantation, and spacer exchange were associated with greater odds of ABT. Antibiotic spacer exchange and explantation were associated with greater odds of multiple-unit transfusion. Rates of ABT remain high in the surgical treatment of PJI. Antibiotic spacer exchange and explantation procedures had high rates of multiple-unit transfusions, and additional units of blood should be made available. Preoperative anemia should be treated when possible, and further refinement of blood management protocols for prosthetic joint infection is necessary. [Orthopedics. 2022;45(6):353-359.].

The Efficacy and Safety of Corticosteroids in Total Joint Arthroplasty: A Direct Meta-Analysis.

BACKGROUND: Corticosteroids are commonly used intraoperatively to treat pain and reduce opioid consumption and nausea associated with primary total joint arthroplasty (TJA). The purpose of this study was to evaluate the efficacy and safety of corticosteroids in primary TJA to support the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and the American Society of Regional Anesthesia and Pain Management. METHODS: The MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases were searched for studies published before February 2020 on corticosteroids in TJA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of corticosteroids. RESULTS: Critical appraisal of 1,581 publications revealed 23 studies regarded as the best available evidence for analysis. Intraoperative dexamethasone reduces postoperative pain, opioid consumption, and nausea and vomiting. Multiple doses lead to further reduction in pain, opioid consumption, nausea and vomiting. There is insufficient evidence on the risk of adverse events with perioperative dexamethasone in TJA. CONCLUSION: Strong evidence supports the use of a single dose or multiple doses of intravenous dexamethasone to reduce postoperative pain, opioid consumption, nausea and vomiting after primary TJA. There is insufficient evidence on perioperative dexamethasone in primary TJA to determine the optimal dose, number of doses, or risk of postoperative adverse events.

Preoperative Patient Optimization in Total Joint Arthroplasty-The Paradigm Shift from Preoperative Clearance: A Narrative Review.

Background: Total joint arthroplasty (TJA) is one of the most common procedures performed in the United States. Outcomes of this elective procedure may be improved via preoperative optimization of modifiable risk factors. Purposes: We sought to summarize the literature on the clinical implications of preoperative risk factors in TJA and to develop recommendations regarding preoperative optimization of these risk factors. Methods: We searched PubMed in August 2019 with an update in September 2020 for English-language, peer-reviewed publications assessing the influence on outcomes in total hip and knee replacement of 7 preoperative risk factors-obesity, malnutrition, hypoalbuminemia, diabetes, anemia, smoking, and opioid use-and recommendations to mitigate them. Results: Sixty-nine studies were identified, including 3 randomized controlled trials, 8 prospective cohort studies, 42 retrospective studies, 6 systematic reviews, 3 narrative reviews, and 7 consensus guidelines. These studies described worse outcomes associated with these 7 risk factors, including increased rates of in-hospital complications, transfusions, periprosthetic joint infections, revisions, and deaths. Recommendations for strategies to screen and address these risk factors are provided. Conclusions: Risk factors can be optimized, with evidence suggesting the following thresholds prior to surgery: a body mass index <40 kg/m2, serum albumin ≥3.5 g/dL, hemoglobin A1C ≤7.5%, hemoglobin >12.0 g/dL in women and >13.0 g/dL in men, and smoking cessation and ≥50% decrease in opioid use by 4 weeks prior to surgery. Surgery should be delayed until these risk factors are adequately optimized.

Increased Patient-Level Payment After Removal of Total Knee Arthroplasty From the Inpatient-Only List.

BACKGROUND: In January 2018, the Centers for Medicare and Medicaid Services removed total knee arthroplasty (TKA) from the Inpatient Only (IPO) list. This study aimed to compare patient-level payments in TKA cases with a length of stay (LOS) <2 midnights before and after removal of TKA from IPO list. METHODS: In this retrospective cohort study, all Medicare patients who received a primary elective TKA from 2016-2019 with a LOS <2 midnights at an academic tertiary center were identified. Total and itemized charges and patient-level payments were compared between eligible TKA cases performed in 2016-2017 and those in 2018-2019. There were 351 eligible TKA cases identified: 151 in 2016-2017 and 200 in 2018-2019. RESULTS: The percentage of patients making any out-of-pocket payment increased in 2018-2019 from 2016-2017 (51.0% versus 10.6%), as did median patient-level payment ($7.30 [range, $0.00-$3,389] versus $0.00 [range, $0.00-$1,248], P < .001 for both). A greater proportion of patients in 2018-2019 paid $1-$50 than in 2016-2017 (37.5% versus 1.3%, P < .001) with no change in the proportion of patients who made payments >$50. Total charges were less in 2018-2019 than in 2016-2017 (P = .001). Charges for drugs, laboratory tests, admissions/floor, and therapies decreased in 2018-2019, whereas charges for the operating room and radiology increased (P < .001 for all). CONCLUSION: Patients receiving outpatient TKA in 2018-2019 were more likely to have out-of-pocket payments than patients with comparable hospital stay who were designated as inpatients, although most of these payments were less than $50.

Multimodal prediction of pain and functional outcomes 6 months following total knee replacement: a prospective cohort study.

BACKGROUND: Knee osteoarthritis (OA) is among the most common and disabling persistent pain conditions, with increasing prevalence and impact around the globe. In the U.S., the rising prevalence of knee OA has been paralleled by an increase in annual rates of total knee arthroplasty (TKA), a surgical treatment option for late-stage knee OA. While TKA outcomes are generally good, post-operative trajectories of pain and functional status vary substantially; a significant minority of patients report ongoing pain and impaired function following TKA. A number of studies have identified sets of biopsychosocial risk factors for poor post-TKA outcomes (e.g., comorbidities, negative affect, sensory sensitivity), but few prospective studies have systematically evaluated the unique and combined influence of a broad array of factors. METHODS: This multi-site longitudinal cohort study investigated predictors of 6-month pain and functional outcomes following TKA. A wide spectrum of relevant biopsychosocial predictors was assessed preoperatively by medical history, patient-reported questionnaire, functional testing, and quantitative sensory testing in 248 patients undergoing TKA, and subsequently examined for their predictive capacity. RESULTS: The majority of patients had mild or no pain at 6 months, and minimal pain-related impairment, but approximately 30% reported pain intensity ratings of 3/10 or higher. Reporting greater pain severity and dysfunction at 6 months post-TKA was predicted by higher preoperative levels of negative affect, prior pain history, opioid use, and disrupted sleep. Interestingly, lower levels of resilience-related "positive" psychosocial characteristics (i.e., lower agreeableness, lower social support) were among the strongest, most consistent predictors of poor outcomes in multivariable linear regression models. Maladaptive profiles of pain modulation (e.g., elevated temporal summation of pain), while not robust unique predictors, interacted with psychosocial risk factors such that the TKA patients with the most pain and dysfunction exhibited lower resilience and enhanced temporal summation of pain. CONCLUSIONS: This study underscores the importance of considering psychosocial (particularly positively-oriented resilience variables) and sensory profiles, as well as their interaction, in understanding post-surgical pain trajectories.

Incidence and risk factors for perioperative death after revision total hip arthroplasty: a 20-year analysis.

INTRODUCTION: The number of revision total hip arthroplasty (THA) procedures is increasing in the US. Revision THA is associated with higher complication rates compared with primary THA. We describe patterns in incidence and risk factors for perioperative death after revision THA. METHODS: Using the National Hospital Discharge Survey, we identified nearly 700,000 cases of revision THA from 1990 through 2010. Procedure incidence, perioperative mortality rates, comorbidities, discharge disposition, and duration of hospital stay were analysed. Multivariable logistic regression was used to identify independent risk factors for perioperative death. Alpha = 0.01. RESULTS: Population-adjusted incidence of revision THA per 100,000 people increased from 9.2 cases in 1990 to 15 cases in 2010 (p < 0.001). The rate of perioperative death was 0.9% during the study period and decreased from 1.5% during the "first" period (1990-1999) to 0.5% during the "second" period (2000-2010) (p < 0.001), despite an increase in comorbidity burden over time. Factors associated with the greatest odds of perioperative death were acute myocardial infarction (odds ratio [OR], 37; 95% confidence interval [CI], 33-40; p < 0.001), pneumonia (OR, 16; 95% CI, 15-18; p < 0.001), and pulmonary embolism (OR, 13; 95% CI, 11-15; p < 0.001). CONCLUSIONS: The rate of perioperative death in patients undergoing revision THA in the US decreased from 1990 to 2010 despite an increase in comorbidities. Acute myocardial infarction, pneumonia, and pulmonary embolism were associated with the highest odds of perioperative death after revision THA.

Predictors and Outcomes of Postoperative Hemoglobin of <8 g/dL in Total Joint Arthroplasty.

BACKGROUND: Restrictive transfusion practices have decreased transfusions in total joint arthroplasty (TJA). A hemoglobin threshold of <8 g/dL is commonly used. Predictors of this degree of postoperative anemia in TJA and its association with postoperative outcomes, independent of transfusions, remain unclear. We identified predictors of postoperative hemoglobin of <8 g/dL and outcomes with and without transfusion in TJA. METHODS: Primary elective TJA cases performed with a multimodal blood management protocol from 2017 to 2018 were reviewed, identifying 1,583 cases. Preoperative and postoperative variables were compared between patients with postoperative hemoglobin of <8 and ≥8 g/dL. Logistic regression and receiver operating characteristic curves were used to assess predictors of postoperative hemoglobin of <8 g/dL. RESULTS: Positive predictors of postoperative hemoglobin of <8 g/dL were preoperative hemoglobin level (odds ratio [OR] per 1.0-g/dL decrease, 3.0 [95% confidence interval (CI), 2.4 to 3.7]), total hip arthroplasty (OR compared with total knee arthroplasty, 2.1 [95% CI, 1.3 to 3.4]), and operative time (OR per 30-minute increase, 2.0 [95% CI, 1.6 to 2.6]). Negative predictors of postoperative hemoglobin of <8 g/dL were tranexamic acid use (OR, 0.42 [95% CI, 0.20 to 0.85]) and body mass index (OR per 1 kg/m2 above normal, 0.90 [95% CI, 0.86 to 0.94]). Preoperative hemoglobin levels of <12.4 g/dL in women and <13.4 g/dL in men best predicted postoperative hemoglobin of <8 g/dL. Overall, 5.2% of patients with postoperative hemoglobin of 7 to 8 g/dL and 95% of patients with postoperative hemoglobin of <7 g/dL received transfusions. Patients with postoperative hemoglobin of <8 g/dL had longer hospital stays (p < 0.001) and greater rates of emergency department visits or readmissions (p = 0.001) and acute kidney injury (p < 0.001). Among patients with postoperative hemoglobin of <8 g/dL, patients who received transfusions had a lower postoperative hemoglobin nadir (p < 0.001) and a longer hospital stay (p = 0.035) than patients who did not receive transfusions. CONCLUSIONS: Postoperative hemoglobin of <8 g/dL after TJA was associated with worse outcomes, even for patients who do not receive transfusions. Optimizing preoperative hemoglobin levels may mitigate postoperative anemia and adverse outcomes. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Sex Differences in Recovery Across Multiple Domains Among Older Adults With Hip Fracture.

BACKGROUND: Hip fractures are a public health problem among older adults, but most research on recovery after hip fracture has been limited to females. With growing numbers of hip fractures among males, it is important to determine how recovery outcomes may differ between the sexes. METHODS: 168 males and 171 females were enrolled within 15 days of hospitalization with follow-up visits at 2, 6, and 12 months postadmission to assess changes in disability, physical performance, cognition, depressive symptoms, body composition, and strength, and all-cause mortality. Generalized estimating equations examined whether males and females followed identical outcome recovery assessed by the change in each outcome. RESULTS: The mean age at fracture was similar for males (80.4) and females (81.4), and males had more comorbidities (2.5 vs 1.6) than females. Males were significantly more likely to die over 12 months (hazard ratio 2.89, 95% confidence interval: 1.56-5.34). Changes in outcomes were significantly different between males and females for disability, gait speed, and depressive symptoms (p < .05). Both sexes improved from baseline to 6 months for these measures, but only males continued to improve between 6 and 12 months. There were baseline differences for most body composition measures and strength; however, there were no significant differences in change by sex. CONCLUSIONS: Findings confirm that males have higher mortality but suggest that male survivors have continued functional recovery over the 12 months compared to females. Research is needed to determine the underlying causes of these sex differences for developing future prognostic information and rehabilitative interventions.

Septic Arthritis Among Users of Injection Drugs: Clinical Course and Microbial Characteristics.

Injection drug use (IDU) is a risk factor for septic arthritis (SA) of native joints. Amid the opioid crisis, IDU rates have increased. This study assessed differences in pre-operative characteristics, microbial characteristics, and postoperative outcomes of 177 cases of SA treated operatively from 2015 to 2019 at 3 US hospitals, by self-reported IDU status. Forty cases (23%) involved patients who reported IDU. Patient characteristics, comorbidities, microbial characteristics, duration of hospital stay, discharge destination, follow-up rates, and rates of persistent/secondary infection were compared by self-reported IDU status. Compared with non-IDU-associated SA (non-IDU-SA), IDU-associated SA (IDU-SA) was associated with female sex (P=.001), younger age (P<.001), lower body mass index (P<.001), tobacco use (P<.001), and psychiatric diagnosis (P=.04) and was more likely to involve methicillin-resistant Staphylococcus aureus (P<.001). The IDU-SA was associated with discharge to a skilled nursing facility or against medical advice (P<.001) and with loss to follow-up (P=.01). The 2 groups did not differ in terms of American Society of Anesthesiologists classification, joint involved, Gram stain positivity, presence of bacteremia, peripherally inserted central catheter placement, return to hospital within 3 months, or persistent/secondary positive results on culture within 3 months. Patients with IDU-SA were younger, were more likely to be female, had lower body mass index, and had fewer medical comorbidities but were more likely to use tobacco and to have a psychiatric diagnosis compared with patients with non-IDU-SA. Methicillin-resistant S aureus was more common in the IDU-SA group, as was discharge to a skilled nursing facility or against medical advice. Patients with IDU-SA were less likely to return for follow-up than patients with non-IDU-SA. [Orthopedics. 2021;44(6):e747-e752.].

Predilection for developing a hematogenous orthopaedic implant-associated infection in older versus younger mice.

BACKGROUND: The pathogenesis of hematogenous orthopaedic implant-associated infections (HOIAI) remains largely unknown, with little understanding of the influence of the physis on bacterial seeding. Since the growth velocity in the physis of long bones decreases during aging, we sought to evaluate the role of the physis on influencing the development of Staphylococcus aureus HOIAI in a mouse model comparing younger versus older mice. METHODS: In a mouse model of HOIAI, a sterile Kirschner wire was inserted retrograde into the distal femur of younger (5-8-week-old) and older (14-21-week-old) mice. After a 3-week convalescent period, a bioluminescent Staphylococcus aureus strain was inoculated intravenously. Bacterial dissemination to operative and non-operative legs was monitored longitudinally in vivo for 4 weeks, followed by ex vivo bacterial enumeration and X-ray analysis. RESULTS: In vivo bioluminescence imaging and ex vivo CFU enumeration of the bone/joint tissue demonstrated that older mice had a strong predilection for developing a hematogenous infection in the operative legs but not the non-operative legs. In contrast, this predilection was less apparent in younger mice as the infection occurred at a similar rate in both the operative and non-operative legs. X-ray imaging revealed that the operative legs of younger mice had decreased femoral length, likely due to the surgical and/or infectious insult to the more active physis, which was not observed in older mice. Both age groups demonstrated substantial reactive bone changes in the operative leg due to infection. CONCLUSIONS: The presence of an implant was an important determinant for developing a hematogenous orthopaedic infection in older but not younger mice, whereas younger mice had a similar predilection for developing periarticular infection whether or not an implant was present. On a clinical scale, diagnosing HOIAI may be difficult particularly in at-risk patients with limited examination or other data points. Understanding the influence of age on developing HOIAI may guide clinical surveillance and decision-making in at-risk patients.

Perceptions of Financial Conflict of Interest and Knowledge of the Sunshine Act Among Orthopedic Surgery Patients.

The orthopedic surgical specialty is strongly tied to partnerships with industry that have fostered innovation and greatly enhanced patient care. A substantial number of orthopedic surgeons currently receive some form of industry support. These relationships are highly scrutinized because they present the possibility of both personal and financial conflicts of interest (COI). The authors examined orthopedic patients' awareness of existing regulation and perceptions of financial COI by performing a prospective survey-based study of patients seen in an academic orthopedic department. Data were collected during 1 year, in a cross-section of hospital-based and community clinical settings. The authors collected 513 surveys during a 1-year period between 4 clinical locations. Of all respondents, 55% were unconcerned regarding gifts or direct compensation their physicians received from industry, and only 16% were very or extremely concerned regarding these benefits. Patients' opinions regarding possible influence of benefits were similarly ambivalent, with 54% of patients minimally or not at all concerned regarding the potential influence of industry gifts or compensation. Seventy-six percent of patients had never heard of the Sunshine Act, and only 3% indicated that they were aware of the legislation and its intention. The income of the respondents and their level of education were positively correlated with increased concern about handling of COI, as well as knowledge regarding the Sunshine Act. These data suggest that orthopedic surgery patients are widely unconcerned regarding physician COI, but specific subsets of patients may be more likely to have concerns regarding these relationships. [Orthopedics. 2021;44(5):e682-e686.].