MCID achievement in staged bilateral total knee arthroplasty: Are both joints created equal?

BACKGROUND: A notable portion of unilateral total knee arthroplasty (TKA) patients undergo arthroplasty of the contralateral knee. The aims of this study were to describe the Minimal Clinically Important Difference for Improvement (MCID-I) and Worsening (MCID-W) in staged bilateral TKAs (BTKAs) and identify factors associated with these outcomes. METHODS: Patients with staged BTKA were retrospectively reviewed. Demographics, surgery details, and Patient-Reported Outcome Measurement Information System Physical Function Short Form 10a (PROMIS PF10a) were collected. MCID-I and MCID-W were defined for PROMIS PF10a. Patients were stratified into nine groups based on the MCID achievement of the first and second TKA: (A) MCID-I, MCID- I, (B) MCID-I, Neutral, (C) MCID-I, MCID-W, (D) Neutral, MCID-I, (E) Neutral, Neutral, (F) Neutral, MCID-W, (G) MCID- W, MCID-I, (H) MCID-W, Neutral, (I) MCID-W, MCID-W. Neutral patients did not achieve either MCID-I or MCID-W. RESULTS: The final cohort consisted of 59 staged BTKA patients. In patients who achieved MCID-I in the first TKA, 39.1% achieved MCID-I again in the second TKA (A), 39.1% were neutral (B), and 21.7% achieved MCID-W (C) in the second TKA. However, 77.8% of those who achieved MCID-W in the first joint (n = 9) went on to achieve MCID-I (G) in the second TKA. Those who achieved MCID-I after both TKAs (A) had a longer staged interval than those who achieved first MCID-I, then MCID-W (C) (15 months vs 8 months, P = 0.0113). CONCLUSION: In staged BTKA, MCID achievement of the first TKA may not be associated with the outcome of the second TKA.

The Role of Risk Tolerance in a Patient's Decision to Undergo Total Knee and Hip Arthroplasty.

BACKGROUND: A patient's decision-making process to undergo surgery is crucial for surgeons to understand for patient-counseling purposes. Total knee and hip arthroplasty, like any other major surgery, is associated with serious, sometimes life-threatening, complications. Using the results of discrete choice experiments (DCEs), we aimed to understand the relationship between a patient's risk tolerance and choosing to undergo surgery in real life. METHODS: This is a retrospective study of prospectively collected DCE results for 142 potential knee or hip arthroplasty clinic patients from October 2021 to March 2022. The DCE presented the patient with 2 scenarios, each of which was made up of different combinations of attributes and levels. A hierarchal Bayesian model was used to obtain a risk score that reflected the risk attributes chosen by each patient. Logistic regressions were then used to evaluate the association between a patient's willingness to incur risk and their decision to undergo a total joint arthroplasty. RESULTS: Of the 142 patients enrolled in the DCE, 89 (62.3%) underwent a total joint arthroplasty. Risk score (odds ratio [OR] = 2.6, 95% confidence interval [CI] 1.1 to 6.6, P = 0.04), men (OR = 2.5, 95% CI 1.1 to 5.9, P = 0.028), and patients who have hip osteoarthritis (OR = 2.4, 95% CI 1.1 to 5.5, P = 0.036) increased the odds of undergoing arthroplasty, whereas physical function of at least 75% at the initial visit (OR = 0.3, 95% CI 0.1 to 0.7, P = 0.004) decreased these odds. CONCLUSIONS: We found that a patient's willingness to incur risk, lower baseline physical function, and men were all independently associated with undergoing total knee arthroplasty. We believe that these findings prompt much-needed future studies that focus solely on the relationship between patients' inherent risk behavior and surgical and patient-reported outcomes.

Dual Surgical Setup Associated with Reduced Infection Recurrence for Hip and Knee Arthroplasty After Two-Stage Exchange.

INTRODUCTION: Two-stage exchange (TSE) is the gold standard for the treatment of chronic periprosthetic joint infection (PJI) after total joint arthroplasty of the hip and knee in the United States. Failure of treatment can have devastating consequences for the patient, including poor functional outcomes, multiple further surgeries, and increased mortality. Several factors associated with infection recurrence have previously been identified in the literature. The purpose of this study was to evaluate whether the use of a dual surgical setup was associated with reduced risk of recurrence after TSE for PJI. METHODS: A retrospective study was conducted between January 2000 and December 2021 to isolate patients who underwent TSE after total joint arthroplasty of the hip and knee. Failure was defined as infection recurrence requiring surgical intervention. Demographic factors (age, sex, body mass index, smoking status, American Society of Anesthesiologists status), preoperative comorbidities (hypertension, cardiac disease, diabetes status, depression diagnosis, pulmonary disease), operating surgeon, single versus dual setup, hospital setting, use of long-term antibiotics postoperatively after TSE, aspiration data, and infecting organism were compared between cohorts using multivariate regression analysis. RESULTS: A total of 134 patients were identified who underwent TSE after diagnosis of PJI. The mean follow-up was 67.84 (range, 13 to 236) months. Dual setup (odds ratio, 0.13; confidence interval, 0.02 to 0.52; P = 0.0122) was found to be an independent predictive variable associated with a lower risk of infection recurrence. CONCLUSION: Utilization of a dual surgical setup is a low-cost modifiable risk factor associated with a lower risk of recurrence of after TSE of the hip and knee for PJI.

Mental Robustness May Be Associated With Improved Physical Function in Bilateral Total Knee Arthroplasty Patients.

BACKGROUND: In accordance with the high incidence of bilateral knee osteoarthritis, many patients have undergone bilateral total knee arthroplasty (BTKA). Whether patients undergo bilateral procedures in a staged or simultaneous fashion, the physical and mental burden of undergoing 2 major orthopedic procedures is considerable. The aims of this study were to (1) investigate differences between minimal clinically important difference (MCID) achievement between staged versus simultaneous BTKA, and (2) identify the patient variables, specifically mental scores, that were associated with MCID achievement in patients undergoing BTKA. METHODS: Simultaneous and staged BTKA patients within a single health care network from 2016 to 2021 were retrospectively reviewed. Patient demographics, surgery details, and Patient-Reported Outcome Measurement Information System Physical Function Short Forms 10a (PROMIS PF10a), PROMIS Mental scores, and Knee Disability Osteoarthritis Outcome Scores (KOOS) were reviewed. Preoperative and postoperative patient-reported outcome measures were collected before the first total knee arthroplasty (TKA) and after the second TKA, respectively, in staged BTKA patients. The final cohort consisted of 249 patients, with an average age of 66 years (range, 21 to 87), 63% women, and an average body mass index of 32 (range, 20 to 52), at a mean follow-up of 1.1 years (range, 0.5 to 2.4). Multivariate regressions were performed on MCID PF10a and KOOS achievement, as well as whether the BTKA was performed simultaneously versus staged. RESULTS: A preoperative PROMIS Mental score in the upper 2 quartiles was associated with MCID PF10a achievement in BTKA. Men and surgeries performed at an Academic Medical Center were negatively associated with the achievement of MCID KOOS. Interestingly, those who underwent simultaneous BTKA were less likely to achieve MCID KOOS than those who underwent a staged BTKA. CONCLUSIONS: Preoperative mental robustness may be positively associated with improved physical function outcome in BTKA patients.

Which Factors Are Considered by Patients When Considering Total Joint Arthroplasty? A Discrete-choice Experiment.

BACKGROUND: TKA and THA are major surgical procedures, and they are associated with the potential for serious, even life-threatening complications. Patients must weigh the risks of these complications against the benefits of surgery. However, little is known about the relative importance patients place on the potential complications of surgery compared with any potential benefit the procedures may achieve. Furthermore, patient preferences may often be discordant with surgeon preferences regarding the treatment decision-making process. A discrete-choice experiment (DCE) is a quantitative survey technique designed to elicit patient preferences by presenting patients with two or more hypothetical scenarios. Each scenario is composed of several attributes or factors, and the relative extent to which respondents prioritize these attributes can be quantified to assess preferences when making a decision, such as whether to pursue lower extremity arthroplasty. QUESTIONS/PURPOSES: In this DCE, we asked: (1) Which patient-related factors (such as pain and functional level) and surgery-related factors (such as the risk of infection, revision, or death) are influential in patients' decisions about whether to undergo lower extremity arthroplasty? (2) Which of these factors do patients emphasize the most when making this decision? METHODS: A DCE was designed with the following attributes: pain; physical function; return to work; and infection risks, reoperation, implant failure leading to premature revision, deep vein thrombosis, and mortality. From October 2021 to March 2022, we recruited all new patients to two arthroplasty surgeons' clinics who were older than 18 years and scheduled for a consultation for knee- or hip-related complaints who had no previous history of a primary TKA or THA. A total of 56% (292 of 517) of new patients met the inclusion criteria and were approached with the opportunity to complete the DCE. Among the cohort, 51% (150 of 292) of patients completed the DCE. Patients were administered the DCE, which consisted of 10 hypothetical scenarios that had the patient decide between a surgical and nonsurgical outcome, each consisting of varying levels of eight attributes (such as infection, reoperation, and ability to return to work). A subsequent demographic questionnaire followed this assessment. To answer our first research question about the patient-related and surgery-related factors that most influence patients' decisions to undergo lower extremity arthroplasty, we used a conditional logit regression to control for potentially confounding attributes from within the DCE and determine which variables shifted a patient's determination to pursue surgery. To answer our second question, about which of these factors received the greatest priority by patients, we compared the relevant importance of each factor, as determined by each factor's beta coefficient, against each other influential factor. A larger absolute value of beta coefficient reflects a relatively higher degree of importance placed on a variable compared with other variables within our study. Of the respondents, 57% (85 of 150) were women, and the mean age at the time of participation was 64 ± 10 years. Most respondents (95% [143 of 150]) were White. Regarding surgery, 38% (57 of 150) were considering THA, 59% (88 of 150) were considering TKA, and 3% (5 of 150) were considering both. Among the cohort, 49% (74 of 150) of patients reported their average pain level as severe, or 7 to 10 on a scale from 0 to 10, and 47% (71 of 150) reported having 50% of full physical function. RESULTS: Variables that were influential to respondents when deciding on lower extremity total joint arthroplasty were improvement from severe pain to minimal pain (ß coefficient: -0.59 [95% CI -0.72 to -0.46]; p < 0.01), improvement in physical function level from 50% to 100% (ß: -0.80 [95% CI -0.9 to -0.7]; p < 0.01), ability to return to work versus inability to return (ß: -0.38 [95% CI -0.48 to -0.28]; p < 0.01), and the surgery-related factor of risk of infection (ß: -0.22 [95% CI -0.30 to -0.14]; p < 0.01). Improvement in physical function from 50% to 100% was the most important for patients making this decision because it had the largest absolute coefficient value of -0.80. To improve physical function from 50% to 100% and reduce pain from severe to minimal because of total joint arthroplasty, patients were willing to accept a hypothetical absolute (and not merely an incrementally increased) 37% and 27% risk of infection, respectively. When we stratified our analysis by respondents' preoperative pain levels, we identified that only patients with severe pain at the time of their appointment found the risk of infection influential in their decision-making process (ß: -0.27 [95% CI -0.37 to -0.17]; p = 0.01) and were willing to accept a 24% risk of infection to improve their physical functioning from 50% to 100%. CONCLUSION: Our study revealed that patients consider pain alleviation, physical function improvement, and infection risk to be the most important attributes when considering total joint arthroplasty. Patients with severe baseline pain demonstrated a willingness to take on a hypothetically high infection risk as a tradeoff for improved physical function or pain relief. Because patients seemed to prioritize postoperative physical function so highly in our study, it is especially important that surgeons customize their presentations about the likelihood an individual patient will achieve a substantial functional improvement as part of any office visit where arthroplasty is discussed. Future studies should focus on quantitatively assessing patients' understanding of surgical risks after a surgical consultation, especially in patients who may be the most risk tolerant. CLINICAL RELEVANCE: Surgeons should be aware that patients with the most limited physical function and the highest baseline pain levels are more willing to accept the more potentially life-threatening and devastating risks that accompany total joint arthroplasty, specifically infection. The degree to which patients seemed to undervalue the harms of infection (based on our knowledge and perception of those harms) suggests that surgeons need to take particular care in explaining the degree to which a prosthetic joint infection can harm or kill patients who develop one.

Peri-Prosthetic Joint Infection in Patients Prescribed Suppressive Antibiotic Therapy Undergoing Primary Total Joint Arthroplasty: A 1:4 Case Control Matched Study.

Background: Oral suppressive antibiotic therapy (SAT) has emerged as a potential means to increase rates of infection-free survival in many complex peri-prosthetic joint infection (PJI) cases after total joint arthroplasty (TJA). The purpose of the present study is to evaluate the risk of PJI of a new primary TJA in patients on oral SAT. Patients and Methods: A retrospective matched cohort study from five hospitals in a 20-year period within a large hospital network was performed. Inclusion criteria consisted of patients over age 18 undergoing primary TJA, with any order for oral long-term (>6 months duration) SAT, and minimum of one-year clinical follow-up. Patients were matched 1:4 on age, gender, body mass index (BMI), hip or knee surgery, diabetes mellitus, smoking status, and indication for primary TJA. Student t-test, Fisher exact, and χ2 tests were utilized for group comparisons. Our study was powered to detect a 10.5% increase in PJI incidence compared with a 1% baseline rate of PJI. Results: We identified 45 TJA in 33 patients receiving SAT, which were matched to 180 control cases. There was no difference in the rate of development of PJI at any time point within follow-up between the SAT cohort and control group (2.22% vs. 1.11%; p = 0.561). Conclusions: We found a 2.22% rate of PJI in a cohort of patients receiving SAT identified over a 20-year period. As the clinical scenario of primary TJA while on SAT is rare but likely to become more prevalent, future large-scale studies can be performed to better clarify rates and risk of PJI in this population.

One-Year Readmissions Following Total Joint Arthroplasty May Be Associated With Failure to Achieve the Minimal Clinically Important Difference of Patient-Reported Outcomes Measurement Information System Physical, Mental, and Physical-Short Form-10a.

The primary aims of our study were to determine if hospital readmissions within one year following primary total joint arthroplasty (TJA) and their relative timing influence patients' ability to achieve the two-year Patient-Reported Outcomes Measurement Information System (PROMIS) physical, PROMIS mental, and PROMIS Physical-Function-Short-Form-10a (SF-10a) minimal clinically important difference (MCID). This is a retrospective study conducted using data from a multi-institutional, arthroplasty registry. Only patients with paired patient-reported outcome measure (PROM) assessments (preoperatively and two years postoperatively) were included. Five separate readmission cohorts were formed: (1) any-cause readmission within one year, (2) any-cause readmission within 90 days, (3) non-index-surgery-related readmission within 90 days, (4) index-surgery-related readmission within one year, and (5) index-surgery-related readmission within 90 days. A propensity score match was used to match each of the patients to one of the 972 patients (1:1 basis) in the non-readmission group. The association between failure to achieve each of the three two-year MCIDs and Readmission status was analyzed using logistic regression. We found that all readmissions within one year and index-surgery-related readmissions within one year resulted in an increased risk of failure to achieve the two-year MCID across all three collected PROMs. Index surgery-related readmissions within 90 days (OR 3.24; 95% CI 1.05-11.05; p=0.048) sustained significantly different rates of two-year PROMIS physical MCID achievement compared to matched controls. Postoperative complications requiring readmission, particularly those related to the joint arthroplasty and those within 90 days of index surgery, significantly impact the ability to achieve the two-year MCID of PROMs.

The effect of the COVID-19 pandemic on revision total hip and knee arthroplasty at a large academic hospital network.

We sought to quantify the impact of COVID-19 on canceled revision total joint arthroplasty (TJA) in a large academic hospital network. We performed a retrospective analysis of revision TKA and THA in a healthcare system containing 5 hospitals in a time period of 8 months prior to and 8 months after the cessation of elective surgery. We found a 30.1% decrease in revision TKA and a 6.80% decrease in revision THA. Revision TJA volume decreased in our healthcare system during COVID-19 compared to prior to the pandemic, which will likely have lasting financial and clinical ramifications for the healthcare system.

Understanding Outcomes and the Ability to Return to Work After Rotator Cuff Repair in the Workers' Compensation Population.

Introduction Patients with a worker compensation claim are associated with a greater probability of continued symptoms and activity intolerance. This study aims to determine predictors of improved patient-reported outcomes in the workers' compensation population. Methods Patients with workers' compensation claims undergoing arthroscopic rotator cuff repair between 2010 and 2015 were included. Age, gender, dominant hand, occupation, and number of tendons involved were analyzed. At a minimum of two years, patients were contacted to complete American Shoulder and Elbow Surgeons (ASES) Survey, Simple Shoulder Test (SST), and return-to-work status (RTW). Preoperative characteristics and scores were then compared. Results Seventy patients were available for follow-up at an average of 5.4 years (range: 2.1-8.8 years). Average age was 55 years (range: 37-72); 55 (78.6%) were males, 23 (32.9%) were laborers; and 59 (84.2%) patients returned to work. The sole predictor for RTW was surgery on the non-dominant arm (96.5% versus 75.6%; p = 0.021). Laborers showed decreased RTW (p = 0.03). Patients who completed RTW had excellent outcomes with higher ASES (87 versus 50; p value < 0.001) and SST scores (10.4 versus 4.6; p < 0.001). Patients with three tendon tears had inferior ASES (p = 0.026) and SST (p = 0.023) scores than those with less. Conclusion Most workers' compensation patients have excellent outcomes from rotator cuff repair. Patients with three tendon tear repairs demonstrated the worst functional outcomes. Laborers showed decreased ability to RTW with nearly one-third unable.

Low Body Mass Index Is a Predictor for Mortality and Increased Length of Stay Following Total Joint Arthroplasty.

BACKGROUND: Malnutrition is a devastating condition which disproportionally affects the elderly population. Malnutrition furthers the pre-existing elevated risk for osteoarthritis in this population, thus exacerbating joint damage in patients and furthering the need for total joint arthroplasty (TJA). A marker for malnutrition is a low body mass index (BMI). The purpose of this study is to investigate whether low BMI status increased the risk for 2-year mortality or reoperation, 90-day readmission, or extended length of stay (LOS) following TJA. METHODS: A retrospective study was performed using the Partners Arthroplasty Registry which contains data from 2016 to 2019. The registry was queried for primary total hip and primary total knee arthroplasty (TKA) patients that had a minimum of 2-years follow-up data. Demographic, surgical, and clinical outcome variables were obtained from these patients. The association between underweight BMI and objective outcomes of reoperation, 90-day readmission, mortality, and LOS was evaluated by univariate analysis followed by multiple logistic and linear regression analyses. RESULTS: The final cohort used for analysis consisted of 4802 TJA cases. After accounting for potential confounders, underweight BMI was found to be independently associated with increased risk of mortality within 2 years following TJA (odds ratio 8.77) (95% confidence interval 2.14-32.0) and increased LOS of 0.44 days (95% confidence interval 0.02-0.86). CONCLUSION: Our findings demonstrate that TJA patients with an underweight BMI experience an 8 times increased risk of 2-year mortality and an increased LOS of 0.44 days. Orthopedic surgeons should consider nutritional consultation and medical optimization in these high-risk patients prior to surgery.

Patient-Reported Mental Health Score Influences Physical Function After Primary Total Knee Arthroplasty.

BACKGROUND: Despite the effectiveness of total knee arthroplasty (TKA), patients often have lingering pain and dysfunction. Recent studies have raised concerns that preoperative mental health may negatively affect outcomes after TKA. The primary aim of this study investigates the relationship between patient-reported mental health and postoperative physical function following TKA. METHODS: A retrospective study of 1392 primary TKA patients was performed. Mental health and physical function scores were measured using the Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health, and PROMIS Physical Function 10a and Knee injury and Osteoarthritis Outcome Score Physical Function (KOOS-PS) short forms. These assessments were completed preoperatively and up to 1-year postoperatively. Patients were stratified based on preoperative mental health scores into five distinct categories ranging from "Poor" to "Excellent." Locally estimated scatter plot smoothing curves (LOESS) were fit to the data examining physical function score trends over time. RESULTS: Patients with higher mental health scores before surgery demonstrated better preoperative and postoperative physical function scores. However, all patients experienced similar gains in physical function following surgery. Despite this early improvement, patients with the worst mental health scores experienced a sharp decline in physical function approximately a year after surgery and did not appear to recover. CONCLUSIONS: Poor mental health should not be a contraindication for performing TKA. For patients with the lowest mental health scores, physicians should account for the possibility that physical function scores may deteriorate a year after surgery. Tighter follow-up guidelines, more frequent physical therapy visits, or treatment for mental health issues may be considered to counter such deterioration.

Can Preoperative Factors Be Used to Determine Optimal Implant Design for Total Knee Arthroplasty?

INTRODUCTION: Although studies have demonstrated similar outcomes between ultracongruent (UC) and traditional bearings, debate exists regarding the optimum bearing surface. We sought to determine whether preoperative factors may predict use of a UC bearing when compared to a standard cruciate retaining (CR) group. MATERIALS AND METHODS: The study cohort consisted of 117 patients who underwent primary total knee arthroplasty (TKA). The implants utilized were either the CR or UC polyethylene components of the Zimmer Persona® Total Knee System. Patient demographics and comorbidities were documented. Intraoperative variables and postoperative outcomes were recorded. We calculated change in tibial slope and femoral condylar offset from pre- to post-surgery and computed the percentage of patients for whom an increase in tibial slope or femoral condylar offset was determined. All dependent variables were compared between patients who received the UC component and those with a CR component using either independent samples t-tests or chi-square test of independence. RESULTS: Thirty-nine patients received a UC insert and 78 patients received a CR insert. Mean length of stay (p=0.017), estimated blood loss (p=0.021), and tourniquet time (p=0.032) were greater for the UC group. Intraoperative implant variables were not different between the groups. However, the proportion of patients for whom tibial slope increased postoperatively was greater for the UC group compared to the CR group (p=0.018). CONCLUSION: Our results showed that no preoperative medical comorbidities or demographic factors predicted use of the UC bearing; however, postoperative tibial slope was increased for a greater number of patients who received the UC implant.

Morbid Obesity Is a Risk Factor for Infection Recurrence Following Debridement, Antibiotics, and Implant Retention for Periprosthetic Joint Infection.

BACKGROUND: Although morbid obesity is an established risk factor for periprosthetic joint infection following total hip arthroplasty and total knee arthroplasty, little is known regarding the infection control rate of this cohort following debridement, antibiotics, and implant retention (DAIR). The purpose of this study is to investigate the infection control rate following DAIR in a morbidly obese patient cohort compared to a nonobese patient cohort and discern the relationship between time from diagnosis to treatment and risk of DAIR failure. METHODS: Results of all DAIR procedures were retrospectively reviewed across 4 institutions. Those with a body mass index of at least 40 kg/m2 were matched 2:1 on the basis of patient age, sex, date of surgery, and presence of staphylococcal species in culture to a cohort of patients with body mass index of <30 kg/m2. Demographic variables were collected for each patient. Kaplan-Meier survivorship curves were constructed and multivariable Cox regression was performed for analysis. RESULTS: The morbidly obese group experienced a higher treatment failure rate (57.9%) compared to the nonobese group (36.8%; P = .035). Morbid obesity and major depressive disorder/generalized anxiety disorder diagnosis significantly increased the risk of failure, with hazard ratios of 1.82 and 2.09, respectively. Morbidly obese patients who received DAIR within 48 hours of symptom presentation did not face an increased risk of reinfection compared to nonobese patients. CONCLUSION: Our findings suggest morbidly obese patients face an increased risk of DAIR failure; however, this risk can be mitigated if DAIR is received within 48 hours of symptom onset.

Do All Rigid and Unbalanced Spines Present the Same Risk of Dislocation After Total Hip Arthroplasty? A Comparison Study Between Patients With Ankylosing Spondylitis and History of Spinal Fusion.

BACKGROUND: Spines with ankylosis or with a history of lumbosacral fusions have been collectively classified as rigid and unbalanced, and associated with an increased rate of dislocation after total hip arthroplasty (THA). It remains unknown whether the cause of spinal arthrodesis influences the dislocation rate. METHODS: A retrospective study was conducted from January 2000 to December 2017, with an institutional review board's approval to identify 2 cohorts with a history of THA: one with ankylosing spondylitis (AS) involving the lumbosacral spine and another cohort with a history of lumbosacral spinal fusion (SF). A chart review was performed to collect demographic and surgical variables. Lumbar lordosis angle (LLA), acetabular anteversion, and inclination angle measurements were taken for each patient. Kaplan-Meier survivorship curves were constructed and multivariable Cox regression was performed for analysis. RESULTS: The AS and SF cohorts consisted of 142 and 135 patients, respectively. The SF group had a greater mean LLA (34.18°) than the AS group (21°). A total of 16 patients (11.85%) suffered from dislocation after primary elective THA in the SF group, whereas 4 patients (2.82%) in the AS group. After multivariable Cox regression analysis, increasing LLA and hips outside of the Lewinnek safe zone were found to be associated with a higher hazard of dislocation after THA. CONCLUSION: We found that the degree of lumbar spine curvature is more associated with dislocation after THA than the history of SF itself; specifically, an increase in lumbar lordosis angle of 1º increases the probability of dislocation by 13% among AS and SF patients.

Staged vs Concurrent Hardware Removal During Conversion Total Knee Arthroplasty.

BACKGROUND: Conversion total knee arthroplasty (TKA) in the presence of periarticular hardware can be associated with increased resource utilization, complications, and revisions. However, little guidance exists on the optimal approach to hardware removal. The purpose of this study is to compare outcomes of conversion TKA with hardware removal performed in either a staged or concurrent manner. METHODS: This is a retrospective study of 155 TKA operations performed with staged (45) or concurrent (110) removal of hardware at the time of TKA. Differences in patient data, case data, complications, reoperations, and revisions were evaluated. Subgroup comparisons of cases involving major hardware (plates, nails, rods), minor hardware (screws, buttons, wires), and tibial plates were performed. RESULTS: There were no differences in age, sex, body mass index, or comorbidities between patients who underwent staged or concurrent hardware removal. Rates of complications, reoperations, and revisions did not differ at multiple time points (90 days, 1 year, 2 years, 4 years). Patients who underwent staged hardware removal were more likely to have had prior surgery for fracture reconstruction (68% vs 33%, P < .001), to have had major hardware removed (84% vs 59%, P = .03), and were less likely to have had hardware removal performed through a single incision with TKA (50% vs 92%, P < .001). Subgroup analysis of major and minor hardware cases demonstrated comparable outcomes. CONCLUSION: There remains no established benefit to either a staged or concurrent approach to hardware removal at the time of TKA. This is true regardless of hardware burden. At this time, a case-by-case approach should be taken to conversion TKA in the presence of periarticular hardware.

Dual Surgical Setup May Improve Infection Control Rate of Debridement and Implant Retention Procedures for Periprosthetic Infections of the Hip and Knee.

BACKGROUND: Debridement, antibiotics, and implant retention (DAIR) is an appealing treatment option for periprosthetic joint infection (PJI) due to its low cost and low morbidity. There are many nonmodifiable risk factors for DAIR failure that have previously been established. A dual DAIR setup constitutes establishing a new, sterile field after the initial debridement. The purpose of this study is to determine whether the modifiable surgical technique of a dual setup improves the infection control rate following PJI. METHODS: A retrospective study was conducted from January 1, 2000 to December 31, 2017 to identify patients who underwent a DAIR procedure as initial surgical treatment for PJI of the hip or knee. Patients were divided between 2 groups, failed and successful DAIR procedures. Failure was defined as infection recurrence requiring surgical intervention. Demographic (age, gender, body mass index, smoking status, American Society of Anesthesiologists status), preoperative comorbidity (hypertension, cardiac disease, diabetes status, depression or anxiety diagnosis, pulmonary disease), operating surgeon, single vs dual setup, hospital, use of long-term antibiotics postoperatively (greater than 6 weeks of intravenous antibiotics), joint, and laterality data were compared between cohorts using multivariate regression analysis. RESULTS: Two hundred sixty-three patients were identified who underwent DAIR as the exclusive and initial treatment for PJI. Single vs dual setup, knee vs hip joint, cardiac or vascular disease diagnosis, major depressive disorder or generalized anxiety disorder diagnosis, and staphylococcal infections were found to be independent predictive variables for DAIR failure. CONCLUSION: In our series, the dual setup DAIR was a modifiable surgical technique that significantly decreased the risk of infection recurrence compared to single setup DAIR.

Short-Term Clinical Outcomes of a Conical Prosthesis Used in Revision Total Hip Arthroplasty.

INTRODUCTION: Although primary total hip arthroplasty (THA) stem designs have evolved from conventional lengths to shorter lengths, revision stems have not undergone a similar change. Tapered, conical prostheses have performed well in primary THA, however their use in revision THA has not been thoroughly investigated. Our purpose was to report the short-term radiographic and clinical outcomes of the Wagner Cone Prosthesis® (Zimmer Biomet, Warsaw, Indiana) in revision THA. MATERIALS AND METHODS: An institutional review board approved retrospective study was performed to identify all revision THAs with minimum one-year clinical and radiographic follow up between January 1, 2007 and December 31, 2018, which used a short conical tapered stem to reconstruct the femur. Demographic, surgical, and radiographic variables were collected for each patient. RESULTS: Fifteen hips that fit inclusion criteria were identified. Implant survivorship was 93.3% with a mean follow up of 33.6 months. Radiographic analysis revealed mean subsidence of 2.57mm ± 4.31mm and a limb-length difference of 0.69mm ± 12.4mm longer than the contralateral side. Furthermore, pedestal sign was observed on preoperative radiographs of six patients, none of whom suffered periprosthetic fracture or femoral cortex perforation upon insertion of the conical prosthesis. CONCLUSION: Our findings suggest that the Wagner Cone Prosthesis® is as a useful implant for revision THA. In our sample, it had excellent survivorship, impressive postoperative radiographic measurements obtained from most recent follow up, minimal mean subsidence, and minimal complication rates. Further prospective studies with longer follow up are needed to determine the efficacy of this stem in revision THA.

Effect of prior ipsilateral lower extremity surgery on 2-year outcomes following hip arthroscopy for femoroacetabular impingement syndrome.

The purpose of this study was to determine the influence of prior lower extremity surgery on patient reported outcomes following hip arthroscopy for femoroacetabular impingement syndrome (FAIS). Consecutive patients who underwent hip arthroscopy for FAIS and a prior history of ipsilateral lower extremity surgery were identified and matched 2:1 by age, gender, and body mass index (BMI) to controls without a history of lower extremity surgery. The minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) were calculated for HOS-ADL, HOS-SS, and mHHS. Preoperative and 2-year postoperative patient reported outcomes of both groups were compared, and logistic regression was performed to determine whether lower extremity surgery influenced achieving MCID and PASS. A total of 102 patients (24.94%) with prior history of ipsilateral lower extremity surgery were identified. Ipsilateral orthopaedic knee surgery accounted for more than half (53.92%) of all prior surgeries. Patients with a history of ipsilateral lower extremity surgery had significant lower 2-year PROs, satisfaction, and greater pain when compared to patients without lower extremity surgery (P < 0.001 all). A history of ipsilateral lower extremity surgery was a negative predictor of achieving MCID for HOS-ADL and HOS-SS, as well as PASS for HOS-ADL, HOS-SS, and mHHS (P < 0.001 all). In conclusion, patients with prior lower extremity surgery were found to have inferior outcome scores and a lower likelihood of achieving clinically significant outcome improvement compared to patients without a history of lower extremity surgery at two years postoperatively.