Outcomes of Total Knee Arthroplasty Revisions in Obese and Morbidly Obese Patient Populations

BackgroundThe obese population is at higher risk for complications following primary total knee arthroplasty (TKA), but little data is available regarding revision outcomes. This study aimed to investigate the role of body mass index (BMI) in the cause for revision TKA and whether BMI classification is predictive of outcomes.MethodsA multi-institutional database was generated, including revision TKAs from 2012 to 2019. Data collection included demographics, comorbidities, surgery types (primary revision, repeat revision), reasons for revision, lengths of hospital stay, and surgical times. Patients were compared using 3 BMI categories: nonobese (18.5 to 29.9), obese (30 to 39.9), and morbidly obese (≥40). Categorical and continuous variables were analyzed using chi-square and 1-way analysis of variance tests, respectively. Regression analyses were used to compare reasons for revision among weight classes.ResultsObese and morbidly obese patients showed significant risk for repeat revision surgery in comparison to normal weight patients. Obese patients were at higher risk for primary revision due to stiffness/fibrosis and repeat revision due to malposition. In comparison to the obese population, morbidly obese patients were more likely to require primary revision for dislocation and implant loosening.ConclusionSignificant differences in primary and repeat revision etiologies exist among weight classes. Furthermore, obese and morbidly obese patients have a greater risk of requiring repeat revision surgery. These patients should be informed of their risk for multiple operations, and surgeons should be aware of the differences in revision etiologies when anticipating complications following primary TKA.     

Postoperative Complications of Total Joint Arthroplasty in Obese Patients Stratified by BMI

Background

High body mass index (BMI) is associated with significant complications in patients undergoing total joint arthroplasty. Many studies have evaluated this trend, but few have looked at the rates of complications based on BMI as a continuous variable. The purpose of this study was to stratify obese patients into 3 BMI categories and evaluate their rates of complications and gauge whether transitioning from higher to lower BMI category lowers complication.

Midterm Survivorship and Complications of Total Knee Arthroplasty in Patients With Dwarfism

Background

Dwarfism is associated with skeletal dysplasias and joint deformities that frequently result in osteoarthritis requiring treatment with total knee arthroplasty (TKA). These surgeries can be challenging because of alignment deformities, poor bone stock, and smaller components. This study aims to compare TKA implant survivorship and complications between dwarf and nondwarf patients.

Effect of Total Knee Arthroplasty on Metabolic Syndrome

The purpose of this study was to evaluate the effect of changing activity after total knee arthroplasty (TKA) on metabolic syndrome with a follow-up period of 2 years. Two hundred consecutive patients who were to undergo TKA were prospectively enrolled. The patients' blood pressure, fasting plasma glucose level, the lipid profile, the waist circumference, the Knee Society score, and the Lower Extremity Activity Scale were measured preoperatively and at the 2-year follow-up visit. The data from 169 patients were finally collected and reviewed. Two years after primary TKA, there was no change in the prevalence of metabolic syndrome, despite that the patients had a significant increase of their physical activity.     

The Impact of Metabolic Syndrome on 30-Day Complications Following Total Joint Arthroplasty

Background

The arthroplasty population increasingly presents with comorbid conditions linked to elevated risk of postsurgical complications. Current quality improvement initiatives require providers to more accurately assess and manage risk presurgically. In this investigation, we assess the effect of metabolic syndrome (MetS), as well as the effect of body mass index (BMI) within MetS, on the risk of complication following hip and knee arthroplasty.

Primary Total Knee Arthroplasty After Solid Organ Transplant: Survivorship and Complications

Background

Clinical outcomes remain largely unknown beyond perioperative and short-term follow-up of solid organ transplant (SOT) patients undergoing total knee arthroplasty (TKA).

All-Cause In-Hospital Complications and Urinary Tract Infections Increased in Obese Patients Undergoing Total Knee Arthroplasty

The aims of this study were to determine the rates of in-hospital complications, discharge disposition, and length of stay for patients with varying degrees of obesity. We identified 4718 patients who underwent TKA between 2007 and 2010. After adjusting for age, sex, race, education, Deyo–Charlson comorbidity index, insurance, and discharge disposition, obese patients were more likely to develop any in-hospital complication (6.4% vs. 4.8%, respectively; P = 0.0097; OR = 1.5). When analyzing specific in-hospital complications, obese patients were more likely to suffer urinary tract infections (P = 0.0029). They were also more likely to be discharged to a rehabilitation facility (P = 0.001). There was no significant difference in other postoperative complications. In summary, obese patients undergoing primary TKA are at increased risk for all-cause in-hospital complications and urinary tract infections and are more likely to be discharged to a rehabilitation facility.     

Prior Knee Arthroscopy Does Not Influence Long-Term Total Knee Arthroplasty Outcomes and Survivorship

Background

Arthroscopic knee surgery frequently precedes total knee arthroplasty (TKA). There have been mixed data on the effect of prior arthroscopic surgery on results of TKA. The purpose of this study was to compare the 10-year Knee Society Score (KSS), survivorship, and complications of TKA in a cohort of patients who had a previous knee arthroscopy to a control cohort.

Association Between Body Mass Index and Thirty-Day Complications After Total Knee Arthroplasty

Background

Although previous studies have evaluated the effect of obesity on the outcomes of total knee arthroplasty (TKA), most considered obesity as a binary variable. It is important to compare different weight categories and consider body mass index (BMI) as a continuous variable to understand the effects of obesity across the entire range of BMI. Therefore, the objective of this study is to analyze the effect of BMI on 30-day readmissions and complications after TKA, considering BMI as both a categorical and a continuous variable.

Primary and Revision Total Knee Arthroplasty in Patients With Pulmonary Hypertension: High Perioperative Mortality and Complications

BackgroundAlthough perioperative medical management during total knee arthroplasty (TKA) has improved, there is limited literature characterizing outcomes of patients with pulmonary hypertension (HTN). This study examined mortality, medical complications, implant survivorship, and clinical outcomes in this medically complex cohort.MethodsWe identified 887 patients with pulmonary HTN who underwent 881 primary TKAs and 228 revision TKAs from 2000 to 2016 at a tertiary care center. Patients were followed up at regular intervals until death, revision surgery, or last clinical follow-up. Perioperative medical complications were individually reviewed. The risk of death was examined by calculating standardized mortality ratios and Cox proportional hazards regression models. Cumulative incidence analysis was used for reporting mortality, revision, and reoperation with death as a competing risk.ResultsThe 90-day mortality was 0.7% and 4.8% for primary and revision TKAs, respectively. The risk of death was 2-fold higher compared to primary (hazard ratio 2.54, 95% confidence interval [CI] 2.12-3.05) and revision (hazard ratio 2.16, 95% CI 1.78-2.62) TKA patients without pulmonary HTN. Rate of medical complications within 90 days from surgery was 6.5% and 14% in primary and revision TKAs. The 10-year cumulative incidence of any revision was 5% and 16% in primaries and revisions, respectively.ConclusionPatients with pulmonary HTN undergoing primary and revision TKAs had excess risk of death and experience a high rate of medical complications within 90 days of surgery. Counseling of risks, medical optimization, and referral to tertiary centers should be considered.Level of EvidenceLevel IV.     

Impact of Metabolic Syndrome on Perioperative Complication Rates After Total Joint Arthroplasty Surgery

This study investigated the impact of metabolic syndrome (MetS) on perioperative and postoperative complication rates: the results of a cohort of 168 total hip and knee arthroplasties, 63 of normal weight, 105 with obesity without risk factors for metabolic syndrome and 39 with obesity and other factors that classify them with metabolic syndrome. Patients with metabolic syndrome were more likely to have complications than those without metabolic syndrome (P = 0.0156). Perioperative and postoperative complication rates for the MetS and control groups were 35.9% and 16.3%, respectively. Elevated BMI was the element of MetS that had the largest impact on post-surgical complication rates, and this was statistically significant (P = 0.0028). The presence of MetS in patients undergoing total joint arthroplasty has a significant impact on surgical complication rates. This cannot be attributed to the BMI component alone, and may help guide efforts of patient optimization prior to total joint arthroplasty.     

Outcomes of Primary Total Knee Arthroplasty in Patients With Ehlers-Danlos Syndromes

Background

Ehlers-Danlos syndromes (EDS) are connective tissue disorders that cause defects in collagen synthesis or processing, resulting in joint hypermobility. Following total knee arthroplasty (TKA), concern exists that hypermobility will affect the outcome as prosthesis relies on soft tissues for stability. The purpose of this study is to investigate the outcome of TKA in the setting of EDS compared to patients undergoing TKA for osteoarthritis (OA).

Patients With Uncontrolled Components of Metabolic Syndrome Have Increased Risk of Complications Following Total Joint Arthroplasty

Metabolic syndrome (MetS)–a diagnostic grouping of diabetes, dyslipidemia, hypertension, and obesity–has been indicated as a risk factor for perioperative complications following total joint arthroplasty (TJA). This study investigates the impact of MetS on perioperative complications, specifically the importance of controlling MetS components. One hundred thirty-three patients undergoing TJA with all four components of MetS were identified. They were matched one-to-one with patients without MetS. Control of diabetes, dyslipidemia, and hypertension was assessed. Thirty-five patients with MetS were found to have at least a single uncontrolled component. The complication rates were 49%, 8%, and 8% for uncontrolled MetS, controlled MetS, and no MetS, respectively. Multivariate analysis confirmed independent associations between control of MetS components and both perioperative complications and length of stay. Both surgeons and patients should be aware of the substantial risk of dangerous complications following TJA in patients with uncontrolled metabolic syndrome.     

Survivorship and Outcomes in Patients With Multiple Sclerosis Undergoing Total Joint Arthroplasty

Background

Patients with multiple sclerosis (MS) frequently require total joint arthroplasty (TJA). The outcomes of TJA in patients with MS, who are frequently on immunomodulatory medications and physically deconditioned, remain largely unknown. The aim of this study is to elucidate the survivorship and reasons for failure in this patient population.

A One-Question Patient-Reported Outcome Measure Is Comparable to Multiple-Question Measures in Total Knee Arthroplasty Patients

BackgroundPatient-reported outcome measures (PROMs) are important for tracking outcomes following total knee arthroplasty (TKA) but can be limited by time constraints and patient compliance. We sought to evaluate the utility of the one-question, modified single assessment numerical evaluation (M-SANE) score in TKA patients compared to legacy PROMs.MethodsPatients undergoing TKA completed the Patient-Reported Outcomes Measurement Information System-10 (PROMIS-10), the Knee Disability and Osteoarthritis Outcomes Score Junior (KOOS Jr), and M-SANE (modified-SANE) assessments both preoperatively and postoperatively. The M-SANE score asked patients to rate their native or prosthetic knee on a scale from 0 to 10, with 10 being the best function. M-SANE validity was determined by the Spearman’s correlation between the collected PROMs and the Bland-Altman plots. PROM responsiveness was assessed using the standardized response mean.ResultsIn total, 217 patients completed PROMs preoperatively and at 1 year postoperatively. Floor and ceiling effects of the M-SANE were higher than other PROMs but still relatively low (4%-11%). There was a moderate to strong correlation at nearly all time points between the M-SANE and KOOS Jr (ρ = 0.44-0.78, P < .001). There was a weak correlation between the M-SANE and PROMIS physical component summary at the preoperative evaluation (ρ = 0.28) but a strong correlation at 1-year follow up (0.65, P < .001). The long-term responsiveness of the M-SANE to TKA (standardized response mean [SRM] = 0.98, 95% confidence interval [CI] 0.80-1.17) was comparable to both the KOOS Jr (SRM = 1.19, 95% CI 1.00-1.38) and PROMIS physical component summary (SRM = 0.82, 95% CI 0.74-0.91). Bland-Altman plots demonstrated that the M-SANE and KOOS Jr capture combined knee pain and functionality differently.ConclusionThe M-SANE score was comparable to validated multiple-question PROMs in TKA patients. The demonstrated validity of the M-SANE, as well as its comparable responsiveness to more lengthy PROMs, highlights its use as a one-question PROM for assessment of patient undergoing TKA.     

Relationship Between Knee Anthropometry and Surgical Time in Total Knee Arthroplasty in Severely and Morbidly Obese Patients: A New Prognostic Index of Surgical Difficulty

BACKGROUND: Total knee arthroplasty (TKA) in patients with severe and morbid obesity is one of the current challenges in prosthetic knee surgery. The body mass index (BMI) is used to identify patients who may present difficulties during surgery and postoperative complications. We carried out a prospective study with an initial hypothesis that BMI is not associated with tourniquet time in obese patients undergoing TKA and that some anthropometric parameters may be useful in predicting tourniquet time in severely and morbidly obese patients. METHODS: One hundred consecutive patients diagnosed with knee osteoarthritis with BMI > or =35 kg/m(2) scheduled for TKA were prospectively studied. Suprapatellar, infrapatellar, and supra/infrapatellar anthropometric indexes were calculated before surgery. The tourniquet time was determined. RESULTS: The mean BMI was 39.81 kg/m(2) (SD +/- 3.75). A total of 58% of patients were classified as class III obesity (BMI 35-39.99) and 42% as class IV (BMI > or = 40) Mean tourniquet time was 41.67 min (SD +/- 9.26). There was no association between the BMI and tourniquet time. The suprapatellar index was negatively associated with tourniquet time (p < 0.038). DISCUSSION: The BMI is not the only parameter that should be considered in order to identify severely and morbidly obese patients who may have more surgical difficulties during TKA. Preoperative determination of the suprapatellar index helped us to classify these patients according to the morphology of the knee and predicted a longer tourniquet time and, therefore, greater surgical difficulty, in patients with a suprapatellar ratio below 1.6 in this study.     

The Impact of Metabolic Syndrome on Reoperations and Complications After Primary Total Hip Arthroplasty

BackgroundMetabolic syndrome (MetS) represents a constellation of interrelated conditions including insulin resistance, abdominal obesity, hypertension, and dyslipidemia. The goals of this study are to determine the impact of MetS on implant survivorship, complications, and clinical outcomes after primary total hip arthroplasty (THA).MethodsUtilizing our institutional total joint registry, 1,268 patients undergoing primary THA were identified with MetS based on the World Health Organization definition and matched 1:1 to those without MetS based on age, gender, and surgical year. MetS patients were further stratified according to the World Health Organization body mass index (BMI) classification to contextualize obesity. Kaplan-Meier analyses were utilized to compare survivorship free of any reoperation, revision, and complications. Clinical outcomes were assessed with Harris hip scores. Mean follow-up after THA was 5 years.ResultsMetS patients had significantly worse 5-year survivorship free from any reoperation compared to those without MetS (93.5% vs 96.1%, respectively; hazard ratio [HR] 1.4, P = .04). When stratifying MetS and BMI classification, the BMI >40 kg/m² had significantly decreased 5-year implant survivorship free from any reoperation (85.9% vs 96.1%, HR 3.4, P < .001), any revision (91.7% vs 97.3%, HR 2.7, P < .001), and reoperation for periprosthetic joint infection (95% vs 99%, HR 5.1, P < .001). Both groups experienced significant and similar improvement in final Harris hip scores (P < .001).ConclusionPatients with MetS had a 1.4-fold increased risk of reoperation after primary THA compared to a matched cohort without the condition. MetS patients with a BMI >40 kg/m² had the highest risk of reoperation, and had a significantly higher revision and periprosthetic joint infection rates, suggesting that morbid obesity remains a critical, independent risk factor beyond MetS.Level of EvidenceLevel 3, Case-control study.     

Overweight and Obese Patients Require Total Hip and Total Knee Arthroplasty at a Younger Age

Osteoarthritis (OA) of the hip and knee is associated with obesity but the exact effect remains unknown. The aim of this study was to investigate the independent association between the age at which total hip (THA) and knee arthroplasty (TKA) are required for end-stage severe OA according to body mass index (BMI) category. A retrospective study of 3,699 patients undergoing primary THR and 4,740 patients undergoing a primary TKA for the treatment of end-stage OA. Patient demographics, BMI, comorbidity, social deprivation, Short form 12 and Western Ontario and McMaster Universities OA Index score pre-operatively were collected. Linear regression analysis identified that there was an earlier age at which THA and TKA were performed with increasing obesity BMI category compared with normal-weight patients when adjusting for confounding variables. Using the normal weight category as the reference group overweight (0.9 years [95% confidence interval, CI] 0.0–1.8) and obese patients in class 1 (3.1 years, 95% CI 2.1–4.2), 2 (5.2 years, 95% CI 3.7–6.7), and 3 (7.4 years, 95% CI 5.0–9.8) required their THA at a significantly (p ≤ 0.04) earlier age. Again, using normal weight category as the reference group overweight (2.1 years, 95% CI 1.3–2.9) and obese patients in class 1 (4.7 years, 95% CI 3.8–5.6), 2 (6.7 years, 95% CI 5.6– 7.7) and 3 (10.5 years, 95% CI 8.9–12.1) required their TKA at a significantly (p < 0.001) earlier age. Overweight and obese patients required their THA and TKA at a significantly younger age. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:348-355, 2020     

Alcohol Withdrawal Is Associated With Worse Outcomes in Patients Undergoing Primary Total Knee or Total Hip Arthroplasty

BackgroundAlcohol withdrawal (AW) syndrome is an independent risk factor for postoperative complications. This study aims to evaluate the influence of AW on perioperative outcomes in patients who underwent primary total knee (TKA) or total hip arthroplasty (THA).MethodsWe used the National Inpatient Sample database to identify patients undergoing TKA/THA from 2003 to 2014. The primary exposure of interest was AW. Multivariable adjusted models were used to evaluate the association of AW with in-hospital medical complications, surgical complications, mortality, cost, and length of stay (LOS) in patients undergoing TKA/THA.ResultsThere were 2,971,539 adult hospitalizations for THAs and 6,367,713 hospitalizations for TKAs included in the present study, among which 0.14% of AW for THA patients and 0.10% of AW for TKA patients. Multivariable adjustment analysis suggested that AW was associated with an increased risk of medical complications (odds ratio [OR] 2.08, 95% confidence interval [CI] 1.79-2.42, P < .0001), surgical complications (OR 1.75, 95% CI 1.51-2.03, P < .0001), and had 4.79 times increase of in-hospital mortality, 26% increase of total cost, and 53% increase of LOS in THA procedures. For TKA procedures, AW was also associated with increased risk of medical complications (OR 3.14, 95% CI 2.78-3.56, P < .0001), surgical complications (OR 2.07, 95% CI 1.82-2.34, P < .0001) and 4.24 times increase of in-hospital mortality, 29% increase of total cost, and 58% increase of LOS after multivariable adjustment.ConclusionAW is associated with increased risk of in-hospital mortality, medical and surgical complications. Proactive surveillance and management of AW may be important in improving outcomes in patients who underwent THA and TKA procedure.     

Effect of Type 2 Diabetes on In-Hospital Postoperative Complications and Mortality After Primary Total Hip and Knee Arthroplasty

Background

We aimed to compare in-hospital postoperative complications (IHPC) and in-hospital mortality between patients with and without type 2 diabetes mellitus (T2DM) undergoing primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).