Lingering Risk: Bariatric Surgery Before Total Knee Arthroplasty

Effect of Prior Bariatric Surgery on the Outcomes of Joint Arthroplasty: A Systematic Review and Meta-Analysis

OBJECTIVE

Obesity is a risk factor for joint arthroplasty complications. With this systematic review and meta-analysis, we assessed whether a positive history of bariatric surgery influences postoperative outcomes in patients undergoing various types of joint arthroplasty.

METHODS

We conducted a comprehensive search database such as Scopus, PubMed, Medline Ovid, CNKI, and CENTRAL for studies comparing outcomes between patients undergoing arthroplasty with and without a history of bariatric surgery. We extracted data on short-term medical complications, venous thromboembolism (VTE), periprosthetic infections, superficial wound infections, hospital stay length, and operative time. We used the data to conduct meta-analyses using random-effects models and subgroup analyses based on the type of arthroplasty.

RESULTS

Overall, 15 studies with nearly 150,000 participants were included. The analysis showed that prior bariatric surgery did not significantly affect overall medical complications post-arthroplasty, with OR of 0.968 (95%CI, 0.706-1.327). For VTE, the results similarly indicated no substantial difference, with an OR of 0.912 (95%CI, 0.644-1.291). In assessing periprosthetic infections, the OR was 0.754 (95%CI, 0.535-1.064), showing comparable rates between patients with and without a history of bariatric surgery.Regarding superficial wound infections, the analysis produced an OR of 2.390 (95%CI, 0.723-7.897), indicating variability but not statistical significance. Hospital stay length was reduced in patients with a history of bariatric surgery, reflected by SMD of -0.113 (95%CI, -0.221 to -0.005). Lastly, operative time also showed a significant reduction, with an SMD of -0.462 (95%CI, -0.865 to -0.059).

CONCLUSIONS

Prior bariatric surgery does not reduce the risk of short-term complications post-arthroplasty, but it seems to reduce the hospital stay length and operative time. The effects vary significantly across different types of joint arthroplasty, suggesting a need for tailored preoperative assessments and care protocols.

PROTOCOL REGISTRATION

This systematic review and meta-analysis was registered at PROSPERO, with the number: CRD42024539052.

Association between bariatric surgery and outcomes of total joint arthroplasty: a meta-analysis

BACKGROUND

Total joint arthroplasty (TJA) alongside bariatric surgery (BS) is frequently operated on in obese arthritis patients. The controversy persists regarding BS before TJA, and the extent of its impact on the prognosis of TJA patients remains uncertain. To explore this, we conducted a meta-analysis.

METHODS

As of 1 October 2023, the latest search on PubMed, Cochrane Library, Embase, and Web of Science was conducted to compare outcomes between patients who underwent preoperative BS and those who did not. The analysis focused on parameters such as length of stay (LOS), infection risk, venous thromboembolism, revision, transfusions, dislocations, periprosthetic fractures, knee stiffness, medical complications, and all-cause mortality in the eligible studies.

RESULTS

This meta-analysis included 18 trials with a total of 292 196 patients. Pooled findings indicated that preoperative BS significantly shortened the LOS (MD, -0.16; 95% CI, -0.25 to 0.07; I2 =58%; P =0.0004) and increased the risk of dislocation within 90 days (OR, 1.70; 95% CI, 1.20- 2 .42; I2 =21%; P =0.003) and all-cause mortality within 30 days (OR, 3.69; 95% CI, 1.81-7.49; I2 = 0%; P  =0.0003) for TJA, in comparison with patients without BS. In the total hip arthroplasty (THA) subgroup, BS was more favorable, exhibiting significantly reduced risk of short-term revision (OR, 0.77; 95% C I , 0.61-0.99; I2 =0%; P =0.04) and long-term infection (OR, 0.72; 95% CI, 0.61-0.85; I2 =0%; P ≤0.0001). For total knee arthroplasty (TKA) patients, no significant benefit was identified. In addition, there was no statistically significant correlation between preoperative or postoperative BS and the occurrence of complications in TJA patients.

CONCLUSIONS AND RELEVANCE

Compared with the control group without BS, preoperative BS can shorten the LOS, increase the risk of dislocation within 90 days and all-cause mortality within 30 days in TJA, and reduce the risk of specific surgical complications in the THA subgroup but shows no significant difference in the TKA subgroup. There are no differences in clinical outcomes whether BS is performed before or after TJA. More high-quality trials are needed to further clarify the impact of BS on obese patients undergoing TJA.

Effect of bariatric surgery on postoperative outcomes of total hip arthroplasty: An updated systematic review and meta-analysis

Bariatric surgery may cause complications following total hip arthroplasty (THA); however, the evidence remains unclear. This review aims to evaluate the effects of bariatric surgery on THA complications. A systematic search of PubMed, EMBASE, Scopus, and Cochrane databases was performed. The eligibility criteria were cohort studies comparing THA patients with and without prior bariatric surgery. The primary outcomes were complications, length of hospital stay, readmission rate, and cost. The study quality was assessed using the MINORS criteria. The meta-analysis was performed using Review Manager 5.4. Nine cohort studies (170,882 patients) met our inclusion criteria. Bariatric surgery was not associated with the risk of dislocation at 90 days (OR 1.50, 95%CI 0.83, 2.70). However, at one-year follow-up, the dislocation rate was significantly lower in the NBS group (OR 1.51, 95%CI 1.23, 1.86). Bariatric surgery reduced the risk of periprosthetic fracture risk (OR 0.56, 95%CI, 0.33 to 0.96) but had no effect on infection (RR 0.96, 95%CI 0.76 to 1.20), revision rates (OR 1.07, 95%CI 0.89 to 1.29), or survival (HR 2.41, 95%CI 0.78 to 7.42). Hospital stay was lower in the bariatric group (-0.16 days, 95%CI -0.23 to -0.09) as were 30-day readmissions (OR 0.17, 95%CI 0.07 to 0.40). The total costs showed no significant differences between the groups (MD 2323.06, 95%CI -3274.80 - 7920.93). Bariatric surgery may reduce the risk of periprosthetic fractures and decrease the length of hospital stay and 30-day readmission after THA. However, it did not significantly impact overall complications, including infection or revision rates.

Scientific Evidence for the Updated Guidelines on Indications for Metabolic and Bariatric Surgery (IFSO/ASMBS)

The 2022 American Society of Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) updated the indications for Metabolic and Bariatric Surgery (MBS), replacing the previous guidelines established by the NIH over 30 years ago. The evidence supporting these updated guidelines has been strengthened to assist metabolic and bariatric surgeons, nutritionists, and other members of multidisciplinary teams, as well as patients. This study aims to assess the level of evidence and the strength of recommendations compared to the previously published criteria.

Total Knee Arthroplasty With or Without Prior Bariatric Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Studies comparing the outcomes of bariatric surgery followed by total knee arthroplasty (TKA) versus TKA alone in obese patients have disparate results. This systematic review and meta-analysis sought to compare TKA with and without prior bariatric surgery in obese patients.

METHODS

MEDLINE, PubMed, and Embase were searched from inception to April 9, 2023. There were twelve included studies that yielded 2,876,547 patients, of whom 62,818 and 2,813,729 underwent TKA with and without prior bariatric surgery, respectively. Primary outcomes were medical complications (ie, urinary tract infection, pneumonia, renal failure, respiratory failure, venous thromboembolism [VTE], arrhythmia, myocardial infarction, and stroke); surgical complications (ie, wound complications [eg, infection, hematoma, dehiscence, delayed wound healing, and seroma], periprosthetic joint infection, mechanical complications, periprosthetic fracture, knee stiffness, and failed hardware); revision, and mortality. Secondary outcomes were blood transfusion, length of stay (day), and readmission.

RESULTS

The odds ratios (OR) of 90-day VTE (OR = 0.75 [0.66, 0.85], P < .00001), 90-day stroke (OR = 0.58 [0.41, 0.81], P = .002), and 1-year periprosthetic fracture (OR = 0.74 [0.55, 0.99], P = .04) were lower in those who underwent bariatric surgery before TKA. Although the mean difference in hospital stays (-0.19 days [-0.23, -0.15], P < .00001) was statistically less in those who underwent bariatric surgery before TKA, it was not clinically relevant. The other outcomes were similar between the groups.

CONCLUSIONS

Bariatric surgery before TKA is beneficial in terms of a lower risk of VTE, stroke, and periprosthetic fracture. This analysis suggests surgeons consider discussing bariatric surgery before TKA in obese patients, especially those who are at risk of VTE and stroke.

Scientific evidence for the updated guidelines on indications for metabolic and bariatric surgery (IFSO/ASMBS)

The 2022 American Society for Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) updated the indications for metabolic and bariatric surgery (MBS), replacing the previous guidelines established by the National Institutes of Health (NIH) over 30 years ago. The evidence supporting these updated guidelines has been strengthened to assist metabolic and bariatric surgeons, nutritionists, and other members of multidisciplinary teams (MDTs), as well as patients. This study aims to assess the level of evidence and the strength of recommendations compared to the previously published criteria.

Is Preoperative Weight Reduction in Patients Who Have Body Mass Index ≥ 40 Associated With Lower Complication Rates After Primary Total Hip Arthroplasty?

BACKGROUND

Given the heightened risk of postoperative complications associated with obesity, delaying total hip arthroplasty (THA) in patients who have a body mass index (BMI) > 40 to maximize preoperative weight loss has been advocated by professional societies and orthopaedic surgeons. While the benefits of this strategy are not well-understood, previous studies have suggested that a 5% reduction in weight or BMI may be associated with reduced complications after THA.

METHODS

We identified 613 patients who underwent primary THA in a single institution during a 7-year period and who had a BMI >40 recorded from 9 to 12 months prior to surgery. Subjects were stratified into 3 cohorts based on whether their baseline BMI decreased by >5% (147 patients, 24%), was unchanged ( ± 5%) (336 patients, 55%), or increased by >5% (130 patients, 21%) on the day of surgery. The frequency of 90-days Hip Society and Centers for Medicare & Medicaid Services complications was compared between these cohorts. There were significant baseline differences between the cohorts with respect to baseline American Society of Anesthesiologists class (P < .001) and hemoglobin A1C (P = .011), which were accounted for in a multivariate regression analysis.

RESULTS

In univariate analysis, there was a lower incidence of readmission (P = .025) and total complications (P = .005) in the increased BMI cohort. The overall complication rate was 18.4% in the decreased BMI cohort, 17.6% in the unchanged cohort, and 6.2% in the increased cohort. However, multivariable regression analysis controlling for potential confounders did not find that preoperative change in BMI was associated with differences in 90-days complications between cohorts (P > .05).

CONCLUSIONS

Patients who have a BMI >40 and achieved a clinically significant (>5%) BMI reduction prior to THA did not have a lower risk of 90-days complications or readmissions. Thus, delaying THA in these patients to encourage weight loss may result in restricting access to a beneficial surgery without an appreciable safety benefit.

Timing Matters: Optimizing the Timeframe for Preoperative Weight Loss to Mitigate Postoperative Infection Risks in Total Knee Arthroplasty

BACKGROUND

We explore the incidence of periprosthetic infections post-total knee arthroplasty (TKA) in morbidly obese patients who achieved weight loss. Current American Academy of Orthopaedic Surgeons guidelines suggest a preoperative body mass index (BMI) below 40 for TKA. This study assesses infection risks in patients initially who had a BMI of 40-50 who reduced their BMI to under 35 at varying intervals prior to surgery.

METHODS

We reviewed a national, all-payer database, PearlDiver, for patients undergoing primary TKA. Patients were stratified based on initial BMI of 40 to 50 and reduction of BMI to less than 35 at 3 months (n = 1,932), 3 to 6 months (n = 794), 6 to 9 months (n = 2,233), and 9 to 12 months (n = 1,194) prior to TKA, as well as patients who had a BMI between 40 to 50 (n = 41,632) on the day of surgery. The nonobese group comprised of patients who had a BMI between 20 and 30 (n = 33,294). Multivariate analyses were performed at one-year follow-up.

RESULTS

We found an increased risk of PJI for patients who had achieved BMI reduction less than nine months prior to TKA, compared to the BMI 20 to 30 cohort at the one-year follow-up (P < .001). Patients who achieved BMI reduction nine to twelve months prior to TKA showed no significant difference in PJI risk compared to the matching nonobese cohort at one-year follow-up (P = .400).

CONCLUSIONS

In conclusion, our results suggest that weight loss should be achieved at least nine months before TKA to decrease infection risks. These findings have significant implications for surgical considerations in obese patients undergoing TKA.

Risk of revision total knee arthroplasty for patients with prior bariatric surgery or class III obesity

BACKGROUND

Bariatric surgery (BS) is indicated for select class III obesity patients undergoing total knee arthroplasty (TKA) to reduce obesity-related complications. This study assessed the effect of BS on TKA revision rates compared to the general population and class III obesity patients without a history of BS.

METHODS

A national database identified patients who had primary TKA. They were divided into two groups: those with BS prior to TKA and those without. Patients without BS formed two control groups, a matched general population, and a matched class III obese cohort. The BS group was matched with controls based on age, Charlson Comorbidity Index (CCI), gender, and diabetes mellitus. Revision rates were analyzed using Kaplan-Meier survival analysis and hazard ratios (HR), calculated using Cox proportional hazard modeling.

RESULTS

14,292 BS patients were compared to 57,006 matched general population controls, and 19,504 BS patients were compared to 77,846 matched class III obesity control patients. BS patients had a higher risk of 5-year all-cause revision (HR: 1.13; P = 0.014) and revision due to periprosthetic fracture (HR: 1.39; P < 0.001) compared to the general population. Compared to class III obesity controls, BS patients had a lower risk of 5-year revision due to prosthetic joint infection (HR: 0.77; P = 0.001), with no difference in all-cause revision (P = 0.362).

CONCLUSION

BS does not reduce all-cause TKA revision risk compared to the general or matched class III obesity population. However, it lowers the risk of revision due to prosthetic joint infection when compared to patients with class III obesity.

LEVEL OF EVIDENCE

IV.

Bariatric surgery prior to total hip arthroplasty: does timing or type matter?

INTRODUCTION

Morbid obesity is a known risk-factor for increased complications following total hip arthroplasty (THA). Thus, many orthopaedic surgeons recommend bariatric surgery (BS). However, there is no consensus on the type (commonly either a Roux-en-Y gastric bypass [RYGB] or sleeve gastrectomy [SG]) and timing of BS prior to THA. Therefore, the purpose of this study is to compare BS recipients prior to THA to assess differences in 90-day to 2-year medical/surgical complications as well as revisions for: (1) type of BS (RYGB and SG); and (2) timing of BS. Additionally, we aim to assess risk factors for postoperative prosthetic joint infections (PJIs), dislocations, and revisions.

METHODS

We queried a national, all-payer database to identify patients undergoing primary THA from January 2010 to October 2020 (n = 715,100). Patients were then divided into 6 cohorts: 2 cohorts without history of BS (body mass index [BMI] kg/m2 20-35 [n = 59,995]) and BMI > 40 [n = 36,799]); 2 cohorts with previous RYGB (n = 1278) or SG (n = 1051); and 2 cohorts that underwent BS either 6-12 months (n = 412) and >12 months (n = 1655) prior to the THA. Bivariate chi-square analyses of medical and surgical outcomes at 90 days-2 years were conducted. Multivariate logistic regressions identified independent risk factors for PJIs, dislocations, and revisions.

RESULTS

At 90 days-2 years, no differences in postoperative medical/surgical complications or revisions were seen among timing or type of BS. The BMI > 40 kg/m2 cohort had the highest complication profile among all other cohorts. Timing and type of BS has similar odds of PJIs, dislocations, and revisions.

CONCLUSIONS

Patients undergoing RYGB or SG 6-12 months and >1 year prior to THA showed similar complications profiles. These results suggest, bariatric patients do not need to wait 1 year before undergoing a THA.

Cost-Effectiveness of Weight-Loss Interventions Prior to Total Knee Replacement for Patients With Class III Obesity

OBJECTIVE

Class III obesity (body mass index >40 kg/m2 ) is associated with higher complications following total knee replacement (TKR), and weight loss is recommended. We aimed to establish the cost-effectiveness of Roux-en-Y gastric bypass (RYGB), laparoscopic sleeve gastrectomy (LSG), and lifestyle nonsurgical weight loss (LNSWL) interventions in knee osteoarthritis patients with class III obesity considering TKR.

METHODS

Using the Osteoarthritis Policy model and data from published literature to derive model inputs for RYGB, LSG, LNSWL, and TKR, we assessed the long-term clinical benefits, costs, and cost-effectiveness of weight-loss interventions for patients with class III obesity considering TKR. We assessed the following strategies with a health care sector perspective: 1) no weight loss/no TKR, 2) immediate TKR, 3) LNSWL, 4) LSG, and 5) RYGB. Each weight-loss strategy was followed by annual TKR reevaluation. Primary outcomes were cost, quality-adjusted life expectancy (QALE), and incremental cost-effectiveness ratios (ICERs), discounted at 3% per year. We conducted deterministic and probabilistic sensitivity analyses to examine the robustness of conclusions to input uncertainty.

RESULTS

LSG increased QALE by 1.64 quality-adjusted life-years (QALYs) and lifetime medical costs by $17,347 compared to no intervention, leading to an ICER of $10,600/QALY. RYGB increased QALE by 0.22 and costs by $4,607 beyond LSG, resulting in an ICER of $20,500/QALY. Relative to immediate TKR, LSG and RYGB delayed and decreased TKR utilization. In the probabilistic sensitivity analysis, RYGB was cost-effective in 67% of iterations at a willingness-to-pay threshold of $50,000/QALY.

CONCLUSION

For patients with class III obesity considering TKR, RYGB provides good value while immediate TKR without weight loss is not economically efficient.

Does Value-Based Care Threaten Joint Arthroplasty Access for Vulnerable Patient Populations?: AOA Critical Issues

Health-care expenses have been projected to increase from 17.7% of the U.S. gross domestic product (GDP) in 2014 to 19.6% in 2024. The unsustainable increase in health-care costs has contributed toward support for value-based health care (VBHC) reform. Contemporary VBHC reform programs relevant to orthopaedic surgery include the voluntary Bundled Payments for Care Improvement initiatives (BPCI and BPCI-Advanced) and the Comprehensive Care for Joint Replacement (CJR) program, a mandatory bundled payment program.The purported benefits of transitioning from volume-based reimbursement to value-based reimbursement include moving from a fragmented provider-centered care model to a patient-centered model, with greater care coordination and alignment among providers focused on improving value. VBHC models allow innovative strategies to proactively invest resources to promote value (e.g., the use of nurse navigators) while eliminating unnecessary resources that do not promote value. However, major concerns regarding VBHC include the absence of medical and socioeconomic risk stratification as well as decreased access for higher-risk patients.This article identifies the benefits and potential unintended consequences of VBHC reform, with a focus on joint arthroplasty. We also discuss some potential strategies to promote innovation and improve value without compromising access for vulnerable patients.

Timing and Type of Bariatric Surgery Preceding Total Knee Arthroplasty Leads to Similar Complications and Outcomes

BACKGROUND

No consensus exists regarding the appropriate timing of bariatric surgery (BS) or the complication profiles between Roux-en-Y Gastric Bypass (RYGB) and sleeve gastrectomy (SG) prior to total knee arthroplasty (TKA). We sought to compare 90-day medical and up to two-year surgical complications and revisions among (1) BS performed 6 months and 1 year prior to TKA; (2) between BS types (RYGB and SG) prior to TKA; and (3) with comparison to 2 non-BS cohorts of morbidly and nonmorbidly obese patients.

METHODS

We queried a national database to identify patients undergoing BS (RYGB and SG) prior to TKA from 2010 to 2020. Timing (six-month and one-year intervals) and type of BS (RYGB and SG) were identified. Cohorts without prior BS served as comparators: BMI, kg/m² > 40 and 20-35. Ninety-day to two-year medical/surgical complications and revisions were assessed. Multivariate regression analyses examined the risk factors for prosthetic joint infections (PJIs) and revisions.

RESULTS

The timing of BS (6 months and 1 year) had similar incidences of medical/surgical complications and revisions, with both lower than the BMI > 40 cohort (P < .001). Differences between types of BS were also lower than the BMI > 40 cohort (P < .001). The BMI 20-35 had lower complications and revisions among all cohorts. No differences were observed between BS timing or type as risk-factors for PJIs and revisions.

CONCLUSION

Timing (6 months or 1 year prior to TKA) and type of BS shared similar complication profiles, lower than BMI > 40 and higher than BMI 20-35. These findings support a surgeon's decision to proceed with TKA at six months post-BS if indicated.

Does bariatric surgery really benefit patients before total knee arthroplasty? A systematic review and meta-analysis

PURPOSE

At present, whether bariatric surgery before total knee arthroplasty (TKA) affects the prognosis of subsequent TKA has been a topic of debate in the academic community. The primary purpose of this systematic review and meta-analysis was to investigate the effect of previous bariatric surgery on prosthetic revisions and postoperative complications after TKA.

METHODS

We included prospective and observational studies published in English involving patients who had undergone bariatric surgery prior to TKA and compared them with morbidly obese patients with no history of bariatric surgery. The Newcastle-Ottawa Scale was used to assess the methodological quality of non-randomized case-control studies. The outcomes included revisions, infections, venous thromboembolism (VTE), blood transfusion, mortality, stiffness or manipulation under anesthesia (MUA), and medical complications.

RESULTS

Of the 9 included studies with 166047 patients, 4 were matched cohort studies, 2 were unmatched cohort, and 3 were database studies. Methodological quality was high in ten studies and moderate in thirteen studies. Our analysis demonstrated that patients with TKA who had undergone prior bariatric surgery were associated with increased risks of long-term revision, long-term infection, long-term stiffness or MUA and blood transfusions, whereas prior bariatric surgery did not increase the risk of short-term complications and short-term revision.

CONCLUSION

This meta-analysis highlights the risks of bariatric surgery prior to TKA and suggests that prior bariatric surgery may increase the risk of perioperative blood transfusion and also the risk of revision and infection in long-term follow-up. Surgeons can use this information to help counsel patients undergoing bariatric surgery before primary TKA.

Does Bariatric Surgery Prior to Primary Total Knee Arthroplasty Improve Outcomes?

BACKGROUND

Recent advancements in bariatric surgical techniques have increased its utilization for the management of morbid obesity prior to total knee arthroplasty (TKA). We hypothesized that bariatric surgery prior to primary TKA would mitigate postoperative complications and improve implant survivorship.

METHODS

A retrospective review from 1992-2020 identified 205 bariatric surgery patients with subsequent primary TKA. This cohort was matched 1:1:1 to patients without bariatric surgery and with BMI <40 kg/m² and BMI ≥40 kg/m². Revisions, reoperations, and 90-day complications were evaluated. Subgroup analysis evaluated bariatric patients with BMI >40 kg/m² at TKA, the time between surgeries, and compared historical to contemporary bariatric techniques.

RESULTS

Bariatric patients demonstrated higher revision rates than low (HR 4, P < .01) and high BMI (HR 9, P < .01) controls, and increased reoperations when compared to the low (HR 2, P < .01) and high BMI (HR 6, P < .01) groups. Reoperation for instability was more common in bariatric patients than low (HR 15, P = .01) and high BMI (HR 17, P < .01) groups. Reoperation for infection was higher in bariatric patients relative to the high BMI (HR 6, P = .03), but not the low BMI cohort (HR 3, P = .06). There was no difference in 90-day complications (P = .33). Bariatric patients with high BMI and contemporary bariatric procedures did not significantly impact complications or survivorship, but bariatric surgery >2 years before TKA was associated with higher revision rates (P = .01).

CONCLUSION

This study found that bariatric surgery patients who undergo primary TKA have worse implant survivorship, mostly related to infection and instability. Further investigation into perioperative optimization is warranted.

LEVEL OF EVIDENCE

Prognostic Level IV.

Morbid Obesity and Severe Knee Osteoarthritis: Which Should Be Treated First?

BACKGROUND

There are limited prospective data, and conflicting retrospective data, providing guidance on how to optimally manage patients with morbid obesity and severe knee osteoarthritis. This study sought to review the effect of bariatric surgery on knee pain and knee surgery 30-day outcomes, as well as assess whether the sequence of bariatric and knee surgery has any effect on 30-day complications.

METHODS

A retrospective chart review of all patients undergoing laparoscopic sleeve gastrectomy (LSG) from July 2006 to July 2016 at a university hospital was performed. Patients with knee pain or knee surgery (pre- or post-LSG) were identified using bariatric and orthopedic clinic notes. Those who had improvement in knee pain following LSG resulting in removal from orthopedic surgery waitlist were identified. We also assessed surgical outcomes in patients undergoing knee arthroscopy or total knee arthroplasty (TKA) followed by LSG compared to patients undergoing LSG followed by knee arthroscopy or TKA.

RESULTS

During our study timeframe, 355 patients underwent LSG. Knee pain was documented in 150 (42.2%) patients, and orthopedic surgery consultation was completed for 57 (38.0%) patients with knee pain. Orthopedic intervention was performed prior to LSG for 24 patients and after LSG for 27 patients. Procedures were a combination of arthroscopy (18) and TKA (33). Six patients were removed from the waitlist for TKA following LSG due to resolution of symptoms. Order of interventions did not affect 30-day complications for patients undergoing LSG and arthroscopy (16% arthroscopy first, 0% LSG first, p = 0.43). A higher rate of LSG complications was noted in patients who underwent TKA prior to LSG (25% vs 0%, p = 0.04). There were no differences in TKA complications (8.3% TKA first, 4.8% LSG first, p = 1.00).

CONCLUSION

In a small number of patients with morbid obesity and severe knee osteoarthritis, orthopedic intervention can be delayed and potentially avoided by undergoing LSG. In our study, 6/57 (10.5%) of patients with orthopedic consultation prior to LSG saw resolution of symptoms of knee pain. Referral to bariatric surgery should be considered for patients with morbid obesity and severe knee osteoarthritis.

Bariatric surgery and total knee/hip arthroplasty: an analysis of the impact of sequence and timing on outcomes

BACKGROUND

Patients with morbid obesity may require both bariatric surgery and total knee/hip arthroplasty (TKA/THA). How to sequence these two procedures with better outcomes remains largely unstudied.

METHODS

This cohort study extracted claims data on patients with an obesity diagnosis that received both bariatric surgery and TKA/THA surgery within 5 years of each other (Premier Healthcare database 2006-2019). Overall, 1894 patients received bariatric surgery before TKA or THA, while 1000 patients underwent TKA or THA before bariatric surgery. Main outcomes and measures include major complications (acute renal failure, acute myocardial infarction, other cardiovascular complications, sepsis/septic shock, pulmonary complications, pulmonary embolism, pneumonia, and central nervous system-related adverse events), postoperative intensive care unit utilization, ventilator utilization, 30-day readmission, 90-day readmission, 180-day readmission and total hospital length of stay after the second surgery. Regression models measured the association between the complications and sequence of TKA/THA and bariatric surgery.

RESULTS

Undergoing TKA/THA before bariatric surgery (compared with the reverse) was associated with higher odds of major complications (7.0% vs 1.9%; adjusted OR 4.8, 95% CI 3.1, 7.6, p<0.001). Similar patterns were also observed for intensive care unit admission, ventilator use postoperatively, 30-day, and 90-day readmissions. Patients who received a second surgery within 6 months of their first surgery exhibited worse outcomes, especially among the TKA/THA first patient cohort. Major complication incidences occurred at 20.5%, 12.5%, 5.1%, 5.0%, 5.8% and 8.5% with time between TKA/THA and bariatric surgery at <6 months, 6 months-1 year, 1-2, 2-3, 3-4 and 4-5 years, respectively.

CONCLUSIONS

Patients who require both bariatric surgery and TKA/THA should consider bariatric surgery before TKA/THA as it is associated with improved outcomes. Procedures should be staged beyond 6 months.

Pre-Operative Bariatric Surgery Imparts An Increased Risk of Infection, Re-Admission and Operative Intervention Following Elective Instrumented Lumbar Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To evaluate the impact of bariatric surgery on patient outcomes following elective instrumented lumbar fusion.

METHODS

A retrospective review of a prospectively collected database was performed. Patients who underwent a bariatric procedure prior to an elective instrumented lumbar fusion were evaluated. Lumbar procedures were performed at a large academic medical center from 1/1/2012 to 1/1/2018. The primary outcome was surgical site infection (SSI) requiring surgical debridement. Secondary outcomes were prolonged wound drainage requiring treatment, implant failure requiring revision, revision secondary to adjacent segment disease (ASD), and chronic pain states. A randomly selected, surgeon and comorbidity-matched group of 59 patients that underwent an elective lumbar fusion during that period was used as a control. Statistical analysis was performed using Student's two-way t-tests for continuous data, with significance defined as P < .05.

RESULTS

Twenty-five patients were identified who underwent bariatric surgery prior to elective lumbar fusion. Mean follow-up was 2.4 ± 1.9 years in the bariatric group vs. 1.5 ± 1.3 years in the control group. Patients with a history of bariatric surgery had an increased incidence of SSI that required operative debridement, revision surgery due to ASD, and a higher incidence of chronic pain. Prolonged wound drainage and implant failure were equivalent between groups.

CONCLUSION

In the present study, bariatric surgery prior to elective instrumented lumbar fusion was associated increased risk of surgical site infection, adjacent segment disease and chronic pain when compared to non-bariatric patients.

Obesity, Bariatric Surgery, and Hip/Knee Arthroplasty Outcomes

Obesity is an independent risk factor for osteoarthritis due to mechanical and inflammatory factors. The gold-standard treatment of end-stage knee and hip osteoarthritis is total joint arthroplasty (TJA). Weight loss decreases progression of osteoarthritis and complications following TJA in patients with obesity. Bariatric surgery allows significant, sustained weight loss and comorbidity resolution in patients with morbid obesity. Existing data describing bariatric surgery on TJA outcomes are limited but suggest a benefit to bariatric surgery prior to TJA. Further studies are needed to determine optimal risk stratification, bariatric procedure selection, and timing of bariatric surgery relative to TJA.

A Literature Review and Summary Recommendations of the Impact of Bariatric Surgery on Orthopedic Outcomes

Many surgeons recommend weight loss in preparation for orthopedic procedures, yet the impact of surgically induced weight loss before orthopedic procedures is not clear. We undertook a literature review to assess the impact of bariatric surgery on the outcomes of total joint arthroplasty (TJA). We searched PubMed, Medline, Cochrane Library, and Google Scholar for studies (2010-2017) that evaluated the associations between obesity, bariatric surgery, and orthopedic surgery. Nine studies found that prior bariatric surgery decreased major and minor post-operative complications, operating room (OR) time, length of stay (LOS), risk of re-operation, and 90-day re-admissions after TJA. Two studies found that bariatric surgery patients had a higher reoperation rate for stiffness and infection as well as need for revision within 90 days after TJA. One meta-analysis found no statistically significant differences in wound infections, revisions, or mortality irrespective of bariatric surgery status; and another meta-analysis showed reduced medical complications, LOS, and OR time. Our review highlights many gaps in our knowledge and the need for additional studies to define the impact of the bariatric-first approach on TJA outcomes. We propose a framework from lessons learned to raise awareness of medical and surgical options of weight management before elective orthopedic operations in patients with obesity.

Preoperative Risk Factor Screening Protocols in Total Joint Arthroplasty: A Systematic Review

BACKGROUND

Preoperative optimization protocols targeting potentially modifiable risk factors could prove beneficial in reducing the rate of complications in lower extremity total joint arthroplasty (LE-TJA). We aimed to summarize the evidence on preoperative screening protocols targeting modifiable risk factors to assess their effect on postoperative outcomes following primary LE-TJA.

METHODS

A literature search of MEDLINE, EMBASE, CINAHL, and Cochrane Library databases was performed in August 2019. The bibliographies of relevant publications were searched for further applicable studies. Included studies were required to report at least one outcome including prosthetic joint infection/surgical site infection (PJI/SSI), hospital length of stay (LOS), disposition, 90-day emergency department visits, or hospital readmissions after implementation of an evidence-based preoperative optimization protocol targeting modifiable risk factors. Methodological quality of included studies was assessed using the methodological index for non-randomized studies (MINORS) criteria.

RESULTS

A total of 8 retrospective cohort studies including 9915 patients were reviewed. Implementation of preoperative optimization protocols were associated with reductions in SSI (0.56% vs. 2.60%; RR 0.21 [95% CI 0.12 to 0.37]; P < .00001), hospital LOS, mean cost of care, and hospital readmission rates. The mean MINORS score for comparative studies was 16.285.

CONCLUSIONS

Implementation and compliance with evidence-based preoperative protocols for optimization of modifiable risk factors is associated with overall improved outcomes following LE-TJA. SSI, hospital LOS, average total cost of care, and hospital readmission rates were favorable in those cohorts subjected to a preoperative intervention protocol. Future prospective studies are necessary for further refinement of preoperative optimization protocols and referral algorithms, without compromising patients' access to surgery.

LEVEL OF EVIDENCE

III, Systematic Review.

Nutritional Counseling Program for Morbidly Obese Patients Enables Weight Optimization for Safe Total Joint Arthroplasty

Obesity affects one-third of total joint arthroplasty (TJA) patients and is the most common modifiable risk factor for increased complications in the TJA population. The authors' institution implemented a body mass index (BMI) cutoff of 40 kg/m² to define appropriate TJA candidates. Patients above the cutoff were referred for nutritional counseling. The study objective was to evaluate the efficacy of this protocol in optimizing patient BMI for safe and successful TJA. Between 2016 and 2018, the authors examined 133 patients (mean age, 62.6 years) with a BMI greater than 40 kg/m² seeking TJA (94 knee, 39 hip) seen by an arthroplasty surgeon and then a dietitian. Outcomes included weight loss, change in BMI, duration of counseling, and surgical status. For postoperative patients, 90-day complications were recorded. A total of 102 (92%) patients achieved weight loss during a mean 154 days (range, 8-601 days). Patients lost a mean of 17 lb, lowering their BMI by 2.7 points (range, +6.3 to -17.7 points). Twenty-two patients discontinued nutritional counseling after 1 visit, most commonly secondary to cost when not covered by insurance. Seventy-one patients successfully underwent TJA, representing 64% of those patients who participated in nutritional counseling. Complications included delayed wound healing (n=2), periprosthetic fracture (n=2), infection (n=1), cellulitis (n=1), and peroneal nerve palsy (n=1). Surgeons must actively counsel obese patients about weight optimization as part of the preoperative standard of care. Nutritional counseling with a dietitian and follow-up with the surgeon translated to safe and successful TJA in a majority of patients. [Orthopedics. 2020;43(4):e316-e322.].

Preoperative Bariatric Surgery Utilization Is Associated With Increased 90-day Postoperative Complication Rates After Total Joint Arthroplasty

BACKGROUND

This study evaluates the incidence of bariatric surgery (BS) before total joint arthroplasty (TJA) in New York State and compares patient comorbidities and 90-day postoperative complications of patients with and without BS before TJA.

METHODS

The NY Statewide Planning and Research Cooperative System database between 2005 and 2014 was reviewed and 343,710 patients with TJA were identified. Patients were stratified into the following three cohorts: group 1 (patients who underwent BS < 2 years before TJA [N = 1,478]); group 2 (obese patients without preoperative BS [N = 60,259]); and group 3 (nonobese patients without preoperative BS [N = 281,973]). Principal outcomes measured were patient comorbidities, 90-day complication rates, length of inpatient stay, discharge disposition, mortality rate, and total hospital costs.

RESULTS

BS before TJA incidence increased from 0.11 of 100,000 to 2.4 of 100,000 from 2006 to 2014. Preoperative BS did not notably change the number of patient comorbidities at the time of TJA. Group 1 had more patients with 90-day complications (40.7% versus 36.0%, P < 0.001) than group 2. No difference was found between group 1 and the other groups in home discharge, pulmonary embolism, deep vein thrombosis, and mortality rates. Total hospital costs were higher for group 1 ($18,869 ± 9,022 versus $17,843 ± 8,095, P < 0.001) compared with those for group 2.

CONCLUSION

BS before TJA has increased annually over a 10-year period in New York State and is associated with greater 90-day postoperative complication rates and higher immediate hospital costs when compared with obese patients without BS.

Effect of bariatric surgery on outcomes in the operative treatment of hip fractures

INTRODUCTION

Few studies have evaluated the effect of prior bariatric surgery on outcomes following the operative treatment of hip fractures. The purpose of this study is to evaluate these metrics in a population of bariatric surgery patients compared to a control group who were operatively treated for hip fractures.

MATERIALS AND METHODS

The California Office of Statewide Health Planning & Development (OSHPD) discharge database was accessed to identify patients who sustained a hip fracture between 2000-2014. CPT codes were utilized to identify patients who had a prior history of bariatric surgery within this time period. A control cohort of patients who had undergone previous appendectomy were queried similarly. The study evaluated complication rates and inpatient mortality at 30- and 90-days postoperatively as well as 30- and 90-day readmission rates.

RESULTS

There were 1,327 bariatric and 2,127 control patients identified. Survival rates were significantly lower in bariatric patients compared to controls (87.2% vs. 91.8%, p = 0.048) at 5 years. After controlling for confounders, bariatric patients had higher 30- (OR 1.46, p = 0.005) and 90-day (OR 1.38, p = 0.011) readmission rates. There were no differences in all-cause complication and inpatient mortality rates between groups at 30 or 90 days.

DISCUSSION

Bariatric surgery patients are at increased risk of readmission after hip fracture surgery. Further research is warranted to delineate potential risk factors and mitigate readmission in these patients.

LEVEL OF EVIDENCE

III.

Host-related factors for venous thromboembolism following total joint replacement: A meta-analysis of 89 observational studies involving over 14 million hip and knee replacements

BACKGROUND

Venous thromboembolism, a potential complication of total joint replacement, is associated with preventable mortality and morbidity and is likely to be influenced by host-related factors such as sociodemographic characteristics, body mass index, medical and surgical histories, as well as circulating biomarkers. We conducted a systematic review and meta-analysis to assess the associations between host-related factors and venous thromboembolism risk following total hip and knee replacements.

METHODS

We searched MEDLINE, Embase, Web of Science, and Cochrane Library to March 2018 for longitudinal studies reporting these associations. Summary measures of association were relative risks (95% confidence intervals).

RESULTS

We identified 89 studies with data on 14,763,963 joint replacements and 150,086 venous thromboembolism events. Comparing males to females, age ≥70 to <70 years, and blacks to whites, relative risks for venous thromboembolism were 0.83 (0.75-0.91), 1.24 (1.03-1.50), and 1.26 (1.20-1.31) respectively. Comparing body mass indices ≥25 vs. <25; ≥30 vs. <30; and ≥50 vs. <50 kg/m², relative risks were 1.40 (1.24-1.57); 1.65 (1.23-2.22); and 1.72 (1.10-2.67) respectively. Histories of venous thromboembolism; cardiovascular disease; congestive heart failure; cardiac arrhythmia; chronic pulmonary disease; renal disease; neurological disease; fluid & electrolyte imbalance; bariatric surgery; and comorbidity indices were associated with increased venous thromboembolism risk. Comparing a total knee with a hip replacement, the relative risk for venous thromboembolism was 1.69 (1.32-2.15).

CONCLUSIONS

Enhanced venous thromboembolism prophylaxis should be considered in those with nonmodifiable risk factors such as older black female knee replacement patients. Modifiable risk factors such as high body mass index and fluid & electrolyte imbalance should be addressed prior to elective surgery.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2018: CRD42018089625.

Does Bariatric Surgery Normalize Risks After Total Knee Arthroplasty? Administrative Medicare Data

Patients with morbid obesity, defined as body mass index of greater than 40 kg/m², are being referred for weight loss and bariatric surgery before being accepted for a total knee arthroplasty (TKA). Previous studies have identified the risks associated with doing a TKA in an individual with an increased body mass index. We now present data identifying the same risks in individuals who have undergone bariatric surgery before submitting to TKA.

The Effect of Bariatric Surgery Prior to Lower-Extremity Total Joint Arthroplasty: A Systematic Review

BACKGROUND

Obesity is an independent risk factor for osteoarthritis and has been associated with increased rate of complications following lower-extremity total joint arthroplasty (TJA). Bariatric surgery (BS) is a surgical option for weight loss and for reducing obesity-related comorbidities in morbidly obese patients.

PURPOSE/QUESTIONS

The goal of this systematic review was to answer the following questions: (1) Does BS prior to TJA correlate with lower post-operative complication rates in morbidly obese patients undergoing TJA? (2) Does BS have an impact on revision rates following TJA?

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and checklist, a systematic review of medical databases (PubMed/ MEDLINE, Cochrane Library, Web of Science, and Clinicaltrials.gov) was undertaken for articles published in English from January 1990 to September 2018. Inclusion criteria were studies that included at least ten patients who underwent BS prior to TJA, collected data on complications or other outcomes, and followed patients for at least 90 days after TJA. A descriptive and critical analysis of the results was performed.

RESULTS

From 799 studies, 13 met inclusion criteria. A total of 11,770 patients who had undergone bariatric surgery prior to TJA were analyzed. The quality of the evidence ranged between moderate and high. There was no consensus on the effect of previous BS on early- to short-term outcomes reported after TJA.

CONCLUSION

The literature remains conflicted on the impact of BS prior to TJA on early, short-term, and long-term complications after TJA. Additional well-matched, observational studies may further our understanding of the impact of BS prior to TJA on outcomes. In particular the effect of various types of BS prior to TJA on outcomes has yet to be elucidated. Ideally, prospective studies with higher level of evidence will be more definitive on the effects of BS prior to TJA.Prospero Registration Number: CRD42016043025.

Ninety-Day Costs, Reoperations, and Readmissions for Primary Total Hip Arthroplasty Patients of Varying Body Mass Index Levels

BACKGROUND

The purpose of this study is to compare 90-day costs and outcomes for primary total hip arthroplasty patients between a nonobese (body mass index, 18.5-24.9) vs overweight (25-29.9), obese (30-34.9), severely obese (35-39.9), morbidly obese (40-44.9), and super obese (45+) cohorts.

METHODS

We conducted a retrospective review of an institutional database of primary total hip arthroplasty patients from 2006 to 2013. Thirty-three super-obese patients were identified, and the other 5 cohorts were randomly selected in a 2:1 ratio (n = 363). Demographics, 90-day outcomes (costs, reoperations, and readmissions), and outcomes after 3 years (revisions and change scores for Short-Form Health Survey, Harris Hip Score, and Western Ontario and McMaster Universities Arthritis Index) were collected. Costs were determined using unit costs from our institutional administrative data for all in-hospital resource utilization. Comparisons between the nonobese and other groups were made with Kruskal-Wallis tests for non-normal data and chi-square and Fisher exact test for categorical data.

RESULTS

The 90-day costs in the morbidly obese ($13,134 ± $7250 mean ± standard deviation, P < .01) and super-obese ($15,604 ± 6783, P < .01) cohorts were significantly greater than the nonobese cohorts ($10,315 ± 1848). Only the super-obese cohort had greater 90-day reoperation and readmission rates than the nonobese cohort (18.2% vs 0%, P < .01 and 21.2% vs 4.5%, P = .02, respectively). Reoperations and septic revisions after 3 years were greater in the super-obese cohort compared to the nonobese cohort 21.2% versus 3.0% (P = .01) and 18.2% versus 1.5% (P = .01), respectively. Improvements in Short-Form Health Survey, Harris Hip Score, and Western Ontario and McMaster Universities Arthritis Index were comparable in all cohorts.

CONCLUSION

Super-obese patients have greater risks and costs compared to nonobese patients, but also have comparable quality of life improvements.

Cost-Effectiveness of Total Hip Arthroplasty Versus Nonoperative Management in Normal, Overweight, Obese, Severely Obese, Morbidly Obese, and Super Obese Patients: A Markov Model

BACKGROUND

We estimated the cost-effectiveness of performing total hip arthroplasty (THA) vs nonoperative management (NM) among 6 body mass index (BMI) cohorts.

METHODS

We constructed a state-transition Markov model to compare the cost utility of THA and NM in the 6 BMI groups over a 15-year period. Model parameters for transition probability (risk of revision, re-revision, and death), utility, and costs (inflation adjusted to 2017 US dollars) were estimated from the literature. Direct medical costs of managing hip arthritis were accounted in the model. Indirect societal costs were not included. A 3% annual discount rate was used for costs and utilities. The primary outcome was the incremental cost-effectiveness ratio (ICER) of THA vs NM. One-way and Monte Carlo probabilistic sensitivity analyses of the model parameters were performed to determine the robustness of the model.

RESULTS

Over the 15-year time period, the ICERs for THA vs NM were the following: normal weight ($6043/QALYs [quality-adjusted life years]), overweight ($5770/QALYs), obese ($5425/QALYs), severely obese ($7382/QALYs), morbidly obese ($8338/QALYs), and super obese ($16,651/QALYs). The 2 highest BMI groups had higher incremental QALYs and incremental costs. The probabilistic sensitivity analysis suggests that THA would be cost-effective in 100% of the normal, overweight, obese, severely obese, and morbidly obese simulations, and 99.95% of super obese simulations at an ICER threshold of $50,000/QALYs.

CONCLUSION

Even at a willingness-to-pay threshold of $50,000/QALYs, which is considered low for the United States, our model showed that THA would be cost-effective for all obesity levels. BMI cut-offs for THA may lead to unnecessary loss of healthcare access.

Choices, Compromises, and Controversies in Total Knee and Total Hip Arthroplasty Modifiable Risk Factors: What You Need to Know

BACKGROUND

Total joint arthroplasty has historically been very successful for most patients, yet some still incur a complication. In an era of value-based care, certain efforts need to be taken to optimize patients' risk profile before surgery to decrease the chances of readmission or surgical complication.

METHODS

We reviewed 10 key medical conditions and lifestyle factors that surgeons should improve before pursuing total joint arthroplasty and provide a summary of the available literature to guide certain optimization thresholds.

RESULTS

With careful attention to and the creation of a preoperative checklist, surgeons can identify key domains, including morbid obesity, malnutrition, diabetes, smoking, opioid use, poor dentition, cardiovascular disease, preoperative anemia, staphylococcus colonization, and psychological disorders and intervene based on an individual's areas of deficiencies.

CONCLUSION

By following stringent protocols and rescheduling surgery until optimization has occurred, we can work to provide patients the best chance for a successful outcome with an elective hip or knee arthroplasty.

Dislocation rate increases with bariatric surgery before total hip arthroplasty

INTRODUCTION

Annually in the USA, 113,000 patients with refractory obesity undergo bariatric surgery (BS), and a subset does so in order to lower body mass index to become a more desirable total hip arthroplasty (THA) candidate. This study aims to evaluate THA risk with and without bariatric surgery.

METHODS

12,160 patients were identified in a claim-based review of the entire Medicare database with ICD-9 codes to identify patients in three groups. Patients who underwent BS prior to THA (Group I: 1,545 experimental group) and two control groups that did not undergo BS but had either a body mass index >40 (Group II: 6,918 bariatric control) or <25 (Group III: 3,697 normal weight control). Preoperative demographics/comorbidities and short-term medical (30 day) and long-term surgical (90-day and 2-year) complications were evaluated.

RESULTS

Group I had female predominance, youngest age, and highest incidence of: deficiency anaemia, cardiovascular disease, liver disease, diabetes, polysubstance abuse, psychiatric disorders and smoking. At 2 years, Group I had approximately twice the dislocation and revision risk compared to both Groups II and III; Groups I and II had over four times the risk of infection and wound complications compared to Group III.

CONCLUSION

In the Medicare population, these patients continue to have complication rates similar to and sometimes greater than obese patients with no prior bariatric surgery. Greater dislocation risk is possibly due to ligamentous laxity related to decreased collagen/elastin and/or component malposition due to intraoperative visualisation challenges.

Bariatric surgery before elective posterior lumbar fusion is associated with reduced medical complications and infection

BACKGROUND CONTEXT

Severely obese patients with operative spinal pathology present a challenge to the spine surgeon, given the increased complication risk.

PURPOSE

We aimed to determine the impact of bariatric surgery (BS) on perioperative complications of posterior lumbar fusion.

STUDY DESIGN

This is a retrospective cohort study.

PATIENT SAMPLE

Patients undergoing posterior lumbar fusion surgery in the State Inpatient Databases of New York, Florida, North Carolina, Nebraska, Utah, and California comprised the patient sample.

OUTCOMES

Thirty-day medical complications, surgical complications (nerve injury, infection, revision), death, readmission, and hospital length of stay (LOS) were the study's outcomes.

METHODS

We analyzed 156,517 patients using International Classification of Diseases, Ninth Revision codes. Patients were categorized into three groups: Group 1: history of BS and obesity, Group 2: severe obesity, body mass index (BMI)>40 (severely obese), and Group 3: normal weight, BMI<25 (non-obese). Logistic and linear multivariate regressions were performed to compare complications and LOS, respectively, between BS and severely obese groups and BS and non-obese groups while controlling for confounders. There were no sources of funding for this study.

RESULTS

There were 590 patients with BS, 5,791 severely obese, and 150,136 non-obese. Comparing BS with severely obese, BS had significantly lower rates of respiratory failure (odds ratio [OR] 0.59, p=.019), urinary tract infection (OR 0.64, p=.031), acute renal failure (OR 0.39, p=.007), overall medical complications (OR 0.59, p<.001), and infection (OR 0.65, p=.025). Bariatric surgery also had significantly lower hospital LOS (B=-0.46, p=.01). Comparing BS with non-obese, there were no significant differences in medical complications; however, BS had significantly higher rates of infection (OR 2.70, p<.001), reoperation (OR 2.05, p=.045), and readmission (OR 1.89, p<.001).

CONCLUSION

Bariatric surgery before elective posterior lumbar fusion mitigates risk of medical complications and infection. However, these patients still have increased risk of infection, revision surgery, and readmission compared with patients with normal BMI. Surgeons might consider referral for BS for the severely obese patient before undergoing spine surgery.

Bariatric Surgery Improves Outcomes After Lower Extremity Arthroplasty in the Morbidly Obese: A Propensity Score-Matched Analysis of a New York Statewide Database

BACKGROUND

The purpose of this study was to compare risks for revision and short-term complications after total joint arthroplasty (TJA) in matched cohorts of morbidly obese patients, receiving and not receiving prior bariatric surgery.

METHODS

Patients undergoing elective TJA between 1997 and 2011 were identified in a New York Statewide database, analyzing total knee arthroplasty (TKA) and total hip arthroplasty (THA) separately. Propensity scores were used to match morbidly obese patients receiving and not receiving bariatric surgery prior to TJA. Cox proportional hazard modeling assessed revision risk. Logistic regression evaluated odds for complications.

RESULTS

For TKA, 2636 bariatric surgery patients were matched to 2636 morbidly obese patients. For THA, 792 bariatric surgery patients were matched to 792 morbidly obese patients. Matching balanced all covariates. Bariatric surgery reduced co-morbidities prior to TJA (TKA P < .0001; THA P < .005). Risks for in-hospital complications were lower for THA and TKA patients receiving prior bariatric surgery (odds ratio [OR] 0.25, P < .001; and OR = 0.69, P = .021, respectively). Risks for 90-day complications were lower for TKA (OR 0.61, P = .002). Revision risks were not different for either THA (P = .634) or TKA (P = .431), nor was THA dislocation risk (P = 1.000).

CONCLUSION

After accounting for relevant selection biases, bariatric surgery prior to TJA was associated with reduced co-morbidity burden at the time of TJA and with reduced post-TJA complications. However, bariatric surgery did not reduce the risk for revision surgery for either TKA or THA.

Ninety-Day Costs, Reoperations, and Readmissions for Primary Total Knee Arthroplasty Patients With Varying Body Mass Index Levels

BACKGROUND

We compared 90-day costs and outcomes for primary total knee arthroplasty patients among nonobese (body mass index [BMI] 18.5-24.9), overweight (25-29.9), obese (30-34.9), severely obese (35-39.9), morbidly obese (40-49.9), and super-obese (50+) cohorts.

METHODS

We conducted a retrospective review of an institutional database of total knee arthroplasty patients from 2006 to 2013 with a minimum of 3-year follow-up. Sixty-five super-obese patients were identified, and five other cohorts were randomly selected in a 2:1 ratio (total, n = 715). Demographics, 90-day outcomes (costs, reoperations, and readmissions), and outcomes after 3 years (revisions and change scores for Short-Form Health Survey [SF-12], Knee Society Scores, and Western Ontario and McMaster Universities Arthritis Index) were aggregated.

RESULTS

The 90-day costs were significantly greater in the morbidly obese ($11,568 ± $1,960) and super-obese ($14,021 ± $7,903) cohorts relative to the smaller BMI cohorts ($9,938 - $10,352). The increased cost from readmissions was the main driver of costs. The outcome change scores were similar across all the BMI cohorts for Knee Society Scores, SF-12 Mental Health Composite Score, and Western Ontario and McMaster Universities Arthritis Index, but not for the SF-12 Physical Health Composite Score. At the midterm follow-up, there was no statistical difference in repeat surgery or aseptic revision rates. Septic revisions were significantly greater in the super-obese cohort relative to the other cohorts (6.2% vs 0.8-3.1%).

CONCLUSION

Health-care policy based purely on the economic costs may place morbidly obese and super-obese patients at risk of losing arthroplasty care, thereby denying them access to the comparable quality of life improvements.

Cost-Effectiveness of Total Knee Arthroplasty vs Nonoperative Management in Normal, Overweight, Obese, Severely Obese, Morbidly Obese, and Super-Obese Patients: A Markov Model

BACKGROUND

We estimated the cost-effectiveness of performing total knee arthroplasty (TKA) vs nonoperative management (NM) among 6 body mass index (BMI) cohorts.

METHODS

A Markov model was used to compare the cost-utility of TKA and NM in 6 BMI groups (nonobese [BMI 18.5-24.9], overweight [25-29.9], obese [30-34.9], severely obese [35-39.9], morbidly obese [40-49.9], and super-obese [50+] patients) over a 15-year period. Model parameters for transition probability (ie, revision, re-revision, death), utility, and costs were estimated from the literature. Direct medical costs but not indirect societal costs were included in the model. Costs and utilities were discounted 3% annually. The primary outcome was the incremental cost-effectiveness ratio (ICER) of TKA vs NM. One-way and probabilistic sensitivity analyses of the model parameters were performed to determine the robustness of the model.

RESULTS

Over the 15-year period, the ICERs for the TKA vs NM for the different BMI categories were nonobese ($3317/quality-adjusted life years [QALYs]), overweight ($2837/QALY), obese ($2947/QALY), severely obese ($3536/QALY), morbidly obese ($5531/QALY), and super-obese ($11,878/QALY). The higher BMI groups tended to have higher incremental QALYs and also higher incremental costs. The probabilistic sensitivity analysis with an ICER threshold of $30,000/QALY showed that TKA would be cost-effective in 100% of simulations of patients with a BMI<50 and 99.16% of super-obese simulations.

CONCLUSION

While performing TKA on super-obese patients is more expensive, the substantial improvements in patient outcomes make it cost-effective. Therefore, withholding TKA care based on a BMI would lead to an unjustified loss of health-care access.

Bundle Payment for Musculoskeletal Care: Current Evidence (Part 1)

In the face of escalating costs and variations in quality of care, bundled payment models for total joint arthroplasty procedures are becoming increasingly common, both through the Centers for Medicare & Medicaid Services and private payer organizations. The effective implementation of these payment models requires cooperation between multiple service providers to ensure economic viability without deterioration in care quality. This article introduces a stepwise model for the financial analysis of bundled contracts for use in negotiations between hospitals and private payer organizations.

Preoperative Bariatric Surgery and the Risk of Readmission Following Total Joint Replacement

The purpose of this study was to compare nonelective and all-cause readmission rates and to identify risk factors for readmission of total joint arthroplasty (TJA) patients who had preoperative bariatric surgery (BS) compared with TJA patients without preoperative BS. The New York Statewide Planning and Research Cooperative System database was queried to identify 343,710 TJA patients between 2005 and 2014. Three patient groups were evaluated: group 1 (patients with preoperative BS within 2 years of TJA [N=1478]); group 2 (obese patients without preoperative BS [N=60,259]); and group 3 (nonobese patients without preoperative BS [N=281,973]). Nonelective and all-cause readmission rates (30 days, 90 days, and 1 year) were compared, and multivariate analyses of readmission risk factors were performed. Group 1 had no significant difference in nonelective readmission rates compared with groups 2 and 3. However, when elective TJA readmissions were included, group 1 had significantly higher all-cause readmission rates at 30 days, 90 days, and 1 year compared with groups 2 and 3. Bariatric surgery was not a risk factor for nonelective readmissions at any time point. When elective TJA admissions were included, BS was an independent risk factor for all-cause readmission at all time points. Patients who have BS prior to TJA do not have higher nonelective readmission rates than obese TJA patients without BS. Bariatric surgery is not a risk factor for nonelective readmissions. However, BS is a significant predictor of elective TJA admissions up to 1 year following the index TJA. [Orthopedics. 2018; 41(2):107-114.].

Anaesthetic Preparation of Obese Patients: Current Status on Optimal Work-up

PURPOSE OF REVIEW

With the prevalence of obesity rapidly growing, bariatric anaesthesia becomes everyday anaesthesia rather than a subspecialty. In this review, we are aiming to draw attention to this complex group of patients and their comorbidities, relevant to everyday practice for contemporary anaesthetists.

RECENT FINDINGS

We wanted to focus greatly on sleep-related breathing disorders, because preoperative screening, diagnosis and treatment of the aforementioned make a huge impact in the improvement of preoperative morbidity and mortality, including positive effects on the cardiovascular system. The overview is touching on main obesity-related comorbidities and guides the anaesthetist and associated health professionals on how to approach and manage them. A multidisciplinary approach widely used in bariatric care may be adopted in the care of obese patients in order to reduce preoperative morbidity and mortality. We advocate the early involvement of the anaesthetic team in the preoperative assessment of obese patients in order to achieve appropriate risk stratification and optimise the care.

Shoulder arthroplasty following gastric bypass, do complications follow?

INTRODUCTION

Previous reports have shown an increased risk of complications after arthroplasty in the obese population. It remains unclear if gastric bypass surgery prior to shoulder arthroplasty modifies the complication and failure rate. The purpose of this study is to assess the complication and re-operation rates following shoulder arthroplasty in this population.

METHODS

Between 2002 and 2012, 39 shoulders with prior gastric bypass underwent shoulder arthroplasty (3 HA, 16 TSA, 20 RSA). The mean time from the gastric bypass to arthroplasty was 13 years (range, 0.7-32). Shoulders were followed for a minimum of two years (mean, 3.8 years) or until re-operation. Outcome measures included pain, range of motion, satisfaction, modified Neer ratings, and ASES scores.

RESULTS

Complications occurred in seven shoulders (18%), with five requiring re-operation. There was no common failure mechanism. Re-operations occurred for aseptic glenoid loosening, periprosthetic fracture, and unexplained pain. Those shoulders with complications were similar to those without in regard to age, sex, and BMI. Complications were more common following anatomic arthroplasty compared to reverse arthroplasty (5 vs 1, p = 0.06); however, complications were not improved compared to historical controls with morbid obesity. Overall, pain improved significantly from 4.8 pre-operatively to 2.3 postoperatively (p < 0.001). All groups, regardless of arthroplasty type, demonstrated significant improvements in forward elevation and external rotation.

CONCLUSION

Gastric bypass surgery prior to shoulder arthroplasty leads to clinical improvement in both pain and range of motion. Prior gastric bypass surgery does not result in a lower surgical complication rate compared to previously published reports in the morbidly obese population.

LEVEL OF EVIDENCE

Level 4, case series.

A Bundle Protocol to Reduce the Incidence of Periprosthetic Joint Infections After Total Joint Arthroplasty: A Single-Center Experience

BACKGROUND

Periprosthetic joint infection (PJI) represents a devastating complication of total hip arthroplasty (THA) or total knee arthroplasty (TKA). Modifiable patient risk factors as well as various intraoperative and postoperative variables have been associated with risk of PJI. In 2011, our institution formulated a "bundle" to optimize patient outcomes after THA and TKA. The purpose of this report is to describe the "bundle" protocol we implemented for primary THA and TKA patients and to analyze its impact on rates of PJI and readmission.

METHODS

Our bundle protocol for primary THA and TKA patients is conceptually organized about 3 chronological periods of patient care: preoperative, intraoperative, and postoperative. The institutional total joint database and electronic medical record were reviewed to identify all primary THAs and TKAs performed in the 2 years before and following implementation of the bundle. Rates of PJI and readmission were then calculated.

RESULTS

Thirteen of 908 (1.43%) TKAs performed before the bundle became infected compared to only 1 of 890 (0.11%) TKAs performed after bundle implementation (P = .0016). Ten of 641 (1.56%) THAs performed before the bundle became infected, which was not statistically different from the 4 of 675 (0.59%) THAs performed after the bundle that became infected (P = .09).

CONCLUSION

The bundle protocol we describe significantly reduced PJIs at our institution, which we attribute to patient selection, optimization of modifiable risk factors, and our perioperative protocol. We believe the bundle concept represents a systematic way to improve patient outcomes and increase value in total joint arthroplasty.