Bariatric surgery prior to total knee arthroplasty is not associated with lower risk of revision: a register-based study of 441 patients

Optimal timing of hip and knee arthroplasty after bariatric surgery: A systematic review

Background

Obesity is a risk factor for the development of osteoarthritis and contributes to the increasing demand for total joint arthroplasty (TJA). Because a lower preoperative weight decreases the risk of complications after TJA, and because bariatric surgery (BS) can reduce weight and comorbidity burden, orthopedic surgeons often recommend BS prior to TJA in patients with obesity. However, the optimal timing of TJA after BS in terms of complications, revisions and dislocations is unknown.

Methods

PubMed, Embase and Cochrane CENTRAL databases were systematically searched for any type of study reporting rates of complications, revisions and dislocations in patients who had TJA after BS. The included studies' quality was assessed using the Newcastle-Ottawa Scale.

Results

Out of the 16 studies eligible for review, eight registry-based retrospective studies of high to moderate quality compared different time periods between BS and TJA and overall their results suggest little differences in complication rates. The remaining eight retrospective studies evaluated only one time period and had moderate to poor quality. Overall, there were no clear differences in outcomes after TJA for the different time frames between BS and TJA.

Conclusion

The results of this systematic review suggest that there is limited and insufficient high-quality evidence to determine the optimal timing of TJA after BS in terms of the rates of complications, revisions and dislocations. Given this lack of evidence, timing of TJA after BS will have to be decided by weighing the individual patients' risk factors against the expected benefits of TJA.

Osteoarthritis in patients with obesity: The bariatric surgery impacts on its evolution

Obesity is one of the main modifiable risk factors for osteoarthritis (OA). Moreover, obesity is associated with greater pain intensity and functional limitation, but also with a significantly lower responder rate to intra-articular treatments. Consequently, an arthroplasty is indicated earlier and more frequently in patients with obesity. However, pain and functional symptoms improve slightly less after arthroplasty in patients with obesity, who display higher incidence of early and late complications following prosthetic surgery. Bariatric surgery (BS) has increased worldwide and is efficient to induce major and sustainable weight-loss. Importantly, BS significantly reduces pain and functional limitation in patients with symptomatic knee OA. Biomarkers analysis also revealed a decrease in catabolic factors and an increase in anabolic one after BS suggesting a structural protective effect in knee OA. Nevertheless, the impact of BS prior to arthroplasty remains unclear. BS seems to decrease short- and mid-term complications such as infections or thrombosis. However, BS does not appear to modify long-term complications rate, and may even increase it, especially revisions and infections. Although few studies have compared the symptomatic and functional outcomes of joint replacement with or without BS, these are not significantly improved by prior BS. Despite these heterogeneous results, medico-economic studies found that BS prior to arthroplasty was cost-effective. To conclude, BS could significantly reduce the symptoms of OA and potentially slow its progression, but appears more disappointing in preventing long-term complications of arthroplasties and improving their functional results.

Results from the Scandinavian Obesity Surgery Registry: A narrative review

In 2007, the Scandinavian Obesity Surgery Registry (SOReg) was started by the profession to monitor the results of bariatric surgery and to provide a high-quality database for research. In the end of August 2023, SOReg contains 88,379 patients (body mass index [BMI] 41.7 kg/m2 , 41.2 years, 77.1% females, gastric bypass 76.8%). In this narrative review, we demonstrate that preoperative weight loss is of value and that the laparoscopic double omega-loop technique is highly suitable for gastric bypass. Closing the mesenteric openings is, however, important. Swedish bariatric surgery has low mortality, and our results are comparative to those of other countries. Significant long-term improvements are found in common obesity-related diseases such as diabetes, hypertension, and sleep apnea. Furthermore, the risk for cardiac failure and major adverse cardiovascular events is significantly reduced. Pregnancy-related outcomes are also improved. Gastric bypass results in significant improvements in quality of life and seems to be cost saving. We have revealed that low socioeconomic status is associated with reduced chance of undergoing bariatric surgery and inferior outcomes. Of note, we have performed several randomized clinical trials within the registry database. In conclusion, high-quality national registry databases, such as SOReg, are important for maintaining high-quality care and present a platform for extensive research.

Bariatric surgery, osteoarthritis and arthroplasty of the hip and knee in Swedish Obese Subjects - up to 31 years follow-up of a controlled intervention study

OBJECTIVE

To study the long-term effect of obesity and bariatric surgery on incidences of osteoarthritis and arthroplasty of hip and knee.

DESIGN

Hazard ratios (HR) and incidence rates (IR) of osteoarthritis and arthroplasty of hip and knee were studied in the prospective, controlled, non-randomized Swedish Obese Subjects (SOS) study (bariatric surgery group, n = 2007; matched controls given usual obesity care, n = 2040) and the SOS reference cohort (n = 1135, general population). Osteoarthritis diagnosis and arthroplasty for osteoarthritis were captured from the National Swedish Patient Register. Median follow-up time was 21.2 (IQR 16.4-24.8), 22.9 (IQR 19.1-25.7), and 20.1 years (IQR 18.7-20.9) for the control group, surgery group and reference cohort, respectively.

RESULTS

The surgery group displayed lower incidence of hip osteoarthritis (IR 5.3, 95% CI 4.7-6.1) compared to controls (IR 6.6, 95% CI 5.9-7.5, adjHR 0.83, 95% CI 0.69-1.00) but similar incidence of hip arthroplasty. Similar incidence of knee osteoarthritis was observed in the surgery group and controls, but knee arthroplasty was more common in the surgery group (IR 7.4, 95% CI 6.6-8.2 and 5.6, 95% CI 4.9-6.4, adjHR 1.45, 95% CI 1.22-1.74). The reference cohort displayed lower incidences of osteoarthritis and arthroplasty of hip and knee compared with the surgery group and controls.

CONCLUSION

Bariatric surgery did not normalize the increased risk of knee and hip osteoarthritis in patients with obesity but was associated with an increased incidence of knee arthroplasty compared to the control group. With the limitations inherent to the present data, additional studies are needed to confirm these results.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01479452.

Information and BMI limits for patients with obesity eligible for knee arthroplasty: the Swedish surgeons' perspective from a nationwide cross-sectional study

BACKGROUND

In the past decades, the incidence of obesity has increased worldwide. This disease is often accompanied with several comorbidities and therefore, surgeons and anesthesiologists should be prepared to provide optimal management for these patients. The aim of this descriptive cross-sectional study was to map the criteria and routines that are used by Swedish knee arthroplasty surgeons today when considering patients with obesity for knee arthroplasty.

METHODS

A survey including 21 items was created and sent to all the Swedish centers performing knee arthroplasty. The survey included questions about the surgeons' experience, hospital routines of preoperative information given and the surgeons' individual assessment of patients with obesity that candidates for knee arthroplasty. Descriptive statistics were used to present the data.

RESULTS

A total of 203 (64%) knee surgeons responded to the questionnaire. Almost 90% of the surgeons claimed to inform their patients with obesity that obesity has been associated with an increased risk of complications after knee arthroplasty. Seventy-nine percent reported that they had an upper BMI limit to perform knee arthroplasty, a larger proportion of the private centers had a BMI limit compared to public centers. The majority of the centers had an upper BMI limit of 35.

CONCLUSION

The majority of the knee arthroplasty surgeons in Sweden inform their patients with obesity regarding risks associated with knee arthroplasty. Most centers that perform knee arthroplasties in Sweden have an upper BMI limit.

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.

Pain, Function, and Satisfaction After Total Knee Arthroplasty, with or Without Bariatric Surgery

BACKGROUND

The impact of obesity on patient-reported outcome (PRO) after total knee arthroplasty (TKA) surgery has demonstrated varying results. We evaluated knee pain, Activity in Daily Life function (ADL), and satisfaction after TKA surgery in patients with and without prior bariatric surgery (BS).

METHODS

Scandinavian Obesity Surgery Registry (SOReg) and the Swedish Knee Arthroplasty Register (SKAR) were used to identify patients operated on with primary TKA for osteoarthritis (OA) between 2009 and 2019 that had a BS within 2 years before the TKA (BS group). These patients were compared to patients with TKA without prior BS (no BS group). The patients filled in the Knee injury and Osteoarthritis Outcome Score (KOOS) preoperatively and one year postoperatively as well as satisfaction with the surgery one year postoperatively. Multiple linear regression analysis was used to evaluate 1-year postoperative KOOS pain and ADL function between the 2 groups. Adjustments were made for sex, age, and preoperative KOOS pain and ADL function respectively.

RESULTS

Forty-four patients were included in the BS group and 3,525 patients in the no BS group. We found no statistically or clinically significant difference in one-year postoperative KOOS pain and ADL function between the BS group and the no BS group. The majority of the patients in both groups were classified as satisfied or very satisfied one year postoperatively to the TKA.

CONCLUSIONS

Our results indicate that patients without BS prior to the TKA gain similar 1-year outcome in pain, ADL function and satisfaction as patients with prior BS.

EFORT recommendations for off-label use, mix & match and mismatch in hip and knee arthroplasty

Off-label use is frequently practiced in primary and revision arthroplasty, as there may be indications for the application of implants for purposes outside the one the manufacturers intended.

Under certain circumstances, patients may benefit from selective application of mix & match. This can refer to primary hip arthroplasty (if evidence suggests that the combination of devices from different manufacturers has superior results) and revision hip or knee arthroplasty (when the exchange of one component only is necessary and the invasiveness of surgery can be reduced).

Within the EFORT ‘Implant and Patient Safety Initiative’, evidence- and consensus-based recommendations have been developed for the safe application of off-label use and mix & match in primary as well as revision hip and knee arthroplasty.

Prior to the application of a medical device for hip or knee arthroplasty off-label and within a mix & match situation, surgeons should balance the risks and benefits to the patient, obtain informed consent, and document the decision process appropriately.

Nevertheless, it is crucial for surgeons to only combine implants that are compatible. Mismatch of components, where their sizes or connections do not fit, may have catastrophic effects and is a surgical mistake.

Surgeons must be fully aware of the features of the components that they use in off-label indications or during mix & match applications, must be appropriately trained and must audit their results.

Considering the frequent practice of off-label and mix & match as well as the potential medico-legal issues, further research is necessary to obtain more data about the appropriate indications and outcomes for those procedures.

Cite this article: EFORT Open Rev 2021;6:982-1005. DOI: 10.1302/2058-5241.6.210080

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.