Surgical Risks and Costs of Care are Greater in Patients Who Are Super Obese and Undergoing THA

Beyond the Scale: Exploring Parathyroidectomy Outcomes in Super Obesity (BMI ≥ 50)

INTRODUCTION

Super obesity (body mass index ≥50) poses unique surgical challenges; however, its impact on parathyroidectomy outcomes is unexplored. This study examines surgical risks, recovery, and success rates in super-obese patients undergoing parathyroidectomy.

METHODS

A retrospective cohort of 3206 patients (84 super-obese, 3076 nonsuper-obese) who underwent parathyroidectomy from 2000 to 2024 was analyzed. Outcomes included complications, cure rates, and preoperative and/or postoperative laboratory values.

RESULTS

Super-obese patients were younger (54.7 ± 1.4 versus 58.8 ± 0.3 years, P = 0.01) with lower preoperative vitamin D levels (26.7 ± 2.0 versus 32.7 ± 0.3 ng/mL, P < 0.001). They had higher rates of double adenomas (18.1% versus 10.5%, P = 0.03), malignancies (3.6% versus 0.1%, P < 0.001), and inpatient stays (11.5% versus 3.5%, P = 0.03). Complication rates and cure rates were similar between groups.

CONCLUSIONS

Parathyroidectomy is safe in super-obese patients at high-volume centers, although pathologies are unique and inpatient admissions are more common.

Effect of BMI on the risk of postoperative complications following total hip arthroplasty

Aims

While obesity is associated with an increased risk of complications after total hip arthroplasty (THA), the relationship between BMI and the risk of early postoperative complications has not been fully characterized. This study sought to describe the relationship between BMI and the risk of early postoperative complications, including periprosthetic joint infection (PJI), and composite surgical and composite medical complications.

Methods

Primary, elective THAs performed from 1 October 2015 to 31 December 2021 were identified using the Premier Healthcare Database. The study's primary outcome was the diagnosis of PJI within 90 days of THA. Using BMI as a continuous variable, logistic regression was used to develop restricted cubic splines (RCSs) to determine the impact of BMI on PJI risk. Bootstrap simulation was used to identify an inflection point in the final RCS model. The same technique was used to characterize the effects of BMI on composite medical and surgical complications.

Results

We found that PJI risk increased exponentially beyond a BMI threshold of 37.4 kg/m2. Relative to this threshold, patients with a BMI of 40 or 50 kg/m2 were at a 1.22-fold and 2.55-fold increased risk of developing PJI, respectively. Surgical complications increased at a BMI of 32 kg/m2 and medical complications increased at a BMI of 39 kg/m2. Relative to these cut points, patients with a BMI of 50 kg/m2 were at a 1.36-fold and 2.07-fold increased risk of developing medical and surgical complications, respectively.

Conclusion

The results of this study indicate a non-linear relationship between patient BMI and early postoperative risk of PJI, composite medical complications, and composite surgical complications following THA. The identified cut points with associated odds ratios can serve as tools to help risk-stratify and counsel patients seeking primary THA.

Increased Body Mass Index Is Associated With Increased Cost for Primary Total Hip Arthroplasty Irrespective of Complications or Readmissions

BACKGROUND

Surgeons participating in alternative payment models may encounter financial disincentives in caring for patients whose care requires higher costs for the treatment facility. While smaller studies have shown a positive relationship between body mass index (BMI) and cost in total hip arthroplasty (THA), this question has yet to be examined using data in a nationally representative dataset. We sought to leverage a national dataset to assess the relationship between BMI and cost in THA.

METHODS

We queried a health care dataset from 2016 to 2022 to identify primary THAs using Current Procedural Terminology and International Classification of Disease-Procedure Coding System codes (27130, 0SR90xx, and 0SRB0xx) with a corresponding osteoarthritis diagnosis (International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM): M16). Patient demographics, characteristics, and cost variables were extracted directly from the dataset. Cost was defined by supplies, labor, and equipment and assessed over a 90-day period starting with the index surgical encounter. A multivariate generalized linear model estimated costs across eight BMI categories (World Health Organization BMI categories, with BMI > 40 patients grouped into BMI 40 to 45, BMI 45 to 50, and BMI > 50). A linear regression model assessed the effect of BMI on costs. Both models controlled for age, sex, payer, race, the Elixhauser comorbidity index, and ethnicity.

RESULTS

This study examined 10,366 primary THAs completed from 2016 to 2022. The mean BMI was 30.0 (standard error [SE] ± 0.1), the mean index cost was $14,632 (SE 52.9), and the mean 90-day cost was $16,527 (SE 145.4). Index and 90-day costs were lowest in the BMI 25 to 30 cohort ($14,344 and $15,865) and highest for the BMI >50 cohort ($17,503 and $28,281), respectively. On multivariate analyses, index and 90-day cost increased by $23 and $69, respectively, for every one-point increase in BMI (P < 0.001).

CONCLUSIONS

Results from this nationally representative dataset demonstrate that increasing BMI is associated with increased index and 90-day costs for THA. This information may be useful to stakeholders in the development of alternative payment models.

[Risk and complication profiles of orthogeriatric patients in elective hip and knee joint replacement]

BACKGROUND

The care of geriatric patients undergoing elective orthopedic surgery is becoming increasingly more important due to demographic trends. Compared to geriatric traumatology, however, there are still no established orthogeriatric care models in Germany and therefore hardly any scientific data. The aim of this study was to describe the risk and complication profiles in older patients with elective hip and knee replacements.

METHODS

In a prospective study data were collected from orthogeriatric patients with indications for elective hip and knee replacement surgery who fulfilled defined inclusion and exclusion criteria between January 2021 and August 2023 in the orthopedic department of a German university hospital for the descriptive analysis of risk and complication profiles. In addition to a preoperative and perioperative data analysis, a follow-up was conducted 4-6 weeks and 3 months postoperatively.

RESULTS

The surgical risk profile of the patient population analyzed was characterized by advanced age (78.4 ± 4.8 years), preobesity/obesity (76%), multimorbidity (7.4 ± 3.1 comorbidities), polypharmacy (7.5 ± 3.8 medications), immobility (short physical performance battery 7.1 ± 2.6), prefrailty/frailty (87%), frequent anticoagulation (22%) and a high number of potentially inappropriate medications (64%). Complication events mainly occurred within the first 7 days postoperatively and 90% of the events within this recording period were minor complications. The overall complication rate significantly decreased in the follow-up period.

CONCLUSION

Due to the high risk and complication profiles the routine use of orthogeriatric co-management models for elective orthopedic surgery should be considered in the future.

A survey of Scottish Committee for Orthopaedics and Trauma members on lower limb joint replacement practices in morbidly obese patients

Background

Scotland has one of the highest rates of obesity in the developed world which increases risk of lower limb osteoarthritis resulting in total joint arthroplasty (TJA). This paper aimed to investigate (1) current practice of orthopaedic consultants in Scotland in managing end-stage hip and knee osteoarthritis in obese patients, (2) adherence to National guidelines, and (3) understanding of complication risks in lower limb TJA for BMI≥40.

Methods

A 15-question online survey was sent to all active members of Scottish Committee for Orthopaedics and Trauma (SCOT) between February and March 2023 to understand the current practices for managing obese patients with lower limb arthritis requiring joint replacement surgery.

Results

The survey received 62 responses from members of SCOT. The experience ranges from 1 to 44 years (mean 15 years) at consultant level. 61 % of respondents were aware of the SCOT National Guidelines for lower limb TJA in obese patients. 72 % would offer TJA to patients with a BMI>40.35 % would get a second opinion and 22 % discuss these cases in a multidisciplinary team meeting. 71 % were aware of the local weight management guidelines. 77 % quoted risk of deep infection to be between 1 and 30 %, and 40 % quoted risk of amputation between .002 % and 10 % in morbidly obese patients.

Conclusion

Surgical management of obese patients with lower limb osteoarthritis in Scotland is variable. A standardised approach would be beneficial in obtaining informed consent.

Body Mass Index and the Risk of Postoperative Complications After Total Knee Arthroplasty

INTRODUCTION

Given the growing prevalence of obesity, it is crucial to understand the effect of obesity on complications after total knee arthroplasty (TKA). This study aims to assess the relationship between body mass index (BMI) and postoperative periprosthetic joint infection (PJI), medical complications, and surgical complications after TKA.

METHODS

The Premier Healthcare Database was used to identify all primary elective TKAs between 2016 and 2021. The primary outcome was risk of PJI within 90 days of surgery. Using logistic regression, restricted cubic splines were generated to assess the relationship between BMI as a continuous variable and PJI risk. Bootstrap simulation was then done to identify a BMI inflection point on the final restricted cubic spline model past which the risk of PJI increased. The relationship between BMI and composite 90-day medical and surgical complications was also assessed.

RESULTS

A direct relationship was observed between increasing BMI and increasing risk of PJI with a BMI changepoint of 31 kg/m 2 identified as being associated with increased risk. Above a BMI of 31 kg/m 2 , there was an average relative risk increase of PJI of 13.6% for every unit BMI. This relative risk per unit BMI increased from 5.8% for BMI 31 to 39 to 11.5% between BMI 40 and 49 kg/m 2 , and 21.3% for BMIs ≥50 kg/m 2 . Similarly, a direct relationship was also found between increasing BMI and both medical and surgical complications with BMI changepoints of 34 and 32 kg/m 2 identified, respectively.

DISCUSSION

Obese patients with a BMI >31 kg/m 2 were at increased risk of PJI. Although the relative risk increase was small per unit BMI above 31 kg/m 2 , the cumulative increase in risk may be marked for patients with higher BMIs.

CONCLUSION

These data should be used to inform discussions that involve shared decision making between patients and surgeons who weigh the risks and benefits of surgery.

Should Body Mass Index Be Considered a Hard Stop for Total Joint Replacement?: An Ethical Dilemma

Total joint arthroplasty (TJA) is one of the most common surgeries performed in the United States and is a durable and effective option in managing osteoarthritis of the hip and knee. Recent research regarding the procedure has focused on preoperative optimization and weight loss in particular. Obesity has been shown in prior studies to increase risks associated with TJA, and, as a result, debate has focused on whether a body mass index (BMI) cutoff is a prudent tool for preoperative optimization. This article discusses the ethical dilemma of instituting a BMI cutoff and reviews current literature regarding the topic.

Prior Bariatric Surgery Is Associated With Improved Total Hip Arthroplasty Outcomes in Patients Who Have Obesity: A National Cohort Study With 6 Years of Follow-Up

BACKGROUND

Obesity is a risk factor for end-stage hip osteoarthritis. While total hip arthroplasty (THA) is commonly performed to reduce pain and improve function associated with osteoarthritis, obesity has been associated with an increased risk of complications after THA. Although bariatric surgery may also be utilized to reduce weight, the impact of bariatric surgery on THA outcomes remains inadequately understood.

METHODS

This retrospective cohort analysis utilized multicenter electronic medical record data ranging from 2003 to 2023. Patients who have obesity who underwent THA were stratified based on prior bariatric surgery. The final bariatric cohort comprised 451 patients after propensity score matching. Complication rates and revision risks were compared between cohorts at 6, 24, and 72 months. Additional analysis stratified patients by interval between bariatric surgery and THA.

RESULTS

At 6-month follow-up, the bariatric cohort had significantly lower risks of surgical site infection, wound dehiscence, and deep vein thrombosis (DVT). At 24 months, the bariatric cohort had a lower risk of DVT. At 72-month follow-up, the bariatric cohort had reduced rates of revision, mortality, cardiac morbidity, and Clavien-Dindo grade IV complications.

CONCLUSIONS

Obese patients who underwent bariatric surgery prior to THA experienced reduced medical complications at all time points and reduced rates of revision at 72 months relative to a matched cohort who did not undergo bariatric surgery.

Sleeve gastrectomy prior to primary total hip and total knee arthroplasty is associated with increased risk of early complications

Aims

The purpose of this study was to determine the association between prior sleeve gastrectomy in patients undergoing primary total hip and knee arthroplasty, and 90-day complications, incidence of revision arthroplasty, and patient-reported outcome scores at final follow-up.

Methods

This is a retrospective, single-centre analysis. Patients undergoing primary hip or knee arthroplasty with a prior sleeve gastrectomy were eligible for inclusion (n = 80 patients). A morbidly obese control group was established from the same institutional registry using a 1:2 match, for cases:controls with arthroplasty based on propensity score using age, sex, pre-sleeve gastrectomy BMI, Current Procedural Terminology code to identify anatomical location, and presurgical haemoglobin A1C. Outcomes included 90-day complications, incidence of revision arthroplasty, and patient-reported outcome scores at final follow-up. Multivariable logistic regressions evaluated associations of underlying preoperative demographic and treatment characteristics with outcomes.

Results

Complications within 90 days of surgery were increased in the sleeve gastrectomy group relative to the obese control group after controlling for underlying preoperative demographic characteristics (odds ratio (OR) 4.00 (95% CI 1.14 to 13.9); p = 0.030). Postoperative revisions were similar in the sleeve gastrectomy group relative to the obese control group after controlling for underlying preoperative demographic characteristics (OR 17.8 (95% CI 0.64 to 494.3); p = 0.090). Patient-Reported Outcomes Measurement Information System (PROMIS) depression decreased by a greater amount from pre- to postoperative in the obese controls relative to the sleeve gastrectomy group (OR 4.04 (95% CI 0.06 to 8.02); p = 0.047). PROMIS pain interference and physical function change from pre- to postoperative was not associated with sleeve gastrectomy status.

Conclusion

We found a higher rate of complications at 90 days in patients who underwent sleeve gastrectomy prior to primary hip or knee arthroplasty relative to a matched, obese control population. Prosthetic revision rates were similar between the two groups, while improvements in PROMIS depression scores were larger in the obese cohort. This study suggests that sleeve gastrectomy to achieve preoperative weight loss prior to arthroplasty surgery may not mitigate early complication risks in obese patient populations.

Obesity and Primary Total Hip Arthroplasty: The Absolute versus Relative Risk of Periprosthetic Joint Infection at 15 Years

BACKGROUND

To make an informed decision about total hip arthroplasty (THA), surgeons and patients need to understand the absolute and relative risks of periprosthetic joint infection (PJI). We sought to evaluate the long-term risk of PJI following primary THA stratified by body mass index (BMI) and PJI-related risk factors.

METHODS

We identified 21,550 primary THAs performed from 2000 to 2021 at a single institution. Patients were stratified as having 0, 1, or ≥ 2 PJI risk factors (diabetes, chronic kidney disease, nonprimary osteoarthritis, immunosuppression, or active smoking) and into BMI categories. The 15-year cumulative risk of PJI was evaluated by BMI and PJI risk factors.

RESULTS

For the entire cohort, the 15-year absolute risk of PJI was 2%. For patients who did not have PJI risk factors, the absolute risk of PJI at 15 years was 1% in normal weight, 2% in class III obesity, and 4% in class IV obesity. Patients who had class III and IV obesity had a 3-times and 9-times higher relative risk of PJI, respectively (P = .03, P < .001). Among patients who had ≥ 2 PJI risk factors, the absolute risk of PJI at 15 years was 2% in normal weight, 4% in class III obesity, and 18% in class IV obesity.

CONCLUSIONS

Healthy patients who had class III and IV obesity had a 3-times and 9-times increased risk of PJI at 15 years relative to normal weight patients. However, the absolute risk of PJI at 15 years was 2 and 4%, respectively. Given emerging data questioning whether BMI modification decreases PJI risk, surgeons and patients must consider both a 3-times to 9-times increased relative risk of PJI and a 2 to 4% absolute risk of PJI at 15 years for healthy patients who had a BMI ≥ 40.

LEVEL OF EVIDENCE

IV.

Preoperative weight loss before total hip arthroplasty negatively impacts postoperative outcomes

BACKGROUND

Obesity adversely impacts outcomes of total hip arthroplasty (THA), leading surgeons to impose body mass index cutoffs for patient eligibility and encourage preoperative weight loss. This study aimed to determine if preoperative weight loss impacts outcomes of THA in the general patient population and if it mitigates poor outcomes in obese patients.

METHODS

Patients who underwent THA from 2013-2020 were identified in the National Surgical Quality Improvement Program (NSQIP) database. Patients were stratified by weight loss of >10% of body weight over the preceding 6 months. We used multivariable linear and logistic regression models, adjusted for age, sex, race/ethnicity, and comorbidities, to examine the effect of significant preoperative weight loss on 30-day outcomes after THA in the general and obese patient populations.

RESULTS

In the overall population, patients who lost significant weight preoperatively had significantly increased length of stay, were more likely to have a non-home discharge, return to the operating room, or be readmitted, and were more likely to experience numerous medical complications. In the obese population, patients who lost significant weight preoperatively had significantly increased length of stay and were more likely to require a transfusion or experience any medical complication.

DISCUSSION

Rapid significant preoperative weight loss is not associated with improved postoperative outcomes after THA in the obese population and is associated with worse outcomes in the general population. Arthroplasty surgeons should balance these risks with the risks of obesity when advising patients about preoperative weight loss prior to THA.

LEVEL OF EVIDENCE

III.

Impact of a dietitian-led very low calorie diet clinic on perioperative risk for patients with obesity awaiting elective, non-bariatric surgery: A retrospective cohort study

BACKGROUND

Despite a lack of evidence that intentional weight loss reduces the risk of postoperative complications, adults with obesity are commonly asked to lose weight before elective surgery. We hypothesized that patients undertaking dietitian-led preoperative, very low calorie diet treatment could reduce perioperative surgery risks, as per validated risk scoring systems. The purpose of this study was to measure the impact of a dietitian-led preoperative very low calorie diet clinic on the American Society of Anesthesiologists physical status scores and National Surgical Quality Improvement Program Surgical Risk Calculator scores for patients with obesity awaiting non-bariatric elective surgery.

METHODS

This retrospective cohort study included patients referred to the preoperative dietitian-led very low calorie diet clinic before elective surgical procedures over a 2-year-9-month period. The dietitian prescribed individualized, very low calorie diet-based treatment. Primary outcomes were changes in the American Society of Anesthesiologists and Surgical Risk Calculator scores from pretreatment until surgery.

RESULTS

A total of 141 eligible participants (48 ± 13.4 years, 76% women, body mass index 41.7 ± 6.3 kg/m2) demonstrated clinically significant weight loss (mean 7.1 ± 6.1kg, 5.2% body weight, P < .001). Median treatment duration was 13 weeks (interquartile range 6.2-19.2 weeks). Five participants (3.5%) avoided surgery due to weight loss-related improvements in their condition. American Society of Anesthesiologists scores improved for 16% (n = 22/141) of participants. Overall, the median surgical risk calculator estimated risk of 'serious' and 'any' postoperative complication reduced from 4.8% to 3.9% (P < .001) and 6% to 5.1% (P < .001), respectively. Reduction in all Surgical Risk Calculator scores occurred, including surgical site infection, re-admission, and cardiac events (P < .05).

CONCLUSION

The dietitian-led preoperative, very low calorie diet clinic improved American Society of Anesthesiologists and Surgical Risk Calculator scores for non-bariatric elective surgery patients with obesity. Randomized controlled trials comparing this approach with a control group are warranted.

Does Body Mass Index (BMI) Affect the Reconstruction of Biomechanical Parameters in Patients Undergoing Total Hip Replacement (THR) through the Direct Anterior Approach (DAA)?

OBJECTIVE

Direct anterior approach total hip replacement (DAA-THR) is gaining increased interest due to its tissue-sparing nature and rapid recovery. Obesity has been shown to be a significant parameter influencing cup positioning in DAA-THR. It was the intention of this retrospective study to examine how obesity would influence the restoration of native hip biomechanical parameters during DAA-THR.

MATERIALS AND METHODS

A total of 74 patients from a high-volume university orthopedic center after unilateral DAA-THA were included. Patients were retrospectively allocated to a study group (BMI > 30 kg/m2) and a control group (BMI < 30 kg/m2). Furthermore, propensity-score matching for baseline parameters was performed, leaving 30 patients in each group. Biomechanical parameters of the hip (i.e., femoral offset (FO), abductor lever arm (ABL), acetabular offset (AO), center of rotation (COR), stem alignment (SA), body weight lever arm (BWL), cup inclination (CI), and leg length discrepancy (LLD) were evaluated on standardized plain radiographs, and parameters were compared to the native contralateral hip.

RESULTS

Mean BMI in the study group was 35.07 ± 5.13 kg/m2 and 25.43 ± 2.64 kg/m2 in the control group. There was a significant decrease of the ABL only in the study cohort (p = 0.01). CI and SA did not differ between both cohorts. FO was slightly increased compared to the native hip in both groups. There was a marginally higher but non-significant proportion of improper FO restoration in the study group (19 vs. 16 patients, p = 0.60).

CONCLUSIONS

Obesity, as quantified by BMI, only has a limited impact on the adequate reconstruction of native biomechanical parameters of the hip during DAA-THR. ABL was the only parameter to be significantly decreased in the overweight patients after DAA-THR. Therefore, special care should be taken on proper acetabular reaming and consequent seating of the cup in the obese patient to avoid excessive lateral positioning.

Nutrition in Surgery: An Orthopaedic Perspective

➤ Malnutrition is common among subsets of patients undergoing orthopaedic surgery and is associated with an increased risk of postoperative complications.➤ Serum proteins, in particular, albumin, may be used in the evaluation of nutritional status.➤ Anthropometric measurements and surveys also play a role in the evaluation of nutritional status.➤ Increased energy and nutrient requirements due to surgical procedures necessitate increased caloric and protein intake in the perioperative period, which may be achieved through diet or supplementation.➤ Evidence supports the use of protein-calorie, amino acid, and immunonutrition supplements. Vitamin D supplementation is an area of further consideration.➤ Diet restriction, activity alterations, pharmacotherapy, and bariatric surgery are all safe, effective approaches to weight loss, although the optimal timing and magnitude of preoperative weight loss require further investigation.

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.

Are Patient Outcomes Affected by Surgeon Experience With Total Hip Arthroplasty in Morbidly Obese Patients?

Background

Surgeons with high volume (HV) of total hip arthroplasty (THA) have seen better outcomes than low volume (LV) surgeons. However, literature regarding surgeon volume and outcomes in morbidly obese THA patients is scarce. This study examines the association between surgeon volume with THA in morbidly obese patients (body mass index ≥40) and their clinical outcomes.

Methods

We retrospectively reviewed all morbidly obese patients who underwent primary THA at our institution between March 2012 and July 2020 with 2 years of follow-up. Clinical outcomes were compared between the HV (HVa, top quartile of surgeons with the highest overall yearly THA volume) and LV (LVa) surgeons. Similar analysis was run comparing HV of morbidly obese THA (HVo, top quartile of surgeons with the highest yearly morbidly obese THA volume) and LV of morbidly obese THA (LVo) surgeons.

Results

Six hundred and forty-three patients and 33 surgeons were included. HVa surgeons had significantly shorter length of stay and increased home discharge. HVa and HVo surgeons had significantly shorter operative times. There were no significant differences in overall 90-day major and minor complications or clinical differences in patient-reported outcomes. Revision rates and freedom from revisions did not differ between groups at 2-year follow-up.

Conclusions

HVa surgeons had significantly lower length of stay and operative times and increased discharge to home. There was no significant decrease in complications or revisions in either comparison model. Complications, revision rates, and patient satisfaction in morbidly obese patients who undergo THA may be independent of surgeon volume.

The influence of obesity on the complications and outcomes of shoulder arthroplasty: A systematic review and meta-analysis

OBJECTIVE

This systematic review aimed to determine whether obesity has a negative impact on the incidence of complications and functional scores of all types of shoulder arthroplasty.

METHODS

Electronic databases such as PubMed, Embase, Web of Science, and Cochrane were systematically searched for publications concerning obesity and shoulder arthroplasty. The Newcastle-Ottawa scale criteria were used to evaluate the study's quality. A total of 15 studies were identified involving total shoulder arthroplasty, reverse total shoulder arthroplasty, or hemiarthroplasty. The studies com- paring the outcome of shoulder arthroplasty in different weight groups were conducted after the search of related literature and grouped according to different weights and compared with each other. Counted data used odds ratio value and its 95% CI for data analysis, and measurement data used weighted mean difference and its 95% CI for statistical analysis.

RESULTS

The remaining 12 articles met the inclusion criteria and were included in this review. Any infection was reported in 6 studies, including 197 013 patients. Infections were more likely to occur in obese patients, with an odds ratio of 3.38 (95% CI, 2.28-5.02). The operation time of overweight patients (body mass index >25 kg/m2) was significantly longer than that of normal-weight patients (odds ratio, 6.90; 95% CI, 3.79-10.00). The venous thromboembolism was more likely to occur in obese patients (odds ratio, 3.39; 95% CI, 3.6- 4.28). In addition, there was no significant difference in the dislocation rate and revision rate of prostheses among the groups. Patients who undergo shoulder arthroplasty could obtain a good American Shoulder and Elbow Surgeons score (Mean Difference [MD], 1.87; 95% CI, -2.08 to 5.82), regardless of their body mass index.

CONCLUSION

Obesity had a negative impact on the prognosis of patients treated with shoulder arthroplasty. Additionally, obese patients require longer surgical times than normal-weight patients, although all patients can attain positive functional outcomes.

LEVEL OF EVIDENCE

Level III, Therapeutic Study.

Patient Characteristics, Length of Stay, Cost of Care, and Complications in Super-Obese Patients Undergoing Total Hip Arthroplasty: A National Database Study

BACKGROUND

The purpose of this study was to compare postoperative complication rates in super-obese (SO) patients with a body mass index (BMI) ≥ 50 kg/m2 undergoing total hip arthroplasty (THA) versus non-super-obese (NSO) patients undergoing THA.

METHODS

In this retrospective study using the National Inpatient Sample (NIS) database, 1,646 cases of THA in SO (BMI ≥ 50 kg/m2) patients were reviewed. We used International Classification of Diseases (ICD)-10 codes to assess postoperative variables including length of stay, cost of care (cost of inpatient hospitalization), and medical and surgical complications among SO patients undergoing THA compared to NSO patients before being discharged.

RESULTS

A comparison of demographic variables showed there were more women in both groups and nearly 17.2% of SO patients were diabetic patients, 11.1% of SO patients were tobacco users, and 74.8% of the SO patients were whites (African American, 15.1%; Hispanic, 2.9%). The mean length of stay was 3.43 days in the SO group and 2.32 days in the NSO group, and this difference was statistically significant. The cost of care was $79,784.64 for the SO group, which was significantly higher than $66,821.75 for the NSO group. The SO group also showed higher odds of developing medical complications such as anemia (odds ratio [OR], 1.555; 95% confidence interval [CI], 1.395-1.734; p < 0.001), acute renal failure (OR, 3.375; 95% CI, 2.816-4.045; p < 0.001), pneumonia (OR, 2.319; 95% CI, 1.241-4.331; p = 0.014), and need for blood transfusion (OR, 1.596; 95% CI, 1.289-1.975; p < 0.001). The SO patients also showed a higher risk of several postoperative surgical complications such as periprosthetic fractures, infection, and wound dehiscence.

CONCLUSIONS

Postoperative complication rates in SO patients were higher than those in the NSO group. Length of stay and cost of care were higher, whereas the mean age was lower for the SO group. Therefore, THA in SO patients should be undertaken only after careful consideration and preferably in a tertiary facility capable of handling all medical and surgical in-hospital complications.

Total Hip and Knee Arthroplasty Surgery in the Morbidly Obese Patient: A Critical Analysis Review

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Obesity, defined as body mass index (BMI) ≥30, is a serious public health concern associated with an increased incidence of stroke, diabetes, mental illness, and cardiovascular disease resulting in numerous preventable deaths yearly.

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From 1999 through 2018, the age-adjusted prevalence of morbid obesity (BMI ≥40) in US adults aged 20 years and older has risen steadily from 4.7% to 9.2%, with other estimates showing that most of the patients undergoing hip and knee replacement by 2029 will be obese (BMI ≥30) or morbidly obese (BMI ≥40).

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In patients undergoing total joint arthroplasty (TJA), morbid obesity (BMI ≥40) is associated with an increased risk of perioperative complications, including prosthetic joint infection and mechanical failure necessitating aseptic revision.

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The current literature on the role that bariatric weight loss surgery before TJA has on improving surgical outcomes is split and referral to a bariatric surgeon should be a shared-decision between patient and surgeon on a case-by-case basis.

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Despite the increased risk profile of TJA in the morbidly obese cohort, these patients consistently show improvement in pain and physical function postoperatively that should be considered when deciding for or against surgery.

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

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

[Preoperative screening for risk factors]

The demographic change and continuously improving healthcare lead to increasing numbers of older, comorbid patients in elective orthopedic surgery. Perioperative risk assessment is crucial for patient counseling and preoperative planning. Risk factors, such as heart failure, chronic obstructive pulmonary disease, peripheral arterial occlusive disease, anemia, malnutrition, obesity, smoking and insufficiently controlled diabetes mellitus are common in patients undergoing elective orthopedic surgery. A thorough and early screening not only enables the individual assessment of the risk profile but in an elective setting also enables the chance for modification of certain risk factors in order to reduce the individual perioperative risk. Meanwhile, recommendations regarding risk stratification and adjustment of modifiable risk factors are included in national guidelines on the indications for elective total hip arthroplasty.

Projected Prevalence of Obesity in Primary Total Knee Arthroplasty: How Big Will the Problem Get?

BACKGROUND

Obesity is a well-established risk factor for complications following primary total knee arthroplasty (TKA). The purpose of this study is to utilize 3 national databases to develop projections of obesity within the general population and primary TKA patients in the United States through 2029.

METHODS

Data from the National Surgical Quality Improvement Program (NSQIP), the Behavior Risk Factor Surveillance System (BRFSS), and the National Health and Nutrition Examination Survey were queried for years 1999-2019. Current Procedural Terminology code 27447 was used to identify primary TKA patients in NSQIP. Individuals were categorized according to body mass index (kg/m²) by year: normal weight (≤24.9); overweight (25.0-29.9); obese (30.0-39.9); and morbidly obese (≥40). Multinomial logistic regression was used to project categorical body mass index data for years 2020-2029.

RESULTS

A total of 8,372,221 individuals were included (7,986,414 BRFSS, 385,807 NSQIP TKA). From 2011 to 2019, the prevalence of normal weight and overweight individuals declined in the general population (BRFSS) and in primary TKA. Prevalence of obese/morbidly obese individuals increased in the general population from 31% to 36% and in primary TKA from 60% to 64%. Projection models estimate that by 2029, 46% of the general population will be obese/morbidly obese and 69% of primary TKA will be obese/morbidly obese.

CONCLUSION

By 2029, we estimate ≥69% of primary TKA to be obese/morbidly obese. Increased resources dedicated to care pathways and research focused on improving outcomes in obese arthroplasty patients will be necessary as this population continues to grow.

LEVEL OF EVIDENCE

Level III, Retrospective Cohort Study.

What is the Impact of Body Mass Index Cutoffs on Total Knee Arthroplasty Complications?

BACKGROUND

Body mass index (BMI) cutoffs are commonly used to decide whether to offer obese patients elective total knee arthroplasty (TKA). However, weight loss goals may be unachievable for many patients who are consequentially denied complication-free surgery. The purpose of this study was to assess the impact of different BMI cutoffs on the rates of complication-free surgery after TKA.

METHODS

Patients undergoing elective, primary TKA from 2015 to 2018 were identified in the American College of Surgeons National Surgical Quality Improvement Program database using Common Procedural Terminology code 27447. The BMI and rates of any thirty-day complication were collected. BMI cutoffs of 30, 35, 40, 45, and 50 kg/m² were applied to model the incidence of complications if TKA would have been allowed or denied based on the BMI.

RESULTS

A total of 314,719 patients underwent TKA, and 46,386 (14.7%) had a BMI ≥40 kg/m². With a BMI cutoff of 40 kg/m², 268,333 (85.3%) patients would have undergone TKA. A total of 282,552 (94.8%) would experience complication-free surgery, and 17.3% of all complications would be prevented. TKA would proceed for 309,479 (98.3%) patients at a BMI cutoff of 50 kg/m². A total of 293,108 (94.7%) would not experience a complication, and 2.8% of complications would be prevented. A BMI cutoff of 35 kg/m² would prevent 36.6% of all complications while allowing 94.8% of complication-free surgeries to proceed.

CONCLUSION

Lower BMI cutoffs can reduce complications, but will limit access to complication-free TKA for many patients. These data do not indicate TKA should be performed without consideration of risks from obesity; however, a holistic assessment and shared decision-making may be more valuable when deciding on appropriate goal weight reduction.

Association Between Nonsurgical Weight Loss From Body Mass Index >40 to Body Mass Index <40 and Complications and Readmissions Following Total Hip Arthroplasty

BACKGROUND

Elevated body mass index (BMI) is a risk factor for adverse outcomes following total hip arthroplasty (THA). It is unknown if preoperative weight loss to a BMI <40 kg/m² is associated with reduced risk of adverse outcomes.

METHODS

We retrospectively reviewed elective, primary THA performed at an academic center from 2015 to 2019. Patients were split into groups based on their BMI trajectory prior to THA: BMI consistently <40 ("BMI <40"); BMI >40 at the time of surgery ("BMI >40"); and BMI >40 within 2 years preoperatively, but <40 at the time of surgery ("Weight Loss"). Length of stay (LOS), 30-day readmissions, and complications as defined by Centers for Medicare and Medicaid Services were compared between groups using parsimonious regression models and Fisher's exact testing. Adjusted analyses controlled for sex, age, and American Society of Anesthesiologists class.

RESULTS

In total, 1589 patients were included (BMI <40: 1387, BMI >40: 96, Weight Loss: 106). The rate of complications in each group was 3.5%, 6.3%, and 8.5% and the rate of 30-day readmissions was 3.0%, 4.2%, and 7.5%, respectively. Compared to the BMI <40 group, the weight loss group had a significantly higher risk of 30-day readmission (odds ratio [OR] 2.70, 95% confidence interval [CI] 1.19-6.17, P = .02), higher risk of any complication (OR 2.47, 95% CI 1.09-5.59, P = .03), higher risk of mechanical complications (OR 3.07, 95% CI 1.14-8.25, P = .03), and longer median LOS (16% increase, P = .002). The BMI >40 group had increased median LOS (10% increase, P = .03), but no difference in readmission or complications (P > .05) compared to BMI <40.

CONCLUSION

Weight loss from BMI >40 to BMI <40 prior to THA was associated with increased risk of readmission and complications compared to BMI <40, whereas BMI >40 was not.

LEVEL OF EVIDENCE

Level III - Retrospective Cohort Study.

Does Surgical Approach for Total Hip Arthroplasty Impact Infection Risk in the Obese Patient? A Systematic Review

This systematic review evaluated the combined effects of obesity and surgical approach on periprosthetic joint infection (PJI) rates after total hip arthroplasty (THA). Wound complication and PJI rates were elevated among patients with body mass index (BMI) of 30 kg/m2 or greater and 35 kg/m2 or greater, respectively, with the direct anterior approach (DAA). A BMI of 30 kg/m2 or greater also increased the risk of PJI with the posterior approach. Patients with BMI of 30 kg/m2 or greater undergoing anterolateral approach THA did not have increased risk of PJI. Patients with elevated BMI (≥30 kg/m2) are at risk for PJI, regardless of approach. Patients undergoing DAA THA who have BMI of 35 kg/m2 or greater may have an increased risk of PJI compared with those undergoing THA with other approaches. [Orthopedics. 2022;45(2):e67-e72.].

[Risk management in orthopedic surgery : Stratification and adjustment of patient-individual risk factors]

Preoperative identification of patients at risk of postoperative complications enables better patient education and surgical planning for the orthopedic surgeon. In addition to demographic and intervention-specific factors, a variety of instruments are available for individual risk assessment. The concept of frailty seems to be promising to identify patients at risk. Modifiable risk factors such as malnutrition, anemia, obesity, smoking, and insufficiently controlled diabetes mellitus are common in elective orthopedic patients. With the use of screening protocols, modifiable risk factors can be identified and optimized preoperatively in order to reduce the individual risk of complications. Recommendations regarding preoperative risk stratification and modification prior to elective hip replacement have meanwhile been incorporated in national guidelines.

Elective Surgery in Adult Patients with Excess Weight: Can Preoperative Dietary Interventions Improve Surgical Outcomes? A Systematic Review

This systematic review summarises the literature regarding the impact of preoperative dietary interventions on non-bariatric surgery outcomes for patients with excess weight/obesity, a known risk factor for poor surgical outcomes. Four electronic databases were searched for non-bariatric surgery studies that evaluated the surgical outcomes of a preoperative diet that focused on weight/fat loss or improvement of liver steatosis. Meta-analysis was unfeasible due to the extreme heterogeneity of variables. Fourteen studies, including five randomised controlled trials, were selected. Laparoscopic cholecystectomy, hernia repair, and liver resection were most studied. Diet-induced weight loss ranged from 1.4 kg to 25 kg. Preoperative very low calorie diet (≤800 kcal) or low calorie diet (≤900 kcal) for one to three weeks resulted in: reduction in blood loss for two liver resection and one gastrectomy study (-27 to -411 mL, p < 0.05), and for laparoscopic cholecystectomy, reduction of six minutes in operating time (p < 0.05) and reduced difficulty of aspects of procedure (p < 0.05). There was no difference in length of stay (n = 7 studies). Preoperative ≤ 900 kcal diets for one to three weeks could improve surgical outcomes for laparoscopic cholecystectomy, liver resection, and gastrectomy. Multiple randomised controlled trials with common surgical outcomes are required to establish impact on other surgeries.

Surgeon Decision-Making for Individuals With Obesity When Indicating Total Joint Arthroplasty

BACKGROUND

Obesity is a risk factor for complications after total joint arthroplasty (TJA). This study analyzed the impact of individual surgeon demographics, financial concerns, and other factors in determining patient candidacy for TJA based on body mass index (BMI).

METHODS

A 21-question survey was approved by the American Association of Hip and Knee Surgeons Research Committee for distribution to its membership. Objective questions asked about surgeon or hospital BMI thresholds for offering TJA. Subjective questions asked about physician comfort discussing topics including obesity, bariatric surgery, and weight loss before TJA, as well as insurance and age considerations.

RESULTS

For TJA procedures, 49.9% of surgeons had a BMI cutoff at 40, 24.5% at 45, and 8.3% at 50. At a BMI cutoff of 40, 23.8% of surgeons felt their patient volume would be adversely affected, whereas at a BMI cutoff of 35, 50% of surgeons felt their patient volume would be adversely affected. Surgeons were more likely to not perform total hip arthroplasty on patients with morbid obesity than total knee arthroplasty (P = .037). Significantly more academic surgeons did not have cutoffs for total hip arthroplasty (P = .003) or total knee arthroplasty (P < .001) compared with all other practice settings.

CONCLUSION

There are myriad factors that affect surgeon BMI thresholds for offering elective TJA including poor outcomes, hospital thresholds, financial considerations, and the well being of the patient. Further work should be performed to minimize the risks associated with TJA while providing the best possible care to patients with morbid obesity.

Lower Extremity Girth Does Not Predict Complications in TKA

BACKGROUND

Obese patients have increased complications after total knee arthroplasty (TKA). A body mass index (BMI) cutoff of 40 is frequently used to determine eligibility for TKA. Patients with a BMI <40 and extremely large legs which may predispose them to complications are approved for surgery because they fall below this cutoff. Alternatively, patients with truncal obesity and a BMI >40 are accepted because they have thin legs. We sought to determine whether BMI or girth should be used to determine eligibility.

METHODS

453 patients who underwent TKA were included. A lower extremity girth (LEG) ratio was calculated dividing the width of the soft tissue envelope by bone width on lateral radiographs. Receiver operator curves were generated to predict 90-day complications.

RESULTS

There was no difference in median LEG ratio between patients with or without a complication (P = .08). Receiver operator curves indicated that size of the soft tissue envelope had no utility in predicting complications. There was no correlation between LEG ratio and specific complications such as infection, malalignment, or wound complications. Using a LEG ratio threshold of 4.834, the sensitivity and specificity for predicting complications were 48% and 64%, respectively. The median BMI for patients with no complication was 32.3 and 35 for patients with a complication (P = .07).

CONCLUSION

Complications are not necessarily associated with size of the soft tissue envelope in TKA.Decisions concerning TKA should not be made solely on the size of a patient's leg.

LEVEL OF EVIDENCE

Level III (retrospective comparative study).

Increasing Reoperations and Failures With Increasing BMI in Patients Undergoing 2-Stage Exchange for Infected Total Hip Arthroplasty

BACKGROUND

While morbid obesity is associated with increased infection after total hip arthroplasty, little is known on the outcomes after 2-stage reimplantation for prosthetic joint infection (PJI) in this population. The purpose of this study is to evaluate the impact of morbid obesity (body mass index>40 kg/m2) on reinfection, postoperative complications, readmissions, and reoperations.

METHODS

We conducted a retrospective review of 107 patients undergoing first time 2-stage reimplantation for PJI from 2013 to 2019. 18 patients (50% women) with body mass index>40 kg/m2 were identified. To minimize confounders, three propensity score matched cohorts were created, yielding 16 nonobese (<30 kg/m2), 16 obese (30-39.9 kg/m2), and 18 morbidly obese (>40 kg/m2) patients. Outcomes were compared using chi-square or Fisher's exact tests. All patients had minimum 12-month follow-up, with mean follow-up of 36.3, 30.1, and 40.0 months in the nonobese, obese, and morbidly obese cohorts, respectively.

RESULTS

Compared with nonobese patients, morbidly obese patients had a higher rate of reinfection (0% vs 33%, P = .020 and higher likelihood of length of stay>4 days (19% vs 61%, P = .012). In addition, compared with nonobese and obese patients, morbidly obese patients had higher rate of return to the operating room for any reason (13% vs 19% vs 50%, respectively, P = .020). No differences between cohorts were found regarding complications, death, or revision surgery.

CONCLUSION

Morbidly obese patients have significantly increased risk of reinfection and reoperation after 2-stage reimplantation for PJI when compared with obese and nonobese patients. These data can be used to counsel morbidly obese patients contemplating total hip arthroplasty and supports the notion of deferring arthroplasty in this population pending optimization.

Failure to Medically Optimize Before Total Hip Arthroplasty: Which Modifiable Risk Factor Is the Most Dangerous?

Background

There is mounting evidence that smoking, abnormal body mass index (BMI), uncontrolled diabetes, and poor nutritional status are associated with complications after total hip arthroplasty (THA). The goal of the present study was to evaluate the consequences of failure to medically optimize Medicare-eligible patients with respect to these key modifiable health targets by assessing complications in the early postoperative period after THA.

Methods

The National Surgical Quality Improvement Program database was queried for all primary THAs performed in 2018. Data were collected on preoperative serum albumin, BMI, diabetes, and tobacco use as well as postoperative infections, readmissions, complications, and mortality. We identified 47,924 THA patients with a median BMI of 29 kg/m² and age of 72 years, and 60% of whom were female.

Results

We found that preoperative albumin <3.5 g/dL, BMI ≥40 kg/m², tobacco use, and diabetes were all individually associated with increased risk of postoperative complications. Serum albumin <3.5 g/dL was the greatest overall risk factor for infection (odds ratio [OR]: 3.1, 95% confidence interval [CI]: 2.3-4.4, P < .0001), readmission (OR: 2.2, 95% CI: 1.9-2.5, P < .0001), any complication (OR: 4.2, 95% CI: 3.8-4.6, P < .0001), and mortality (OR: 7.5, 95% CI: 5.3-10.6, P < .0001).

Conclusions

Low albumin, elevated BMI, tobacco use, and diabetes are associated with increased risk of postoperative infection, readmission, any complication, and mortality after primary THA. Low albumin poses the greatest risk of these. Preoperative optimization should be obtained in all patients before elective surgery, and the final decision for surgery should be individually made between a surgeon and patient.

Level of Evidence

IV.

Preoperative risk stratification minimizes 90-day complications in morbidly obese patients undergoing primary total knee arthroplasty

AIMS

It has been shown that the preoperative modification of risk factors associated with obesity may reduce complications after total knee arthroplasty (TKA). However, the optimal method of doing so remains unclear. The aim of this study was to investigate whether a preoperative Risk Stratification Tool (RST) devised in our institution could reduce unexpected intensive care unit (ICU) transfers and 90-day emergency department (ED) visits, readmissions, and reoperations after TKA in obese patients.

METHODS

We retrospectively reviewed 1,614 consecutive patients undergoing primary unilateral TKA. Their mean age was 65.1 years (17.9 to 87.7) and the mean BMI was 34.2 kg/m² (SD 7.7). All patients underwent perioperative optimization and monitoring using the RST, which is a validated calculation tool that provides a recommendation for postoperative ICU care or increased nursing support. Patients were divided into three groups: non-obese (BMI < 30 kg/m², n = 512); obese (BMI 30 kg/m² to 39.9 kg/m², n = 748); and morbidly obese (BMI > 40 kg/m², n = 354). Logistic regression analysis was used to evaluate the outcomes among the groups adjusted for age, sex, smoking, and diabetes.

RESULTS

Obese patients had a significantly increased rate of discharge to a rehabilitation facility compared with non-obese patients (38.7% (426/1,102) vs 26.0% (133/512), respectively; p < 0.001). When stratified by BMI, discharge to a rehabilitation facility remained significantly higher compared with non-obese (26.0% (133)) in both obese (34.2% (256), odds ratio (OR) 1.6) and morbidly obese (48.0% (170), OR 3.1) patients (p < 0.001). However, there was no significant difference in unexpected ICU transfer (0.4% (two) non-obese vs 0.9% (seven) obese (OR 2.5) vs 1.7% (six) morbidly obese (OR 5.4); p = 0.054), visits to the ED (8.6% (44) vs 10.3% (77) (OR 1.3) vs 10.5% (37) (OR 1.2); p = 0.379), readmissions (4.5% (23) vs 4.0% (30) (OR 1.0) vs 5.1% (18) (OR 1.4); p = 0.322), or reoperations (2.5% (13) vs 3.3% (25) (OR 1.2) vs 3.1% (11) (OR 0.9); p = 0.939).

CONCLUSION

With the use of a preoperative RST, morbidly obese patients had similar rates of short-term postoperative adverse outcomes after primary TKA as non-obese patients. This supports the assertion that morbidly obese patients can safely undergo TKA with appropriate perioperative optimization and monitoring. Cite this article: Bone Joint J 2021;103-B(6 Supple A):45-50.

Case Report: Off Label Utilization of Topiramate and Metformin in Patients With BMI ≥50 kg/m2 Prior to Bariatric Surgery

FDA approved anti-obesity medications may not be cost effective for patients struggling with pre-operative weight loss prior to bariatric surgery. Metformin, a biguanide, and Topiramate, a carbonic anhydrase inhibitor, both cost effective medications, have demonstrated weight loss when used for the treatment of type 2 diabetes or seizures, respectively. The aim of the three cases is to demonstrate the clinical utility of topiramate and metformin for preoperative weight loss in patients with a body mass index (BMI) ≥ 50 kg/m² prior to bariatric surgery who are unable to follow the bariatric nutritional prescription due to a dysregulated appetite system Each patient was prescribed metformin and/or topiramate in an off-label manner in conjunction with lifestyle modifications and achieved >8% total body weight loss during the preoperative period.

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

BACKGROUND

Although morbid obesity is an established risk factor for periprosthetic joint infection following total hip arthroplasty and total knee arthroplasty, little is known regarding the infection control rate of this cohort following debridement, antibiotics, and implant retention (DAIR). The purpose of this study is to investigate the infection control rate following DAIR in a morbidly obese patient cohort compared to a nonobese patient cohort and discern the relationship between time from diagnosis to treatment and risk of DAIR failure.

METHODS

Results of all DAIR procedures were retrospectively reviewed across 4 institutions. Those with a body mass index of at least 40 kg/m² were matched 2:1 on the basis of patient age, sex, date of surgery, and presence of staphylococcal species in culture to a cohort of patients with body mass index of <30 kg/m². Demographic variables were collected for each patient. Kaplan-Meier survivorship curves were constructed and multivariable Cox regression was performed for analysis.

RESULTS

The morbidly obese group experienced a higher treatment failure rate (57.9%) compared to the nonobese group (36.8%; P = .035). Morbid obesity and major depressive disorder/generalized anxiety disorder diagnosis significantly increased the risk of failure, with hazard ratios of 1.82 and 2.09, respectively. Morbidly obese patients who received DAIR within 48 hours of symptom presentation did not face an increased risk of reinfection compared to nonobese patients.

CONCLUSION

Our findings suggest morbidly obese patients face an increased risk of DAIR failure; however, this risk can be mitigated if DAIR is received within 48 hours of symptom onset.

Impact of Morbid Obesity on Overnight Stay and Early Complications With Outpatient Arthroplasty

BACKGROUND

The shift toward outpatient joint arthroplasty is rapidly growing, but concerns still remain on whether certain patients should be excluded from same-day discharge arthroplasty. The purpose of this study is to evaluate whether morbid obesity is a risk factor for perioperative complications after outpatient joint arthroplasty.

METHODS

A retrospective review was performed from 2013 to 2017 of all outpatient primary total hip, total knee, partial knee, and revision hip and knee arthroplasties, yielding a cohort of 4863 patients (5988 arthroplasty procedures). Patients were separated and analyzed based on 2 groups: nonmorbidly obese (NMO) (BMI < 40 kg/m²) and morbidly obese (MO) (BMI ≥ 40 kg/m²). The NMO group consisted of 4870 arthroplasties and the MO group consisted of 1118 arthroplasties. Overnight stays, medical complications, and early perioperative complications were assessed between groups.

RESULTS

Overnight stays occurred in 5.4% of NMO patients and 9.1% of MO patients (P < .001), with medical reasons for the overnight stay occurring in 3.2% of NMO and 6.4% of MO patients (P < .001). Respiratory/sleep apnea was the leading medical reason leading to overnight stay occurring in 4% of MO patients and 0.8% of NMO patients (P < .001). There was no significant difference between groups in direct facility transfers, emergency room visits/admissions, or medical complications within 90 days. Wound revisions, nonrevision surgery, or revisions within 90 days were significant between groups.

CONCLUSION

MO patients did not have an increased risk of 90-day medical complications, readmission, or revisions after outpatient arthroplasty. However, MO patients did have a significantly higher incidence of overnight stay.

Perioperative Complications Stratified by Body Mass Index for the Direct Anterior Approach to Total Hip Arthroplasty

BACKGROUND

Previous studies have addressed the increased risk of perioperative complications in the obese and morbidly obese populations undergoing total hip arthroplasty. Over the last 15 years, the direct anterior approach has increased in popularity. The purpose of this study is to compare the 90-day perioperative complication rate of total hip arthroplasty performed through the direct anterior approach stratified by body mass index (BMI).

METHODS

Perioperative complications both intraoperative and up to 90 days postoperative were identified in a case series of 1808 primary total hip arthroplasties performed through a direct anterior approach. The patients were stratified according to BMI. Demographics of age, side, sex, and American Society of Anesthesiologists score were recorded. Medical and surgical complications including National Surgical Quality Improvement Program complications, length of stay, reoperation rate, readmission rate, and length of operation were recorded. Bivariate analysis and analysis of variance were performed.

RESULTS

Morbidly obese patients (BMI > 40) demonstrated increased American Society of Anesthesiologists scores, increased surgical times with statistically significant increase in number of patients with surgical complications, National Surgical Quality Improvement Program complications, deep infection, and wound breakdown. Grading the severity of complications also demonstrated the morbidly obese had a higher risk of experiencing more severe complications. Underweight patients (BMI < 18.5) demonstrated a statistically significant readmission rate.

CONCLUSION

In stratifying patients undergoing the direct anterior approach for total hip arthroplasty by BMI, a greater rate of surgical complications both in number and in severity occurs with the morbidly obese undergoing total hip arthroplasty through a direct anterior approach.

The Association between High Body Mass Index and Early Clinical Outcomes in Patients with Proximal Femur Fractures

BACKGROUND

Fractures of the proximal femur constitute daily work in orthopedic trauma surgery. With the continuous increase of obesity in the general population, surgeons face several known technical challenges. The aim of this study was to investigate the association of high body mass index (BMI) in patients with proximal femur fractures with intra- and postoperative adverse events, as well as with functional outcomes after successful surgery.

METHODS

In this retrospective, single-center cohort study, 950 patients who sustained a fracture of the proximal femur (femoral neck fracture or trochanteric fracture) and underwent surgical treatment at our level I trauma center between 2003 and 2015 were included. Patient-specific data were obtained in regard to demographics, comorbidities, and fracture morphology. In-hospital postoperative complications (i.e., need for revision surgery, wound site infection, pneumonia, urinary tract infection, necessary transfusion, and deep-vein thrombosis) were analyzed, along with the length of hospitalization and overall mortality rate. Functional outcome was assessed using the Barthel index and the patient's ability to walk on crutches. Mortality rate and need for revision surgery were assessed over a two-year time period. Any adverse event was correlated to one of the four WHO's BMI groups.

RESULTS

The cohort included 80 (8.4%) underweight patients, 570 (60.0%) normal weight patients, 241 (25.4%) overweight patients, and 59 (6.2%) obese patients. We found more femoral neck fractures (506, or 53%) than trochanteric fractures (444, or 47%). In bivariate analysis, no significant difference was found in regard to overall mortality or postoperative complications. Hospitalization time (LOS) differed between the underweight (12.3 ± 4.8 days), normal (13.6 ± 7.8 days), overweight (14.2 ± 11.7 days), and obese patients (16.0 ± 9.7 days) (p = 0.040). Operation time increased stepwise with increasing BMI: underweight = 85.3 ± 42.9 min; normal weight = 90.2 ± 38.2 min; overweight = 99.9 ± 39.9 min; obese = 117.2 ± 61.5 min (p < 0.001). No significant difference was found by analyzing functional outcomes. However, patients with intermediate BMI levels (18.5-30 kg/m2) tended to achieve the best results, as represented by a higher Barthel index score and the patient's ability to walk on crutches.

CONCLUSION

Increased BMI in patients with proximal femur fractures is associated with both longer operation time and length of hospitalization (LOS). Postoperative mobilization and functional outcomes appear to follow a reversed J-curve distribution (with overweight patients showing the best functional results), whereas both obese and underweight patients have associated poorer function.

Bariatric Surgery Prior to Total Hip Arthroplasty Is Cost-Effective in Morbidly Obese Patients

BACKGROUND

The cost-effectiveness of bariatric surgery to achieve weight loss prior to total hip arthroplasty (THA), and decrease the complications and costs associated with THA in the morbidly obese, is unknown. This study evaluated the cost-effectiveness of bariatric surgery prior to THA for morbidly obese patients with end-stage hip osteoarthritis (OA).

METHODS

A state-transition Markov model was constructed to compare the cost-utility of 2 treatment protocols for patients with morbid obesity and end-stage hip OA: (1) immediate THA and (2) bariatric surgery 2 years prior to THA (combined protocol). The analysis was performed from both a payer and a societal perspective using direct and indirect costs over a 40-year time horizon. Utilities, associated costs, and probabilities for health state transitions were derived from the literature. One-way, 2-way and probabilistic sensitivity analyses were performed to validate the robustness of the base case results, using the standard willingness-to-pay threshold of $100,000/quality-adjusted life years.

RESULTS

From the societal perspective, the combined protocol was more effective (13.16 vs 12.26) with less cost ($91,717 vs $92,684) and thus was the dominant strategy over immediate THA. These results were stable across broad ranges for independent model variables. Monte Carlo simulation with 100,000 samples demonstrated that bariatric surgery prior to THA was the preferred cost-effective strategy over 95% of the time from both a societal and payer perspective.

CONCLUSION

In the morbidly obese patient with end-stage hip OA, bariatric surgery prior to THA is a cost-effective strategy for improving quality of life and decreasing societal and payer costs.

LEVEL OF EVIDENCE

II.

Evaluating the effects of a total joint education class on patient outcomes

As the population ages and as people live longer, there is a growing demand for total hip and total knee procedures. Possible outcomes for these procedures is a postoperative joint infection (PJI) that can cause long postoperative lengths of stay (LOS) in the hospital. The PJIs can also negatively impact the quality of life for the patient. Using the roadmap of the continuous quality improvement theory, the purpose of this quantitative study was to examine the relationship between the independent variables (joint education class participation, body mass index [BMI], A1c, and smoking) and dependent variables (PJI and LOS). To evaluate the relationship with PJI, a logistical regression analyzed the sample population of 1216 patients and indicated a relationship between joint education class attendance and PJI among total hip patients, but not total knee patients when controlling for the other variables. The regression also indicated a significant relationship between BMI and smoking and PJIs, but it did not show a relationship between A1c/diabetes and PJI. To evaluate the relationship between joint class education and LOS a Poisson regression indicated that those who did not attended the joint education class, whether they had total hips or total knees, had a longer postoperative LOS. The implications for positive social change involve providing information to physicians and administrators regarding the effectiveness of the total joint education class in improving outcomes. This information could be used to justify the need for patient compliance with the class and/or the possible need for additional resources to support the total joint education program.

Underweight patients are at just as much risk as super morbidly obese patients when undergoing anterior cervical spine surgery

BACKGROUND CONTEXT

Past studies have focused on the association of high body mass index (BMI) on spine surgery outcomes. These investigations have reported mixed conclusions, possible due to insufficient power, poor controlling of confounding variables, and inconsistent definitions of BMI categories (e.g. underweight, overweight, and obese). Few studies have considered outcomes of patients with low BMI.

PURPOSE

To analyze how anterior cervical spine surgery outcomes track with World Health Organization categories of BMI to better assess where along the BMI spectrum patients are at risk for adverse perioperative outcomes.

DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

Patients undergoing elective anterior cervical spine surgery were abstracted from the 2005 to 2016 American College of Surgeons National Surgical Quality Improvement Program database.

OUTCOME MEASURES

Thirty-day adverse events, hospital readmissions, postoperative infections, and mortality.

METHODS

Patients undergoing anterior cervical spine procedures (anterior cervical discectomy and fusion, anterior cervical corpectomy, cervical arthroplasty) were identified in the 2005 to 2016 National Surgical Quality Improvement Program database. Patients were then aggregated into modified World Health Organization categories of BMI. Odds ratios of adverse outcomes, normalized to average risk of normal weight subjects (BMI 18.5-24.9 kg/m²), were calculated. Multivariate analyses were then performed on aggregated adverse outcome categories controlling for demographics (age, sex, functional status) and overall health as measured by the American Society of Anesthesiologists classification.

RESULTS

In total, 51,149 anterior cervical surgery patients met inclusion criteria. Multivariate analyses revealed the odds of any adverse event to be significantly elevated for underweight and super morbidly obese patients (Odds Ratios [OR] of 1.62 and 1.55, respectively). Additionally, underweight patients had elevated odds of serious adverse events (OR=1.74) and postoperative infections (OR=1.75) and super morbidly obese patients had elevated odds of minor adverse events (OR=1.72). Relative to normal BMI patients, there was no significant elevation for any adverse outcomes for any of the other overweight/obese categories, in fact some had reduced odds of various adverse outcomes.

CONCLUSIONS

Underweight and super morbidly obese patients have the greatest odds of adverse outcomes after anterior cervical spine surgery. The current study identifies underweight patients as an at-risk population that has previously not received significant focus. Physicians and healthcare systems should give additional consideration to this population, as they often already do for those at the other end of the BMI spectrum.

The Phenomenon of "Obesity Paradox" in Neck of Femur Fractures

Objective

To determine the association of body mass index (BMI) with 30 days and 1-year mortality outcomes of orthopedic elderly patients after hip fracture surgery.

Methods

This is prospective study conducted at Department of Orthopaedics, at a tertiary care public sector hospital in Karachi between Jan-2016 to Jan-2018. In this short follow-up study, we included the data of 490 patients, who were operated for neck of femur fractures in a public sector tertiary care hospital between Jan-2016 to Jan-2018. Patients were divided into different categories on the basis of BMI; BMI <20 Kg.m^-2 underweight, 20-24.99 Kg.m^-2 normal weight, BMI 25-29.99 Kg.m^-2 overweight, ≥30 obese. Mortality at 30 days and 1-year mortality were primary study end-points.

Results

Rate of re-admission within 30 days, major adverse cardiovascular events (MACE) within 30 days and 30 days mortality was high in underweight and lowest in obese patients. Thirty-day mortality rate was 2.7% in underweight, 1.3% in normal weight, 0.64% in over-weight and 0.0% in obese patients but this was not significant statistically (p-value 0.29). One-year mortality rate was significantly high in under-weight patients, 34.2%, 25.9% in normal weight, 21.4% in overweight and only 14.5% in obese patients (p-value 0.009). Age ≥ 65 years (odds ratio 0.40 (0.26-0.63), and ASA III-IV (odds ratio; 0.27 (0.16-0.45) are also significant risk factors of 1-year mortality.

Conclusion

BMI classification can serve as an important indicator of adverse early outcomes after hip fracture surgery. Over-weight and obese patients have better survival outcomes and have lower 1-year mortality rate.

Correlation between Body Mass Index and Periprosthetic Joint Infection following Total Joint Arthroplasty: A protocol for systematic review and meta analysis

BACKGROUND

Despite rapid reports on the correlation between body mass index (BMI) and periprosthetic joint infection (PJI) after total joint arthroplasty, some have conducted regression tests or meta-analyses with controversial results. In this study, we systematically meta-analyzed relevant trials and carefully evaluated the correlation for verification.

METHODS

Literature on the correlation between BMI and PJI following total joint arthroplasty was retrieved in PubMed, Embase and Cochrane Library due September 2019. Stata 13.0 software was adopted for data synthesis and analyses of publication bias and sensitivity. Random-effect models were used to summary the overall estimate of the multivariate adjusted odds ratio (OR)/hazard ratio/rate ratio with 95% confidence intervals (CIs).

RESULTS

A total of 29 observational studies representing 3,204,887 patients were included. The meta-analysis revealed that the risk of postoperative PJI significantly increased by 1.51 times in the obese group (OR = 1.51; 95% CI = 1.30-1.74 for the obese group vs. the non-obese group), and by 3.27 times in the morbid obese group (OR = 3.27; 95% CI = 2.46-4.34 for the morbid obese group vs the non-morbid obese group). A significant association remained consistent, as indicated by subgroup analyses and sensitivity analyses.

CONCLUSION

Our findings demonstrate that postoperative PJI is positively correlated with BMI, with obese patients showing a greater risk of developing PJI than non-obese patients. Similarly, morbid obese patients present a higher risk of PJI than non-morbid obese patients. However, this conclusion needs to be corroborated by more prospective studies.

Total Hip Arthroplasty in the Obese Patient: Tips and Tricks and Review of the Literature

AIM

There is a lack of consensus on the optimal method of performing primary hip arthroplasty in obese patients and limited evidence. This article presents a series of considerations based on the authors' experiences as well as a review of the literature.

PREOPERATIVE CARE

In the preoperative phase, an informed consent process is recommended. Weight loss is recommended according to NHS England guidelines, and body habitus should be taken into account. When templating, steps are taken to avoid overestimating the implant size.

SURGICAL PROCEDURE

During the surgical procedure, specialist bariatric equipment is utilised: bariatric beds, extra supports, hover mattresses, longer scalpels, diathermy, cell saver and minimally invasive surgery equipment. Communication with the anaesthetist and surgical team to anticipate is vital. Intraoperative sizing and imaging, if required, should be considered. Pneumatic foot pumps are preferable for VTE prophylaxis. Regional anaesthesia is preferred due to technical difficulty. IV antibiotics and tranexamic acid are recommended. The anterior and posterior surgical approaches are most frequently used; we advocate posterior. Incisions are extensile and a higher offset is considered intraoperatively, as well as dual mobility and constrained liners to reduce dislocation risk. When closing the wound, Charnely button and sponge should be considered as well as negative pressure wound dressings (iNPWTd) and drains.

POST-OPERATIVE CONSIDERATIONS

Postoperatively, difficult extubation should be anticipated with ITU/HDU beds available. Epidural anaesthetics for postoperative pain management require higher nursing vigilance. Chemical prophylaxis is recommended.

CONCLUSION

Despite being technically more difficult with higher risks, functional outcomes are comparable with patients with a normal BMI.

Utilization of Resources by Patients Who Are Morbid and Super Obese Admitted to a Tertiary Care Center

OBJECTIVES

Data regarding the characteristics of patients who are morbidly and super obese, and the resources they use in nonbariatric hospital settings are limited. The aims of our study were to explore the frequency of inpatient admissions of patients who are morbid (body mass index [BMI] ≥ 40 kg/m) and super obese (BMI ≥ 50 kg/m), their specific characteristics, and to identify their utilization of hospital services and resources, 30-day readmission rates, safe patient handling equipment, and patient clinical outcomes.

METHODS

We conducted a retrospective chart review of adult patients hospitalized at our institution (n = 1670) who are morbidly obese or super obese. We collected and compared data regarding the characteristics of patients, the services and resources used, the use of any special handling equipment, and patient clinical outcomes.

RESULTS

After accounting for confounding variables, wound care and occupational therapy services were more likely to be required for the patients who are super obese (odds ratio [OR] = 1.49, P = 0.04) than for those who are morbidly obese (odds ratio [OR] = 1.36, P = 0.02). Use of safe patient handling devices was twice as likely for the super obese group (OR = 2.09, P < 0.01). There was no difference in mortality rates between the two patient groups (P = 0.81); patients who are super obese had higher odds of prolonged hospital stay by 32% (P = 0.009).

CONCLUSIONS

This study provides an understanding of the characteristics of patients with BMI of 40 kg/m or greater who are admitted to the hospital, the resources and services use, and their clinical outcomes. There is also a need to develop an organizational protocol to ensure safe handling using the right devices and activation of appropriate consult services.

Greater risks of complications, infections, and revisions in the obese versus non-obese total hip arthroplasty population of 2,190,824 patients: a meta-analysis and systematic review

BACKGROUND

Obesity is an epidemic, especially in developed countries. This affects the general health of these patients, especially when they are having a major surgical procedure such as total hip arthroplasty (THA). Several articles have described the effects of obesity on THA with varying conclusions. This meta-analysis aims to compare the outcomes, complications, and peri-operative parameters of THA in the obese (BMI≥30 kg/m²) vs non-obese (BMI<30 kg/m²) population as well as a subgroup analysis of morbidly obese (BMI≥40 kg/m²) vs non-obese population.

METHODS

A multi-database search was performed according to PRISMA guidelines. Data from studies assessing the outcomes and complications of THA in the obese and non-obese population were extracted and analyzed.

RESULTS

Sixty-seven studies were included in this meta-analysis, consisting of 581,012 obese and 1,609,812 non-obese patients. Meta-analysis could not be performed on patient reported outcome measures due to heterogeneous reporting methods. Obese patients had a higher risk of all complications (OR = 1.53, 95%CI: 1.30-1.80, P < 0.001), deep infections (OR = 2.71, 95%CI: 2.08-3.53, P < 0.001), superficial infections (OR = 1.99, 95%CI: 1.55-2.55, P < 0.001), dislocations (OR = 1.72, 95%CI: 1.66-1.79, P < 0.001), reoperations (OR = 1.61, 95%CI: 1.40-1.85, P < 0.001), revisions (OR = 1.44, 95%CI: 1.32-1.57, P < 0.001), and readmissions (OR = 1.37, 95%CI: 1.15-1.63, P < 0.001). When sub-group analysis of morbidly obese (BMI≥40 kg/m²) patients was performed, the risks of all these parameters were even greater.

CONCLUSION

Obese and morbidly obese patients are at higher risks of complications post THA than non-obese patients. Surgeons should be aware of these risks in order to counsel patients and adopt prophylactic strategies to reduce these risks where applicable.

Total hip arthroplasty in obesity: separating 'fat' from fiction

Obesity is a modern-day epidemic with increasing prevalence that is directly impacting the global burden of primary total hip arthroplasty. The risk of requiring total hip arthroplasty for osteoarthritis increases incrementally with increasing obesity class. Surgical intervention in obese patients presents a set of unique challenges that should be recognized by the treating medical team. Although predominantly satisfactory outcomes have been reported, perioperative anaesthetic and surgical concerns require thorough patient assessment. There is an increased potential risk of thrombogenic and septic complications, but the body mass index cutoff level beyond which total hip arthroplasty should not be offered in the obese patient remains controversial. Preoperative medical optimization of the patient and appropriate intraoperative interventions are essential to mitigate the risk of complications.

2018 International Consensus Meeting on Musculoskeletal Infection: Research Priorities from the General Assembly Questions

Musculoskeletal infections (MSKI) remain the bane of orthopedic surgery, and result in grievous illness and inordinate costs that threaten healthcare systems. As prevention, diagnosis, and treatment has remained largely unchanged over the last 50 years, a 2nd International Consensus Meeting on Musculoskeletal Infection (ICM 2018, https://icmphilly.com) was completed. Questions pertaining to all areas of MSKI were extensively researched to prepare recommendations, which were discussed and voted on by the delegates using the Delphi methodology. The questions, including the General Assembly (GA) results, have been published (GA questions). However, as critical outcomes include: (i) incidence and cost data that substantiate the problems, and (ii) establishment of research priorities; an ICM 2018 research workgroup (RW) was assembled to accomplish these tasks. Here, we present the result of the RW consensus on the current and projected incidence of infection, and the costs per patient, for all orthopedic subspecialties, which range from 0.1% to 30%, and $17,000 to $150,000. The RW also identified the most important research questions. The Delphi methodology was utilized to initially derive four objective criteria to define a subset of the 164 GA questions that are high priority for future research. Thirty-eight questions (23% of all GA questions) achieved the requisite > 70% agreement vote, and are highlighted in this Consensus article within six thematic categories: acute versus chronic infection, host immunity, antibiotics, diagnosis, research caveats, and modifiable factors. Finally, the RW emphasizes that without appropriate funding to address these high priority research questions, a 3rd ICM on MSKI to address similar issues at greater cost is inevitable.