The Potential Effects of Imposing a Body Mass Index Threshold on Patient-Reported Outcomes After Total Knee Arthroplasty

Diagnosis-Specific Thresholds of the Minimal Clinically Important Difference and Patient Acceptable Symptom State for KOOS After Total Knee Arthroplasty

UPDATE

This article was updated on May 1, 2024 because of a previous error, which was discovered after the preliminary version of the article was posted online. The byline that had read "Ahmed K. Emara, MD 1 *, Ignacio Pasqualini, MD 1 *, Alison K. Klika, MS 1 , Melissa N. Orr, BS 1 , Pedro J. Rullán, MD 1 , Nicolas S. Piuzzi, MD 1 , and the Cleveland Clinic Arthroplasty Group†" now reads "Ahmed K. Emara, MD 1 *, Ignacio Pasqualini, MD 1 *, Yuxuan Jin, MS 1 , Alison K. Klika, MS 1 , Melissa N. Orr, BS 1 , Pedro J. Rullán, MD 1 , Nicolas S. Piuzzi, MD 1 , and the Cleveland Clinic Arthroplasty Group†".

BACKGROUND

Literature-reported minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) thresholds for patient-reported outcome measures demonstrate marked variability. The purpose of this study was to determine the minimal detectable change (MDC), MCID, and PASS thresholds for the Knee injury and Osteoarthritis Outcome Score (KOOS) Pain subdomain, Physical Function Short Form (PS), and Joint Replacement (JR) among patients with osteoarthritis (OA) who underwent primary total knee arthroplasty (TKA).

METHODS

A prospective cohort of 6,778 patients who underwent primary TKA was analyzed. Overall, 1-year follow-up was completed by 5,316 patients for the KOOS Pain, 5,018 patients for the KOOS PS, and 4,033 patients for the KOOS JR. A total of 5,186 patients had an OA diagnosis; this group had an average age of 67.0 years and was 59.9% female and 80.4% White. Diagnosis-specific MDCs and MCIDs were estimated with use of a distribution-based approach. PASS values were estimated with use of an anchor-based approach, which corresponded to a response to a satisfaction question at 1 year postoperatively.

RESULTS

The MCID thresholds for the OA group were 7.9 for the KOOS Pain, 8.0 for the KOOS PS, and 6.7 for the KOOS JR. A high percentage of patients achieved the MCID threshold for each outcome measure (KOOS Pain, 95%; KOOS PS, 88%; and KOOS JR, 94%). The MDC 80% to 95% confidence intervals ranged from 9.1 to 14.0 for the KOOS Pain, 9.2 to 14.1 for the KOOS PS, and 7.7 to 11.8 for the KOOS JR. The PASS thresholds for the OA group were 77.7 for the KOOS Pain (achieved by 73% of patients), 70.3 for the KOOS PS (achieved by 68% of patients), and 70.7 for the KOOS JR (achieved by 70% of patients).

CONCLUSIONS

The present study provided useful MCID, MDC, and PASS thresholds for the KOOS Pain, PS, and JR for patients with OA. The diagnosis-specific metrics established herein can serve as benchmarks for clinically meaningful postoperative improvement. Future research and quality assessments should utilize these OA-specific thresholds when evaluating outcomes following TKA. Doing so will enable more accurate determinations of operative success and improvements in patient-centered care.

LEVEL OF EVIDENCE

Prognostic Level II . See Instructions for Authors for a complete description of levels of evidence.

Does Your Patient Need to Lose Weight? Weight Change Before and After Total Hip Arthroplasty Does Not Affect Health Care Utilization and Achievement of the Minimal Clinically Important Difference

BACKGROUND

Despite the potential negative impact of preoperative obesity on total hip arthroplasty (THA) outcomes, the association between preoperative and postoperative weight change and outcomes is much less understood. Therefore, this study aimed to determine the impact of preoperative and postoperative weight change and preoperative body mass index (BMI) on health care utilization, satisfaction, and achievement of minimal clinically important difference (MCID) for Hip Disability and Osteoarthritis Outcome Score Physical Function Short-Form (HOOS PS) and HOOS Pain.

METHODS

Patients who underwent primary elective unilateral THA between January 2016 and December 2019 were included (N = 2,868). Multivariable logistic regression assessed the association between BMI and preoperative and postoperative weight change on outcomes while controlling for demographic characteristics.

RESULTS

There was no association between preoperative weight change and prolonged length of stay (> 3 days), 90-day readmission, nonhome discharge, patient dissatisfaction at 1 year, or achievement of HOOS Pain or HOOS PS MCID. Postoperative weight loss was an independent risk factor for patient dissatisfaction at 1 year but was not associated with achievement of either HOOS Pain or HOOS PS MCID at 1-year postoperative. Preoperative obesity classes I to III were independent risk factors for nonhome discharge. Nevertheless, preoperative obesity class I and class II were associated with an increased probability of reaching HOOS Pain MCID. Preoperative BMI was not associated with an increased risk of patient dissatisfaction.

CONCLUSIONS

Preoperative weight change does not appear to influence health care utilization, satisfaction, or achievement of MCID in pain and function following THA. Postoperative weight loss may play a role as a risk factor for dissatisfaction following THA. Additionally, patients who had a higher baseline BMI may be more likely to see improvement in pain following THA. Therefore, when counseling obese patients for THA, surgeons must balance the risk of perioperative complications with the expectation of greater improvements in pain.

What Are the Diagnosis-Specific Thresholds of Minimal Clinically Important Difference and Patient Acceptable Symptom State in Hip Disability and Osteoarthritis Outcome Score After Primary Total Hip Arthroplasty?

BACKGROUND

This study aimed to determine the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) thresholds for Hip Disability and Osteoarthritis Outcome Score (HOOS) pain, physical short form (PS), and joint replacement (JR) 1 year after primary total hip arthroplasty stratified by preoperative diagnosis of osteoarthritis (OA) versus non-OA.

METHODS

A prospective institutional cohort of 5,887 patients who underwent primary total hip arthroplasty (January 2016 to December 2018) was included. There were 4,184 patients (77.0%) who completed a one-year follow-up. Demographics, comorbidities, and baseline and one-year HOOS pain, PS, and JR scores were recorded. Patients were stratified by preoperative diagnosis: OA or non-OA. Minimal detectable change (MDC) and MCIDs were estimated using a distribution-based approach. The PASS values were estimated using an anchor-based approach, which corresponded to a response to a satisfaction question at one year post surgery.

RESULTS

The MCID thresholds were slightly higher in the non-OA cohort versus OA patients. (HOOS-Pain: OA: 8.35 versus non-OA: 8.85 points; HOOS-PS: OA: 9.47 versus non-OA: 9.90 points; and HOOS-JR: OA: 7.76 versus non-OA: 8.46 points). Similarly, all MDC thresholds were consistently higher in the non-OA cohort compared to OA patients. The OA cohort exhibited similar or higher PASS thresholds compared to the non-OA cohort for HOOS-Pain (OA: ≥80.6 versus non-OA: ≥77.5 points), HOOS-PS (OA: ≥83.6 versus non-OA: ≥83.6 points), and HOOS-JR (OA: ≥76.8 versus non-OA: ≥73.5 points). A similar percentage of patients achieved MCID and PASS thresholds regardless of preoperative diagnosis.

CONCLUSIONS

While MCID and MDC thresholds for all HOOS subdomains were slightly higher among non-OA than OA patients, PASS thresholds for HOOS pain and JR were slightly higher in the OA group. The absolute magnitude of the difference in these thresholds may not be sufficient to cause major clinical differences. However, these subtle differences may have a significant impact when used as indicators of operative success in a population setting.

Despite Greater Improvement in Pain and Function Among Obese Patients Shortly After Total Knee Arthroplasty, There is No Difference in Patient-Reported Outcomes and Satisfaction Between Body Mass Index Classes at 1 Year Postoperatively

BACKGROUND

Although obesity may be associated with an increased risk of perioperative and postoperative complications after total knee arthroplasty (TKA), body mass index (BMI) cutoffs for TKA patient selection remain a controversial topic. This study aimed to investigate patient-reported outcomes, satisfaction, and pain among BMI classes at 3 months and 1 year following TKA.

METHODS

A total of 2,365 patients were categorized into Centers for Disease Control BMI classes according to preoperative values. The BMI distribution over the cohort demonstrated 7 underweight, 340 healthy weight, 731 overweight, 666 Class I, 391 Class II, and 230 Class III obesity. Preoperative and postoperative Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR), satisfaction, and pain scores were compared by BMI class by Analysis of Variance with pairwise comparisons.

RESULTS

Preoperative KOOS JR scores and satisfaction scores were both significantly greater for healthy weight patients compared to Class III patients (P < .0001). However, KOOS JR, satisfaction, and pain did not vary by BMI class postoperatively. Changes in scores from baseline suggest larger improvements with increasing BMI class, where Class III patients reported the greatest improvements in KOOS JR (23.24 ± 15.67, P < .0001) and pain scores (-3.56 ± 2.65, P < .0001) at 90 days. Significantly greater improvement with increasing BMI was also present at 1-year postoperatively for KOOS JR scores. A total of 85.8% of Class III patients reached the Minimal Clinically Important Difference for KOOS JR at 90 days compared to 76.8% of the healthy weight group (P = .03). Differences between BMI groups in the proportion reaching Minimal Clinically Important Difference at 1 year were not significant.

CONCLUSIONS

Patients of higher BMI reported greater and earlier improvements in satisfaction, knee function, and pain following TKA. Shared decision-making remains paramount to preoperative surgical evaluation. However, rationing of this surgical intervention based on BMI alone may not be warranted.

Preoperative and Postoperative Weight Change has Minimal Influence on Health Care Utilization and Patient-Reported Outcomes Following Total Knee Arthroplasty

As obesity becomes more prevalent, more patients are at risk of lower extremity osteoarthritis and subsequent total knee arthroplasty (TKA). This study aimed to test (1) the association of preoperative weight change with health care utilization and (2) the association of pre- and postoperative weight changes with failure to achieve satisfaction and minimal clinically important difference (MCID) in Knee injury and Osteoarthritis Outcome Score for pain (KOOS-Pain) and function (KOOS-PS) 1 year after TKA. Prospectively collected monocentric data on patients who underwent primary TKA were retrospectively reviewed. Multivariable logistic regression assessed the influence of BMI and weight change on outcomes while controlling for confounding variables. Outcomes included prolonged length of stay (LOS >3 days), nonhome discharge, 90-day readmission rate, satisfaction, and achievement of MCID for KOOS-Pain and KOOS-PS. Preoperative weight change had no impact on prolonged LOS (gain, p = 0.173; loss, p = 0.599). Preoperative weight loss was associated with increased risk of nonhome discharge (odds ratio [OR]: 1.47, p = 0.003). There was also increased risk of 90-day readmission with preoperative weight gain (OR: 1.27, p = 0.047) and decreased risk with weight loss (OR: 0.73, p = 0.033). There was increased risk of nonhome discharge with obesity class II (OR: 1.6, p = 0.016) and III (OR: 2.21, p < 0.001). Weight change was not associated with failure to achieve satisfaction, MCID in KOOS-Pain, or MCID in KOOS-PS. Obesity class III patients had decreased risk of failure to reach MCID in KOOS-Pain (OR: 0.43, p = 0.005) and KOOS-PS (OR: 0.7, p = 0.007). Overall, pre- and postoperative weight change has little impact on the achievement of satisfaction and clinically relevant differences in pain and function at 1 year. However, preoperative weight gain was associated with a higher risk of 90-day readmissions after TKA. Furthermore, patients categorized in Class III obesity were at increased risk of nonhome discharge but experienced a greater likelihood of achieving MCID in KOOS-Pain and KOOS-PS. Our results raise awareness of the dangers of using weight changes and BMI alone as a measure of TKA eligibility.

A Longitudinal Analysis of Weight Changes before and after Total Knee Arthroplasty: Weight Trends, Patterns, and Predictors

Longitudinal data on patient trends in body mass index (BMI) and the proportion that gains or loses significant weight before and after total knee arthroplasty (TKA) are scarce. This study aimed to observe patients longitudinally for a 2-year period and determine (1) clinically significant BMI changes during the 1 year before and 1 year after TKA and (2) identify factors associated with clinically significant weight changes.A prospective cohort of 5,388 patients who underwent primary TKA at a tertiary health care institution between January 2016 and December 2019 was analyzed. The outcome of interests was clinically significant weight changes, defined as a ≥5% change in BMI, during the 1-year preoperative and postoperative periods, respectively. Patient-specific variables and demographics were assessed as potential predictors of weight change using multinomial logistic regression.Overall, 47% had a stable weight throughout the study period (preoperative: 17% gained, 15% lost weight; postoperative: 19% gained, 16% lost weight). Patients who were older (odds ratio [OR] = 0.95), men (OR = 0.47), overweight (OR = 0.36), and Obese Class III (OR = 0.06) were less likely to gain weight preoperatively. Preoperative weight loss was associated with postoperative weight gain 1 year after TKA (OR = 3.03). Preoperative weight gain was associated with postoperative weight loss 1 year after TKA (OR = 3.16).Most patients maintained a stable weight before and after TKA. Weight changes during the 1 year before TKA were strongly associated with reciprocal rebounds in BMI postoperatively, emphasizing the importance of ongoing weight management during TKA and the recognition of patients at higher risk for weight gain.Level of evidence II (prospective cohort study).

2023 American College of Rheumatology and American Association of Hip and Knee Surgeons Clinical Practice Guideline for the Optimal Timing of Elective Hip or Knee Arthroplasty for Patients With Symptomatic Moderate-to-Severe Osteoarthritis or Advanced Symptomatic Osteonecrosis With Secondary Arthritis for Whom Nonoperative Therapy Is Ineffective

OBJECTIVE

To develop evidence-based consensus recommendations for the optimal timing of hip and knee arthroplasty to improve patient-important outcomes including, but not limited to, pain, function, infection, hospitalization, and death at 1 year for patients with symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis of the hip or knee who have previously attempted nonoperative therapy, and for whom nonoperative therapy was ineffective, and who have chosen to undergo elective hip or knee arthroplasty (collectively referred to as TJA).

METHODS

We developed 13 clinically relevant population, intervention, comparator, outcomes (PICO) questions. After a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the quality of evidence (high, moderate, low, or very low), and evidence tables were created. A Voting Panel, including 13 physicians and patients, discussed the PICO questions until consensus was achieved on the direction (for/against) and strength (strong/conditional) of the recommendations.

RESULTS

The panel conditionally recommended against delaying TJA to pursue additional nonoperative treatment including physical therapy, nonsteroidal antiinflammatory drugs, ambulatory aids, and intraarticular injections. It conditionally recommended delaying TJA for nicotine reduction or cessation. The panel conditionally recommended delay for better glycemic control for patients who have diabetes mellitus, although no specific measure or level was identified. There was consensus that obesity by itself was not a reason for delay, but that weight loss should be strongly encouraged, and the increase in operative risk should be discussed. The panel conditionally recommended against delay in patients who have severe deformity or bone loss, or in patients who have a neuropathic joint. Evidence for all recommendations was graded as low or very low quality.

CONCLUSION

This guideline provides evidence-based recommendations regarding the optimal timing of TJA in patients who have symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis for whom nonoperative therapy was ineffective to improve patient-important outcomes, including pain, function, infection, hospitalization, and death at 1 year. We acknowledge that the evidence is of low quality primarily due to indirectness and hope future research will allow for further refinement of the recommendations.

2023 American College of Rheumatology and American Association of Hip and Knee Surgeons Clinical Practice Guideline for the Optimal Timing of Elective Hip or Knee Arthroplasty for Patients With Symptomatic Moderate-to-Severe Osteoarthritis or Advanced Symptomatic Osteonecrosis With Secondary Arthritis for Whom Nonoperative Therapy Is Ineffective

OBJECTIVE

To develop evidence-based consensus recommendations for the optimal timing of hip and knee arthroplasty to improve patient-important outcomes including, but not limited to, pain, function, infection, hospitalization, and death at 1 year for patients with symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis of the hip or knee who have previously attempted nonoperative therapy, and for whom nonoperative therapy was ineffective, and who have chosen to undergo elective hip or knee arthroplasty (collectively referred to as TJA).

METHODS

We developed 13 clinically relevant population, intervention, comparator, outcomes (PICO) questions. After a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the quality of evidence (high, moderate, low, or very low), and evidence tables were created. A Voting Panel, including 13 physicians and patients, discussed the PICO questions until consensus was achieved on the direction (for/against) and strength (strong/conditional) of the recommendations.

RESULTS

The panel conditionally recommended against delaying TJA to pursue additional nonoperative treatment including physical therapy, nonsteroidal antiinflammatory drugs, ambulatory aids, and intraarticular injections. It conditionally recommended delaying TJA for nicotine reduction or cessation. The panel conditionally recommended delay for better glycemic control for patients who have diabetes mellitus, although no specific measure or level was identified. There was consensus that obesity by itself was not a reason for delay, but that weight loss should be strongly encouraged, and the increase in operative risk should be discussed. The panel conditionally recommended against delay in patients who have severe deformity or bone loss, or in patients who have a neuropathic joint. Evidence for all recommendations was graded as low or very low quality.

CONCLUSION

This guideline provides evidence-based recommendations regarding the optimal timing of TJA in patients who have symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis for whom nonoperative therapy was ineffective to improve patient-important outcomes, including pain, function, infection, hospitalization, and death at 1 year. We acknowledge that the evidence is of low quality primarily due to indirectness and hope future research will allow for further refinement of the recommendations.

2023 American College of Rheumatology and American Association of Hip and Knee Surgeons Clinical Practice Guideline for the Optimal Timing of Elective Hip or Knee Arthroplasty for Patients With Symptomatic Moderate-to-Severe Osteoarthritis or Advanced Symptomatic Osteonecrosis With Secondary Arthritis for Whom Nonoperative Therapy Is Ineffective

OBJECTIVE

To develop evidence-based consensus recommendations for the optimal timing of hip and knee arthroplasty to improve patient-important outcomes including, but not limited to, pain, function, infection, hospitalization, and death at 1 year for patients with symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis of the hip or knee who have previously attempted nonoperative therapy, and for whom nonoperative therapy was ineffective, and who have chosen to undergo elective hip or knee arthroplasty (collectively referred to as TJA).

METHODS

We developed 13 clinically relevant population, intervention, comparator, outcomes (PICO) questions. After a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the quality of evidence (high, moderate, low, or very low), and evidence tables were created. A Voting Panel, including 13 physicians and patients, discussed the PICO questions until consensus was achieved on the direction (for/against) and strength (strong/conditional) of the recommendations.

RESULTS

The panel conditionally recommended against delaying TJA to pursue additional nonoperative treatment including physical therapy, nonsteroidal antiinflammatory drugs, ambulatory aids, and intraarticular injections. It conditionally recommended delaying TJA for nicotine reduction or cessation. The panel conditionally recommended delay for better glycemic control for patients who have diabetes mellitus, although no specific measure or level was identified. There was consensus that obesity by itself was not a reason for delay, but that weight loss should be strongly encouraged, and the increase in operative risk should be discussed. The panel conditionally recommended against delay in patients who have severe deformity or bone loss, or in patients who have a neuropathic joint. Evidence for all recommendations was graded as low or very low quality.

CONCLUSION

This guideline provides evidence-based recommendations regarding the optimal timing of TJA in patients who have symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis for whom nonoperative therapy was ineffective to improve patient-important outcomes, including pain, function, infection, hospitalization, and death at 1 year. We acknowledge that the evidence is of low quality primarily due to indirectness and hope future research will allow for further refinement of the recommendations.

Patient-Reported Outcome Measures: State of the Art in Patient-Reported Outcome Measure Application in Lower Extremity Orthopaedics

With an increasing shift toward a value-based and outcome-driven healthcare system, patient-reported outcome measures (PROMs) will continue to play a prominent role in assessing performance, making clinical decisions, shared decision making, and determining the comparative effectiveness of procedures such as total joint arthroplasty for lower extremity conditions, such as ankle, hip, and knee osteoarthritis. As the application of PROMs in evaluating surgical outcomes has evolved from that of a research setting to that of a clinical setting, their use in the decision-making process has become more prevalent. As a result, preoperative optimization, surgical indications, and improved outcomes after surgery have been greatly enhanced. To enable benchmarking, quality reporting, and performance measurement at an aggregate level, it is crucial to have a comprehensive PROM collection system. However, achieving this goal is contingent upon addressing the variability in reported PROMs and the patient-centered benchmarks used to analyze clinical significance.

Go Big or Go Home: Obesity and Total Joint Arthroplasty

Obesity is highly prevalent, and it is expected to grow considerably in the United States. The association between obesity and an increased risk of complications following total joint arthroplasty (TJA) is widely accepted. Many believe that patients with body mass index (BMI) >40 have complications rates that may outweigh the benefits of surgery and should consider delaying it. However, the current literature on obesity and outcomes following TJA is observational, very heterogeneous, and full of confounding variables. BMI in isolation has several flaws and recent literature suggests shifting from an exclusively BMI <40 cutoff to considering 5 to 10% preoperative weight loss. BMI cutoffs to TJA may also restrict access to care to our most vulnerable, marginalized populations. Moreover, only roughly 20% of patients instructed to lose weight for surgery are successful and the practice of demanding mandatory weight loss needs to be reconsidered until convincing evidence exists that supports risk reduction as a result of preoperative weight loss. Obese patients can benefit greatly from this life-changing procedure. When addressing the potential difficulties and by optimizing preoperative assessment and intraoperative management, the surgery can be conducted safely. A multidisciplinary patient-centered approach with patient engagement, shared decision-making, and informed consent is recommended.

Validation of a Smartphone-Based Institutional Electronic Data Capture System for Thumb Carpometacarpal Joint Arthroplasty

BACKGROUND

The Orthopaedic Minimal Data Set (OrthoMiDaS) Episode of care (OME) is a prospectively collected database enabling capture of patient and surgeon-reported data in a more efficient, comprehensive, and dependable manner than electronic medical record (EMR) review. We aimed to assess and validate the OME as a data capture tool for carpometacarpal (CMC) arthroplasty compared to traditional EMR-based review. Specifically, we aimed to: (1) compare the completeness of the OME versus EMR data; and (2) evaluate the extent of agreement between the OME and EMR data-based datasets for carpometacarpal (CMC) arthroplasty.

METHODS

The first 100 thumb CMC arthroplasties after OME inception (Febuary, 2015) were included. Blinded EMR-based review of the same cases was performedfor 48 perioperative variables and compared to their OME-sourced counterparts. Outcomes included completion rates and agreement measures in OME versus EMR-based control datasets.

RESULTS

The OME demonstrated superior completion rates compared to EMR-based retrospective review. There was high agreement between both datasets where 75.6% (34/45) had an agreement proportion of >0.90% and 82.2% (37/45) had an agreement proportion of >0.80. Over 40% of the variables had almost perfect to substantial agreement (κ > 0.60). Among the 6 variables demonstrating poor agreement, the surgeon-inputted OME values were more accurate than the EMR-based review control.

CONCLUSIONS

This study validates the use of the OME for CMC arthroplasty by illustrating that it is reliably able to match or supersede traditional chart review for data collection; thereby offering a high-quality tool for future CMC arthroplasty studies.

Does body mass index influence improvement in patient reported outcomes following total knee arthroplasty? A retrospective analysis of 3918 cases

PURPOSE

The study aimed to determine whether body mass index (BMI) classification for patients undergoing total knee arthroplasty (TKA) is associated with differences in mean patient reported outcome measure (PROM) score improvements across multiple domains-including pain, functional status, mental health, and global physical health. We hypothesized that patients with larger BMIs would have worse preoperative and postoperative PROM scores, though improvements in scores would be comparable between groups.

MATERIALS AND METHODS

Patients undergoing primary TKA from 2018 to 2021 were retrospectively reviewed and stratified into four groups: Normal Weight; 18.5-25 kg/m², Overweight; 25.01-30 kg/m², Obese; 30.01-40 kg/m², and Morbidly Obese > 40 kg/m². Preoperative, postoperative, and pre/post-changes (Δ) in knee injury and osteoarthritis, joint replacement (KOOS, JR) and Patient-Reported Outcome Measurement Information System (PROMIS) measures of pain intensity, pain interference, physical function, mobility, mental health, and physical health were compared. Multivariate linear regression was used to assess for confounding comorbid conditions.

RESULTS

In univariate analysis, patients with larger BMIs had worse scores for KOOS, JR and all PROMIS metrics preoperatively. Postoperatively, scores for KOOS, JR and PROMIS pain interference, mobility, and physical health were statistically worse in higher BMI groups, though differences were not clinically significant. Morbidly obese patients achieved greater pre/post-Δ improvements in KOOS, JR and global physical health scores. Multivariate regression analysis showed high BMI was independently associated with greater pre/post-Δ improvements in KOOS, JR and global health scores.

CONCLUSION

Obese patients report worse preoperative scores for function and health, but greater pre/post-Δ improvements in KOOS, JR and physical health scores following TKA. Quality of life benefits of TKA in obese patients should be a factor when assessing surgical candidacy.

Is High Body Mass Index Protective or Detrimental in Surgical Fixation of Hip Fractures?: A Spline Regression Analysis of 22,388 Patients

OBJECTIVE

We aimed to characterize the association between BMI as a continuous variable and 30-day postoperative outcomes following hip fracture surgery through (1) 30-day readmission and reoperation; (2) local wound-related; and (3) systemic complications.

METHODS

The National Surgical Quality Improvement Program database (January 2016-December 2019) was queried for patients undergoing hip fracture open reduction and internal fixation. Baseline patient demographics, comorbidities, and patient outcomes were recorded. Multivariable regression models accounted for baseline demographics, comorbidities, and fracture patterns. Significant associations were analyzed using spline regression models to evaluate the continuous association between BMI and the aforementioned outcomes.

RESULTS

Spline models demonstrated a U-shaped curve for the odds of 30-day readmission and 30-day reoperation with nadirs at the BMI of 27.5 and 22.0 kg/m 2 . The odd ratios of superficial infection, deep infection, any wound complication, and inability to weight bear on POD 1 rose progressively starting at a BMI of 25.6, 35.5, 25.6, and 32.7 kg/m 2 respectively. Odds of 30-day mortality, transfusion, pneumonia, and delirium were greatest at the lowest recorded BMI (11.9 kg/m 2 ).

CONCLUSION

BMI has a U-shaped association with 30-day readmission and reoperation. Conversely, the highest risk of mortality and systemic complications (transfusion, pneumonia, and delirium) were within the lower BMI range, with diminishing risk as BMI increased. Local wound complications and systemic sepsis exhibited a third unique pattern with progressive rise in odds as BMI increased. The odds of any complications demonstrated a U-shaped pattern with a nadir in the overweight to obese I categories, suggesting that patients may be at lowest risk within this range.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Impact of Metabolic Syndrome and Obesity on Perioperative Total Joint Arthroplasty Outcomes: The Obesity Paradox and Risk Assessment in Total Joint Arthroplasty

Background

The relationship between elevated body mass index (BMI) and adverse outcomes in joint arthroplasty is well established in the literature. This paper aims to challenge the conventional thought of excluding patients from a total knee or hip replacement based on BMI alone. Instead, we propose using the metabolic syndrome (MetS) and its defining components to better identify patients at high risk for intraoperative and postoperative complications.

Methods

Patients who underwent primary, elective total knee and total hip arthroplasty were identified in the 2015-2020 American College of Surgeons National Surgical Quality Improvement Program database. Several defining components of MetS, such as hypertension, diabetes, and obesity, were compared to a metabolically healthy cohort. Postoperative outcomes assessed included mortality, length of hospital stay, 30-day surgical and medical complications, and discharge.

Results

The outcomes of 529,737 patients from the American College of Surgeons National Surgical Quality Improvement Program who underwent total knee and total hip arthroplasty were assessed. MetS is associated with increased complications and increased mortality. Both hypertension and diabetes are associated with increased complications but have no impact on mortality. Interestingly, while obesity was associated with increased complications, there was a significant decrease in mortality.

Conclusions

Our results show that the impact of MetS is more than the sum of its constitutive parts. Additionally, obese patients experience a protective effect, with lower mortality than their nonobese counterparts. This study supports moving away from strict BMI cutoffs alone for someone to be eligible for an arthroplasty surgery and offers more granular data for risk stratification and patient selection.

Can extant comorbidity indices identify patients who experience poor outcomes following total joint arthroplasty?

INTRODUCTION

It is uncertain if generic comorbidity indices commonly used in orthopedics accurately predict outcomes after total hip (THA) or knee arthroplasty (TKA). The purpose of this study was to determine the predictive ability of such comorbidity indices for: (1) 30-day mortality; (2) 30-day rate of major and minor complications; (3) discharge disposition; and (4) extended length of stay (LOS).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was retrospectively reviewed for all patients who underwent elective THA (n = 202,488) or TKA (n = 230,823) from 2011 to 2019. The American Society of Anesthesiologists (ASA) physical status classification system score, modified Charlson Comorbidity Index (mCCI), Elixhauser Comorbidity Measure (ECM), and 5-Factor Modified Frailty Index (mFI-5) were calculated for each patient. Logistic regression models predicting 30-day mortality, discharge disposition, LOS greater than 1 day, and 30-day major and minor complications were fit for each index.

RESULTS

The ASA classification (C-statistic = 0.773 for THA and TKA) and mCCI (THA: c-statistic = 0.781; TKA: C-statistic = 0.771) were good models for predicting 30-day mortality. However, ASA and mCCI were not predictive of major and minor complications, discharge disposition, or LOS. The ECM and mFI-5 did not reliably predict any outcomes of interest.

CONCLUSION

ASA and mCCI are good models for predicting 30-day mortality after THA and TKA. However, similar to ECM and mFI-5, these generic comorbidity risk-assessment tools do not adequately predict 30-day postoperative outcomes or in-hospital metrics. This highlights the need for an updated, data-driven approach for standardized comorbidity reporting and risk assessment in arthroplasty.

Demographic and Socioeconomic Determinants Are Associated with Poor Preoperative Patient-Reported Pain and Function in Primary TKA: A Cohort Study of 14,079 Patients

BACKGROUND

Pain and function, as reflected by patient-reported outcome measures (PROMs), can influence improvement after total knee arthroplasty (TKA) and can reflect the extent of patient access to orthopaedic surgical care. We aimed to (1) categorize patients according to pain and function PROM phenotypes, (2) identify patient characteristics associated with poor preoperative pain and function, and (3) assess relationships between baseline characteristics and PROM phenotypes.

METHODS

A prospective cohort of 14,079 TKAs was enrolled. Demographics, comorbidities, surgical details, and preoperative PROMs were collected. Outcomes included preoperative Knee injury and Osteoarthritis Outcome Score (KOOS) Pain (P) and Physical Function (PS) subscores, stratified by demographics. Patients were then categorized into 4 PROM phenotypes defined on the basis of the cohort medians: above or equal to the median for both pain and function scores (P+PS+), below the median for both pain and function (P-PS-), above or equal to the median for pain but below the median for function (P+PS-), and below the median for pain but above or equal to the median for function (P-PS+). Descriptive statistics and multivariable regression analyses were calculated.

RESULTS

The largest PROM phenotype was P-PS- (39.4%), followed by P+PS+ (38.9%). The cohort with discordantly poor function but high pain scores (less pain) was the smallest cohort (9.9%). Preoperative KOOS-Pain and KOOS-PS scores at or below the 25th percentile were independently associated with younger age, female sex, higher body mass index (BMI), non-White race, current smoking, lower education, non-commercial insurance, and higher Charlson Comorbidity Index (CCI). Multivariate logistic regression showed that patients in the P+PS+ category were older (odds ratio [OR] = 1.56), were more likely to be male (OR = 2.00), had a lower BMI (OR = 0.67), had more education (OR = 1.63), had a lower CCI, and were less likely to be Black (OR = 0.80) or Other (OR = 0.62) race, be a current smoker (OR = 0.62), and have commercial insurance (OR = 0.74), compared with the P-PS- phenotype.

CONCLUSIONS

Younger age, obesity, non-White race, female sex, current or recent smoking, non-commercial insurance, and higher CCI were associated with worse pre-TKA PROMs and poor pain-function phenotype combinations. Such a pattern may indicate barriers to TKA access among these patient populations leading to advanced levels of impairment at the time of treatment.

LEVEL OF EVIDENCE

Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Opioid and Sedative NarxCare Scores Greater Than 300 Are Associated With Adverse Outcomes After Nonemergent Spine Surgery

STUDY DESIGN

This was a prospectively captured cohort study.

OBJECTIVE

To explore associations between the preoperative opioid-specific NarxCare Scores (NCS) (NCS-opioids) as well as sedative-specific NCS (NCS-sedatives) as measures of patients' prescription drug use and (1) 90-day postoperative readmission; (2) ED visits; (3) reoperation; (4) prolonged (>2 d) hospital length of stay (LOS); and (5) nonhome discharge. In addition, we sought to evaluate the previously suggested 300+ threshold as a cutoff for moderate/high-risk designation.

BACKGROUND

The association between preoperative opioids and sedative use and healthcare utilization after nonemergent spine surgery is not well quantified. The NCS is a weighted scalar measure of opioids and sedatives that accounts for the number of prescribing providers, dispensing pharmacies, milligram equivalence doses, and overlapping prescription days.

METHODS

A total of 4680 nonemergent spine surgery cases were included. Preoperative NCS-opioids/sedatives were captured. Bivariate and multivariable regression models were constructed to analyze associations between NCS-opioids/sedatives ranges and outcomes while accounting for baseline differences. Spline regression and propensity score matching (PSM) analyses were also implemented.

RESULTS

For NCS-opioid, multivariable regression demonstrated higher odds of prolonged LOS starting in the 400 to 499 NCS-opioids category [odds ratio (OR): 1.44; 95% confidence interval (CI): 1.05-1.97; P =0.026] going into the 500+ category (OR: 1.94; 95% CI: 1.29-2.93; P =0.002]. The 500+ categories exhibited higher odds of 90-day readmission (OR: 1.77; 95% CI: 1.01-3.09; P =0.045). PSM comparison demonstrated that patients within the 300+ category had higher incidence of prolonged LOS [n=455 (44%) vs . n=537 (52%); P <0.001], 90-day readmission [n=118 (11%) vs . n=155 (15%); P =0.019] and 90-day reoperation [n=51 (4.9%) vs . n=74 (7.2%); P =0.042]. For NCS-sedative; there was higher odds of prolonged LOS (OR: 1.73; 95% CI: 1.14-2.63; P =0.010) and nonhome discharge(OR: 2.09; 95%CI: 1.22-3.63; P =0.008) within the 400 to 499 NCS-sedatives category. PSM comparison demonstrated significantly higher rates of prolonged LOS within the 300+ NCS-sedative cohort ( vs . scores <300), [n=277 (44%) vs. 319 (50%); P =0.021].

CONCLUSION

Spine surgery continues to advance toward patient-specific care. Higher NCS-opioids/sedatives values may predict up to a twofold increase in postoperative healthcare utilization. High values should prompt an interdisciplinary approach to mitigate deleterious prescription drug use.

The Association of Metabolic Syndrome on Complications and Implant Survivorship in Primary Total Knee Arthroplasty in Morbidly Obese Patients

BACKGROUND

Metabolic syndrome (MetS) includes interrelated conditions such as insulin resistance, abdominal obesity, hypertension, and dyslipidemia. This study sought to determine the association of MetS in morbidly obese patients (body mass index >40) on complications and clinical outcomes after primary total knee arthroplasty (TKA).

METHODS

A retrospective review was performed to include all morbidly obese patients who underwent primary elective TKA for osteoarthritis at a single academic institution. Patients who did and did not have MetS were propensity-matched 1:1 based on baseline characteristics. A total of 391 patients who did and 935 who did not have MetS were included having a mean body mass index of 44.2 (range, 40.0 to 68.9).

RESULTS

The MetS patients had longer lengths of stay (LOS) (3.5 ± 2.4 versus 3.0 ± 1.5 days, P = .001) and were more likely to be discharged to skilled nursing facilities (23.8 versus 15.3%, P = .007). At 90 days postoperatively, major (P = .756) and minor (P = .652) complication rates and readmissions (P = .359) were similar. Revision rates as well as improvements in KOOS-JR, and VR-12 mental and physical component scores from preoperative to 1 year (P = .856, P = .524, and P = .727, respectively) postoperatively did not significantly differ between groups. MetS and non-MetS patients had similar 5-year freedom from all-cause revision (90.2 versus 94.2%, P = .791).

CONCLUSION

Morbidly obese patients who have MetS had longer LOS and higher discharges to skilled nursing facilities. The 90-day complications, readmissions, revision rates, and patient-reported outcomes were similar, suggesting that resource allocation should be focused on perioperative protocols that can help optimize LOS and discharge dispositions in morbidly obese MetS patients undergoing TKA.

LEVEL OF EVIDENCE

III.

Preoperative Patient-Reported Outcome Measure Thresholds Should Not be Used for Indicating Total Knee Arthroplasty

BACKGROUND

While Medicare requires patient-reported outcome measures (PROMs) for many quality programs, some commercial insurers are requiring preoperative PROMs when determining eligibility for total knee arthroplasty (TKA). Concerns exist that these data may be used to deny TKA to patients above a specific PROM score, but the optimal threshold is unknown. We aimed to evaluate TKA outcomes based on theoretical PROM thresholds.

METHODS

We retrospectively analyzed 25,246 consecutive primary TKA patients from 2016 to 2019. Hypothesized preoperative knee injury and osteoarthritis outcome score for joint replacement cutoffs of 40, 50, 60, and 70 points were used. Preoperative scores below each threshold were considered "approved" surgery. Preoperative scores above each threshold were considered "denied" surgery. In-hospital complications, 90-day readmissions, and discharge disposition were evaluated. One-year minimum clinically important difference (MCID) achievement was calculated using previously validated anchor-based methods.

RESULTS

For "denied" patients below thresholds 40, 50, 60, and 70 points, 1-year MCID achievement was 88.3%, 85.9%, 79.6%, and 77%, respectively. In-hospital complication rates for approved patients were 2.2%, 2.3%, 2.1%, and 2.1%, while 90-day readmission rates were 4.6%, 4.5%, 4.3%, and 4.3%, respectively. Approved patients had higher MCID achievement rates (P < .001) for all thresholds but higher nonhome discharge rates than denied patients for thresholds 40 (P < .001), 50 (P = .002), and 60 (P = .024). Approved and denied patients had similar in-hospital complication and 90-day readmission rates.

CONCLUSION

Most patients achieved MCID at all theoretical PROMs thresholds with low complication and readmission rates. Setting preoperative PROM thresholds for TKA eligibility can help optimize patient improvement, but such a policy can create access to care barriers for some patients who would otherwise benefit from a TKA.

The Appropriateness of Preoperative Patient Reported Outcome Measures as an Indication for Total Hip Arthroplasty

BACKGROUND

While Medicare requires patient-reported outcome measures (PROMs) for many quality programs, some commercial insurers have begun requiring preoperative PROMs when determining patient eligibility for total hip arthroplasty (THA). Concerns exist these data may be used to deny THA to patients above a specific PROM score, but the optimal threshold is unknown. We aimed to evaluate outcomes following THA based on theoretical PROM thresholds.

METHODS

We retrospectively analyzed 18,006 consecutive primary THA patients from 2016-2019. Hypothesized preoperative Hip Disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS-JR) cutoffs of 40, 50, 60, and 70 points were used. Preoperative scores below each threshold were considered "approved" surgery. Preoperative scores above each threshold were considered "denied" surgery. In-hospital complications, 90-day readmissions, and discharge disposition were evaluated. HOOS-JR scores were collected preoperatively and 1-year postoperatively. Minimum clinically important difference (MCID) achievement was calculated using previously validated anchor-based methods.

RESULTS

Using preoperative HOOS-JR thresholds of 40, 50, 60, and 70 points, the percentage of patients who would have been denied surgery was 70.4%, 43.2%, 20.3%, and 8.3%, respectively. For these denied patients, 1-year MCID achievement was 75.9%, 69.0%, 59.1%, and 42.1%, respectively. In-hospital complication rates for approved patients were 3.3%, 3.0%, 2.8%, and 2.7%, while 90-day readmission rates were 5.1%, 4.4%, 4.2%, and 4.1%, respectively. Approved patients had higher MCID achievement (P < .001) but higher nonhome discharge (P = .01) and 90-day readmissions rates (P = .036) than denied patients.

CONCLUSION

Most patients achieved MCID at all theoretical PROM thresholds with low complication and readmission rates. Setting preoperative PROM thresholds for THA eligibility did not guarantee clinically successful outcomes.

Does Body Mass Index Influence the Outcomes and Survivorship of Modern Cementless Total Knee Arthroplasty?

BACKGROUND

Higher body mass index (BMI) has been associated with higher rates of aseptic loosening following cemented total knee arthroplasty (TKA). However, there is a paucity of evidence on the effect of BMI on the durability of modern cementless TKA. We aimed to assess the association between BMI and clinical outcomes following cementless TKA and to determine if there was a BMI threshold beyond which the risk of revision significantly increased.

METHODS

We identified 1,408 cementless TKAs of a modern design from an institutional registry. Patients were classified into BMI categories: normal (n = 136), overweight (n = 476), obese class I (n = 423), II (n = 258), and III (n = 115). The Knee Injury and Osteoarthritis Outcome Score for Joint Replacement and 12-item Short Form Health Survey scores were collected preoperatively and 2 years postoperatively. Survivorship was recorded at minimum 2 years (range, 24 to 88 months). BMI was analyzed as a continuous and categorical variable.

RESULTS

The improvement in patient-reported outcomes was similar across the groups. Thirty four knees (2.4%) were revised and 14 (1.0%) were for aseptic failure. Mean time-to-revision was 1.2 ± 1.3 years and did not differ across BMI categories (P = .455). Survivorship free from all-cause and aseptic revision was 97.1% and 99.0% at mean 4 years, respectively. Using Cox regression to control for demographics and bilateral procedures, BMI had no association with all-cause revision (P = .612) or aseptic revision (P = .186). Receiver operating characteristic curve analysis found no relationship between BMI and revision risk (c-statistic = 0.51).

CONCLUSION

BMI did not influence functional outcomes and survivorship of modern cementless TKA, possibly due to improved biological fixation at the bone-implant interface. Longer follow-up is necessary to confirm these findings.

Preoperative Veterans Rand-12 Mental Composite Score of < 40 Leads to Increased Healthcare Utilization and Diminished Improvement After Primary Knee Arthroplasty

BACKGROUND

Adverse outcomes after total knee arthroplasty (TKA) have been associated with preoperative psychological disorders and poor mental health. We aimed to investigate and quantify the association between preoperative mental health and 1) postoperative 90-day health care utilization; and 2) 1-year patient-reported outcomes after primary TKA.

METHODS

Retrospective review of prospectively collected data of patients who underwent primary elective TKA (n = 7,476) was performed. Preoperative mental health was evaluated using Veterans Rand-12 Mental Composite Scores (VR-12 MCS). Outcomes included prolonged length of stay (>2-days), nonhome discharge, 90-day readmissions, emergency department visits, and reoperation. Improvement in Knee Injury and Osteoarthritis Outcome Score (KOOS) and Patient Acceptable Symptom State (PASS) achievement were evaluated at 1-year. Multivariable regression was implemented to explore associations between preoperative VR-12 MCS and outcomes of interest.

RESULTS

A total of 5,402 (72.3%) completed 1-year follow-up. Lower preoperative VR-12 MCS was associated with higher odds of prolonged length of stay (MCS 20-39: odds ratio (OR): 1.46;P < .001), and nonhome discharge disposition (MCS 20-39: OR: 1.92;P < .001), but not 90-day readmission or reoperation (MCS20-39; P = .12 and P = .64). At 1-year, patients with a lower MCS were less likely to attain a substantial clinical benefit in KOOS-pain (MCS 0-19; OR: 0.25; P < .001) and less likely to achieve PASS (MCS20-39; OR: 0.74; P = .002). Patients with an MCS >60 were more likely to be discharged home (OR: 1.42; P = .008), achieve substantial clinical benefit in their KOOS-JR (OR: 1.16; P = .027),-Pain (OR: 1.220; P = .007) and PASS at 1-year (OR: 1.28; P = .008).

CONCLUSIONS

Lower VR-12 MCS is associated with increased postoperative health care utilization and worse patient-reported outcome measures at 1-year post-TKA. These findings suggest that a VR-12 MCS ≤40 could be used to designate increased risk, guide the preoperative discussion and potential interventions.

Impact of being underweight on peri-operative and post-operative outcomes of total knee or hip arthroplasty: A meta-analysis

BACKGROUND

Many systematic reviews have focused on assessing the effect of body mass index (BMI) on the outcomes and complications associated with total hip arthroplasty (THA) and total knee arthroplasty (TKA), but primarily dealt with obesity compared to normal weight (NW). None of these reviews attempted to assess the effect of low BMI or underweight (UW) compared to NW in patients undergoing THA or TKA.

AIM

This review aims to compare specific operative outcomes such as operation duration, length of hospital stay, and post-operative complications including mortality, infections, deep vein thrombosis, etc. along with re-hospitalization and reoperation rates between UW and NW patients undergoing THA, TKA or both.

METHODS

An electronic search was performed in PubMed, Scopus, Excerpta Medica database (EMBASE), Web of Science (WoS), and Cochrane Central Register of Controlled Trials (CENTRAL) along with a manual search. The quality of the studies was assessed using the Newcastle-Ottawa scale for cohort studies. The data were subjected to both qualitative and quantitative analysis.

RESULTS

Thirteen retrospective and five prospective cohort studies were included. The quality of included studies was assessed to be good to fair. The length of hospital stay after TKA or THA was found to be significantly higher for UW patients when compared to NW patients, with a mean difference: 0.39 95%CI: [0.06, 0.72], P = 0.02 (in days). Studies presenting both THA and TKA together as total joint arthroplasty showed an increased incidence of mortality in patients treated with THA or TKA alone, Odds ratio: 4.18 95%CI: [2.88, 6.07]. A higher incidence of post-operative complications was also observed in UW patients undergoing THA.

CONCLUSION

UW patients undergoing THA or TKA had a higher incidence of post-operative complications and were associated with a higher readmission rate. Moreover, UW patients were associated with an increased incidence of mortality in the studies that reported THA and TKA together.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Obesity trends over 10 years in primary hip and knee arthroplasty-a study of 12,000 patients

OBJECTIVES/AIMS

Obesity and its increasing prevalence are global public health concerns. Following joint replacement, there is evidence to support that obese patients are more likely to suffer complications. We examined 10-year trends in BMI of the primary total hip and total knee replacement cohorts in our institution to discern whether the BMI of these patients has changed over time.

METHODS

We examined BMI data of patients who underwent primary hip and knee arthroplasty from our institutional database from January 1, 2010 to December 31, 2019 (n = 12,169). We analysed trends in BMI over this period with respect to (i) surgical procedure, (ii) gender, and (iii) age categories.

RESULTS

The overall number of surgical procedures increased over the study period which meant more obese patients underwent surgery over time. Average BMI did not change significantly over time; however, there was a statistically significant increase in BMI in females aged < 45 in both arthroplasty groups.

CONCLUSION

The average BMI of patients undergoing primary hip and knee arthroplasty in our high-volume tertiary orthopaedic centre has remained relatively unchanged over the past 10 years; however, our local service is caring for a greater number of overweight/obese patients due to the increase in overall volume. This will have significant implications on health care expenditure and infrastructure going forward which further emphasises the importance of ongoing national obesity prevention strategies. The increase in BMI seen in females aged < 45 may mark an impending era of obese younger patients with end-stage osteoarthritis.

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.

Validation of a Novel Smartphone-Based Electronic Data Capture System Following Surgical Fixation of Distal Radial Fractures

BACKGROUND

Large prospective institutional data provide the opportunity to conduct level II and III studies using robust methodologies and adequately powered sample-sizes, while circumventing limitations of retrospective databases. We aimed to validate a prospective data collection tool, the Orthopaedic Minimal Data Set Episode of Care (OME), implemented at a tertiary North American health care system for distal radial fracture (DRF) open reduction and internal fixation (ORIF).

METHODS

The first 100 DRF ORIFs performed after OME inception (February 2015) were selected for this validation study. A blinded review of the operative notes and charts was performed, and extracted data of 75 perioperative DRF ORIF procedure variables were compared with OME collected data for agreement. Outcomes included completion rates and agreement measures in OME versus electronic medical record (EMR)-based control datasets. Data counts were evaluated using raw percentages and McNemar tests. Cohen (κ) and concordance correlation coefficient analyzed categorical and numerical variable agreement, respectively.

RESULTS

Overall, OME demonstrated superior completion and agreement parameters versus EMR-based retrospective review. Nine data points (12.0%) demonstrated significantly higher completion rates within the OME dataset (P < .05, each), and 88% (66/75) of captured variables demonstrated similar completion rates. Up to 80.0% (60/75) of variables either demonstrated an agreement proportion of ≥0.90 or were solely reported in the OME. Of 33 variables eligible for agreement analyses, 36.4% (12/33) demonstrated almost perfect agreement (κ > 0.80), and 63.6% (21/33) exhibited almost perfect or substantial agreement (κ > 0.60).

CONCLUSIONS

The OME is a valid and accurate prospective data collection tool for DRF ORIF that is reliably able to match or supersede traditional retrospective chart review. Future investigations could use this tool for large-scale analyses investigating peri/intraoperative DRF ORIF variables.

Factors Affecting 30-Day Mortality following Primary Elective Total Knee Arthroplasty: A Database Study of 326,157 Patients

Despite its rarity, the risk of mortality following primary elective total knee arthroplasty (TKA) is a critical component of surgical decision-making and patient counseling. The purpose of our study was to (1) determine the overall 30-day mortality rate for unilateral primary elective TKA patients, (2) determine the 30-day mortality rates when stratified by age, comorbidities, and preoperative diagnosis, and (3) identify the distribution of (i) patient demographics, (ii) baseline comorbidities, and (iii) preoperative diagnoses between mortality and mortality-free cohorts. A total of 326,157 patients underwent primary elective TKA (2011-2018) were identified through retrospective review of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Patients were divided into 30-day mortality (n = 320) and mortality-free (n = 325,837) cohorts. Patient demographics, preoperative comorbidities, and preoperative diagnoses were compared. Age group, American Society of Anesthesiology (ASA) score, and modified Charlson Comorbidity Index (CCI) scores were normalized per 1000 and stratified by preoperative diagnosis. The overall mortality rate was 0.098%. Older age (p < 0.001) and male gender (p < 0.001) were associated with increased mortality. There was no association between mortality and race (p = 0.346) or body mass index (BMI) class (p = 0.722). All reported comorbidities except smoking status were significantly greater in the mortality cohort (p < 0.05). For ASA scores of I, II, III, and IV, the number of deaths per 1,000 were 0.16, 0.47, 1.4, and 4.4, respectively. For CCI scores of 0, 1, 2, 3, 4, and 6, mortality rates per 1,000 were 0.76, 2.1, 7.0, 11, 29, and 7.6, respectively. Mortality rates for a preoperative diagnosis of osteoarthritis (OA) versus non-OA were, respectively, 0.096% and 0.19% (p < 0.001). Increased age, male gender, increased comorbidity burden, and non-OA preoperative diagnoses are associated with higher rates of 30-day postoperative mortality. There were no significant associations between BMI or race and 30-day mortality. These findings aid in identifying of higher-risk patients, who can then receive appropriate counseling or preoperative interventions to reduce the risk of perioperative mortality.

Surgical Complications After Reverse Total Shoulder Arthroplasty and Total Shoulder Arthroplasty in the United States

Shoulder arthroplasty has become popular in the treatment of degenerative shoulder conditions in the United States. Shoulder arthroplasty usage has expanded to younger patients with increased surgical indications.