Quality-Adjusted Life Years After Hip and Knee Arthroplasty: Health-Related Quality of Life After 12,782 Joint Replacements

Similar QALY gain in primary and revision knee arthroplasty: A cost analysis and Markov model

PURPOSE

The aim of this study is to investigate the cost-effectiveness of revision total knee arthroplasty compared to primary total knee arthroplasty in terms of cost-per-quality-adjusted life year (QALY).

METHODS

Data were retrieved for all primary and revision total knee replacement (TKA) procedures performed at a tertiary Swiss hospital between 2006 and 2019. A Markov model was created to evaluate revision risk and we calculated lifetime QALY gain and lifetime procedure costs through individual EuroQol 5 dimension (EQ-5D) scores, hospital costs, national life expectancy tables and standard discounting processes. Cost-per-QALY gain was calculated for primary and revision procedures.

RESULTS

EQ-5D data were available for 1343 primary and 103 revision procedures. Significant QALY gains were seen following surgery in all cases. Similar, but significantly more QALYs were gained following primary TKA (PTKA) (5.67 ± 3.98) than following revision TKA (RTKA) (4.67 ± 4.20). Cost-per-QALY was €4686 for PTKA and €10,364 for RTKA. The highest average cost-per-QALY was seen in two-stage RTKA (€12,292), followed by one-stage RTKA (€8982).

CONCLUSION

RTKA results in a similar QALY gain as PTKA. The costs of achieving health gain are two to three times higher in RTKA, but both procedures are highly cost-effective.

LEVEL OF EVIDENCE

Economic level II.

Development and validation of a machine learning model to improve precision prediction for irrational prescriptions in orthopedic perioperative patients

OBJECTIVE

Our objective was to develop a machine learning model capable of predicting irrational medical prescriptions precisely within orthopedic perioperative patients.

METHODS

A dataset comprising 3047 instances of suspected irrational medication prescriptions was collected from a sample of 1318 orthopedic perioperative patients from April 2019 to March 2022. Four machine learning models were employed to forecast irrational prescriptions, following which, the performance of each model was meticulously assessed. Subsequently, a thorough variable importance analysis was conducted on the model that performed the best predictive capabilities. Thereafter, the efficacy of integrating this optimal model into the existing audit prescription process was rigorously evaluated.

RESULTS

Of the models utilized in this study, the RF model yielded the highest AUC of 92%, whereas the NB model presented the lowest AUC of 68%. Also, the RF model boasted the most robust performance in terms of PPV, reaching 82.4%, and NPV, reaching 86.6%. The ANN and the XGBoost model were neck and neck, with the ANN slightly edging out with a higher PPV of 95.9%, while the XGBoost model boasted an impressive NPV of 98.2%. The RF model singled out the following five factors as the most influential in predicting irrational prescriptions: the type of drug, the type of surgery, the number of comorbidities, the date of surgery after hospitalization, as well as the associated hospital and drug costs.

CONCLUSION

The RF model showcased significantly high level of proficiency in predicting irrational prescriptions among orthopedic perioperative patients, outperforming other models by a considerable margin. It effectively enhanced the efficiency of pharmacist interventions, displaying outstanding performance in assisting pharmacists to intervene with irrational prescriptions.

Comparison of current relative value unit-based prices and utility between common surgical procedures, including orthopedic surgeries, in South Korea

BACKGROUND

The medical pricing system strongly influences physicians' job satisfaction and patient health outcomes. This study aimed to investigate the current relative value unit (RVU)-based pricing and utility of patients in commonly performed surgical procedures in South Korea.

METHODS

Fifteen common surgical procedures were selected from OECD statistics, and three additional orthopedic procedures were examined. The current pricing of each surgical procedure was retrieved from the Korea National Health Insurance Service, and the corresponding utilities were obtained as quality-adjusted life year (QALY) gains from previous studies. The relationship between the current prices (RVUs) and the patients' utility (incremental QALY gains/year) was analyzed. Subgroup analysis was performed between fatal and non-fatal procedures and between orthopedic and non-orthopedic procedures.

RESULTS

A significant negative correlation (r = - 0.558, p < 0.001) was observed between RVU and incremental QALY among all 18 procedures. The fatal subgroup had a significantly higher RVU than the non-fatal subgroup (p < 0.05), while the former had a significantly lower incremental QALY than the latter (p < 0.001). Orthopedic procedures showed higher incremental QALY values than non-orthopedic procedures, but they did not show higher prices (RVU).

CONCLUSIONS

This paradoxical relationship between current prices and patient utility is attributed to the higher pricing of surgical procedures for fatal and urgent conditions. Orthopedic surgery has been found to be a cost-effective treatment strategy. These findings could contribute to a better understanding of the potential role of incremental QALY in pursuing value-based purchasing or reasonable modification of the current medical fee schedule.

Biofilm and How It Relates to Prosthetic Joint Infection

Prosthetic joint infection following total joint arthroplasty is a devastating complication, resulting in increased morbidity and mortality for the patient. The formation of a biofilm on implanted hardware contributes to the difficulty in successful identification and eradication of the infection. Antibiotic therapy and surgical intervention are necessary for addressing this condition; we present a discussion on different treatment options, including those that are not yet routinely utilized in the clinical setting or are under investigation, to highlight the present and future of PJI management.

Factors Correlated with the Quality of Life after Total Knee Arthroplasties: A Literature Review

Introduction

Total Knee Arthroplasty (TKA) has been widely reported to improve outcomes and quality of life (QoL) in patients with knee osteoarthritis (KOA), but there are still 15 - 20% of patients still experience pain, physical limitations, and other complications after TKA. Therefore, it is necessary to identify various factors that correlate with QoL from current evidence. The objective is to review the literature on factors that correlate with QoL in patients who underwent TKA.

Materials and methods

A literature search was conducted on five databases, i.e. ProQuest, CINAHL, Medline, Embase, and Scopus, using the following keywords: total knee arthroplasty (TKA), post-operative, quality of life (QoL), and outcome. There were no restrictions on the research design.

Results

This review found 14 articles (7 prospective studies and 7 retrospective studies) involving 15,972 patients who underwent TKA, with an age range of 32 - 94 years. All articles reported improvement in QoL after TKA. The review revealed 30 factors, of which 15 factors were significantly correlated with QoL after TKA. The factors were grouped into four types: demographic, socioeconomic, clinical, and psychosocial factors.

Conclusion

Information regarding factors that correlate with QoL after TKA can be used for directing treatment and discharge planning according to the patient's factors.

What Is the Safest Intersurgical Interval between Staged Bilateral Total Knee Arthroplasty? A Nationwide Analysis of 20,279 Patients

In staged bilateral total knee arthroplasty (BTKA), the intersurgical time is yet to be determined. This study aimed to (1) test for differences in in-hospital metrics between the index and contralateral TKA and (2) determine the safest intersurgical time interval to minimize adverse outcomes after the contralateral surgery. The National Readmissions Database was queried for patients who received staged BTKA (2016-2017). A total of 20,279 patients were included. Demographics, comorbidities, baseline determinants, and intersurgical time between index and contralateral TKAs (≤ 3 month, 4-6 months, 7-9 months, and 10-12 months intervals) were captured. Outcomes included healthcare utilization (length of stay [LOS] and nonhome discharge), in-hospital costs, and in-hospital complications. Outcomes were compared between index versus contralateral surgeries and among contralateral surgeries of various intersurgical intervals. Contralateral surgeries had shorter LOS (2.2 ± 1.9 vs. 2.4 ± 2.0 days; p < 0.001), lower nonhome discharge (n = 2692[13.2%] vs. n = 2963[14.7%]; p = 0.001), and in-hospital costs ($16,476 ± $7,404 vs. 16,774 ± $9,621; p < 0.001), but similar rates of nonmechanical (p = 0.40) complications compared with index TKA. Multivariable regression demonstrated that intersurgical time was not associated with nonmechanical complications or transfusion, or 30-day readmission (p > 0.05, each). Compared with the less than or equal to 3-month interval, the 4 to 6-month interval exhibited highest odds ratio (OR) of any infection (OR: 1.81; 95% confidence interval [CI]: [1.13-2.88]; p = 0.013), urinary tract infection (OR:1.81, 95%CI: [1.13-2.90]; p = 0.014), and any-cardiac complications (OR:1.17; 95%CI: [1.01-1.35]; p = 0.037). Patients in the 10-12-month cohort had lowest odds of posthemorrhagic anemia (OR: 0.84; 95% CI: [0.72-0.98]; p = 0.03). Overall, the second surgery of a staged BTKA has lower healthcare utilization despite similar complication rates. While patients in the 10 to 12-month intersurgical interval had the most favorable overall safety profile, no single interval exhibited consistently lower complications for all measured outcomes. Special care pathways should be optimized to care for patients undergoing staged BTKA.

Comparison of Pneumonia and Major Complications After Total Joint Arthroplasty With Spinal Versus General Anesthesia: A Propensity-matched Cohort Analysis

INTRODUCTION

Spinal anesthesia (SA) allows total joint arthroplasty to be done while minimizing opioids and systemic anesthetic agents compared with general anesthesia (GA). SA has been associated with shortened postoperative recovery; however, the relationship between SA, major postoperative complications, and pneumonia (PNA) remains unclear.

METHODS

Patients in a large, national database who underwent total hip arthroplasty or total knee arthroplasty from 2010 to 2020 were identified. 1:1 propensity score matching was used to create matched groups of patients who underwent SA and GA. The groups were matched by age, sex, chronic obstructive pulmonary disease, smoking status, Charlson Comorbidity Index, and American Society of Anesthesiology (ASA) classification. 1:1 matching was also done among the ASA classifications as a subanalysis.

RESULTS

Overall, equally matched groups of 217,267 patients who underwent SA versus GA were identified. 850 patients (0.39%) developed postoperative PNA after GA versus 544 patients (0.25%) after SA ( P < 0.001). The risk of major complications was 6,922 (3.2%) in the GA group and 5,401 (2.5%) in the SA group ( P < 0.001). Similarly, the risk of unplanned postoperative reintubation was higher (0.18% versus 0.10%, P < 0.001) and mortality was higher (0.14% versus 0.09%, P < 0.001) in the GA group than in the SA group. In ASA 1 to 3 patients, the risk of PNA was 0.08% to 0.21% higher with GA than with SA. In ASA 4 patients, the risk of PNA was 0.42% higher in SA than in GA (1.92% versus 1.5%, P < 0.001) and the mortality rate was nearly doubled in GA than in SA (1.46% versus 0.77%, P = 0.017).

DISCUSSION

Overall, GA was associated with a small but markedly higher rate of major complications, mortality, and PNA than SA in patients undergoing total joint arthroplasty when matching for differences in comorbidities. ASA 4 patients experienced the greatest increase in absolute risk of mortality with GA versus SA.

When Do We Perform Elective Total Knee Arthroplasty? General and Demographic-Specific Trends of Preoperative Pain and Function among 10,327 Patients

Total knee arthroplasty (TKA) is the sole disease-modifying intervention for end-stage osteoarthritis. However, the temporal trends and stratification of age and patient demographics of pain and function levels at which surgeons perform TKA have not been characterized. The present investigation aimed to analyze the temporal trends of preoperative pain and functional patient-reported outcomes measures (PROMs) over the past 5 years when stratifying patient demographics. A prospective cohort of all patients who underwent primary elective TKA between January 2016 and December 2020 at a North American integrated tertiary health care system was retrospectively reviewed. The primary outcome was quarterly baseline (preoperative) pain and function PROM values before primary elective TKA. Evaluated PROMs included Knee Osteoarthritis Outcome Score (KOOS)-pain and KOOS-physical function shortform (PS) for the 5-year study period and were stratified by patient demographics (age, sex, race, and body mass index [BMI]). A total of 10,327 patients were analyzed. Preoperative pain levels remained unchanged over the study period for patients in the 45- to 64-year category (P-trend = 0.922). Conversely, there was a significant improvement in preoperative pain levels in the 65+ years group. Sex-stratified trends between males and females did not demonstrate a significant change in pre-TKA baseline pain over the study period (P-trend = 0.347 and P-trend = 0.0744). Both white and black patients demonstrated consistent KOOS-pain levels throughout the study period (P-trend = 0.0855 and P-trend = 0.626). Only white patients demonstrated improving preoperative KOOS-PS (P-trend = 0.0001), while black and "other" patients demonstrated consistent lower preoperative functional levels throughout the study period (P-trend = 0.456 and P-trend = 0.871). All BMI categories demonstrated relatively consistent preoperative KOOS-pain and KOOS-PS except for overweight and obese patients who demonstrated progressive improvement in preoperative KOOS-PS over the study period. Patients and surgeons are electing to perform primary TKA at higher levels of preoperative function. Stratification by race showed black patients did not experience a similar trend of improving function and exhibited a consistently lower functional level versus white patients. This disparity is likely to be multifactorial but may indicate underlying barriers to TKA access.

Implant Selection Strategies for Total Joint Arthroplasty: The Effects on Cost Containment and Physician Autonomy

BACKGROUND

With continued declines in reimbursement for total joint arthroplasty, health systems have explored implant cost containment measures to generate sustainable margins. This review evaluated how implementation of (1) implant price control programs, (2) vendor purchasing agreements, and (3) bundled payment models affected implant costs and physician autonomy in implant selection.

METHODS

PubMed, EBSCOhost, and Google Scholar were searched to identify studies that evaluated the efficacy of total hip or total knee arthroplasty implant selection strategies. The review included publications between January 1, 2002, and October 17, 2022. The mean Methodological Index for Nonrandomized Studies score was 18.3 ± 1.8.

RESULTS

A total of 13 studies (32,197 patients) were included. All studies implementing implant price capitation programs found decreased implant costs, ranging 2.2 to 26.1% and increased utilization of premium implants. Most studies found bundled payments models reduced total joint arthroplasty implant costs with greatest reduction being 28.9%. Additionally, while absolute single vendor agreements had higher implant costs, preferred single vendor agreements had reduced implant costs. When given price constraints, surgeons tended to select more premium implants.

CONCLUSION

Alternative payment models that incorporated implant selection strategies saw reduced costs and surgeon utilization of premium implants. The study findings encourage further research on implant selection strategies, which must balance the goals of cost containment with physician autonomy and optimized patient care.

LEVEL OF EVIDENCE

Level III.

What is the association between gender and self-perceived health status when controlling for disease-specific conditions? A retrospective data analysis of pre- and post-operative EQ-5D-5L differences in total hip and knee arthroplasty

BACKGROUND

The self-perceived health status of patients undergoing total hip and knee arthroplasty (THA and TKA) might differ post-operatively due to gender, age, or comorbidities. Patient-reported outcome measures (PROMs) such as the EQ-5D-5L measure the self-perceived health status. This study investigates whether the index score of the EQ-5D-5L is a valid tool for interpreting gender differences in outcomes for patients undergoing THA and TKA.

METHODS

Routine and PROM-data of elective primary THA or TKA patients in two German hospitals between 2016 and 2018 were analyzed. Univariate analysis with Pearson's chi-square was conducted to identify control variables for gender. To quantify the association between gender and the EQ-5D-5L dimensions, a cumulative odds ordinal logistic regression with proportional odds was conducted.

RESULTS

Two thousand three hundred sixty-eight​​ THA patients (m = 978; f = 1390) and 1629 TKA patients (m = 715; f = 914) were considered. The regression analysis of the individual EQ-5D-5L dimensions showed that female gender was significantly associated with better self-care (THA and TKA) and better post-operative mobility (THA). In contrast, male gender was significantly associated with less pain/discomfort (TKA) and less anxiety/depression (THA) pre-surgery and 3-months post-surgery.

CONCLUSION

Our results confirmed that the self-perceived health status improved after surgery. However, due to the different associations of gender to the individual dimensions of the EQ-5D-5L, the weighted index score clouds the comparability between patients with different gender undergoing THA or TKA. Therefore, we argue to use the individual five dimensions for health status analysis, to reveal relevant additional information.

Cost-effectiveness of implant movement analysis in aseptic loosening after hip replacement: a health-economic model

OBJECTIVE

To investigate the cost-effectiveness of using Implant Movement Analysis (IMA) to follow up suspected aseptic loosening when the diagnosis after an initial X-ray is not conclusive, compared with a diagnostic pathway with X-ray follow-up.

METHODS

A health-economic model in the form of a decision tree was developed using quality-adjusted life years (QALY) from the literature, cost-per-patient data from a university hospital and the probabilities of different events from expert physicians' opinions. The base case incremental cost-effectiveness ratio (ICER) was compared with established willingness-to-pay thresholds and sensitivity analyses were performed to account for assumptions and uncertainty.

RESULTS

The base case ICER indicated that the IMA pathway was cost effective (SEK 99,681, compared with the SEK 500,000 threshold). In the sensitivity analysis, the IMA pathway remained cost effective during most changes in parameters. ICERs above the threshold value occurred in cases where a larger or smaller proportion of people receive immediate surgery.

CONCLUSION

A diagnostic pathway using IMA after an inconclusive X-ray for suspected aseptic loosening was cost effective compared with a pathway with X-ray follow-up.

30-Days to 10-Years Mortality Rates following Total Knee Arthroplasty: A Systematic Review and Meta-Analysis of the Last Decade (2011-2021)

Mortality data following primary total knee arthroplasty (TKA) beyond 1-year postoperative time period is sparse. This systematic review and meta-analysis aimed to: (1) estimate contemporary mortality rates at 30 days, 90 days, 1 year, 5 years, and 10 years following primary TKA; and (2) identify risk factors and causes of mortality following TKA. PubMed, MEDLINE, Cochrane, EBSCO host, and Google Scholar databases were queried from January 1, 2011 to October 30, 2021 for all studies reporting mortality rates following primary TKA. A meta-analysis of proportions was conducted using a random-effects model to ascertain pooled mortality rates (95% confidence interval [CI]). Meta-regression was utilized to account for confounding effects on mortality rates due to the study's country of origin, median date of study data, average patient age, and patient gender ratios, with a level of significance maintained at p-value <0.05. A total of 44 articles were included in quantitative synthesis. The pooled 30-day mortality rate was 0.14% (95% CI:0.05-0.22%; n = 1,817,647). The pooled 90-day mortality rate was 0.35% (95% CI:0.0.28-0.43%; n = 1,641,974). The pooled 1-year mortality rate was 1.1% (95% CI:0.71-1.49%; n = 1,178,698). The pooled 5-year mortality rate was 5.38% (95% CI:4.35-6.42%; n = 597,041). The pooled 10-year mortality rate was 10.18% (95% CI:7.78-12.64%; n = 815,901). Our 30-day mortality rate was lower than previously reported. The most common causes of death at all time points were due to cardiac disease, cerebrovascular disease, and malignancy. Obesity demonstrated mixed effects on long-term mortality rates. Overall mortality rates of TKA remain low worldwide at all time points and immediate postoperative mortality rates continue to fall. Compared to symptomatic knee osteoarthritic patients reported in the literature, TKA patients qualitatively exhibited lower mortality rates, which may support the value of TKA in improving quality of life without associated excess mortality. Future long-term mortality studies should be conducted to account for geographical variability in mortality rates and further elucidate modifiable risk factors associated with mortality among TKA patients.

The International Initiative to Measure Perceived Risk in Arthroplasty: The Results From a Multinational Survey

BACKGROUND

There is an inherent moral imperative to avoid complications from arthroplasty. Doing so at ideal cost is also associated with surgeon reputation, and, increasingly in health care delivery systems that measure and competitively score outcomes, reimbursement to the surgeons and their hospitals. As a result, patients who are perceived to be in higher risk comorbidity groups, such as the obese and diabetics, as well as those challenged by socioeconomic factors may face barriers to access elective arthroplasty.

METHODS

In this initiative, surveys were sent to surgeons in 8 different countries, each adapted for their own unique payment, remuneration, and punitive models. The questions in the surveys pertained to surgeons' perception of risk regarding medical and socioeconomic factors in patients indicated for total hip or knee arthroplasty. This paper primarily reports on the results from Canada, Ireland, and the United Kingdom.

RESULTS

The health care systems varied between a universal/state funded health care system (Canada) to those that were almost exclusively private (India). Some health care systems have "bundled" payment with retention of fees for postoperative complications requiring readmission/reoperation and including some with public publication of outcome data (United States and the United Kingdom), whereas others had none (Canada). There were some major discrepancies across different countries regarding the perceived risk of diabetic patients, who have variable Hemoglobin A1c cut-offs, if any used. However, overall the perception of risk for age, body mass index, age, sex, socioeconomic, and social situations remained surprisingly consistent throughout the health care systems. Any limitations set were primarily driven by surgeon decision making and not external demands.

CONCLUSION

Surgeons will understandably try and optimize the health status of patients who have reversible risks as shown by best available evidence. The evidence is of variable quality, and, especially for irreversible social risk factors, limited due to concerns over cost and quality outcomes that can be influenced by experience-driven perceptions of risk. The results show that perceptions of risk do have such influence on access across many health care delivery environments. The authors recommend better risk-adjustment models for medical and socioeconomic risk factors with possible stratification/exclusions regarding reimbursement adjustments and reporting to help reverse disparities of access to arthroplasty.

Long-term health-related quality of life of total hip arthroplasty patients and cost-effectiveness analysis in the Japanese universal health insurance system

AIM

Total hip arthroplasty can effectively improve patients' motility with end-stage osteoarthritis. This study aimed to: (1) compare gradual changes in utility values with total hip arthroplasty and estimated values without; (2) evaluate total hip arthroplasty cost-effectiveness; and (3) evaluate cost-effectiveness by age, diagnosis, and comorbidity.

METHODS

Patients who underwent total hip arthroplasty between January 2008 and December 2009 were included. Patients completed the EuroQol preoperatively and at 1, 3, 5 and 7 years postoperatively. To derive the quality-adjusted life years gained, a utility score was obtained from the EuroQol item scores and combined with 7 years, and estimates were obtained by discounting the postoperative 1-year utility value at an annual rate of 2%-4%. Mixed-effects regression models were used to compare the estimated and the measured utility values.

RESULTS

Mean total cost was 1,921,849 yen, and quality-adjusted life years gain score was 1.746 with per cost as 1,100,715 yen. Compared with actual measurements, the estimated values from 1 to 7 years post-surgery differed significantly, and interaction was observed. Regarding age, the older the patient, the higher the cost per quality-adjusted life years. Patients with lower preoperative physical function had higher quality-adjusted life years gains, while the cost per quality-adjusted life years was lower.

CONCLUSIONS

Total hip arthroplasty was cost-effective. Compared with actual measurements, the estimated utility values from 1 to 7 years post-surgery significantly differed. Even among older patients and those with impaired preoperative physical functions, its cost was lower than patients' willingness to pay in Japan.

Long-term outcomes of the Nexgen© posterior stabilized knee: minimum 15 year follow-safe and effective

PURPOSE

Studying long-term survivorship and functional outcomes for specific prostheses is critical for elucidating areas in need of design improvement. This study reports the long-term of the NexGen Posterior Stabilized (PS) Total Knee implant (TKA) (Zimmer Biomet, Warsaw IN) Performed by a single surgeon.

METHODS

Data from patients treated with the NexGen PS TKA between January 2003 and December 2005 with a minimal follow-up of 15 years was collected from a prospectively collected database. Survivorship rates and Oxford Knee Scores (OKS) were obtained for those patients available for follow-up.

RESULTS

Ninety-five patients met the inclusion criteria during the study period. OKS was available for 44 (46%) patients. Ten patients required revision surgery (10.52%). Implant-specific survivorship of all cases that were reviewed was 98%. Survivorship of implants in patients that we were able to reach, or deceased patients was 93%. The average Oxford Knee Score was 39.1 (14-48. SD ± 7.70) with 48 being the maximal score.

CONCLUSION

Despite some concerns about durability of this implant, good longevity and function was demonstrated. At a minimum of 15 years follow-up in this cohort. Given these results design features of this system should be considered for future generations of implants.

Cost-effectiveness of a novel, fluoroscopy-based robotic-assisted total hip arthroplasty system: A Markov analysis

BACKGROUND

The purpose of this study was to assess the cost-effectiveness of a novel, fluoroscopy-based robotic-assisted total hip arthroplasty (RA-THA) system compared to a manual unassisted technique (mTHA) up to 5 years post-operatively.

METHODS

A Markov model was constructed to compare the cost-effectiveness of RA-THA and mTHA. Cost-effectiveness was defined as an Incremental Cost-Effectiveness Ratio (ICER) <$50 000 or $100 000 per Quality Adjusted Life Year (QALY).

RESULTS

RA-THA patients experienced lower costs compared to mTHA patients at 1 year ($20 865.12 ± 9897.52 vs. $21 660.86 ± 9909.15; p < 0.001) and 5 years ($23 124.57 ± 10 045.48 vs. $25 756.42 ± 10 091.84; p < 0.001) post-operatively. RA-THA patients also accrued more QALYs (1-year: 0.901 ± 0.117 vs. 0.888 ± 0.114; p < 0.001; 5-years: 4.455 ± 0.563 vs. 4.384 ± 0.537 p < 0.001). Overall, RA-THA was cost-effective (1-year ICER: $-61 210.77; 5-year ICER: $-37 068.31).

CONCLUSIONS

The novel, fluoroscopy-based RA-THA system demonstrated cost-effectiveness when compared to manual unassisted THA.

Routine use of antibiotic-laden bone cement in total knee arthroplasty is a cost-effective practice in the single-payer healthcare system

PURPOSE

The purpose of this study was to determine the cost-effectiveness of antibiotic-laden bone cement (ALBC) in primary total knee arthroplasty (TKA) from the perspective of a single-payer healthcare system.

METHODS

A cost-utility analysis (CUA) was performed over a 2-year time horizon comparing primary TKA with either ALBC or regular bone cement (RBC) from the perspective of the single-payer Canadian healthcare system. All costs were in 2020 Canadian dollars. Health utilities were in the form of quality-adjusted life years (QALYs). Model inputs for cost, utilities and probabilities were derived from the literature as well as regional and national databases. One-way deterministic sensitivity analysis was performed.

RESULTS

Primary TKA with ALBC was found to be more cost-effective compared to primary TKA with RBC with an incremental cost-effectiveness ratio (ICER) of -3,637.79 CAD/QALY. The use of routine ALBC remained cost-effective even with cost increases of up to 50% per bag of ALBC. TKA with ALBC was no longer cost-effective if the rate of PJI following this practice increased 52%, or the rate of PJI following the use of RBC decreased 27%.

CONCLUSIONS

The routine use of ALBC in TKA is a cost-effective practice in the single-payer Canadian healthcare system. This remains to be the case even with a 50% increase in the cost of ALBC. Policy makers and hospital administrators of single-payer healthcare systems can leverage this model to inform their local funding policies. Future prospective reviews and randomized controlled trials from the perspective of various healthcare models can further shed light on this issue.

LEVEL OF EVIDENCE

III.

Cost-effectiveness of patient specific vs conventional instrumentation for total knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Over the past years, patient specific instrumentation (PSI) for total knee arthroplasty (TKA) has been implemented and routinely used. No clear answer has been given on its associated cost and cost-effectiveness when compared to conventional instrumentation (CI) for TKA.

AIM

To compare the cost and cost-effectiveness of PSI TKA compared to CI TKA.

METHODS

A literature search was performed in healthcare, economical healthcare, and medical databases (MEDLINE, EMBASE, CINAHL, Web of Science, Cochrane Library, EconLit). It was conducted in April 2021 and again in January 2022. Relevant literature included randomised controlled trials, retrospective studies, prospective studies, observational studies, and case control studies. All studies were assessed on methodological quality. Relevant outcomes included incremental cost-effectiveness ratio, quality-adjusted life years, total costs, imaging costs, production costs, sterilization associated costs, surgery duration costs and readmission rate costs. All eligible studies were assessed for risk of bias. Meta-analysis was performed for outcomes with sufficient data.

RESULTS

Thirty-two studies were included into the systematic review. Two were included in the meta-analysis. 3994 PSI TKAs and 13267 CI TKAs were included in the sample size. The methodological quality of the included studies, based on Consensus on Health Economic Criteria-scores and risk of bias, ranged from average to good. PSI TKA costs less than CI TKA when considering mean operating room time and its associated costs and tray sterilization per patient case. PSI TKA costs more compared to CI TKA when considering imaging and production costs. Considering total costs per patient case, PSI TKA is more expensive in comparison to CI TKA. Meta-analysis comparing total costs for PSI TKA, and CI TKA showed a significant higher cost for PSI TKA.

CONCLUSION

Cost for PSI and CI TKA can differ when considering distinct aspects of their implementation. Total costs per patient case are increased for PSI TKA when compared to CI TKA.

3D Bioprinting of Hyaline Articular Cartilage: Biopolymers, Hydrogels, and Bioinks

The musculoskeletal system, consisting of bones and cartilage of various types, muscles, ligaments, and tendons, is the basis of the human body. However, many pathological conditions caused by aging, lifestyle, disease, or trauma can damage its elements and lead to severe disfunction and significant worsening in the quality of life. Due to its structure and function, articular (hyaline) cartilage is the most susceptible to damage. Articular cartilage is a non-vascular tissue with constrained self-regeneration capabilities. Additionally, treatment methods, which have proven efficacy in stopping its degradation and promoting regeneration, still do not exist. Conservative treatment and physical therapy only relieve the symptoms associated with cartilage destruction, and traditional surgical interventions to repair defects or endoprosthetics are not without serious drawbacks. Thus, articular cartilage damage remains an urgent and actual problem requiring the development of new treatment approaches. The emergence of biofabrication technologies, including three-dimensional (3D) bioprinting, at the end of the 20th century, allowed reconstructive interventions to get a second wind. Three-dimensional bioprinting creates volume constraints that mimic the structure and function of natural tissue due to the combinations of biomaterials, living cells, and signal molecules to create. In our case-hyaline cartilage. Several approaches to articular cartilage biofabrication have been developed to date, including the promising technology of 3D bioprinting. This review represents the main achievements of such research direction and describes the technological processes and the necessary biomaterials, cell cultures, and signal molecules. Special attention is given to the basic materials for 3D bioprinting-hydrogels and bioinks, as well as the biopolymers underlying the indicated products.

Digital Rehabilitation after Knee Arthroplasty: A Multi-Center Prospective Longitudinal Cohort Study

Rehabilitation for total knee replacement (TKA) often involves in-person therapy sessions, which can be time consuming and costly. Digital rehabilitation has the potential to address these limitations, but most of these systems offer standardized protocols without considering the patient's pain, participation, and speed of recovery. Furthermore, most digital systems lack human support in case of need. The aim of this study was to investigate the engagement, safety, and clinical effectiveness of a personalized and adaptative app-based human-supported digital monitoring and rehabilitation program. In this prospective multi-center longitudinal cohort study, 127 patients were included. Undesired events were managed through a smart alert system. Doctors were triggered when there was a suspicion of problems. The drop-out rate, complications and readmissions, PROMS, and satisfaction were collected through the app. There was only 2% readmission. Doctor actions through the platform potentially avoided 57 consultations (85% of alerts). The adherence to the program was 77%, and 89% of the patients would recommend the use of the program. Personalized human-backed-up digital solutions can help to improve the rehabilitation journey of patients after TKA, lower healthcare-related costs by lowering the complication and readmission rate, and improve patient reported outcomes.

A mapping review on preoperative prognostic factors and outcome measures of revision total knee arthroplasty

To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration. We performed a systematic literature search in MEDLINE, Embase, and Web of Science. The search string included multiple synonyms of the following keywords: "revision TKA", "outcome" and "prognostic factor". We searched for studies assessing the association between at least one prognostic factor and at least one outcome measure after rTKA surgery. Data on sample size, study design, prognostic factors, outcomes, and the direction of the association was extracted and included in an evidence map. After screening of 5,660 articles, we included 166 studies reporting prognostic factors for outcomes after rTKA, with a median sample size of 319 patients (30 to 303,867). Overall, 50% of the studies reported prospectively collected data, and 61% of the studies were performed in a single centre. In some studies, multiple associations were reported; 180 different prognostic factors were reported in these studies. The three most frequently studied prognostic factors were reason for revision (213 times), sex (125 times), and BMI (117 times). Studies focusing on functional scores and patient-reported outcome measures as prognostic factor for the outcome after surgery were limited (n = 42). The studies reported 154 different outcomes. The most commonly reported outcomes after rTKA were: re-revision (155 times), readmission (88 times), and reinfection (85 times). Only five studies included costs as outcome. Outcomes and prognostic factors that are routinely registered as part of clinical practice (e.g. BMI, sex, complications) or in (inter)national registries are studied frequently. Studies on prognostic factors, such as functional and sociodemographic status, and outcomes as healthcare costs, cognitive and mental function, and psychosocial impact are scarce, while they have been shown to be important for patients with osteoarthritis.

Optimising the current model of care for knee osteoarthritis with the implementation of guideline recommended non-surgical treatments: a model-based health economic evaluation

AIMS OF THE STUDY

Structured exercise, education, weight management and painkiller prescription are guideline recommended non-surgical treatments for patients suffering from knee osteoarthritis. Despite its endorsement, uptake of guideline recommended non-surgical treatments remains low. It is unknown whether the implementation of these treatments into the current model of care for knee osteoarthritis would be cost-effective from a Swiss statutory healthcare perspective. We therefore aimed to (1) assess the incremental cost-effectiveness ratio of an optimised model of care incorporating guideline recommended non-surgical treatments in adults with knee osteoarthritis and (2) the effect of total knee replacement (TKR) delay with guideline recommended non-surgical treatments on the cost-effectiveness of the overall model of care.

METHODS

A Markov model from the Swiss statutory healthcare perspective was used to compare an optimised model of care incorporating guideline recommended non-surgical treatments versus the current model of care without standardised guideline recommended non-surgical treatments. Costs were derived from two Swiss health insurers, a national database, and a reimbursement catalogue. Utility values and transition probabilities were extracted from clinical trials and national population data. The main outcome was the incremental cost-effectiveness ratio for three scenarios: "base case" (current model of care vs optimised model of care with no delay of total knee replacement), "two-year delay" (current model of care vs optimised model of care + two-year delay of total knee replacement) and "five-year delay" (current model of care vs optimised model of care + five-year delay of total knee replacement). Costs and utilities were discounted at 3% per year and a time horizon of 70 years was chosen. Probabilistic sensitivity analyses were conducted.

RESULTS

The "base case" scenario led to 0.155 additional quality-adjusted life years (QALYs) per person at an additional cost per person of CHF 341 (ICER = CHF 2,203 / QALY gained). The "two-year delay" scenario led to 0.134 additional QALYs and CHF -14 cost per person. The "five-year delay" scenario led to 0.118 additional QALYs and CHF -501 cost per person. Delay of total knee replacement by two and five years led to an 18% and 36% reduction of revision surgeries, respectively, and had a cost-saving effect.

CONCLUSION

According to this Markov model, the optimisation of the current model of care by implementing guideline recommended non-surgical treatments would likely be cost-effective from a statutory healthcare perspective. If implementing guideline recommended non-surgical treatments delays total knee replacement by two or five years, the amount of revision surgeries may be reduced.

Sequentially Irradiated and Annealed Highly Cross-Linked Polyethylene: Clinical and Radiographic Outcomes in Total Knee Arthroplasty at 10-Year Follow-up

Highly cross-linked polyethylene (HXLPE) has become the preferred bearing surface in total hip arthroplasty. However, its acceptance in total knee arthroplasty (TKA) has not been as robust because of concerns pertaining to wear and its impact on implant failure. Therefore, this multicenter study was purposed to evaluate the 10-year (1) radiographic outcomes; (2) complications; and (3) implant survivorship in patients with TKA receiving a sequentially irradiated and annealed HXLPE. A retrospective, multi-center study was performed on 139 patients (171 TKAs) who underwent primary TKA with HXLPE and possessed a minimum of 10-year follow-up. Radiographs were analyzed for radiolucencies along the implant-fixation interface using the Modern Knee Society Radiographic Evaluation System. Kaplan-Meier analysis determined implant survivorship when the end points were revision for polyethylene wear and polyethylene revision for any reason. Sixteen TKAs (9.9%) demonstrated periprosthetic linear radio-lucencies. Seventeen TKAs (9.9%) required additional surgeries, 9 (5.3%) of which were revisions, with 1 (0.6%) TKA requiring revision because of polyethylene wear. Other causes of revision included instability (1.8%), infection (1.6%), and arthrofibrosis (1.6%). The mean time to revision was 5.9 years (range, 0.1-11.1 years). Survivorship pertaining to polyethylene revision for wear was 99.4%, whereas all-cause polyethylene revision was 94.7%. This study in patients undergoing primary TKA using a second-generation HXLPE demonstrated excellent results with respect to polyethylene wear characteristics and strength with a 99.4% survivorship at 10 years. [Orthopedics. 2023;46(2):e111-e117.].

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.

Open Reduction Internal Fixation Versus Distal Femoral Replacement (DFR) for Treatment of OTA/AO 33C Fractures in the Elderly: A Review of Functional Outcomes and Cost Analysis

OBJECTIVES

To determine the economic cost associated with the treatment of OTA/AO 33C fractures in patients older than 65 years of age using open reduction internal fixation (ORIF) or DFR and to assess the perioperative outcomes of elderly patients treated surgically following OTA/AO 33C fractures.

DESIGN

Retrospective cohort over a 10-year period.

SETTING

A single level-1 trauma center.

PARTICIPANTS AND INTERVENTION

Thirty-nine patients 65 or older with OTA/AO 33C fractures who underwent treatment with ORIF (n = 27) or DFR (n = 12) were included.

MAIN OUTCOME MEASUREMENTS

Direct cost associated with surgical treatment along with LOS, functional outcomes, patient-reported outcomes, and all-cause reoperation.

RESULTS

Index procedure costs were as follows: DFR: $ 61,259 vs. ORIF: $44,490 (P = 0.056). Five (20%) ORIF patients required revision versus one (8%) in the DFR group. Total cost when including reoperation resulted in DFR being $14,805 more costly, which was not significant. Hospital LOS was similar between groups; however, convalescent LOS was longer in ORIF patients (43.2 vs. 23.1 days, P = 0.02).

CONCLUSION

This study demonstrates that there is no significant difference in overall cost between ORIF and DFR when all costs are considered. A larger portion of DFR patients were able to mobilize postoperatively, with subacute length of stay being longer in ORIF patients. A multicenter trial is warranted to determine optimal treatment for this complex problem.

LEVEL OF EVIDENCE

Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Prognosis of the contralateral hip after primary total hip replacement: Can it be predicted?

INTRODUCTION

Coxarthrosis is one of the most frequent and disabling pathologies. 20% of individuals over 60 years of age will develop symptomatic coxarthrosis and 10% of them will need a hip replacement; it is probably one of the orthopaedic procedures that most increases quality of life. When we recommend arthroplasty in clinical practice, patients often ask about the prognosis of their other hip. Will it deteriorate in the same way? Will it be necessary to replace it? When? The aim of the study is to determine if there is any variable or radiological sign that predicts the medium-term prognosis of the contralateral hip after total hip arthroplasty.

MATERIAL AND METHODS

A retrospective review of patients who underwent total hip arthroplasty in our hospital during 2011 and 2012 was carried out, with a total of 543 patients. The coxarthrosis degree at X-ray was determined at the time of the first arthroplasty and at regular intervals during follow-up, according to the JOA and Tönnis classifications, analyzing each of the items included in these classifications. Its relation with the progression of osteoarthritis and the need of contralateral hip replacement was established.

RESULTS AND CONCLUSIONS

A progression of osteoarthritis of the contralateral hip could be expected in the next 3 years in 10% of patients. This progression will be greater and faster in those with JOA grade III-IV/Tönnis grade II-III, especially, in those with greater joint narrowing and femoral head shape score, and can reach between 25 and 30% of patients. The initial JOA/Tönnis degree is a predictive factor for requiring a hip replacement on the contralateral side.

[Translated article] Prognosis of the contralateral hip after primary total hip replacement: Can it be predicted?

INTRODUCTION

Coxarthrosis is one of the most frequent and disabling pathologies. 20% of individuals over 60 years of age will develop symptomatic coxarthrosis and 10% of them will need a hip replacement; it is probably one of the orthopaedic procedures that most increases quality of life. When we recommend arthroplasty in clinical practice, patients often ask about the prognosis of their other hip. Will it deteriorate in the same way? Will it be necessary to replace it? When? The aim of the study is to determine if there is any variable or radiological sign that predicts the medium-term prognosis of the contralateral hip after total hip arthroplasty.

MATERIAL AND METHODS

A retrospective review of patients who underwent total hip arthroplasty in our hospital during 2011 and 2012 was carried out, with a total of 543 patients. The coxarthrosis degree at X-ray was determined at the time of the first arthroplasty and at regular intervals during follow-up, according to the JOA and Tönnis classifications, analyzing each of the items included in these classifications. Its relation with the progression of osteoarthritis and the need of contralateral hip replacement was established.

RESULTS AND CONCLUSIONS

A progression of osteoarthritis of the contralateral hip could be expected in the next 3 years in 10% of patients. This progression will be greater and faster in those with JOA grade III-IV/Tönnis grade II-III, especially, in those with greater joint narrowing and femoral head shape score, and can reach between 25 and 30% of patients. The initial JOA/Tönnis degree is a predictive factor for requiring a hip replacement on the contralateral side.

Can Technology Assistance be Cost Effective in TKA? A Simulation-Based Analysis of a Risk-prioritized, Practice-specific Framework

BACKGROUND

Robotic, navigated, and patient-specific instrumentation (PSI) TKA procedures have been introduced to improve component placement precision and improve implant survivorship and other clinical outcomes. However, the best available evidence has shown that these technologies are ineffective in reducing revision rates in the general TKA patient population. Nonetheless, it seems plausible that these technologies could be an effective and cost-effective means of reducing revision risk in clinical populations that are at an elevated risk of revision because of patient-specific demographics (such as older age at index surgery, elevated BMI, and being a man). Since clinical trials on this topic would need to be very large, a simulation approach could provide insight on which clinical populations would be the most promising for analysis.

QUESTIONS/PURPOSES

We conducted a simulation-based analysis and asked: (1) Given key demographic parameters characterizing a patient population, together with estimates of the precision achievable with selected forms of technology assistance in TKA, can we estimate the expected distributions of anticipated reductions in lifetime revision risk for that population and the associated improvements in quality-adjusted life years (QALYs) that would be expected to result? (2) Are there realistic practice characteristics (such as combinations of local patient demographics and capital and per-procedure costs) for which applying a per-patient risk-prioritized policy for using technology-assisted TKA could be considered cost-effective based on projected cost savings from reductions in revision rates?

METHODS

We designed simulations of hypothetical practice-specific clinical scenarios, each characterized by patient volume, patient demographics, and technology-assisted surgical technique, using demographic information drawn from other studies to characterize two contrasting simulated clinical scenarios in which the distributions of factors describing patients undergoing TKA place one population at a comparatively elevated risk of revision (elevated-risk population) and the second at a comparatively reduced risk of revision (lower-risk population). We used results from previous systematic reviews and meta-analyses to estimate the implant precision in coronal plane alignment for patient-specific instrumentation, navigated, and robotic technology. We generated simulated TKA patient populations based on risk estimates from large clinical studies, structured reviews, and meta-analyses and calculated the patient-specific reduction in the revision risk and the change in QALYs attributable to the technology-assisted intervention in each of the two simulated clinical scenarios. We also incorporated a sensitivity analysis, incorporating variations in the effect size of deviations from overall coronal alignment on revision risk and difference in health state utilities acquired through a structured review process. We then simulated the outcomes of 25,000 operations per patient using the precisions associated with the conventional TKA technique, the three technology-assisted techniques, and a hypothetical technology-assisted intervention that could consistently deliver perfectly neutral overall coronal alignment, which is unachievable in practice. A risk-prioritized treatment policy was emulated by ordering the simulated patients from the highest to lowest predicted increase in QALYs, such that simulated patients who would see the greatest increase in the QALYs (and therefore the greatest reduction in lifetime revision risk) were the patients to receive technology-assisted TKA intervention in a practice. We used cost estimates acquired through a structured review process and calculated the net added costs of each of the three technology-assisted techniques as a function of the percent utilization (proportion of patients treated with technology assistance in a practice), factoring in fixed costs, per-procedure variable costs, and savings occurring from the prevention of future revision surgery. Finally, we calculated the incremental cost-effectiveness ratio (ICER) and marginal cost-effectiveness ratio (MCER) for each technology-assisted technique for the two clinical scenarios. We then used a Monte Carlo approach to simulate variations in key patient risk, health state, and economic factors as well as to obtain a distribution of estimates for cost-effectiveness. We considered an intervention to be cost effective if either the ICER or MCER values were below USD/QALY 63,000.

RESULTS

For the lower-risk population, the median reduction in the revision risk was 0.9% (0.4% to 2.2%, extrema from the sensitivity analysis) and 1.8% (0.9% to 4.4%) for PSI and robotic TKA, respectively, and 1.9% (1.0% to 4.6%) for ideal TKA. In contrast, the median reduction in the revision risk in the elevated-risk clinical scenario was 2.0% (1.2% to 3.4%) and 4.6% (2.7% to 8.5%) for PSI and robotic TKA and 5.1% (3.0% to 9.4%) for ideal TKA. Estimated differences in the cumulative gain in QALYs attributable to technology-assisted TKA ranged from 0.6 (0.2 to 1.8) to 4.0 (1.8 to 10.0) QALYs per 100 patients, depending on the intervention type and clinical scenario. For PSI, we found treating 15% of patients in the lower-risk population and 77% in the elevated-risk population could meet the threshold for being considered cost effective. For navigated TKA systems offering high alignment precision, we found the intervention could meet this threshold for practice sizes of at least 300 patients per year and a percent utilization of 27% in the lower-risk population. In the elevated-risk population, cost-effectiveness could be achieved in practice volumes as small as 100 patients per year with a percent utilization of at least 6%, and cost savings could be achieved with a percent utilization of at least 45%. We found that robotic TKA could only meet the threshold for being considered cost-effectiveness in the lower-risk population if yearly patient volumes exceeded 600 and for a limited range of percent utilization (27% to 32%). However, in the elevated-risk patient population, robotic TKA with high alignment precision could potentially be cost effective for practice sizes as small as 100 patients per year and a percent utilization of at least 20% if a risk-prioritized treatment protocol were used.

CONCLUSION

Based on these simulations, a selective-use policy for technology-assisted TKA that prioritizes using technology assistance for those patients at a higher risk of revision based on patient-specific factors could potentially meet the cost-effectiveness threshold in selected circumstances (for example, primarily in elevated-risk populations and larger practice sizes). Whether it does meet that threshold would depend significantly on the surgical precision that can be achieved in practice for a given proposed technology as well as on the true local costs of using the proposed technology. We further recommend that any future randomized trials seeking to demonstrate possible effects of technology assistance on revision risk focus on clinical populations that are at higher risk of revision (such as, patient populations that are relatively younger, have higher BMIs, and higher proportions of men).

CLINICAL RELEVANCE

This study suggests that technology assistance is only likely to prove cost effective in selected circumstances rather than in all clinical populations and practice settings. In general, we project that surgical navigation is most likely to prove cost effective in the widest range of circumstances, that PSI may be cost effective or cost neutral in a moderate range of circumstances, and that robotic surgery is only likely to be cost effective in moderately large practices containing patients who are on average at an intrinsically elevated risk of revision.

Staged Versus Simultaneous Bilateral Knee Arthroplasty: Does Minimal Cost Difference Justify Risks?

BACKGROUND

Simultaneous bilateral total knee arthroplasty (BTKA) is associated with a higher risk but can be perceived to afford faster improvement and mitigated costs versus staged BTKA. We aimed to explore (1) health care utilization, (2) surgical supply costs of simultaneous BTKA; and (3) 1-year improvement in patient-reported pain, function, and quality of life (QOL) versus staged BTKA.

METHODS

A prospective cohort of 198 simultaneous and 625 staged BTKAs was obtained (2016-2020). Simultaneous BTKA cohort was propensity score-matched (1:2) to a similar group of staged patients (simultaneous = 198 versus staged = 396). Outcomes included length of stay, discharge disposition, 90-day readmission, 1-year reoperation, surgical episode supply cost, Knee Injury and Osteoarthritis Outcome Score (KOOS)-pain, KOOS-Physical Function Short Form, and KOOS-QOL. Rates of attaining minimal clinically important difference and Patient Acceptable Symptomatic State were calculated.

RESULTS

Compared to both staged BTKA surgeries combined, simultaneous BTKA demonstrated shorter median net length of stay (2.00 [2.00, 3.00] days versus 2.00 [2.00, 4.00] days; P < .001) but higher rates of nonhome discharge (n = 56 [28.3%] versus n = 32 [4.04%]; P < .001), 90-day readmission (n = 20 [10.1%] versus n = 48 [6.06%]; P = .047) and similar reoperation rates (P = .44). Simultaneous BTKA afforded slight reduction in net surgical cost compared to that of both staged BTKAs combined ($643; P = .028). There was no significant difference in 1-year improvement and minimal clinically important difference attainment rates with simultaneous versus staged BTKA for KOOS-pain (P = .137 and P = .99), KOOS-QOL (P = .095 and P = .81), or KOOS-Physical Function Short Form (P = .75 and P = .49, respectively) or Patient Acceptable Symptomatic State (P = .12).

CONCLUSION

Staged BTKA is associated with similar 1-year pain, function, and QOL at a better safety profile and minimal surgical supply cost increase compared to simultaneous BTKA.

No Difference in Quality-Of-Life Outcomes in the First 7 Years Following Primary Total Knee Arthroplasty Performed Using Computer Navigation Versus Conventional Referencing: A Propensity Score-Matched Analysis

BACKGROUND

Computer navigation techniques can potentially improve both the accuracy and precision of prosthesis implantation in total knee arthroplasty (TKA) but its impact on quality-of-life outcomes following surgery remains unestablished.

METHODS

An institutional arthroplasty registry was queried to identify patients with TKA performed between January 1, 2007 and December 31, 2019. Propensity score matching based on demographical, medical, and surgical variables was used to match computer-navigated to conventionally referenced cases. The primary outcomes were Veterans RAND 12 Item Health Survey scores (VR-12 PCS and MCS), Short Form 6 Dimension utility values (SF-6D), and quality-adjusted life years (QALYs) in the first 7 years following surgery.

RESULTS

A total of 629 computer-navigated TKAs were successfully matched to 1,351 conventional TKAs. The VR-12 PCS improved by a mean of 12.75 and 11.94 points in computer-navigated and conventional cases at 12-month follow-up (P = .25) and the VR-12 MCS by 6.91 and 5.93 points (P = .25), respectively. The mean VR-12 PCS improvement at 7-year follow-up (34.4% of the original matched cohort) for navigated and conventional cases was 13.00 and 12.92 points (P = .96) and for the VR-12 MCS was 4.83 and 6.30 points (P = .47), respectively. The mean improvement in the SF-6D utility score was 0.164 and 0.149 points at 12 months (P = .11) and at 7 years was 0.115 and 0.123 points (P = .69), respectively. Computer-navigated cases accumulated 0.809 QALYs in the first 7 years, compared to 0.875 QALYs in conventionally referenced cases (P = .65). There were no differences in these outcomes among a subgroup analysis of obese patients (body mass index ≥ 30 kg/m²).

CONCLUSION

The use of computer navigation did not provide an incremental benefit to quality-of-life outcomes at a mean of 2.9 years following primary TKA performed for osteoarthritis when compared to conventional referencing techniques.

Estimating incidence rates of periprosthetic joint infection after hip and knee arthroplasty for osteoarthritis using linked registry and administrative health data

AIMS

The aim of this study was to estimate the 90-day periprosthetic joint infection (PJI) rates following total knee arthroplasty (TKA) and total hip arthroplasty (THA) for osteoarthritis (OA).

METHODS

This was a data linkage study using the New South Wales (NSW) Admitted Patient Data Collection (APDC) and the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), which collect data from all public and private hospitals in NSW, Australia. Patients who underwent a TKA or THA for OA between 1 January 2002 and 31 December 2017 were included. The main outcome measures were 90-day incidence rates of hospital readmission for: revision arthroplasty for PJI as recorded in the AOANJRR; conservative definition of PJI, defined by T84.5, the PJI diagnosis code in the APDC; and extended definition of PJI, defined by the presence of either T84.5, or combinations of diagnosis and procedure code groups derived from recursive binary partitioning in the APDC.

RESULTS

The mean 90-day revision rate for infection was 0.1% (0.1% to 0.2%) for TKA and 0.3% (0.1% to 0.5%) for THA. The mean 90-day PJI rates defined by T84.5 were 1.3% (1.1% to 1.7%) for TKA and 1.1% (0.8% to 1.3%) for THA. The mean 90-day PJI rates using the extended definition were 1.9% (1.5% to 2.2%) and 1.5% (1.3% to 1.7%) following TKA and THA, respectively.

CONCLUSION

When reporting the revision arthroplasty for infection, the AOANJRR substantially underestimates the rate of PJI at 90 days. Using combinations of infection codes and PJI-related surgical procedure codes in linked hospital administrative databases could be an alternative way to monitor PJI rates.Cite this article: Bone Joint J 2022;104-B(9):1060-1066.

Outcome measures in total hip arthroplasty: have our metrics changed over 15 years?

INTRODUCTION

Consensus has not been reached regarding ideal outcome measures for total hip arthroplasty (THA) clinical evaluation and research. The goal of this review was to analyze the trends in outcome metrics within the THA literature and to discuss the potential impact of instrument heterogeneity on clinical practice.

MATERIALS AND METHODS

A PubMed search of all manuscripts related to THA from January 2005 to December 2019 was performed. Statistical and linear regression analyses were performed for individual outcome metrics as a proportion of total THA publications over time.

RESULTS

There was a statistically significant increase in studies utilizing outcomes metrics between 2005 and 2019 (15.1-29.5%; P < 0.001; R² = 98.1%). Within the joint-specific subcategory, use of the Harris Hip Score (HHS) significantly decreased from 2005 to 2019 (82.8-57.3%; P < 0.001), use of the Hip Disability and Osteoarthritis Outcome Score (HOOS) significantly increased (0-6.7%; P < 0.001), and the modified HHS significantly increased (0-10.5%; P < 0.001). In the quality of life subcategory, EQ-5D demonstrated a significant increase in usage (0-34.8%; P < 0.001), while Short Form-36 significantly decreased (100% vs. 27.3%; P = 0.008).

CONCLUSIONS

The utilization of outcome-reporting metrics in THA has continued to increase, resulting in added complexity within the literature. The utilization rates of individual instruments have shifted over the past 15 years. Additional study is required to determine which specific instruments are recommended.

Should an Age Cutoff Be Considered for Elective Total Knee Arthroplasty Patients? An Analysis of Operative Success Based on Patient-Reported Outcomes

Total knee arthroplasty (TKA) is increasing in the elderly population; however, some patients, family members, and surgeons raise age-related concerns over expected improvement and risks. This study aimed to (1) evaluate the relationship between age and change in patient-reported outcome measures (PROMs); (2) model how many patients would be denied improvements in PROMs if hypothetical age cutoffs were implemented; and (3) assess length of stay (LOS), readmission, reoperation, and mortality per age group. A prospective cohort of 4,396 primary TKAs (August 2015-August 2018) was analyzed. One-year PROMs were evaluated via Knee injury and Osteoarthritis Outcome Score (KOOS)-pain, -physical function short form (-PS), and -quality of life (-QOL), as well as Veterans Rand-12 (VR-12) physical (-PCS) and mental component (-MCS) scores. Positive predictive values (PPVs) of the number of postoperative "failures" (i.e., unattained minimal clinically important difference in PROMs) relative to number of hypothetically denied "successes" from a theoretical age-group restriction was estimated. KOOS-PS and QOL median score improvements were equivalent among all age groups (p = 0.946 and p = 0.467, respectively). KOOS-pain improvement was equivalent for ≥80 and 60-69-year groups (44.4 [27.8-55.6]). Median VR-12 PCS improvements diminished as age increased (15.9, 14.8, and 13.4 for the 60-69, 70-79, and ≥80 groups, respectively; p = 0.002) while improvement in VR-12 MCS was similar among age groups (p = 0.440). PPV for failure was highest in the ≥80 group, yet remained <34% for all KOOS measures. Overall mortality was highest in the ≥80 group (2.14%, n = 9). LOS >2, non-home discharge, and 90-day readmission were highest in the ≥80 group (8.11% [n = 24], p < 0.001; 33.7% [n = 109], p < 0.001; and 34.4% [n = 111], p = 0.001, respectively). Elderly patients exhibited similar improvement in PROMs to younger counterparts despite higher LOS, non-home discharge, and 90-day readmission. Therefore, special care pathways should be implemented for those age groups.

Combinations of Preoperative Patient-Reported Outcome Measure Phenotype (Pain, Function, and Mental Health) Predict Outcome After Total Knee Arthroplasty

BACKGROUND

Value-driven healthcare models prioritize patient-perceived benefits to quantify the quality of care through patient-reported outcome measures (PROMs). The Patient Acceptable Symptom State (PASS) is the highest level of symptom beyond which a patient considers his/her condition satisfactory. We identified preoperative phenotypes of PROMs associated with not achieving PASS at 1 year following total knee arthroplasty (TKA) and explored the relationships between such phenotypes with hospital utilization parameters.

METHODS

A prospective institutional cohort of 5,274 primary TKAs for osteoarthritis from 2016 to 2019 with 1-year follow-up were included. Preoperative scores on Knee Disability and Osteoarthritis Outcome Score (KOOS) Pain, KOOS-Physical function Short form (PS), and Veterans RAND 12-Item Health Survey (VR-12) Mental Component Summary (MCS) were used to develop patient phenotypes. Associations between preoperative "phenotype" and 1-year PASS, discharge disposition, length of stay, 90-day readmission, and 1-year reoperation were evaluated using multivariate regression.

RESULTS

In total, 16.3% (n = 862) of patients reported their state as "not acceptable" at 1 year. A combination of low scores in each of the presently examined PROMs was associated with the highest odds of 1-year dissatisfaction (odds ratio 2.18, 95% confidence interval 1.74-2.74). The PROM phenotypes were the greatest drivers compared to sociodemographic variables in predicting satisfaction. Combinations of low scores in VR-12 MCS and KOOS-PS were significantly associated with both non-home discharge status and prolonged length of stay.

CONCLUSION

Patients with combined lower preoperative scores across multiple PROMs (KOOS-Pain <41.7, KOOS-PS <51.5, and VR-12 MCS <52.8) have increased odds of dissatisfaction after TKA. Measuring pain, function, and mental health concurrently as phenotypes may help identify TKA patients at risk for not achieving a satisfactory outcome at 1 year.

Cost-effectiveness of Same-day Discharge Surgery for Primary Total Hip Arthroplasty: A Pragmatic Randomized Controlled Study

Background

Total hip arthroplasty (THA) causes a great medical burden globally, and the same-day discharge (SDD) method has previously been considered to be cost saving. However, a standard cost-effectiveness analysis (CEA) in a randomized controlled trial (RCT) is needed to evaluated the benefits of SDD when performing THA from the perspective of both economic and clinical outcomes.

Methods

Eighty-four participants undergoing primary THA were randomized to either the SDD group or the inpatient group. Outcomes were assessed by an independent orthopedist who was not in the surgical team, using the Oxford Hip Score (OHS), EuroQol 5D (EQ-5D), SF-36 scores and the quality-adjusted life years (QALYs). All the cost information was also collected.

Results

The mean stay of patients in the SDD group was 21.70 ± 3.45 h, while the inpatient group was 78.15 ± 26.36 h. This trial did not detect any significant differences in OHS and QALYs. The total cost in the SDD group was significantly lower than that in the inpatient group (¥69,771.27 ± 6,608.00 vs. ¥80,666.17 ± 8,421.96, p < 0.001). From the perspective of total cost, when measuring OHS, the incremental effect was -0.12 and the incremental cost was -¥10,894.90. The mean incremental cost-effectiveness ratio (ICER) was 90,790.83. When measuring QALYs, the incremental effect was 0.02, and the ICER was negative. Sensitivity analysis produced similar results.

Conclusions

SDD has an acceptable likelihood of being more cost-effective than the traditional inpatient option. After conducting cost-utility analysis, SDD resulted in better QALYs, while significantly reducing the total cost.

What Are Drivers of Readmission for Readmission-Requiring Venous Thromboembolic Events After Primary Total Hip Arthroplasty? An Analysis of 544,443 Cases

BACKGROUND

Venous thromboembolism (VTE) is a potential postoperative complication after total hip arthroplasty (THA). These events present with a range of severity, and some require readmission. The present study aimed to identify unexplored risk factors for severe VTE that lead to hospital readmission.

METHODS

The Agency of Healthcare Research and Quality's National Readmissions Database was retrospectively queried for all patients who underwent primary THA (January 2016 to December 2018). Study population included patients who were readmitted for VTE within 90 days after an elective THA. Bivariate and multivariate regression analyses were performed using patient demographics, insurance status, elective nature of the surgery, healthcare institution characteristics, and baseline comorbidities.

RESULTS

Higher risk of readmission for VTE was evident among elderly (71-80 years vs <40 years: odds ratio [OR] 1.7, 95% confidence interval [CI] 1.3-2.2, P = .0002), male patients (OR 1.2, 95% CI 1.2-1.3). Nonelective THAs were associated with markedly higher odds of readmission for VTE (OR 20.5, 95% CI 18.9-22.2), peripheral vascular disease (OR 1.2, 95% CI 1.1-1.4), lymphoma (OR 1.5, 95% CI 1.1-2.1), metastatic cancer (OR 1.8, 95% CI 1.4-2.2), obesity (OR 1.5, 95% CI 1.4-1.6), and fluid-electrolyte imbalance (OR 1.1, 95% CI 1.0-1.2). Home health care (OR 0.8, 95% CI 0.7-0.8) and discharge to skilled nursing facility (OR 0.7, 95% CI 0.7-0.8) had lower odds of readmission for VTE vs unsupervised home discharge, while insurance type was not a significant driver(P > .05).

CONCLUSION

One in 135 THA patients is likely to experience a VTE requiring readmission after THA. Male patients, age >70 years, and specific baseline comorbidities increase such risk. Furthermore, discharge to a supervised setting mitigated the risk of VTE requiring readmission compared to unsupervised discharge. As VTE prophylaxis protocols continue to evolve, these patients may require optimized perioperative care pathways to mitigate VTE complications.

Development of a decision analytical framework to prioritise operating room capacity: lessons learnt from an empirical example on delayed elective surgeries during the COVID-19 pandemic in a hospital in the Netherlands

OBJECTIVE

To develop a prioritisation framework to support priority setting for elective surgeries after COVID-19 based on the impact on patient well-being and cost.

DESIGN

We developed decision analytical models to estimate the consequences of delayed elective surgical procedures (eg, total hip replacement, bariatric surgery or septoplasty).

SETTING

The framework was applied to a large hospital in the Netherlands.

OUTCOME MEASURES

Quality measures impacts on quality of life and costs were taken into account and combined to calculate net monetary losses per week delay, which quantifies the total loss for society expressed in monetary terms. Net monetary losses were weighted by operating times.

RESULTS

We studied 13 common elective procedures from four specialties. Highest loss in quality of life due to delayed surgery was found for total hip replacement (utility loss of 0.27, ie, 99 days lost in perfect health); the lowest for arthroscopic partial meniscectomy (utility loss of 0.05, ie, 18 days lost in perfect health). Costs of surgical delay per patient were highest for bariatric surgery (€31/pp per week) and lowest for arthroscopic partial meniscectomy (-€2/pp per week). Weighted by operating room (OR) time bariatric surgery provides most value (€1.19/pp per OR minute) and arthroscopic partial meniscectomy provides the least value (€0.34/pp per OR minute). In a large hospital the net monetary loss due to prolonged waiting times was €700 840 after the first COVID-19 wave, an increase of 506% compared with the year before.

CONCLUSIONS

This surgical prioritisation framework can be tailored to specific centres and countries to support priority setting for delayed elective operations during and after the COVID-19 pandemic, both in and between surgical disciplines. In the long-term, the framework can contribute to the efficient distribution of OR time and will therefore add to the discussion on appropriate use of healthcare budgets. The online framework can be accessed via: https://stanwijn.shinyapps.io/priORitize/.

Durable Improvement in Generic and Fibroid-Specific Quality of Life in Women Treated with Transcervical Fibroid Ablation with the Sonata System After Three Years

Objective:

To determine quality-adjusted life years (QALYs) over 3 years after transcervical fibroid ablation (TFA) with the Sonata System.

Methods:

The SONATA trial was a prospective multicenter interventional trial that assessed the safety and efficacy of TFA for treatment of women with symptomatic uterine fibroids. Change in generic health status was assessed with the EuroQol 5-Dimension questionnaire (0–1 scale). Fibroid-specific quality of life (QOL) was measured on a 0 to 100 scale with the health-related quality of life subscale of the Uterine Fibroid Symptom and Quality-of-Life (UFS-QOL). The number of QALYs gained relative to baseline and cumulative QALYs were calculated using the area under the curve at each follow-up visit over 3 years.

Results:

Among 147 women receiving TFA, fibroid-specific QOL increased from 40 ± 21 at baseline to 84 ± 19 at 1 year and 83 ± 23 at 3 years (p < 0.001). Generic QOL increased from 0.72 ± 0.21 at baseline to 0.89 ± 0.12 at 1 year and 0.88 ± 0.16 at 3 years (p < 0.001). Over 3 years, TFA resulted in 1.24 ± 0.64 QALYs gained when using fibroid-specific health utility scores and 0.49 ± 0.61 QALYs gained when using generic health utility scores. Cumulative QALYs experienced at 3 years as a percentage of perfect health were 82% with fibroid-specific scores and 88% with generic health scores.

Conclusions:

Women treated by TFA with the Sonata System for symptomatic uterine fibroids reported durable improvements in generic and fibroid-specific QOL, as well as clinically meaningful increases in QALYs over 3 years. Clinical Trials.gov ID: NCT02228174. (J GYNECOL SURG 38:143)

Chronic Pseudoaneurysm and Anterior Dislocation After Total Hip Arthroplasty Complicated by Arterial Injury: A Case Report

CASE

A 64-year-old man presented 18 months after total hip arthroplasty complicated by vascular injury with a history of leg pain, inability to mobilize, and progressive chronic leg edema. It is presumed that there was persistent subtle bleeding over time with pseudoaneurysm formation and prosthetic hip dislocation secondary to the mass effect.

CONCLUSION

Physicians should consider pseudoaneurysm as a possible diagnosis when confronted with a large intra-articular mass in the hip after a relatively short follow-up period, particularly in the context of a prior vascular injury at the time of the index procedure.

Simultaneous bilateral total knee arthroplasty has higher in-hospital complications than both staged surgeries: a nationwide propensity score matched analysis of 38,764 cases

PURPOSE

To investigate (1) healthcare utilization, (2) in-hospital metrics and (3) total in-hospital costs associated with simultaneous versus staged BTKA while evaluating staged BTKA as a single process consisting of two combined episodes.

METHODS

The national readmissions database was reviewed for simultaneous and staged (two primary unilateral TKAs12 months apart) BTKA patients (2016-2017). A total of 19,382 simultaneous BTKAs were identified, and propensity score matched (1:1) to staged BTKA patients (19,382 patients; 38,764 surgeries) based on demographics, comorbidities, and socioeconomic determinants. Outcomes included healthcare utilization [length of stay (LOS) and discharge disposition], in-hospital periprosthetic fractures, non-mechanical complications, and costs. Staged BTKA was evaluated as one process consisting of two episodes. For each staged patient, continuous outcomes were evaluated via the sum of both episodes. Categorical outcomes were added, and percents were expressed relative to total number of surgeries (n = 38,764).

RESULTS

Simultaneous BTKA had longer LOS (5.0 days ± 4.7 vs. 4.5 days ± 3.5; p < 0.001), higher non-home discharge [36.9% (n = 7150/19,382) vs. 13.6% (n = 5451/38,764)], in-hospital periprosthetic fractures [0.13% (26/19,382) vs. 0.08% (31/38,764); p = 0.049], any non-mechanical complication [33.76% (6543/19,382) vs.15.93% (6177/38,764); p < 0.0001], hematoma/seroma formation [0.11% (22/19,382) vs. 0.05% (20/38,764); p = 0.0088], wound disruption [0.08% (16/19,382) vs. 0.04% (16/38,764); p = 0.0454], and any infection [1.13% (219/19,382) vs. 0.50% (194/38,764); p < 0.0001]. Average in-hospital costs for the two staged BTKA episodes combined were $5006 higher than those of simultaneous BTKA ($28,196 ± $18,488 vs. $33,202 ± $15,240; p < 0.001).

CONCLUSION

Simultaneous BTKA had higher healthcare utilization and in-hospital complications than both episodes of staged BTKA combined, with a minimal in-hospital cost savings. Future studies are warranted to further explore patient selection who would benefit from BTKA.

Outcomes of an Institutional Rapid Recovery Protocol for Total Joint Arthroplasty at a Safety Net Hospital

Rapid recovery protocols (RRPs) for total joint arthroplasty (TJA) can reduce hospital length of stay (LOS) and improve patient care in select cohorts; however, there is limited literature regarding their utility in marginalized patient populations. This report aimed to evaluate the outcomes of an institutional RRP for TJA at a safety net hospital.

Feasibility and Effect of a Wearable Motion Sensor Device in Facilitating In-Home Rehabilitation Program in Patients after Total Knee Arthroplasty: A Preliminary Study

Postoperative home-based rehabilitation programs are essential for facilitating functional recovery after total knee replacement (TKA). This study aimed to verify the feasibility of applying a wearable motion sensor device (MSD) to assist patients in performing home-based exercises after TKA. The interrater reliability of the measurement for knee mobility and the time spent completing the 5-times sit-to-stand test (5TSST) by two experienced physicians and using the MSD in 12 healthy participants was first assessed. A prospective control trial was then conducted, in which 12 patients following TKA were allocated to two groups: the home-based exercise group and the MSD-assisted rehabilitation group. Changes in knee range of motion, pain, functional score, performance, and exercise completion rates were compared between the groups over two months of follow-up. MSD-measured knee mobility and 5TSST exhibited excellent reliability compared with the physician measurements. Furthermore, patients in the MSD-assisted rehabilitation group reported higher training compliance than participants in the home-based exercise group, which led to better outcomes in the knee extension angle and maximal and average angular velocity in 5TSST. MSD-assisted home-based rehabilitation following TKA is a feasible treatment model for telerehabilitation because it enhances patients’ compliance to training, which improves functional recovery.

The SWING test: A more reliable test than passive clinical tests for assessing sagittal plane hip mobility

BACKGROUND

Clinical assessment of sagittal plane hip mobility is usually performed using the Modified Thomas Test (for extension) and the Straight-Leg-Raise (for flexion) with a goniometer. These tests have limited reliability, however. An active swinging leg movement test (the SWING test), assessed using 3D motion analysis, could provide an alternative to these passive clinical tests.

RESEARCH QUESTION

Is the SWING test a more reliable alternative to evaluate hip mobility, in comparison to the clinical extension and flexion tests?

METHODS

Ten asymptomatic adult participants were evaluated by two investigators over three sessions. Participants performed 10 maximal hip extensions and flexions, with both legs straight and no trunk movement (the SWING test). Hip kinematics was assessed using a 3D motion analysis system. Maximal and minimal hip angles were calculated for each swing and represented maximal hip flexion (SWING flexion) and extension (SWING extension), respectively. The Modified Thomas Test and Straight-Leg-Raise were repeated 3 times for each leg. On the first day, both investigators performed all the tests (SWING + Modified Thomas Test + Straight-Leg-Raise). A week later, a single investigator repeated all the tests. Inter-rater, intra-rater, within-day and between-day reliability were evaluated using intra-class correlation.

RESULTS

Intra-class correlation coefficients for all the tests were superior to 0.8, except for the Modified Thomas Test's intra-rater, between-day (intra-class correlation 0.673) and the Straight-Leg-Raise's inter-rater, within-day (intra-class correlation 0.294). The SWING test always showed a higher intra-class correlation coefficient than the passive clinical tests. The only significant correlation found was for the Straight-Leg-Raise and SWING flexion (r = 0.48; P < 0.001).

SIGNIFICANCE

The SWING test seems to be an alternative to existing passive clinical tests, offering better reliability for assessing sagittal plane hip mobility.

The subjective knee value is a valid single-item survey to assess knee function in common knee disorders

INTRODUCTION

The patient's perspective plays a key role in judging the effect of knee disorders on physical function. We have introduced the Subjective Knee Value (SKV) to simplify the evaluation of individual's knee function by providing one simple question. The purpose of this prospective study was to validate the SKV with accepted multiple-item knee surveys across patients with orthopaedic knee disorders.

MATERIALS AND METHODS

Between January through March 2020, consecutive patients (n = 160; mean age 51 ± 18 years, range from 18 to 85 years, 54% women) attending the outpatient clinic for knee complaints caused by osteoarthritis (n = 69), meniscal lesion (n = 45), tear of the anterior cruciate ligament (n = 23) and focal chondral defect (n = 23) were invited to complete a knee-specific survey including the SKV along with the Knee Injury Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee subjective knee form (IKDC-S). The Pearson correlation coefficient was used to evaluate external validity between the SKV and each patient-reported outcome measure (PROM) separately. Furthermore, patient's compliance was assessed by comparing responding rates.

RESULTS

Overall, the SKV highly correlated with both the KOOS (R = 0.758, p < 0.05) and the IKDC-S (R = 0.802, p < 0.05). This was also demonstrated across all investigated diagnosis- and demographic-specific (gender, age) subgroups (range 0.509-0.936). No relevant floor/ceiling effects were noticed. The responding rate for the SKV (96%) was significantly higher when compared with those for the KOOS (81%) and the IKDC-S (83%) (p < 0.05).

CONCLUSION

At baseline, the SKV exhibits acceptable validity across all investigated knee-specific PROMs in a broad patient population with a wide array of knee disorders. The simplified survey format without compromising the precision to evaluate individual's knee function justifies implementation in daily clinical practice.

LEVEL OF EVIDENCE

II, cohort study (diagnosis).

Implementation of an enhanced recovery protocol at a safety net hospital : a silver lining to COVID-19?

AIMS

This study aimed to evaluate whether an enhanced recovery protocol (ERP) for arthroplasty established during the COVID-19 pandemic at a safety net hospital can be associated with a decrease in hospital length of stay (LOS) and an increase in same-day discharges (SDDs) without increasing acute adverse events.

METHODS

A retrospective review of 124 consecutive primary arthroplasty procedures performed after resuming elective procedures on 11 May 2020 were compared to the previous 124 consecutive patients treated prior to 17 March 2020, at a single urban safety net hospital. Revision arthroplasty and patients with < 90-day follow-up were excluded. The primary outcome measures were hospital LOS and the number of SDDs. Secondary outcome measures included 90-day complications, 90-day readmissions, and 30day emergency department (ED) visits.

RESULTS

The mean LOS was significantly reduced from 2.02 days (SD 0.80) in the pre-COVID cohort to 1.03 days (SD 0.65) in the post-COVID cohort (p < 0.001). No patients in the pre-COVID group were discharged on the day of surgery compared to 60 patients (48.4%) in the post-COVID group (p < 0.001). There were no significant differences in 90-day complications (13.7% (n = 17) vs 9.7% (n = 12); p = 0.429), 30-day ED visits (1.6% (n = 2) vs 3.2% (n = 4); p = 0.683), or 90-day readmissions (2.4% (n = 3) vs 1.6% (n = 2); p = 1.000) between the pre-COVID and post-COVID groups, respectively.

CONCLUSION

Through use of an ERP, arthroplasty procedures were successfully resumed at a safety net hospital with a shorter LOS and increased SDDs without a difference in acute adverse events. The resulting increase in healthcare value therefore may be considered a 'silver lining' to the moratorium on elective arthroplasty during the COVID-19 pandemic. These improved efficiencies are expected to continue in post-pandemic era. Cite this article: Bone Jt Open 2021;2(10):871-878.

Non-Antimicrobial Adjuvant Strategies to Tackle Biofilm-Related Staphylococcus aureus Prosthetic Joint Infections

Staphylococcus aureus frequently causes community- and hospital-acquired infections. S. aureus attachment followed by biofilm formation on tissues and medical devices plays a significant role in the establishment of chronic infections. Staphylococcal biofilms encase bacteria in a matrix and protect the cells from antimicrobials and the immune system, resulting in infections that are highly resistant to treatment. The biology of biofilms is complex and varies between organisms. In this review, we focus our discussion on S. aureus biofilms and describe the stages of their formation. We particularly emphasize genetic and biochemical processes that may be vulnerable to novel treatment approaches. Against this background, we discuss treatment strategies that have been successful in animal models of S. aureus biofilm-related infection and consider their possible use for the prevention and eradication of biofilm-related S. aureus prosthetic joint infection.

Perioperative Immunonutrition in Elderly Patients Undergoing Total Hip and Knee Arthroplasty: Impact on Postoperative Outcomes

BACKGROUND

Arthroplasties in elderly patients are surgeries performed to ensure their quality of life. Perioperative care with specific nutrients can improve nutrition status and metabolic response to orthopedic surgeries, such as total knee arthroplasty (TKA) and total hip arthroplasty (THA).

METHODS

Retrospective study with elderly patients divided into 2 groups: control and immunonutrition. The immunonutrition group was instructed to start oral intake of the nutrition supplement 5 days before and to resume it 5 days after arthroplasty (200 mL, 3 times per day). The following were analyzed as primary and secondary outcomes: length of stay (LOS), infectious and noninfectious complications, need for intensive care unit (ICU), transfusion requirement, and C-reactive protein.

RESULTS

A total of 3015 elderly patients met the inclusion criteria: control group (n = 1398) and immunonutrition group (n = 1617). Overall, 81.2% were women and mean age was 72.6 ± 6.9 years. Immunonutrition group had a shorter LOS in hours (32.0 ± 19.4 vs 56.0 ± 26.4; P < .001) and lower rates of infectious complications (2.2% vs 4.6%; P < .001). Noninfectious complications and need for ICU also had lower rates in the immunonutrition group. In the logistic regression analysis, immunonutrition reduced the chance of infectious complications by 55% (odds ratio [OR], 0.45; 95% CI, 0.30-0.68; P < .001) even after adjusting for variables (OR, 0.45; 95% CI, 0.28-0.71; P < .001).

CONCLUSION

Perioperative immunonutrition in elderly patients undergoing THA or TKA may shorten postoperative LOS and reduce infectious and noninfectious complications and transfusion requirement.