General anesthesia is not associated with dementia in older adults with osteoarthritis for hip/knee replacements, a national population-based nested case-control study

BACKGROUND

Dementia is a prevalent neurological condition, yet the relationship between dementia and general anesthesia remains uncertain. The study aimed to explore the association between general anesthesia and dementia using a nationwide population-based database.

METHODS

The study extracted data from Taiwan's national health insurance, which encompassed the records of one million insured residents. A total of 59,817 patients aged 65 years and above, diagnosed with osteoarthritis between 2002 and 2010, were included. Among these patients, 3277 individuals with an initial diagnosis of dementia between 2004 and 2013 were matched with non-dementia patients based on age, gender, and the date of osteoarthritis diagnosis. Following a 1:2 random matching, the case group included 2171 patients with dementia, while the control group consisted of 4342 patients without dementia. The data was analyzed using conditional and unconditional logistic regressions.

RESULTS

No significant differences in the odds of dementia were found between individuals exposed to general and regional anesthesia during hip/knee replacement surgeries (OR = 1.11; 95%CI: 0.73-1.70), after adjusting for age, sex, and co-morbidities. Similarly, there were no significant differences in the odds of dementia based on different durations of anesthesia exposure (General: <2 h: OR = 0.91, 95%CI = 0.43-1.92; 2-4 h: OR = 1.21, 95%CI = 0.82-1.79; >4 h: OR = 0.39, 95%CI = 0.15-1.01; compared to no exposure. Regional: <2 h: OR = 1.18, 95%CI = 0.85-1.62; 2-4 h: OR = 0.9, 95%CI = 0.64-1.27; >4 h: OR = 0.55, 95%CI = 0.15-1.96; compared to no exposure). Likewise, no significant differences were observed in the odds of dementia based on the number of replacement surgeries (twice: OR = 0.74, 95%CI = 0.44-1.23, compared to once).

CONCLUSION

Neither general anesthesia nor regional anesthesia in hip/knee surgery was associated with dementia. Different numbers and durations of anesthesia exposure showed no significant differences in the odds for dementia.

Variation in Utilization of Postoperative Rehabilitation After Total Hip Arthroplasty in Japan

OBJECTIVE

The use of rehabilitation after arthroplasty in Japan is unknown. We aimed to identify utilization of postoperative rehabilitation after total hip arthroplasty (THA) and to explore the factors associated with rehabilitation usage.

DESIGN

A retrospective cohort study using the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB).

SETTING

Hospitals nationwide.

PARTICIPANTS

Patients aged >40 years who underwent primary THA between 2017 and 2018 (N=51,332).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The proportion of patients who underwent postoperative rehabilitation and the number of rehabilitation days were also calculated. Patient demographic characteristics, hospital case volumes, and regions associated with continuing postoperative rehabilitation were analyzed using a Cox proportional hazards model.

RESULTS

Eligible patients were selected from 3033 hospitals, of whom 41,192 (80%) were women. Of these, 94% used inpatient rehabilitation, and 20% received outpatient rehabilitation. The mean durations of rehabilitation were 47±72 days for inpatient and 195±109 days for outpatient, respectively. Large-scale hospitals performing more than 200 procedures annually had the shortest duration of inpatient rehabilitation (36-65 days) and the longest duration of outpatient rehabilitation (220-109 days) compared with smaller hospitals. The regression model consistently showed that rehabilitation continued longer at hospitals with over 200 patients per year (HR 0.96, 95% CI 0.93-0.99, P<.007).

CONCLUSION

The Japanese health care system provided higher access to inpatient rehabilitation after THA than other countries. One limitation of this study is that long-term care insurance data were not analyzed. However, outpatient rehabilitation vary according to hospital case volume. Further research is needed to determine the causes of variation in rehabilitation use and the effect of variation on patient outcomes.

Trends in Incidence of Hip Fracture and Hip Replacement in Denmark, 1996 to 2018

Importance

The past several decades have witnessed substantial changes in treatments that are particularly relevant for older patients.

Objectives

To assess changes in national-level incidence rates of fracture- and musculoskeletal-related (ie, arthritis-related) hip replacement procedures for individuals aged 40 to 104 years over a 23-year period in Denmark.

Design, Setting, and Participants

This cohort study used national Danish health registers to include the Danish population aged 40 to 104 years from January 1, 1996, to December 31, 2018. Data were analyzed from May 31, 2022, to February 14, 2024.

Main Outcomes and Measures

Age- and period-specific incidence rates of hip fracture and hip replacement stratified on fracture-related vs arthritis-related indication.

Results

From 1996 to 2018, a total of 3 664 979 individuals were followed up for a mean (SD) of 14.6 (7.7) years, resulting in a follow-up time of 53 517 861 person-years and 158 982 (first) hip fractures, of which 42 825 involved fracture-related hip replacement procedures. A further 104 422 individuals underwent arthritis-related hip replacement. During the first 2 decades of the 21st century, hip fracture rates declined by 35% to 40% for individuals aged 70 to 104 years, and the proportion of the population undergoing fracture-related hip replacement increased by 50% to 70%, with modest variation across those aged 75 to 99 years. Rates of arthritis-related hip replacements peaked for individuals aged 75 to 79 years, but with the largest relative rate increase (75%-100%) occurring for those aged 80 to 94 years, primarily from 2001 to 2015, whereafter it remained nearly unchanged. The decline in rates of arthritis-related hip replacement after 75 to 79 years of age was gradual and did not suggest an upper age limit for access to arthritis-related hip replacement.

Conclusions and Relevance

The findings of this cohort study suggest that during the past several decades in Denmark, the incidence of hip fractures declined by 35% to 40% among patients aged 80 to 104 years, while the proportion receiving fracture-related hip replacement remained relatively constant after 75 years of age. During the first decades of the 21st century, arthritis-related hip replacement incidence increased by 50% to 100% among older patients and stabilized hereafter, with no apparent cutoff age for this type of procedure. These patterns indicate a positive overall trend with declining hip fracture incidence over the last decades in Denmark, and the observed hip replacement incidence suggests that age is currently not a major determining factor guiding this type of surgery.

Experiences with and perception of patient-reported outcome measurement in patients undergoing knee and hip replacement in Germany

BACKGROUND

Patient-reported outcome measures - PROMs - have been developed to provide an assessment of patients' physical function, symptoms, and health-related quality of life. With patient-centered care becoming increasingly important, several national strategies have been initiated for PROM measurement. However, Germany is only at the beginning of this process. The objective of this study is to assess patients' experience with and perception of completing PROMs in patients undergoing knee and hip replacement in Germany.

METHODS

This study used survey data from patients undergoing hip or knee replacement surgery in a hospital in Germany. Before surgery, patients completed a PROMs survey. After at least 6 months, patients were re-contacted to fill in a questionnaire about their experiences with and perception of the PROMs data collection.

RESULTS

Most patients either agreed or totally agreed that the time to fill in the questionnaire was appropriate (89%), that the purpose of the PROMs collection was clear (85%), that the questionnaire's content applied to their appointment (73%), and that this systematic assessment was beneficial (81%). The corresponding proportions were 54% for feeling productive while waiting and 50% for feeling that the information in the questionnaire affected the patient-doctor interaction positively. Only few significant associations were found between patient characteristics and the favorability of patients' ratings. There were no significant differences between hip and knee replacement surgery patients regarding the favorability rating on any survey question.

CONCLUSIONS

The results of this study suggest that PROMs collection in the context of hip and knee replacement surgery is practicable and partly also perceived beneficial by patients. Orthopedic procedures could serve as a starting point for broader use and routine PROMs collection in Germany.

Understanding the 30-day mortality burden after revision total hip arthroplasty

BACKGROUND

Revision total hip arthroplasty (THA) is a challenging procedure that burdens the healthcare system. Despite being associated with worse outcomes relative to its primary counterpart, postoperative mortality after revision THA remains ill-defined. The present study aimed to (1) establish the overall 30-day mortality rate after revision THA and (2) explore the mortality rate stratified by age, comorbidity burden, and aseptic versus septic failure.

METHODS

The American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) database was retrospectively reviewed for all patients who underwent revision THA from 2011 to 2019. A total of 23,501 patients were identified and grouped into mortality (n = 161) and mortality-free (n = 23,340) cohorts. Patient demographics, comorbidities, and aseptic/septic failure were evaluated.

RESULTS

The overall 30-day mortality was 0.69%. The mortality rate by age group (normalised per 1000 patients) was 0 (18-39 years [Y]), 0.67 (40-49 Y), 1.10 (50-59 Y), 2.58 (60-69 Y), 6.15 (70-79 Y) 19.32 (80-89 Y), and 58.22 (90+Y) (p < 0.001). The mortality rate by ASA classification (normalised per 1000 patients) was 0 (ASA I), 1.47 (ASA II), 6.94 (ASA III), 45.42 (ASA IV), and 200 (ASA V) (p < 0.001). The 30-day mortality rate for the septic and aseptic cohorts was 1.03% and 0.65%, respectively (p = 0.038). CCI scores (p < 0.001), diabetes (p < 0.001), systematic sepsis (p < 0.001), poor functional status (p < 0.001), BMI < 24.9 kg/m2 (p < 0.001), and dirty/infected wounds (p < 0.001) were all associated with increased mortality risk.

CONCLUSIONS

1 in 145 patients will suffer mortality during the 30 days after revision THA. PJI-related revision THA was associated with 1.5-fold increase in 30-day mortality rate compared to its aseptic counterpart. Certain patient determinants and baseline comorbidities, as measured by ASA and CCI scores, were associated with higher 30-day mortality rates. Therefore, it is imperative to identify such risk factors and implement perioperative patient optimisation pathways to mitigate the risk among vulnerable patients.

Shape of the association between preoperative hemoglobin level and postoperative outcomes in patients undergoing primary arthroplasty

Background:

The shape of the association between preoperative hemoglobin level and outcomes after primary arthroplasty has not been adequately described. This study aimed to characterize the association between preoperative hemoglobin level and important outcomes after primary hip and knee arthroplasty and how this association is influenced by other key confounders.

Methods:

Using de-identified, population-based health administrative data for Ontario housed at ICES, we identified all primary hip and knee arthroplasty procedures performed in Ontario between April 2007 and March 2017. Preoperative hemoglobin level, age, sex, Charlson Comorbidity Index score, American Society of Anesthesiologists score, preadmission living status, Hospital-patient One-year Mortality Risk (HOMR) score, and serum sodium and creatinine levels were extracted. All relevant postoperative outcomes that could be measured accurately were identified. We performed multivariable logistic regression and restricted cubic splines analyses.

Results:

A total of 188 176 patients clustered within 532 surgeons were studied. The adjusted likelihood of transfusion increased notably and progressively when the preoperative hemoglobin level was below 135 g/L; duration of surgery, patient age and HOMR score amplified this association. Risk of postoperative admission to critical care showed a linear association with preoperative hemoglobin level. Risks of unplanned 30-day emergency department visit, 30-day readmission and 1-year all-cause mortality showed curvilinear associations with baseline hemoglobin level, with risks being notably greater as the level deviated from 137 g/L to 141 g/L.

Conclusion:

Preoperative hemoglobin levels, both high and low, were independently significantly associated with primary arthroplasty outcomes, and levels at which outcome risks started to increase exceeded threshold values commonly used to define “normal.” Preoperative hemoglobin level should be considered in future bundled payment models that aim to account for case-mix when grading postarthroplasty outcomes.

Good Outcome Scores and Low Conversion Rate to THA 10 Years After Hip Arthroscopy for the Treatment of Femoroacetabular Impingement

BACKGROUND

Arthroscopic treatment of symptomatic femoroacetabular impingement (FAI) has promising short-term to mid-term results. In addition to treating acute pain or impaired function, the goal of hip-preserving surgery is to achieve a lasting improvement of hip function and to prevent the development of osteoarthritis. Long-term results are necessary to evaluate the effectiveness of surgical treatment and to further improve results by identifying factors associated with conversion to THA.

QUESTIONS/PURPOSES

(1) How do the Merle d'Aubigné-Postel scores change from before surgery to follow-up of at least 10 years in patients undergoing hip arthroscopy for the treatment of FAI? (2) What is the cumulative 10-year survival rate of hips with the endpoints of conversion to THA or a Merle d'Aubigné-Postel score less than 15? (3) Which factors are associated with conversion to THA?

METHODS

Between 2003 and 2008, we treated 63 patients (65 hips) for symptomatic FAI with hip arthroscopy at our institution. During that period, the indications for using arthroscopy were correction of anterior cam morphology and anterolateral rim trimming with debridement or reattachment of the labrum. We excluded patients who were younger than 16 years and those who had previous trauma or surgery of the hip. Based on that, 60 patients (62 hips) were eligible. A further 17% (10 of 60) of patients were excluded because the treatment was purely symptomatic without treatment of cam- and/or pincer-type morphology. Of the 50 patients (52 hips) included in the study, 2% (1) of patients were lost before the minimum study follow-up of 10 years, leaving 49 patients (51 hips) for analysis. The median (range) follow-up was 11 years (10 to 17). The median age at surgery was 33 years (16 to 63). Ninety percent (45 of 50) of patients were women. Of the 52 hips, 75% (39 of 52) underwent cam resection (femoral offset correction), 8% (4 of 52) underwent acetabular rim trimming, and 17% (9 of 52) had both procedures. Additionally, in 35% (18 of 52) of hips the labrum was debrided, in 31% (16 of 52) it was resected, and in 10% (5 of 52) of hips the labrum was reattached. The primary clinical outcome measurements were conversion to THA and the Merle d'Aubigné-Postel score. Kaplan-Meier survivorship and Cox regression analyses were performed with endpoints being conversion to THA or Merle d'Aubigné-Postel score less than 15 points.

RESULTS

The clinical result at 10 years of follow-up was good. The median improvement of the Merle d'Aubigné-Postel score was 3 points (interquartile range 2 to 4), to a median score at last follow-up of 17 points (range 10 to 18). The cumulative 10-year survival rate was 92% (95% CI 85% to 99%) with the endpoints of conversion to THA or Merle d'Aubigné-Postel score less than 15. Factors associated with conversion to THA were each year of advancing age at the time of surgery (hazard ratio 1.1 [95% CI 1.0 to 1.3]; p = 0.01) and preoperative Tönnis Grade 1 compared with Tönnis Grade 0 (no sign of arthritis; HR 17 [95% CI 1.8 to 166]; p = 0.01).

CONCLUSION

In this series, more than 90% of patients retained their native hips and reported good patient-reported outcome scores at least 10 years after arthroscopic treatment of symptomatic FAI. Younger patients fared better in this series, as did hips without signs of osteoarthritis. Future studies with prospective comparisons of treatment groups are needed to determine how best to treat complex impingement morphologies.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

The influence of bearing surfaces on revisions due to dislocations in total hip arthroplasty

INTRODUCTION

Recurrent dislocations are still the most frequent reason for revision in total hip arthroplasty (THA). The impact of bearing surfaces on dislocations is still controversial. We hypothesized that: (1) bearing surfaces influence the revisions due to dislocations; (2) ceramic-on-ceramic reduced the revisions for dislocations in adjusted models; (3) Delta-on-Delta bearings reduced the revisions for dislocations in comparison to surfaces with cross-linked polyethylene.

MATERIALS AND METHODS

The regional arthroplasty registry was enquired about bearing surfaces and revisions for dislocations and instability. Unadjusted and adjusted rates were provided, including sex, age (<65 years or ≥65 years), head diameter (≤28 mm or >28 mm; <36 mm or ≥36 mm) as variables. 44,065 THAs were included.

RESULTS

The rate of revisions for dislocations was significantly lower in ceramic-on-ceramic and metal-on-metal bearings (unadjusted rates). After adjusting for age, sex, and head size (36 and 28 mm), hard-on-hard bearings were protective (p < 0.05): ceramic-on-ceramic had a lower risk of revisions due to dislocation than ceramic-on-polyethylene (HR 1.6, 95% CI 1.2-2.2 p = 0.0009). The rate of revisions for dislocation was similar in bearings with cross-linked polyethylene and Delta-on-Delta articulations, in unadjusted and adjusted models.

CONCLUSION

Bearings with conventional polyethylene were more predisposed to dislocations. Currently adopted bearings exerted no significant influence on revisions due to dislocations. These findings could be primarily related to wear, but due to the time distribution, soft tissue envelopes and surface tension may also play a role. Pre-clinical biomechanical evaluations and prospective matched cohort studies are required to draw definitive conclusions.

Closing the Socioeconomic Gap in Massachusetts: Trends in Total Hip Arthroplasty From 2013 to 2015

To extend insurance coverage to all residents, Massachusetts legislation expanded Medicaid eligibility and added new private insurance categories. To date, no one has analyzed the effect of these changes and compared recent trends in total hip arthroplasty (THA) utilization. Therefore, this study sought to update the current trends of THA utilization in Massachusetts from 2013 to 2015. The Massachusetts State Inpatient Database was queried for all patients who underwent primary THA between 2013 and 2015, and 30,308 patients were identified. Analyzed variables included age, sex, race, Charlson Comorbidity Index, median household income, primary payer, discharge disposition, length of stay, hospital charges, hospital costs, and complications. Categorical and continuous variables were assessed using chi-square analyses and analyses of variance, respectively. Between 2013 and 2015, annual THAs increased from 9361 to 10,562. Race did not vary significantly (P=.447), although an increase in patients using Medicaid and a decrease in patients using other insurance was observed (P<.001). Patients with an income quartile of 1 increased, whereas the number of THA patients in quartile 3 decreased (P<.001). There was a decrease in both hospital charges (P<.001) and costs (P<.001). Mean length of stay decreased (P<.001), and the number of patients with complications decreased (P<.001). Massachusetts has been successful in increasing access to THA procedures for low-income patients and increasing the number of patients who use Medicaid for THAs. The current delivery of health care in Massachusetts has shown improvement for its residents, serving as an example that other states can learn from. [Orthopedics. 2021;44(2):e167-e172.].

Mapping and Crosswalk of the Oxford Hip Score and Different Versions of the Hip Disability and Osteoarthritis Outcome Score

BACKGROUND

Patient-reported outcome measures such as the Oxford-12 Hip Score and Hip Disability and Osteoarthritis Outcome Score (HOOS) are used in daily orthopaedic practice to evaluate patients. Because different studies use different scores, it would be important to build conversion tables between scores (crosswalk) to compare the results of one study with those of another study. Various mapping methods can be used to develop crosswalk tables that convert Oxford-12 scores to the HOOS (and its derivatives, including the HOOS physical function short form, HOOS joint replacement, and HOOS-12) and vice versa. Although prior studies have investigated this issue, they are limited to short forms of the HOOS score. Consequently, they cannot be applied to hip preservation surgery and do not include quality-of-life items, whereas the Oxford-12 Hip Score is used for all hip evaluations.

QUESTIONS/PURPOSES

We prospectively studied the Oxford-12 and HOOS and its derivatives to (1) determine which version of the HOOS has the best mapping with the Oxford-12, (2) define the most-appropriate mapping method using selected indicators, and (3) generate crosswalk tables between these two patient-reported outcome measures.

METHODS

The study enrolled 500 adult patients before primary THA (59% men [294 of 500 patients]) with hip osteoarthritis or avascular necrosis of the femoral head who completed the HOOS and Oxford-12. Patients were recruited from January 2018 to September 2019 in a tertiary-care university hospital, and we included all primary THAs in patients older than 18 years with a BMI lower than 35 kg/m2 and greater than 18 kg/m2. After a minimum of 6 months of follow-up, 39% (195 of 500) of the patients were assessed using the same tools. To determine which version of the HOOS mapped best to the Oxford-12 and what the most-appropriate mapping method was, we used preoperative data from all 500 patients. Because there is no consensus on the method to establish crosswalk, various mapping methods (linear regression, tobit regression, and quantile regression) and equating methods (linear equating and equipercentile method) were applied along with cross-validation to determine which method was the most suitable and which form of the HOOS provided the best result according to different criteria (mean absolute error, r2, and Kolmogorov-Smirnov distance).To generate crosswalk tables, we created a conversion table (between the Oxford-12 and the HOOS form that was chosen after answering our first research question and the method chosen after answering our second question) using preoperative and postoperative data (n = 695). This table was meant to be simple to use and allows easy conversions from one scoring system to another.

RESULTS

The Oxford-12 and HOOS were strongly correlated (Pearson correlation coefficient range 0.586-0.842) for the HOOS subcategories and HOOS physical function, HOOS joint replacement, and HOOS-12. The correlation between the HOOS-12 and Oxford-12 was the strongest (r = 0.825). According to the three different criteria and five methods, the HOOS-12 was the best suited for mapping. The goal was to minimize the mean absolute error (perfect model = 0), have a Kolmogorov-Smirnov distance as close as possible to 0, and have the r2 as close as possible to 1. Regarding the most-suitable method for the crosswalk mapping (research question 2), the five methods generated similar results for the r2 (range 0.63-0.67) and mean absolute error (range 6-6.2). For the Kolmogorov-Smirnov distance, the equipercentile method was the best (Kolmogorov-Smirnov distance 0.04), with distance reduced by 43% relative to the regression methods (Kolmogorov-Smirnov distance 0.07). A graphical comparison of the predicted and observed scores showed that the equipercentile method provided perfect superposition of predicted and observed values after mapping. Finally, crosswalk tables were produced between the HOOS-12 and Oxford-12.

CONCLUSION

The HOOS-12 is the most complete and suitable form of the HOOS for mapping with the Oxford-12, while the equipercentile method is the most suitable for predicting values after mapping. This study provides clinicians with a reliable tool to crosswalk between these scores not only for joint arthroplasty but also for all types of hip surgeries while also assessing quality of life. Our findings should be confirmed in additional studies.

CLINICAL RELEVANCE

The resulting crosswalk tables can be used in meta-analyses, systematic reviews, or clinical practice to compare clinical studies that did not include both outcome scores. In addition, with these tools, the clinician can collect only one score while still being able to compare his or her results with those obtained in other databases and registries, and to add his or her results to other databases and joint registries.

Is the Proportion of Patients with "Successful" Outcomes After Two-stage Revision for Prosthetic Joint Infection Different When Applying the Musculoskeletal Infection Society Outcome Reporting Tool Compared with the Delphi-based Consensus Criteria?

BACKGROUND

There are a variety of criteria for defining successful treatment after two-stage exchange arthroplasty for prosthetic joint infection (PJI). To accurately assess current practices and improve techniques, it is important to first establish reliable, clinically relevant, reproducible criteria for defining persistent infection and "successful" outcomes.

QUESTION/PURPOSE

Is the proportion of patients considered to have successful management of PJI after two-stage resection arthroplasty smaller using 2019 Musculoskeletal Infection Society Outcome Reporting Tool (MSIS ORT) criteria than when using a Delphi-based criterion?

METHODS

Patients were retrospectively identified by Current Procedural Technology codes for resection arthroplasty with placement of an antibiotic spacer for infected THA or TKA between April 1, 2011 and January 1, 2018 at a tertiary academic institution. The initial review identified 180 procedures during this time period. Nine patients had documented transition of care outside the system, 16 did not meet the MSIS criteria for chronic PJI, and 34 patients were excluded for lack of documented 2-year follow-up. The mean follow-up duration of the final cohort of 121 procedures in 120 patients was approximately 3.7 ± 1.7 years. Forty percent (49 of 121) of the procedures were performed on the hip and 60% (72 of 121) were performed on the knee. The mean time from primary THA or TKA to explantation was 4.6 years. The mean age of the patients at the time of explantation was 66 years. The mean time from spacer placement to replantation was 119 days. The final 121 patient records were reviewed by a single reviewer and outcomes were subsequently assigned to "successful" and "unsuccessful" outcomes based on the MSIS ORT and Delphi-based consensus criterion, two previously published and validated multidimensional definition schemes. Chi-squared and t-test analyses were performed to identify differences between "successful" and "unsuccessful" outcomes with respect to patient baseline characteristics using each outcome-reporting criterion.

RESULTS

Overall, the MSIS ORT classified a smaller proportion of patients as having a "successful" treatment outcome after two-stage exchange arthroplasty for PJI than the Delphi-based consensus method did (MSIS: 55% [63 of 114], Delphi: 70% [71 of 102]; relative risk 0.79 [0.65-0.98]; p = 0.03). However, there were no differences when stratified by hips (MSIS: 55% [26 of 47], Delphi: 74% [29 of 39]; relative risk 0.74 [0.54-1.02]; p = 0.07) and knees (MSIS: 55% [37 of 67], Delphi: 67% [42 of 63]; relative risk 0.83 [0.63-1.09]; p = 0.19). Notably, the disease of 16% of the patients (19 of 121) was not classifiable per the Delphi method because these patients never underwent reimplantation.

CONCLUSION

The present study demonstrated that the MSIS criteria detect fewer instances of "successful" infection management after two-stage resection arthroplasty for PJI than the Delphi method in this cohort. Based on these findings, researchers and surgeons should aim for standardized reporting after intervention for PJI to allow for a better comparison of outcomes across different studies and ultimately allow for improved techniques and approaches to the treatment of PJI.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Association of Sex With Risk of 2-Year Revision Among Patients Undergoing Total Hip Arthroplasty

IMPORTANCE

The worldwide population is aging and includes more female individuals than male individuals, with higher rates of total hip arthroplasty (THA) among female individuals. Although research on this topic has been limited to date, several studies are currently under way.

OBJECTIVES

To evaluate the association between sex and 2-year revision after THA.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from statewide databases in New York and California between October 1, 2015, and December 31, 2018. Patients 18 years or older with osteoarthritis who underwent THA and had sex recorded in the database were included in the analysis.

EXPOSURE

Total hip arthroplasty.

MAIN OUTCOMES AND MEASURES

The outcome of interest was the difference in early, all-cause revision surgery rates after primary THA between women and men. The association of sex with the revision rate was examined using Cox proportional hazards regression analysis.

RESULTS

Of 132 826 patients included in the study, 74 002 (55.7%) were women; the mean (SD) age was 65.9 (11.0) years, and the median follow-up time was 1.3 years (range, 0.0-3.0 years). The 2-year revision rate was 2.5% (95% CI, 2.4%-2.6%) among women and 2.1% (95% CI, 2.0%-2.2%) among men. After adjusting for demographic characteristics, comorbidities, and facility volume, a minimal clinically meaningful difference was observed in revision rates despite women having a higher risk of all-cause revision compared with men (hazard ratio, 1.16; 95% CI, 1.07-1.26; P < .001). The risk of revision was increased among women compared with men in the subgroup of patients who were younger than 55 years (hazard ratio, 1.47; 95% CI, 1.20-1.81; P < .001).

CONCLUSIONS AND RELEVANCE

In this cohort study, no clinically meaningful difference in all-cause revision rates after primary THA was found between men and women at 2-year follow-up. The modest difference in the risk of revision between men and women in a small subgroup of patients younger than 55 years suggests that the risk of revision in this population should be studied further.

Compensation claims after hip arthroplasty surgery in Norway 2008-2018

Background and purpose - Orthopedic surgery is one of the specialties with most compensation claims, therefore we assessed the most common reasons for complaints following total hip arthroplasty (THA) reported to the Norwegian System of Patient Injury Compensation (NPE) and viewed these complaints in light of the data from the Norwegian Arthroplasty Register (NAR).Patients and methods - We collected data from NPE and NAR for the study period (2008-2018), including age, sex, and type of complaint, and reason for accepted claims from NPE, and the number of arthroplasty surgeries from NAR. The institutions were grouped by quartiles into quarters according to annual procedure volume, and the effect of hospital procedure volume on the risk for accepted claim was estimated.Results - 70,327 THAs were reported to NAR. NPE handled 1,350 claims, corresponding to 1.9% of all reported THAs. 595 (44%) claims were accepted, representing 0.8% of all THAs. Hospital-acquired infection was the most common reason for accepted claims (34%), followed by wrong implant position in 11% of patients. Low annual volume institutions (less than 93 THAs per year) had a statistically significant 1.6 times higher proportion of accepted claims compared with higher volume institutions.Interpretation - The 0.8% risk of accepted claims following THAs is 1.6 times higher for patients treated in low-volume institutions, which should consider increasing the volume of THAs or referring these patients to higher volume institutions.

Association of the Comprehensive Care for Joint Replacement Model With Disparities in the Use of Total Hip and Total Knee Replacement

IMPORTANCE

The Comprehensive Care for Joint Replacement (CJR) model is Medicare's mandatory bundled payment reform to improve quality and spending for beneficiaries who need total hip replacement (THR) or total knee replacement (TKR), yet it does not account for sociodemographic risk factors such as race/ethnicity and income. Results of this study could be the basis for a Medicare payment reform that addresses inequities in joint replacement care.

OBJECTIVE

To examine the association of the CJR model with racial/ethnic and socioeconomic disparities in the use of elective THR and TKR among older Medicare beneficiaries after accounting for the population of patients who were at risk or eligible for these surgical procedures.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used the 2013 to 2017 national Medicare data and multivariable logistic regressions with triple-differences estimation. Medicare beneficiaries who were aged 65 to 99 years, entitled to Medicare, alive at the end of the calendar year, and residing either in the 67 metropolitan statistical areas (MSAs) mandated to participate in the CJR model or in the 104 control MSAs were identified. A subset of Medicare beneficiaries with a diagnosis of arthritis underwent THR or TKR. Data were analyzed from March to December 2020.

EXPOSURES

Implementation of the CJR model in 2016.

MAIN OUTCOMES AND MEASURES

Outcomes were separate binary indicators for whether a beneficiary underwent THR or TKR. Key independent variables were MSA treatment status, pre- or post-CJR model implementation phase, combination of race/ethnicity (non-Hispanic White, non-Hispanic Black, and Hispanic beneficiaries) and dual eligibility, and their interactions. Logistic regression models were used to control for patient characteristics, MSA fixed effects, and time trends.

RESULTS

The 2013 cohort included 4 447 205 Medicare beneficiaries, of which 2 025 357 (45.5%) resided in MSAs with the CJR model. The cohort's mean (SD) age was 77.18 (7.95) years, and it was composed of 2 951 140 female (66.4%), 3 928 432 non-Hispanic White (88.3%), and 657 073 dually eligible (14.8%) beneficiaries. Before the CJR model implementation, rates were highest among non-Hispanic White non-dual-eligible beneficiaries at 1.25% (95% CI, 1.24%-1.26%) for THR use and 2.28% (95% CI, 2.26%-2.29%) for TKR use in MSAs with CJR model. Compared with MSAs without the CJR model and the analogous race/ethnicity and dual-eligibility group, the CJR model was associated with a 0.10 (95% CI, 0.05-0.15; P < .001) percentage-point increase in TKR use for non-Hispanic White non-dual-eligible beneficiaries, a 0.11 (95% CI, 0.004-0.21; P = .04) percentage-point increase for non-Hispanic White dual-eligible beneficiaries, a 0.15 (95% CI, -0.29 to -0.01; P = .04) percentage-point decrease for non-Hispanic Black non-dual-eligible beneficiaries, and a 0.18 (95% CI, -0.34 to -0.01; P = .03) percentage-point decrease for non-Hispanic Black dual-eligible beneficiaries. These CJR model-associated changes in TKR use were 0.25 (95% CI, -0.40 to -0.10; P = .001) percentage points lower for non-Hispanic Black non-dual-eligible beneficiaries and 0.27 (95% CI, -0.45 to -0.10; P = .002) percentage points lower for non-Hispanic Black dual-eligible beneficiaries compared with the model-associated changes for non-Hispanic White non-dual-eligible beneficiaries. No association was found between the CJR model and a widening of the THR use gap among race/ethnicity and dual eligibility groups.

CONCLUSIONS AND RELEVANCE

Results of this study indicate that the CJR model was associated with a modest increase in the already substantial difference in TKR use among non-Hispanic Black vs non-Hispanic White beneficiaries; no difference was found for THR. These findings support the widespread concern that payment reform has the potential to exacerbate disparities in access to joint replacement care.

Preoperative risk factors in hip arthroscopy

PURPOSE

Arthroscopic surgery is a usual technique to repair hip femoroacetabular impingement. Correlation exists among surgical indication, postoperative evolution, the final result, and the necessity of prosthesis in the near future. The assessment of specific parameters allowing us to evaluate the prognosis becomes vital to improve the results. The objective of this study is to check the variables found in patients with femoroacetabular impingement (FAI) treated with hip arthroscopy, and determine which of these variables would serve as key indicators in predicting the need for subsequent arthroplasty.

METHODS

Data from FAI surgical indications (age, weight, height, BMI, gender, side, radiographic Tönnis degree, cartilage lesion degree by Acetabular Labrum Articular Disruption (ALAD) degree, VAS value, HOS, mHHS and WOMAC) were collected from cases which should have had a minimum monitoring period of 2 years from 2007 to 2017. The results of the group which needed prosthesis were compared to the results of the ones who did not.

RESULTS

Among 452 patients who were monitored for an average of 5.8 years, 82 (18.1%) required conversion to prosthesis. The variables that indicated relatively high risk were fourth-degree acetabular labrum articular disruption (ALAD) chondral injury, preoperative radiographic Grade 2 Tönnis classification, age of over 55 years, WOMAC over 45 points, and HOS-ADL under 50 points. There were no significant differences between side, gender, VAS level, nor HOS.

CONCLUSIONS

The presence of chondral injuries such as acetabular labrum articular disruption (ALAD) 4, radiographic Grade 2 Tönnis classification, higher age, higher BMI, and worse WOMAC, along with mHHS and HOS-ADL preoperative results, are factors which lead to a poor prognosis following FAI hip arthroscopic surgery, increasing the risk of prosthetic conversion in the short or medium term.

LEVEL OF EVIDENCE

Level IV.

Cementless ceramic-on-ceramic total hip arthroplasty in post-traumatic osteoarthritis after acetabular fracture: long-term results

INTRODUCTION

Total hip arthroplasty (THA) is the standard procedure for post-traumatic osteoarthritis (OA) of the hip after acetabular fracture. However, it is not as simple as a primary THA, challenging the surgeon with anatomical deformity and intra and postoperative complications. In the current literature, there is a lack of studies reporting long-term results. May ceramic-on-ceramic (CoC) bearings provide good clinical and radiological outcomes at a long-term follow-up in patients undergoing THA following acetabular fracture?

MATERIALS AND METHODS

We retrospectively analyzed 68 patients (mean age 47 years [range 22-75)] who underwent cementless modular neck stem THA, all implants CoC bearings (50 previously operatively treated and 18 non-operatively treated) after a specific CT study protocol at our Institute since 2000-2008. Clinical outcomes, prosthetic components' osseointegration, survival rate, and reasons for revision were analyzed. Minimum clinical and radiological follow-up was 10 years.

RESULTS

HHS improved significantly after surgery from 37.6 ± 14.1 to 88.4 ± 11.6. 8 revision surgeries were performed, none for infection: we reported 2 stem aseptic loosening, 2 periprosthetic femoral fractures and 4 modular neck fractures. One implant noise (third-generation ceramic coupling) was described. Cup osseointegration was present (according to Moore the presence of at least 3 radiological criteria defines an effective osseointegration) in 67 patients (98.5%). After a 10 years follow-up, survival rate resulted 88.4%, sensibly higher than most of results reported in the current literature.

CONCLUSION

The high survival rate may be related to CoC: no osteolysis and no infections were reported. Also acetabular cup loosening incidence was sensibly lower (1.47%) among loosening rate described by other authors. Clinical and radiological outcomes were decent, probably due to modular prosthesis design. Modular necks are a solution which can help achieving a proper functional reconstruction of the hip (offset, center of rotation), but should be avoided in young and overweight patients because of the high risk of fracture. CoC bearings in THAs in post-traumatic OA after acetabular fracture showed good results despite the fact that specific ceramic-related issues have to be considered.

Comparison of clinical outcomes with hip replacement versus PFNA in the treatment of intertrochanteric fractures in the elderly: A systematic review and meta-analysis (PRISMA)

BACKGROUND

The purpose of this meta-analysis was to evaluate the clinical efficacy and safety of HR and PFNA in the treatment of intertrochanteric fractures in the elderly.

METHODS

We carried out this review according to the principle of preferred reporting items for systematic reviews and meta-analyses (PRISMA) guideline. The clinical randomized controlled trials (RCTs), prospective cohort studies, retrospective cohort studies (RCSs), and case-control studies involving HR and PFNA in the treatment of intertrochanteric fractures in the elderly from 2000 to 2020 were compared by searching Web of Science, Pubmed, the Cochrane Library, and Embase. The quality of the included cohort study (CS) lines was evaluated using the Newcastle-Ottawa Scale (NOS). The quality of the included RCT lines was evaluated using Jadad. Forest plots were drawn by RevMan5.4 software based on the results and the data were analyzed.

RESULTS

After screening, a total of 9 articles were included, of which one was a clinical RCT and eight were RCSs with 1374 patients. The operative time of the PFNA group was shorter [WMD = 15.20; 95% CI (13.17, 17.23), P < .05] and the intraoperative blood loss was less [WMD = 178.81; 95% CI (97.24, 260.38), P < .05] than the HR group, while the first weight-bearing time of the HR group was shorter [WMD = -7.70; 95% CI (-10.54, -4.86), P  < .05] than the PFNA group. There was no significant difference in the length of hospital stay, HHS, postoperative orthopedic complications, and postoperative medical complications between the 2 groups.

CONCLUSION

With the development of HR technology and minimally invasive technology, the trauma caused by surgery is decreasing. Under the premise of improving perioperative management, such as optimizing the preoperative preparation and postoperative management, shortening the operative time, reducing intraoperative blood loss, and actively managing co-existing diseases, HR has more advantages than PFNA in the treatment of senile intertrochanteric fractures.

Assessment of Extractability and Accuracy of Electronic Health Record Data for Joint Implant Registries

IMPORTANCE

Implant registries provide valuable information on the performance of implants in a real-world setting, yet they have traditionally been expensive to establish and maintain. Electronic health records (EHRs) are widely used and may include the information needed to generate clinically meaningful reports similar to a formal implant registry.

OBJECTIVES

To quantify the extractability and accuracy of registry-relevant data from the EHR and to assess the ability of these data to track trends in implant use and the durability of implants (hereafter referred to as implant survivorship), using data stored since 2000 in the EHR of the largest integrated health care system in the United States.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of a large EHR of veterans who had 45 351 total hip arthroplasty procedures in Veterans Health Administration hospitals from 2000 to 2017. Data analysis was performed from January 1, 2000, to December 31, 2017.

EXPOSURES

Total hip arthroplasty.

MAIN OUTCOMES AND MEASURES

Number of total hip arthroplasty procedures extracted from the EHR, trends in implant use, and relative survivorship of implants.

RESULTS

A total of 45 351 total hip arthroplasty procedures were identified from 2000 to 2017 with 192 805 implant parts. Data completeness improved over the time. After 2014, 85% of prosthetic heads, 91% of shells, 81% of stems, and 85% of liners used in the Veterans Health Administration health care system were identified by part number. Revision burden and trends in metal vs ceramic prosthetic femoral head use were found to reflect data from the American Joint Replacement Registry. Recalled implants were obvious negative outliers in implant survivorship using Kaplan-Meier curves.

CONCLUSIONS AND RELEVANCE

Although loss to follow-up remains a challenge that requires additional attention to improve the quantitative nature of calculated implant survivorship, we conclude that data collected during routine clinical care and stored in the EHR of a large health system over 18 years were sufficient to provide clinically meaningful data on trends in implant use and to identify poor implants that were subsequently recalled. This automated approach was low cost and had no reporting burden. This low-cost, low-overhead method to assess implant use and performance within a large health care setting may be useful to internal quality assurance programs and, on a larger scale, to postmarket surveillance of implant performance.

Development and Alpha Testing of Specifications for a Prolonged Opioid Prescribing Electronic Clinical Quality Measure (eCQM)

Brigham and Women's Hospital (BWH) has received funding from the Centers for Medicare and Medicaid Services (CMS) to design and implement an electronic clinical quality measure (eCQM) assessing the rate of prolonged opioid prescribing practices following Total Hip Arthroplasty (THA) and Total Knee Arthroplasty (TKA). Utilizing an existing guideline, 'prolonged prescribing' has been defined as opioid prescriptions that exceed 42 days (6 weeks) following surgery. This measure was tested on 12,803 Partners' Healthcare (PHS) patients. Findings demonstrated that after 42 days, meeting the criteria for 'prolonged prescribing' as defined by the proposed measure, 3.7% of THA patients and 12.1% of TKA patients were still receiving opioids. With a better understanding of how specific clinician group post-operative prescribing practices compare with their peers and incorporating monetary incentives through the MIPS participation pathway of the Quality Payment Program (QPP), this measure will motivate orthopedic practices to improve their prescribing patterns, ultimately driving evidence-based quality improvement.

Assessing the Efficacy of Certificate of Need Laws Through Total Joint Arthroplasty

ABSTRACT

Lawmakers suggest Certificate of Need (CON) laws' main goals are increasing access to healthcare, increasing quality of healthcare, and decreasing healthcare costs. This retrospective database study aims to evaluate the effectiveness of CON through analysis of total knee, hip, and shoulder arthroplasty (TKA, THA, and TSA, respectively). A review was performed using the Humana Insurance PearlDiver national database from 2007 to 2015. Access to care was approximated by the rates of total joint arthroplasty (TJA) in patients diagnosed with arthritis to the corresponding joint. The quality of care was assessed using complication rates after TJA. The total cost of TJA was approximated from average reimbursement to the healthcare facility per procedure. Patients in states without CON programs received TKA, THA, and TSA more frequently (p < .0001, p = .250, p = .019). No significant difference was found in studied complication rates between CON and non-CON states. Similarly, there was no trend found when comparing the cost of each procedure in CON versus non-CON states. These findings are consistent with other recent studies detailing the impact of CON regulation on THA and TKA. The apparent nonsuperiority of CON states in achieving their purported goals may call into question the effectiveness of additional bureaucracy and regulation, suggesting a need for further examination.

Current and Future Burden of Periprosthetic Joint Infection from National Claim Database

BACKGROUND

Periprosthetic joint infection (PJI) is the most serious complication after total joint arthroplasty. The incidence and burden of PJI in North America have been reported. There might be potential differences according to ethnics and regional practices between western countries and East Asia. Nevertheless, its incidence in East Asia remains unknown. We aimed to evaluate the incidence and economic burden of PJI in Korea and to project the future burden.

METHODS

We identified numbers of total hip arthroplasties, total knee arthroplasties and PJIs in Korea from 2010 to 2018 using medical claim data of Korean Health Insurance and Review and Assessment. Annual incidence and medical cost of PJI were calculated. We projected future burden of PJI through 2030 using Quasi-poisson regression model.

RESULTS

The annual incidence of PJI ranged from 2.3% to 2.8% and the average cost per each PJI patient ranged from $4,361 to $6,016. Total annual cost of PJI increased from $8.0 million in 2010 to $18.0 million in 2018 and was projected to exceed $57.0 million by 2030.

CONCLUSION

The incidence of PJI in Korea is comparable with reported PJI incidence of 2.0%-2.7% in the United States. Our findings would be used for worldwide comparison of PJI epidemiology and establishment of healthcare policies for PJI in East Asia.

A systematic review and meta-analysis of fall incidence and risk factors in elderly patients after total joint arthroplasty

BACKGROUND

Falls in the elderly have become a serious social problem worldwide. Approximately a third of persons fall at least once in the year after total joint arthroplasty (TJA), but preventing and treating falls is still challenging in clinical practice. Until now, no formal systematic review or meta-analysis was performed to summarize the risk factors of falls after TJA. The present study aimed to quantitatively and comprehensively conclude the risk factors of falls after TJA in elderly patients.

METHODS

The electronic databases to be searched include CNKI, Embase, Medline, and Cochrane central database (all up to November 2018). All studies on the risk factors of falls after TJA in elderly patients without language restriction were reviewed. Process of evaluation of identified studies and extraction of data were independently conducted by 2 reviewers, qualities of included studies were assessed using the Newcastle-Ottawa Scale. Data were pooled and a meta-analysis completed. All analyses were performed by the software Stata 11.0.

RESULTS

A total of 14 studies were included, which altogether included 1284456 patients with TJA, of them 12879 cases of falls occurred after surgery, suggesting the accumulated incidence of 13.1% and the prevalence of in-hospital falls was 1.0%. This study has provided evidence for the preventing of falls in the elderly patients who were underwent TJA. Outcome measures include advanced age, female, Overweight (BMI≥25 kg/m), falls history, use of walking aid, diabetes, cardiac disease, hypertension, COPD and depressive symptoms. The ABC Scale was significantly negatively correlated with falls after lower extremity joint replacement.

CONCLUSIONS

Related prophylaxis strategies should be implemented in elderly patients involved with above-mentioned risk factors to prevent falls after TJA.

The incidence of shoulder arthroplasty: rise and future projections compared with hip and knee arthroplasty

BACKGROUND

There remains a paucity of epidemiologic data from recent years on the incidence of shoulder arthroplasty. We aimed to examine the recent trends and predict future projections of hemiarthroplasty (HA), anatomic (aTSA), and reverse shoulder arthroplasty (RSA), as well as compare these predictions to those for total hip (THA) and knee arthroplasty (TKA).

METHODS

The National Inpatient Sample was queried from 2011 to 2017 for HA, aTSA, and RSA, as well as TKA and THA. Linear and Poisson regression was performed to project annual procedural incidence and volume to the year 2025.

RESULTS

Between 2011 and 2017, the number of primary shoulder arthroplasties increased by 103.7%. In particular, RSA increased by 191.3%, with 63,845 RSAs performed in 2017. All projection models demonstrated significant increases in shoulder arthroplasty volume and incidence from 2017 to 2025. By 2025, the linear model predicts that shoulder arthroplasty volume will increase by 67.2% to 174,810 procedures whereas the Poisson model predicts a 235.2% increase, to 350,558 procedures by 2025. These growth rate projections outpace those of THA and TKA.

CONCLUSIONS

The number of shoulder arthroplasties has been increasing in recent years, largely because of the exponential increases in RSA. The overall incidence is increasing at a greater rate than TKA or THA, with projections continuing to rise over the next decade. These data and projections can be used by policy makers and hospitals to drive initiatives aimed at meeting these projected future demands.

Quality Measure Public Reporting Is Associated with Improved Outcomes Following Hip and Knee Replacement

BACKGROUND

Given the inclusion of orthopaedic quality measures in the Centers for Medicare & Medicaid Services national hospital payment programs, the present study sought to assess whether the public reporting of total hip arthroplasty (THA) and total knee arthroplasty (TKA) risk-standardized readmission rates (RSRRs) and complication rates (RSCRs) was temporally associated with a decrease in the rates of these outcomes among Medicare beneficiaries.

METHODS

Annual trends in national observed and hospital-level RSRRs and RSCRs were evaluated for patients who underwent hospital-based inpatient hip and/or knee replacement procedures from fiscal year 2010 to fiscal year 2016. Hospital-level rates were calculated with use of the same measures and methodology that were utilized in public reporting. Annual trends in the distribution of hospital-level outcomes were then examined with use of density plots.

RESULTS

Complication and readmission rates and variation declined steadily from fiscal year 2010 to fiscal year 2016. Reductions of 33% and 25% were noted in hospital-level RSCRs and RSRRs, respectively. The interquartile range decreased by 18% (relative reduction) for RSCRs and by 34% (relative reduction) for RSRRs. The frequency of risk variables in the complication and readmission models did not systematically change over time, suggesting no evidence of widespread bias or up-coding.

CONCLUSIONS

This study showed that hospital-level complication and readmission rates following THA and TKA and the variation in hospital-level performance declined during a period coinciding with the start of public reporting and financial incentives associated with measurement. The consistently decreasing trend in rates of and variation in outcomes suggests steady improvements and greater consistency among hospitals in clinical outcomes for THA and TKA patients in the 2016 fiscal year compared with the 2010 fiscal year. The interactions between public reporting, payment, and hospital coding practices are complex and require further study.

LEVEL OF EVIDENCE

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

Blood loss in primary total hip arthroplasty with a short versus conventional cementless stem: a retrospective cohort study

INTRODUCTION

To evaluate the impact of short cementless stem on several clinical and radiographic outcomes, with particular focus on blood loss, in comparison with conventional cementless stem in total hip arthroplasty (THA).

MATERIALS AND METHODS

Patients undergoing THA with GTS short stem or CLS conventional stem were included. Clinical data were retrospectively collected including preoperative and postoperative day 1 value for haemoglobin (HB); rate of postoperative blood transfusions; intraoperative bone infractions; stem alignment; 5-year follow-up Harris Hip Score (HHS) and rate of stem revision at 5 years of follow-up of the short and conventional cementless stem.

RESULTS

GTS and CLS stem group included 374 and 321 patients, respectively. The mean difference between the preoperative and postoperative day 1 HB value was 3.98 g/dL (SD 1.12) and 3.67 g/dL (SD 1.19) in the GTS and CLS group, respectively, which correspond to a crude effect (β) of 0.32 (95% CI 0.15; 0.49) and adjusted effect of 0.11 (95% CI - 0.08; 0.3). GTS group reported a significantly higher number of patients with excellent results in terms of HHS (p = 0.001). The rate of intraoperative bone infractions was 1.6% and 0.3% in the GTS and CLS group, respectively (p = 0.013). At radiographic assessment, the rate of varus position of the stem was 14% in the GTS group and 6% in the CLS group (p < 0.0001). The rate of stem revision at 5 years of follow-up was 0.8% and 0.4% in the GTS and CLS group, respectively (p = 0.63).

CONCLUSIONS

GTS short stem was not associated with a clinically significant lower blood loss in the immediately postoperative period. Unadjusted exploratory analyses show that GTS stem provides the same results of CLS stem in terms of HHS and rate of stem revision at 5 years of follow-up.

Regional variation in hip and knee arthroplasty rates in Switzerland: A population-based small area analysis

Background

Compared to other OECD countries, Switzerland has the highest rates of hip (HA) and knee arthroplasty (KA).

Objective

We assessed the regional variation in HA/KA rates and potential determinants of variation in Switzerland.

Methods

We conducted a population-based analysis using discharge data from all Swiss hospitals during 2013–2016. We derived hospital service areas (HSAs) by analyzing patient flows. We calculated age-/sex-standardized procedure rates and measures of variation (the extremal quotient [EQ, highest divided by lowest rate] and the systemic component of variation [SCV]). We estimated the reduction in variance of HA/KA rates across HSAs in multilevel regression models, with incremental adjustment for procedure year, age, sex, language, urbanization, socioeconomic factors, burden of disease, and the number of orthopedic surgeons.

Results

Overall, 69,578 HA and 69,899 KA from 55 HSAs were analyzed. The mean age-/sex-standardized HA rate was 265 (range 179–342) and KA rate was 256 (range 186–378) per 100,000 persons and increased over time. The EQ was 1.9 for HA and 2.5 for KA. The SCV was 2.0 for HA and 2.2 for KA, indicating a low variation across HSAs. When adjusted for procedure year and demographic, cultural, and sociodemographic factors, the models explained 75% of the variance in HA and 63% in KA across Swiss HSAs.

Conclusion

Switzerland has high HA/KA rates with a modest regional variation, suggesting that the threshold to perform HA/KA may be uniformly low across regions. One third of the variation remained unexplained and may, at least in part, represent differing physician beliefs and attitudes towards joint arthroplasty.

Association of Medicare Mandatory Bundled Payment System for Hip and Knee Joint Replacement With Racial/Ethnic Difference in Joint Replacement Care

IMPORTANCE

There are marked racial/ethnic differences in hip and knee joint replacement care as well as concerns that value-based payments may exacerbate existing racial/ethnic disparities in care.

OBJECTIVE

To examine changes in joint replacement care associated with Medicare's Comprehensive Care for Joint Replacement (CJR) model among White, Black, and Hispanic patients.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of Medicare claims from 2013 through 2017 among White, Black, and Hispanic patients undergoing joint replacement in 67 treatment (selected for CJR participation) and 103 control metropolitan statistical areas.

EXPOSURES

The CJR model holds hospitals accountable for spending and quality of joint replacement care during care episodes (index hospitalization through 90 days after discharge).

MAIN OUTCOMES AND MEASURES

The primary outcomes were spending, discharge to institutional postacute care, and readmission during care episodes.

RESULTS

Among 688 346 patients, 442 163 (64.2%) were women, and 87 286 (12.7%) were 85 years or older. Under CJR, spending decreased by $439 for White patients (95% CI, -$718 to -$161; from pre-CJR spending in treatment metropolitan statistical areas of $25 264) but did not change for Black patients and Hispanic patients. Discharges to institutional postacute care decreased for all groups (-2.5 percentage points; 95% CI, -4.7 to -0.4, from pre-CJR risk of 46.2% for White patients; -6.0 percentage points; 95% CI, -9.8 to -2.2, from pre-CJR risk of 59.5% for Black patients; and -4.3 percentage points; 95% CI, -7.6 to -1.0, from pre-CJR risk of 54.3% for Hispanic patients). Readmission risk decreased for Black patients by 3.1 percentage points (95% CI, -5.9 to -0.4, from pre-CJR risk of 21.8%) and did not change for White patients and Hispanic patients. Under CJR, Black-White differences in discharges to institutional postacute care decreased by 3.4 percentage points (95% CI, -6.4 to -0.5, from the pre-CJR Black-White difference of 13.3 percentage points). No evidence was found demonstrating that Black-White differences changed for other outcomes or that Hispanic-White differences changed for any outcomes under CJR.

CONCLUSIONS AND RELEVANCE

In this cohort study of patients receiving joint replacements, CJR was associated with decreased readmissions for Black patients. Furthermore, Black patients experienced a greater decrease in discharges to institutional postacute care relative to White patients, representing relative improvements despite concerns that value-based payment models may exacerbate existing disparities. Nonetheless, differences between White and Black patients in joint replacement care still persisted even after these changes.

Can vertically integrated health systems provide greater value: The case of hospitals under the comprehensive care for joint replacement model?

OBJECTIVE

We aim to assess whether system providers perform better than nonsystem providers under an alternative payment model that incentivizes high-quality, cost-efficient care. We posit that the payment environment and the incentives it provides can affect the relative performance of vertically integrated health systems. To examine this potential influence, we compare system and nonsystem hospitals participating in Medicare's Comprehensive Care for Joint Replacement (CJR) model.

DATA SOURCES

We used hospital cost and quality data from the Centers for Medicare & Medicaid Services linked to data from the Agency for Healthcare Research and Quality's Compendium of US Health Systems and hospital characteristics from secondary sources. The data include 706 hospitals in 67 metropolitan areas.

STUDY DESIGN

We estimated regressions that compared system and nonsystem hospitals' 2017 cost and quality performance providing lower joint replacements among hospitals required to participate in CJR.

PRINCIPAL FINDINGS

Among CJR hospitals, system hospitals that provided comprehensive services in their local market had 5.8 percent ($1612) lower episode costs (P = .01) than nonsystem hospitals. System hospitals that did not provide such services had 3.5 percent ($967) lower episode costs (P = .14). Quality differences between system hospitals and nonsystem hospitals were mostly small and statistically insignificant.

CONCLUSIONS

When operating under alternative payment model incentives, vertical integration may enable hospitals to lower costs with similar quality scores.

Repeated cobalt and chromium ion measurements in patients with bilateral large-diameter head metal-on-metal ReCap-M2A-Magnum total hip replacement

Background and purpose - Whole-blood (WB) chromium (Cr) and cobalt (Co) measurements are vital in the follow-up of metal-on-metal total hip replacement (MoM THR) patients. We examined whether there is a substantial change in repeated WB, Co, and Cr levels in patients with bilateral ReCap-M2A-Magnum THR. We also specified the number of patients exceeding the safe upper limit (SUL) of WB Co and Cr in the repeated measurement.Patients and methods - We identified 141 patients with bilateral ReCap-M2A-Magnum THR operated in our institution. 61 patients had repeated WB metal ion measurements with bilateral MoM implants still in situ in the second measurement. The mean time elapsing from the first measurement (initial measurement) to the second (control measurement) was 1.9 years (SD = 0.6, range 0.2-3.5). We used earlier established SUL levels for bilateral implants by Van Der Straeten et al. (2013).Results - The median (range) Co and Cr values decreased in the repeated measurement from 2.7 (0.6-25) to 2.1 (0.5-21) and 2.6 (0.8-14) to 2.1 (0.5-18) respectively. In 13% of the patients Co levels exceeded the SUL in the initial measurement and the proportion remained constant, at 13%, in the repeated measurement. In 5% of the patients, Cr levels were above SUL in the initial measurement and an equal 5% in the control measurement.Interpretation - Repeated WB metal ion levels did not increase in patients with bilateral ReCap-M2A-Magnum THR with a mean 1.9-year measurement interval. Long-term development of WB metal ion levels is still unclear in these patients.

Mortality and revision rate of cemented and uncemented hemiarthroplasty after hip fracture: an analysis of the Dutch Arthroplasty Register (LROI)

Background and purpose - Femoral neck fractures are commonly treated with cemented or uncemented hemiarthroplasties (HA). We evaluated differences in mortality and revision rates in this fragile patient group.Patients and methods - From January 1, 2007 until December 31, 2016, 22,356 HA procedures from the Dutch Arthroplasty Register (LROI) were included. For each HA, follow-up until death, revision, or end of follow-up (December 31, 2016) was determined. The crude revision rate was determined by competing risk analysis. Multivariable Cox regression analyses were performed to evaluate the effect of fixation method (cemented vs. uncemented) on death or revision. Age, sex, BMI, Orthopaedic Data Evaluation Panel (ODEP) rating, ASA grade, surgical approach, and previous surgery were included as potential confounders.Results - 1-year mortality rates did not differ between cemented and uncemented HA. 9-year mortality rates were 53% (95% CI 52-54) in cemented HA compared to 56% (CI 54-58) in uncemented HA. Multivariable Cox regression analysis showed similar mortality between cemented and uncemented HA (HR 1.0, CI 0.96-1.1). A statistically significantly lower 9-year revision rate of 3.1% (CI 2.7-3.6) in cemented HA compared with 5.1% (CI 4.2-6.2) in the uncemented HA was found with a lower hazard ratio for revision in cemented compared with uncemented HA (HR 0.56, CI 0.47-0.67).Interpretation - Long-term mortality rates did not differ between patients with a cemented or uncemented HA after an acute femoral neck fracture. Revision rates were lower in cemented compared with uncemented HA.

Association of early vertebroplasty with risk of hip replacement: A nationwide population-based cohort study in Taiwan

Studies show that vertebral fractures could predict the risk of hip fractures. We aimed to evaluate the potential benefits of whether the timing of vertebroplasty (VP) for vertebral fracture associated with the risk of hip fracture for hip replacement.We identified 142,782 patients from the Taiwan National Health Insurance Database with thoracolumbar vertebral fracture (International Classification of Diseases, Ninth Revision, Clinical Modification:805.2-805.9) who were followed up from 2000 to 2013. These patients were divided into those who underwent VP (VP group) (International Classification of Diseases, Ninth Revision, Clinical Modification : 78.49) within 3 months and those who did not (non-VP group). After adjusting for the confounding factors, the Cox proportional hazards analysis was used to estimate the effect of early VP on reducing the risk of hip fracture. The difference in the risk of hip replacement, between the VP group and non-VP group was estimated using the Kaplan-Meier method with the log-rank test.In the 14-year follow-up, the cumulative incidence rate of hip replacement in the VP group was lower than that in the non-VP group (0.362% and 0.533%, respectively, long-rank P < .001). There was a significant difference between the 2 groups since the first-year follow-up.Our study showed that early VP performed to avoid progression of the kyphotic changes following thoracolumbar vertebral fracture may reduce the risk of hip fracture. These results, obtained from retrospective data, indicate that a prospective study is warranted.

Effect of COVID-19 on Hip and Knee Arthroplasty Surgical Volume in the United States

BACKGROUND

In an effort to help combat the COVID-19 pandemic and preserve essential health care resources, starting in mid-March 2020, surgeons have been instructed to only perform essential surgical procedures. The vast majority of hip and knee arthroplasty surgery does not meet the definition of essential surgery. This study estimated the number of arthroplasty procedures that would be canceled because of these important restrictions.

METHODS

The US hip and knee arthroplasty procedure volume projections for 2020 were estimated from four recently published studies. Data from the American Joint Replacement Registry were utilized to determine what percentage of these cases would be considered nonessential surgery. Monthly and weekly estimates of nonessential hip and knee arthroplasty procedures that would have occurred had there not been any restrictions due to COVID-19 were calculated.

RESULTS

After excluding essential procedures, it was estimated that approximately 30,000 primary and 3000 revision hip and knee arthroplasty procedures will be canceled each week while COVID-19 restrictions regarding nonessential surgery are in place. If only 50% of nonessential cases were actually canceled across the United States, that would still result in the cancellation of 15,001 primary and 1435 revision hip and knee arthroplasty procedures per week while restrictions are in place.

CONCLUSION

This study highlights the profound impact COVID-19 is having on our current hip and knee arthroplasty volume. The large number of cases canceled because of COVID-19 translates into major financial losses for health care institutions and may have a profound impact on our patients.

Mixed ceramic combinations in primary total hip arthroplasty achieved reassuring mid-to-longterm outcomes

INTRODUCTION

Ceramic-on-ceramic couplings demonstrated to be reliable bearings in primary total hip arthroplasty (THA), with long-term remarkable results. Like-on-like configurations were widely described. On the contrary, mixed material combinations from the same manufacturer, Delta-on-Forte or Forte-on-Delta, were poorly studied. In particular, it is unknown whether mixed ceramic combinations are more at risk of ceramic fractures. Thus, a registry study was conducted to investigate the long-term survival rates and reasons for revision of mixed ceramic combinations. A comparison with Delta-on-Delta couplings was also performed.

MATERIALS AND METHODS

The regional arthroplasty registry RIPO was enquired about three cohorts of ceramic bearings (head-on-liner: Delta-on-Forte, Forte-on-Delta, Delta-on-Delta). Demographics, survival rates and reasons for revision were evaluated and compared.

RESULTS

In total, 346 (1.5%) implants had a Delta-on-Forte coupling (mean follow-up: 6.4 years). In total, 1163 (5%) THAs had a Forte-on-Delta articulation (mean follow-up: 8.2 years). Delta-on-Delta surfaces were implanted in 21,874 (93.5%) hips (mean follow-up: 3.9 years). Mixed material combinations were implanted between 2003 and 2007. The survival rates of the three cohorts were similar and were higher than 95% at 10 years. In Forte-on-Delta group, four liners failed (0.3% of the implants), whereas ceramic fractures occurred in 15 cases (0.1%) in Delta-on-Delta couplings (3 heads and 12 liners). Considering ceramic fracture as endpoint, there was no significant difference between the three survival rates.

CONCLUSIONS

Mixed ceramic bearing configurations from the same manufacturer in primary THA showed mid-to-longterm dependable outcomes, not inferior to the most recent like-on-like ceramic bearings. No additional risks of ceramic fractures were evident. Thus, closer follow-ups are not required.

Good midterm results after Birmingham hip resurfacing and total hip arthroplasty

The aim of this study is to determine the functional outcome and midterm survival rates of the Birmingham Hip Resurfacing and Birmingham Total Hip Arthroplasty. This retrospective, observational study included 150 surgeries (46 resurfacing procedures and 104 arthroplasty procedures) performed in 127 patients from 2005 to 2012. The Resurfacing and Arthroplasty study groups were evaluated with clinical (Harris Hip Score and Hip Disability and Osteoarthritis Outcome Score) and radiological follow-up. Cobalt and chromium levels were measured via blood samples. No revisions were required in either study group. Femoral stem osteolysis was observed in three patients in the Arthroplasty group. No osteolysis was observed in the Resurfacing group. Significantly higher clinical scores were observed in the Resurfacing group (p=0.04 and p=0.04, respectively). The average level of metal ions were similar in both groups. Both groups showed excellent midterm clinical and radiographic results with 100 percent survival rates. Additional follow-up is required to monitor future changes in blood metal ion levels.

Trends in the utilisation rates and acute hospital capacity needs for total hip replacements: results of an analysis of administrative data

Total hip replacement surgery is the mainstay of treatment for end-stage hip arthritis. In 2014, there were 28227 procedures (incidence rate 252/100000 population). Using administrative data, we projected the future volume of total hip replacement procedures and incidence rates using two models. The constant rate model fixes utilisation rates at 2014 levels and adjusts for demographic changes. Projections indicate 32248 admissions by 2025 or an annual growth of 1.22% (incidence rate 273). The time trend model additionally projects the evolution in age-specific utilisation rates. 34895 admissions are projected by 2025 or an annual growth of 1.95% (incidence rate 296). The projections show a shift in performing procedures at younger age. Forecasts of length of stay indicate a substantial shortening. By 2025, the required number of hospital beds will be halved. Despite more procedures, capacity can be reduced, leading to organisational change (e.g. elective orthopaedic clinics) and more labour intensive stays.

14-year hip survivorship after periacetabular osteotomy: a follow-up study on 1,385 hips

Background and purpose - Few studies have evaluated the long- and mid-term outcomes after minimally invasive periacetabular osteotomy (PAO). We investigated: (1) the long-term hip survival rate after PAO; (2) the risk of complications and additional surgery after PAO; and (3) the hip function at different follow-up points.Patients and methods - We reviewed 1,385 hips (1,126 patients) who underwent PAO between January 2004 and December 2017. Through inquiry to the Danish National Patient Registry we identified conversions to total hip arthroplasty (THA) and complications after PAO. We evaluated the Hip disability and Osteoarthritis Outcome Score (HOOS) obtained preoperatively, and at 6 months, 2-, 5-, and 10-years' follow-up.Results - 73 of the 1,385 hips were converted to THA. The overall Kaplan-Meier hip survival rate was 80% (95% CI 68-88) at 14 years with a mean follow-up of 5 years (0.03-14). 1.1% of the hips had a complication requiring surgical intervention. The most common additional surgery was removal of screws (13%) and 11% received a hip arthroscopy. At the 2-year follow-up, HOOS pain improved by a mean of 26 points (CI 24-28) and a HOOS pain score > 50 was observed in 86%.Interpretation - PAO preserved 4 of 5 hips at 14 years, with higher age leading to lower survivorship. The PAO technique was shown to be safe; 1.1% of patients had a complication that demanded surgical intervention. The majority of the patients with preserved hips have no or low pain. The operation is effective with a good clinical outcome.

Persistent Racial Disparities in Utilization Rates and Perioperative Metrics in Total Joint Arthroplasty in the U.S.: A Comprehensive Analysis of Trends from 2006 to 2015

BACKGROUND

Trends in racial disparities in total joint arthroplasty (TJA) care have been documented from 1991 to 2008. However, it remains unknown whether numerous national and orthopaedic-specific efforts to reduce these disparities have been successful. The purpose of this study was to investigate trends in racial disparities in TJA utilization and perioperative metrics between black and white patients in the U.S. from 2006 to 2015.

METHODS

The National Inpatient Sample (NIS) was queried to identify black and white patients who underwent primary total knee arthroplasty (TKA) or primary total hip arthroplasty (THA) between 2006 to 2015. Utilization rates, length of stay in the hospital (LOS), discharge disposition, and inpatient complications and mortality were trended over time. Linear and logistic regression analyses were performed to assess changes in disparities over time.

RESULTS

From 2006 to 2015, there were persistent white-black disparities in standardized utilization rates and LOS for both TKA and THA (p < 0.001 for all; ptrend > 0.05 for all). Moreover, there were worsening disparities in the rates of discharge to a facility (rather than home) after both TKA (white compared with black: 40.3% compared with 47.2% in 2006 and 25.7% compared with 34.2% in 2015, ptrend < 0.001) and THA (white compared with black: 42.6% compared with 41.7% in 2006 and 23.4% compared with 29.2% in 2015, ptrend < 0.001) and worsening disparities in complication rates after TKA (white compared with black: 5.1% compared 6.1% in 2006 and 3.9% compared with 6.0% in 2015, ptrend < 0.001).

CONCLUSIONS

There were persistent, and in many cases worsening, racial disparities in TJA utilization and perioperative care between black and white patients from 2006 to 2015 in the U.S. These results were despite national efforts to reduce racial disparities and highlight the need for continued focus on this issue. Although recent work has shown that elimination of racial disparities in TJA care is possible, the present study demonstrates that renewed efforts are still needed on a national level.

Global Perspectives on Arthroplasty of Hip and Knee Joints

There is a broad variation of implantation rates, indications, and types of prostheses used for hip and knee joint replacement procedures among different countries. The establishment of national joint registers has improved knowledge and quality of data related to joint implantation. Comparing reports of different national registries is crucial to determine potential variations in practices among surgeons and arthroplasty centers and to identify topics for future analysis. In this report, data from these registries in addition to manufacturer reports were used to evaluate procedure volumes and implants utilization trends of primary and revision total hip and knee replacement around the world.

Association Between Financial Incentives in Medicare's Hospital Readmissions Reduction Program and Hospital Readmission Performance

IMPORTANCE

The strongest evidence for the effectiveness of Medicare's Hospital Readmissions Reduction Program (HRRP) involves greater reductions in readmissions for hospitals receiving penalties compared with those not receiving penalties. However, the HRRP penalty is an imperfect measure of hospitals' marginal incentive to avoid a readmission for HRRP-targeted diagnoses.

OBJECTIVES

To assess the association between hospitals' condition-specific incentives and readmission performance and to examine the responsiveness of hospitals to condition-specific incentives compared with aggregate penalty amounts.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort analysis used Medicare readmissions data from 2823 US short-term acute care hospitals participating in HRRP to compare 3-year (fiscal years 2016-2019) follow-up readmission performance according to tertiles of hospitals' baseline (2016) marginal incentives for each of 5 HRRP-targeted conditions (acute myocardial infarction, heart failure, chronic obstructive pulmonary disease, pneumonia, and hip and/or knee surgery).

MAIN OUTCOMES AND MEASURES

Linear regression models were used to estimate mean change in follow-up readmission performance, measured using the excess readmissions ratio, with baseline condition-specific incentives and aggregate penalty amounts.

RESULTS

Of 2823 hospitals that participated in the HRRP from baseline to follow-up, 2280 (81%) had more than 1 excess readmission for 1 or more applicable condition and 543 (19%) did not have any excess readmissions. The mean (SD) financial incentive to reduce readmissions for incentivized hospitals ranged from $8762 ($3699) to $58 158 ($26 198) per 1 avoided readmission. Hospitals with greater incentives for readmission avoidance had greater decreases in readmissions compared with hospitals with smaller incentives (45% greater for pneumonia, 172% greater for acute myocardial infarction, 40% greater for hip and/or knee surgery, 32% greater for chronic obstructive pulmonary disease, and 13% greater for heart failure), whereas hospitals with no incentives had increases in excess readmissions of 4% to 7% (median, 4% [percentage change for nonincentivized hospitals was 3.7% for pneumonia, 4.2% for acute myocardial infarction, 7.1% for hip and/or knee surgery, 3.7% for chronic obstructive pulmonary disease, and 3.7% for heart failure]; P < .001). During the study period, each additional $5000 in the incentive amount was associated with a 0.6- to 1.3-percentage point decrease, or up to a 26% decrease, in excess readmissions (P < .001). Regression to the mean explained approximately one-third of the results depending on the condition examined.

CONCLUSIONS AND RELEVANCE

The findings suggest that improvements in readmission avoidance are more strongly associated with incentives from the HRRP than with aggregate penalty amounts, suggesting that the program has elicited sizeable changes. Worsened performance among hospitals with small or no incentives may indicate the need for reconsideration of the program's lack of financial rewards for high-performing hospitals.

A low-volume surgeon is an independent risk factor for leg length discrepancy after primary total hip arthroplasty: a case-control study

PURPOSE

Leg length discrepancy (LLD) is one of the bothersome complications that reduce patient satisfaction after total hip arthroplasty (THA). This study aimed to investigate the independent risk factors of LLD after primary THA.

METHODS

This is a case-control study of 163 THAs for 163 patients at our institution between April 2015 and March 2018. The relevant data about the general characteristics of the patients (age, sex, body mass index, and diagnosis), surgery (surgical approach, type of femoral stem fixation, and surgeon volume), and radiological findings (Dorr classification and pre-operative LLD) were reviewed to identify the risk factors of ≥ 5 mm post-operative LLD according to radiological measurement and to calculate odds ratios (OR) via logistic regression analysis.

RESULTS

The median (interquartile) absolute value of post-operative LLD was 3.9 (2.3-7.4) mm, and 57 (35.0%) patients had LLD of ≥ 5 mm. After controlling for possible confounders, a low-volume surgeon was considered the only independent risk factor of post-operative LLD (adjusted OR: 8.26; 95% confidence interval: 3.48, 19.60; P < 0.001). Among the 103 patients performed by high-volume surgeons, 82 (79.6%) had LLD of < 5 mm, whereas among the 60 patients performed by low-volume surgeons, only 24 (40.0%) achieved LLD of < 5 mm (P < 0.001).

CONCLUSION

A low-volume surgeon is associated with an increased risk of a post-operative LLD after primary THA, and the importance of measurements should be recognized to prevent post-operative LLD and achieve optimal outcomes. Moreover, surgeons must inform patients about the risk of developing LLD pre-operatively.

Computerized navigation for total hip arthroplasty is associated with lower complications and ninety-day readmissions: a nationwide linked analysis

INTRODUCTION

The objective was to evaluate if the use of CA-THA was associated with lower complications in the first 90 days following THA compared with conventional THA.

METHODS

The Nationwide Readmission Database (NRD) was queried to identify patients who underwent THA between 2012 and 2014. The primary outcome was arthroplasty-related complications within the first 90 days following THA. Multivariate models predicting the risk of complications, readmission, and revision-related readmission within 90 days of discharge were created.

RESULTS

A total of 309,252 patients with a minimum 90-day follow-up following elective primary THA were identified. After controlling for age, sex, comorbidities, indication, income, and type of insurance, the use of CA during THA resulted in a 12% reduced odds of 90-day complications (OR 0.88, 95% CI 0.77-0.99, p = 0.04).

DISCUSSION

The use of CA-THA resulted in lower 90-day complication rates and readmission rates compared with traditional THA after controlling for confounding variables. There was no significant difference in the rates of revision surgery between the groups within the first 90 days.

Only 8% of major preventable adverse events after hip arthroplasty are filed as claims: a Swedish multi-center cohort study on 1,998 patients

Background and purpose - Hip arthroplasty is one of the most performed surgeries in Sweden, and the rate of adverse events (AEs) is fairly high. All patients in publicly financed healthcare in Sweden are insured by the Mutual Insurance Company of Swedish County Councils (Löf). We assessed the proportion of patients that sustained a major preventable AE and filed an AE claim to Löf.Patients and methods - We performed retrospective record review using the Global Trigger Tool to identify AEs in a Swedish multi-center cohort consisting of 1,998 patients with a total or hemi hip arthroplasty. We compared the major preventable AEs with all patient-reported claims to Löf from the same cohort and calculated the proportion of filed claims.Results - We found 1,066 major preventable AEs in 744 patients. Löf received 62 claims for these AEs, resulting in a claim proportion of 8%. 58 of the 62 claims were accepted by Löf and received compensation. The claim proportion was 13% for the elective patients and 0.3% for the acute patients. The most common AE for filing a claim was periprosthetic joint infection; of the 150 infections found 37 were claimed.Interpretation - The proportion of filed claims for major preventable AEs is very low, even for obvious and serious AEs such as periprosthetic joint infection.

The evolution of robotic arm-assisted arthroplasty in Greece

BACKGROUND

The robotic arm-assisted (Mako) arthroplasty was introduced in Greece in January 2014, through the years of financial crisis. The purpose of this study is to demonstrate its evolution per procedure throughout the years.

MATERIALS AND METHODS

Data regarding type of procedure: partial knee arthroplasty (PKA), total knee arthroplasty (TKA) and total hip arthroplasty (THA) were collected from the official distributor of the Mako platform in Greece. The number of Mako arthroplasties were calculated annually and monthly per procedure type from January 2014 to December 2018.

RESULTS

A total of 1081 robotic arm-assisted arthroplasties have been performed in Greece in two private hospitals. Mako cases showed overall 163.06% increase, while THA showed 235.1% increase, during the study period. On the other hand PKA showed 61% decrease, while in during one year (2017-2018) TKA showed 402% increase.

CONCLUSIONS

Introducing robots into the orthopedic operating theater may improve precision, could lead to lower complication rates and finally may offer higher patient satisfaction scores. However, the total growth of robotic arm-assisted arthroplasties in Greece should be interpreted with caution, since all surgeries were performed in private institutions and, therefore, the economic burden of these procedures may have been withstood by specific social class patients.

The Impact Of Decision Aids On Adults Considering Hip Or Knee Surgery

Trials of decision aids developed for use in shared decision making find that patients engaged in that process tend to choose more conservative treatment for preference-sensitive conditions. Shared decision making is a collaborative process in which clinicians and patients discuss trade-offs and benefits of specific treatment options in light of patients' values and preferences. Decision aids are paper, video, or web-based tools intended to help patients match personal preferences with available treatment options. We analyzed data for 2012-15 about patients within the ten High Value Healthcare Collaborative member systems who were exposed to condition-specific decision aids in the context of consultations for hip and knee osteoarthritis, with the intention that the aids be used to support shared decision making. Compared to matched patients not exposed to the decision aids, those exposed had two-and-a-half times the odds of undergoing hip replacement surgery and nearly twice the odds of undergoing knee replacement surgery within six months of the consultation. These findings suggest that health care systems adopting decision aids developed for use in shared decision making, and used in conjunction with hip and knee osteoarthritis consultations, should not expect reduced surgical utilization.

Is the Actual Failure Rate of Hip Arthroscopy Higher Than Most Published Series? An Analysis of a Private Insurance Database

BACKGROUND

The use of hip arthroscopy (HA) for the management of intra-articular hip pathology has increased greatly, with a 600% increase in utilization from 2006-2010. Studies have demonstrated good to excellent outcomes in patients undergoing hip arthroscopy for treatment of femoroacetabular impingement (FAI) syndrome. However, some patients undergoing primary hip arthroscopy will require revision hip arthroscopy (revision HA) or conversion to total hip arthroplasty (THA). The purpose of the present study was to evaluate the association between hip arthroscopy failure and (1) osteoarthritis, (2) age > 40 years, and (3) psychiatric comorbidities.

METHODS

The Humana Inc. insurance claims database was used to identify patients undergoing hip arthroscopy between 2007 and 2015, with query by CPT (current procedural terminology code) of more than 25 million deidentified insurance and Medicare beneficiary claims. Following primary hip arthroscopy, patients were longitudinally tracked for subsequent ipsilateral hip arthroscopy (revision HA) or total hip arthroplasty (THA) with a minimum of 1-year clinical follow-up from the primary HA procedure. Hip arthroscopy failure (HA failure) was defined specifically as patients who underwent a revision HA or THA with a minimum of 1-year of clinical follow-up from the primary HA procedure. Variables assessed included presence of pre-existing osteoarthritis, age < 40 years or age > 40 years, and presence of preoperatively diagnosed psychiatric comorbidities including depression or anxiety. The relationships between revision HA, THA, or HA failure and these variables were assessed utilizing univariate and multiple logistic regression analysis. Independent predictors of revision ipsilateral hip arthroscopy and subsequent hip arthroplasty were identified using multiple logistic regression.

RESULTS

In total, 785 patients (64.1% female) underwent primary hip arthroscopy. The overall failure rate with a minimum of 1-year clinical follow-up from the index HA procedure was 18%[140/785; 8% (63/785) revision hip arthroscopy, 10% (82/785) THA]. Multivariable logistic regression analysis identified psychiatric comorbidities (Odds Ratio [OR] 2.8, 95% Confidence Interval [CI] 1.2-6.2, p<0.01) as the only independent predictor of hip arthroscopy failure (revision HA or THA). Independent predictors of revision HA included both psychiatric comorbidity (OR 2.8, 95% CI 1.2-6.2, p<0.01) and age < 40 years (OR 2.6, 95% CI 1.4-5.0, p<0.01), while age > 40 years (OR 3.09, 1.47-7.25, p<0.005), smoking (OR 2.05, 95% CI, 1.68-1.88, p=0.02), and osteoarthritis (OR 3.24, 95% CI 1.98-5.43, p<0.001) predicted conversion to THA.

CONCLUSION

The hip arthroscopy failure rate of 18% in the present study is alarmingly high, a figure much higher than reported in previously published series. Patient factors associated with conversion to THA included age > 40 years, smoking, and preexisting osteoarthritis. The presence of psychiatric comorbidities, specifically depression and anxiety, was independently associated with revision HA and overall HA failure.Level of Evidence: III.

The Usefulness of Meta-Analyses to Hip and Knee Surgeons

BACKGROUND

Comprehensive systematic reviews of results from homogenous or heterogeneous clinical trials, meta-analyses are used to summarize and to interpret studies. Proponents believe that their use can increase study power and improve precision results. Critics emphasize that heterogeneity between studies and bias of individual studies compromise the value of results. The methodology of meta-analyses has improved over time, utilizing statistical analysis to reduce bias and examining heterogeneity. With an increasing trend of meta-analyses in orthopaedic literature, this study aimed to investigate quality and clinical utility of meta-analyses for total knee arthroplasty and total hip arthroplasty.

METHODS

A systematic review of total knee arthroplasty and total hip arthroplasty meta-analyses in 3 major orthopaedic journals from January 2000 to August 2017 was performed. Three authors independently reviewed eligible meta-analyses. A quality assessment was conducted using the Oxman-Guyatt Index. Reporting quality was assessed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Two high-volume, fellowship-trained, attending surgeons specializing in total hip arthroplasty and total knee arthroplasty independently, in a blinded fashion, reviewed 24 of the highest-scored meta-analyses.

RESULTS

There were 114 studies meeting eligibility criteria, 25 published from 2000 to 2009 and 89 published from 2010 to 2017, a 3.6-fold increase. The mean Oxman-Guyatt Index score was 3.89 points, with 12 high-quality studies, 87 moderate-quality studies, and 15 low-quality studies. The mean PRISMA score for all meta-analyses was 22.2 points, with 79% classified as low to moderate. Only 23 studies listed the Level of Evidence, and 8 were Level-I studies and 9 were Level-II studies. Studies with >15 randomized controlled trials were associated with higher PRISMA and Oxman-Guyatt Index scores. In 12 articles, we were unable to decipher the types of studies included. Only 39.4% of studies showed the risk of bias. Of the 24 studies identified as high quality per the PRISMA statement, 71% were determined to be either clinically unimportant or inconclusive.

CONCLUSIONS

The number of total hip arthroplasty and total knee arthroplasty meta-analyses has markedly increased over the past decades. The majority of published meta-analyses from 3 major orthopaedic journals were not performed in accordance with established PRISMA guidelines.

CLINICAL RELEVANCE

Many published meta-analyses are low to moderate quality, and clinicians should cautiously draw conclusions from poorly executed meta-analyses.

Severe Obesity Increases Risk of Infection After Revision Total Hip Arthroplasty

BACKGROUND

The increasing prevalence of obesity has resulted in an increased number of revision total hip arthroplasties (rTHAs) performed in patients with a high body mass index (BMI). The aim of this study is to evaluate whether obesity negatively affects (1) complication rate, (2) reoperation and revision rate, and (3) patient-reported outcome in rTHA.

METHODS

In this registry-based study, we prospectively followed 444 rTHAs (cup: n = 265, stem: n = 57, both: n = 122) performed in a specialized high-volume orthopedic center between 2013 and 2015. The number of complications, and reoperation and revision surgery was registered until 5 years postoperatively. Oxford Hip Score (OHS) was evaluated preoperatively, and at 1 and 2 years postoperatively. Patients were categorized based on BMI to nonobese (<30 kg/m², n = 328), obese (30-35 kg/m², n = 82), and severe obese (≥35 kg/m², n = 34).

RESULTS

Severe obese patients, but not obese patients, had higher risks of complications and re-revision than nonobese patients. In particular, the risk of infection following rTHA was higher in severe obese patients (24%) compared to nonobese patients (3%; relative risk, 7.7). Severe obese patients had overall poorer OHS than nonobese patients, but improvement in OHS did not differ between severe obese and nonobese patients. No differences between obese and nonobese groups on OHS were observed.

CONCLUSION

In our study, severe obesity was associated with an increased risk of infection following rTHA. Patients with high BMI should be counseled appropriately before surgery.

Length of Hospital Stay for Osteoarthritic Primary Hip and Knee Replacement Surgeries in New Zealand

This study aims to explore the length of stay (LOS) of publicly funded osteoarthritic primary hip and knee replacement surgeries in New Zealand. Patients with osteoarthritis who underwent publicly funded primary hip and knee replacement surgery in 2005-2017 were included. We have identified 53,439 osteoarthritic primary hip replacements and 50,072 osteoarthritic primary knee replacements. LOS has been reduced by almost 40% over the last 13 years. Logistic regression showed that women, Māori, Pacific and Asian patients, older patients, people with more comorbidities and those having opiates on discharge and patients in earlier years were more likely to have extended LOS following hip replacements and knee replacements. Regional differences were noted in LOS between the Waitemata District Health Board (DHB) compared to Tairāwhiti DHB where patients were the most likely to have a LOS of more than 5 days after hip and knee replacements. LOS after hip and knee replacements has been reduced dramatically. Women, Māori, Pacific and Asian patients, older patients and people with more comorbidities are more likely to have extended LOS. Patients dispensed opiates on discharge had a longer LOS. There are great geographical variations in LOS for primary hip and knee surgeries in New Zealand.

Understanding the uptake of new hip replacement implants in the UK: a cohort study using data from the National Joint Registry for England and Wales

OBJECTIVES

Primary: describe uptake of new implant components (femoral stem or acetabular cup/shell) for total hip replacements (THRs) in the National Joint Registry for England and Wales (NJR). Secondary: compare the characteristics of: (a) surgeons and (b) patients who used/received new rather than established components.

DESIGN

Cohort of 618 393 primary THRs performed for osteoarthritis (±other indications) by 4979 surgeons between 2008 and 2017 in England and Wales from the NJR. We described the uptake of new (first recorded use >2008, used within 5 years) stems/cups, and variation in uptake by surgeons (primary objectives). We explored surgeon-level and patient-level factors associated with use/receipt of new components with logistic regression models (secondary objectives).

OUTCOMES

Primary outcomes: total number of new cups/stems, proportion of operations using new versus established components.

SECONDARY OUTCOMES

odds of: (a) a surgeon using a new cup/stem in a calendar-year, (b) a patient receiving a new rather than established cup/stem.

RESULTS

Sixty-eight new cups and 72 new stems were used in 47 606 primary THRs (7.7%) by 2005 surgeons (40.3%) 2008-2017. Surgeons used a median of one new stem and cup (25%-75%=1-2 both, max=10 cups, max=8 stems). Surgeons performed a median total of 22 THRs (25%-75%=5-124, range=1-3938) in the period 2008-2017. Surgeons used new stems in a median of 5.0% (25%-75%=1.3%-16.1%) and new cups in a median of 9.4% (25%-75%=2.8%-26.7%) of their THRs. Patients aged <55 years old versus those 55-80 had higher odds of receiving a new rather than established stem (OR=1.83, 95% CI=1.73-1.93) and cup (OR=1.31, 95% CI=1.25-1.37). Women had lower odds of receiving a new stem (OR=0.87, 95% CI=0.84-0.90), higher odds of receiving a new cup (OR=1.06, 95% CI=1.03-1.09).

CONCLUSIONS

Large numbers of new THR components have been introduced in the NJR since 2008. 40% of surgeons have tried new components, with wide variation in how many types and frequency they have been used.