Introduction of an order set after hip fracture improves osteoporosis medication initiation and persistence: a population-based before-after analysis.

We found that a standardized order set after hip fracture increased initiation of anti-osteoporosis medication and increased persistence at 1 year, but did not reduce secondary fractures. BACKGROUND: A treatment gap exists after osteoporosis-related fractures. Introducing standardized care can improve treatment. We evaluated the impact of a hip fracture order set (OS) on anti-osteoporosis medication (AOM) initiation, persistence, and secondary fracture prevention. METHODS: In 2015, one hospital in Manitoba, Canada, introduced a hip fracture OS including recommendations for the initiation of AOM (OS group). A control group was identified from the other hospitals in the same region. A retrospective cohort study was conducted using linked administrative health data. All individuals 50 + years with surgical treatment for low-energy hip fracture between 2010 and 2019 were included and followed for AOM initiation, medication persistence at 1 year, and secondary fractures. Between-group differences for each year were assessed using chi-square tests. Logistic regression models tested the impact of socio-demographic and clinical factors on initiation, persistence of AOM. Cox regression tested the risk of secondary fracture. RESULTS: No baseline differences between OS group (813 patients) and control group (2150 patients) were observed in demographics, socioeconomic factors, or comorbidities. An increase in post-fracture AOM initiation was seen with OS introduction (OS group year before 16.7% versus year after 48.6%, p < 0.001). No change was seen in the control group. Persistence on AOM also increased (OS group year before 17.7% versus year after 28.4%, p < 0.001). No difference in secondary fractures was observed (OS group 19.8% versus control group 18.8%, p = 0.38). CONCLUSION: Introduction of a hip fracture OS significantly increased AOM initiation and persistence at 1-year post-fracture. There was no significant difference in secondary fractures.

Unsupervised item response theory models for assessing sample heterogeneity in patient-reported outcomes measures.

PURPOSE: Unsupervised item-response theory (IRT) models such as polytomous IRT based on recursive partitioning (IRTrees) and mixture IRT (MixIRT) models can be used to assess differential item functioning (DIF) in patient-reported outcome measures (PROMs) when the covariates associated with DIF are unknown a priori. This study examines the consistency of results for IRTrees and MixIRT models. METHODS: Data were from 4478 individuals in the Alberta Provincial Project on Outcome Assessment in Coronary Heart Disease registry who received cardiac angiography in Alberta, Canada, and completed the Hospital Anxiety and Depression Scale (HADS) depression subscale items. The partial credit model (PCM) based on recursive partitioning (PCTree) and mixture PCM (MixPCM) were used to identify covariates associated with differential response patterns to HADS depression subscale items. Model covariates included demographic and clinical characteristics. RESULTS: The median (interquartile range) age was 64.5(15.7) years, and 3522(78.5%) patients were male. The PCTree identified 4 terminal nodes (subgroups) defined by smoking status, age, and body mass index. A 3-class PCM fits the data well. The MixPCM latent classes were defined by age, disease indication, smoking status, comorbid diabetes, congestive heart failure, and chronic obstructive pulmonary disease. CONCLUSION: PCTree and MixPCM were not consistent in detecting covariates associated with differential interpretations of PROM items. Future research will use computer simulations to assess these models' Type I error and statistical power for identifying covariates associated with DIF.

Patient acceptable symptom state (PASS): thresholds for the EQ-5D-5L and Oxford hip and knee scores for patients with total hip and knee replacement.

PURPOSE: To define patient acceptable symptom state (PASS) cut-off values for the EQ-5D-5L and Oxford hip (OHS) and knee (OKS) scores 6 and 12 months after total hip (THR) or knee (TKR) replacement. To compare PASS cut-off values for the EQ-5D-5L scored using: (1) the Canadian value set, (2) the crosswalk value set, and (3) the equal weighted Level Sum Score (LSS). METHODS: We mailed questionnaires to consecutive patients following surgeon referral for primary THR or TKR and at 6 and 12 months post-surgery. Patient reported outcome measures (PROMs) were the EQ-5D-5L, the OHS, and OKS. We assessed PASS cut-off values for PROMs using percentile and ROC methods, with the Youden Index. RESULTS: Five hundred forty-two surgical patients (mean age, 64 years, 57% female, 49% THR) completed baseline and 12-month questionnaires. 89% of THR and 81% of TKR patients rated PASS as acceptable at 12 months. PASS cut-off values for THR for the EQ-5D-5L (Canadian) were 0.85 (percentile) and 0.84 (Youden) at 12 months. Cut-off values were similar for the LSS (0.85 and 0.85) and lower for the crosswalk value set (0.74 and 0.73), respectively. EQ-5D-5L cut-off values for TKR were Canadian, 0.77 (Percentile) and 0.78 (Youden), LSS, 0.75 and 0.80, and crosswalk, 0.67 and 0.74, respectively. Cut-off values 6 and 12 months post-surgery ranged from 38 to 39 for the OHS, and 28 to 36 for the OKS (range 0 worst to 48 best). CONCLUSION: PASS cut-off values for the EQ-5D-5L and Oxford scores varied, not only between methods and timing of assessment, but also by different EQ-5D-5L value sets, which vary between countries. Because of this variation, PASS cut-off values are not necessarily generalizable to other populations of TJR patients. We advise caution in interpreting PROMs when using EQ-5D-5L PASS cut-off values developed in different countries. A standardization of methods is needed before published cut-off values can be used with confidence in other populations.

Outcomes and motives for not proceeding with the second stage bilateral knee replacement: a comparison of cancelled and completed bilateral total knee arthroplasty.

BACKGROUND: Staged bilateral total knee arthroplasty (TKA) is a common treatment option for patients with bilateral symptomatic knee osteoarthritis, yet some patients do not proceed with their second procedure. Our study aimed to identify the rate and reasons why patients did not proceed with their second procedure and compare their functional outcomes, satisfaction and complication rates with those of patients who had completed a staged bilateral TKA. METHODS: We determined the proportion of patients who underwent TKA but did not proceed with planned surgery for the second knee within 2 years, and compared their satisfaction with surgery, improvement in the Oxford Knee Score (OKS) and complications between groups. RESULTS: Our study included 268 patients: 220 patients who underwent staged bilateral TKA and 48 patients who cancelled their second procedure. The most common reason for not proceeding with the second procedure was a slow recovery after the first TKA (43.2%), followed by functional improvement in symptoms in the unoperated knee negating the need for surgery (27.3%), poor experience with the first surgery (22.7%), treatment of other comorbidities necessitating cancellation of their second procedure (4.6%) and employment reasons (2.3%). Patients who cancelled their second procedure were noted to have a worse postoperative OKS improvement (p < 0.001) and lower satisfaction rate (p < 0.001), than patients who underwent staged bilateral TKA. CONCLUSION: About one-fifth of patients scheduled for staged bilateral TKA declined to proceed with the second knee surgery within 2 years showing a substantially decreased functional outcome and satisfaction rate. However, more than one-quarter (27.3%) of patients noted improvements in their contralateral (unoperated) knee, such that a second surgery was no longer felt to be necessary.

Quality indicators in primary elective total hip and knee arthroplasty.

PURPOSE: Total hip arthroplasty (THA) and total knee arthroplasty (TKA) represent a significant portion of healthcare spending and are high-priority for quality improvement initiatives. This study aims to develop quality indicators (QIs) in the care of primary elective THA and TKA patients. These QIs serve a number of purposes including documentation of the quality of care, objective comparisons of institutions/providers, facilitating pay-for-performance initiatives, and supporting accountability, regulation, and accreditation. METHODS: A guideline-based approach, initially described by Kötter et al., was utilized. Eight clinical practice guidelines (CPGs) were evaluated for candidate indicators (CIs). CIs with high-quality evidence and consensus statements were extracted. Eighteen additional CIs were included from previous work that evaluated quality improvement databases. Each CI and supporting evidence was submitted for independent review by an expert panel. The RAND Corporation-University of California, Los Angeles (RAND/UCLA) appropriateness methodology was utilized and items were rated based on validity, reliability, and feasibility of measurement. After two rounds of ratings and ranking, a final ranked list of QIs was obtained. RESULTS: Fifty-six CIs were identified from the literature and CPGs or proposed by the expert panel. Two rounds of voting resulted in 12 total QIs that were deemed appropriate measures of high-quality care. The final 12 QIs were ranked by order of importance: use of peri-operative tranexamic acid, infusion of prophylactic antibiotics prior to inflation of tourniquet, appropriate post-operative venous thromboembolic prophylaxis, complication rate, rate of secondary procedure, readmission rate, early mobilization, average change of pre- to one year post-operative functional status, use of multimodal analgesia, use of neuraxial anesthesia, use of peri-articular injection in TKA, and use of pre-operative PO analgesia. CONCLUSION: This study is an expert opinion based on parameters observed in modern and high-quality academic settings. Twelve QIs are proposed to assess the quality of care in the peri-operative management of primary elective THA and TKA patients.

A comparison of methods to address item non-response when testing for differential item functioning in multidimensional patient-reported outcome measures.

PURPOSE: Item non-response (i.e., missing data) may mask the detection of differential item functioning (DIF) in patient-reported outcome measures or result in biased DIF estimates. Non-response can be challenging to address in ordinal data. We investigated an unsupervised machine-learning method for ordinal item-level imputation and compared it with commonly-used item non-response methods when testing for DIF. METHODS: Computer simulation and real-world data were used to assess several item non-response methods using the item response theory likelihood ratio test for DIF. The methods included: (a) list-wise deletion (LD), (b) half-mean imputation (HMI), (c) full information maximum likelihood (FIML), and (d) non-negative matrix factorization (NNMF), which adopts a machine-learning approach to impute missing values. Control of Type I error rates were evaluated using a liberal robustness criterion for α = 0.05 (i.e., 0.025-0.075). Statistical power was assessed with and without adoption of an item non-response method; differences > 10% were considered substantial. RESULTS: Type I error rates for detecting DIF using LD, FIML and NNMF methods were controlled within the bounds of the robustness criterion for > 95% of simulation conditions, although the NNMF occasionally resulted in inflated rates. The HMI method always resulted in inflated error rates with 50% missing data. Differences in power to detect moderate DIF effects for LD, FIML and NNMF methods were substantial with 50% missing data and otherwise insubstantial. CONCLUSION: The NNMF method demonstrated comparable performance to commonly-used non-response methods. This computationally-efficient method represents a promising approach to address item-level non-response when testing for DIF.

How do Patient-reported Outcome Scores in International Hip and Knee Arthroplasty Registries Compare?

BACKGROUND: Patient-reported outcome measures (PROMs) are the only systematic approach through which the patient's perspective can be considered by surgeons (in determining a procedure's efficacy or appropriateness) or healthcare systems (in the context of value-based healthcare). PROMs in registries enable international comparison of patient-centered outcomes after total joint arthroplasty, but the extent to which those scores may vary between different registry populations has not been clearly defined. QUESTIONS/PURPOSES: (1) To what degree do mean change in general and joint-specific PROM scores vary across arthroplasty registries, and to what degree is the proportion of missing PROM scores in an individual registry associated with differences in the mean reported change scores? (2) Do PROM scores vary with patient BMI across registries? (3) Are comorbidity levels comparable across registries, and are they associated with differences in PROM scores? METHODS: Thirteen national, regional, or institutional registries from nine countries reported aggregate PROM scores for patients who had completed PROMs preoperatively and 6 and/or 12 months postoperatively. The requested aggregate PROM scores were the EuroQol-5 Dimension Questionnaire (EQ-5D) index values, on which score 1 reflects "full health" and 0 reflects "as bad as death." Joint-specific PROMs were the Oxford Knee Score (OKS) and the Oxford Hip Score (OHS), with total scores ranging from 0 to 48 (worst-best), and the Hip Disability and Osteoarthritis Outcome Score-Physical Function shortform (HOOS-PS) and the Knee Injury and Osteoarthritis Outcome Score-Physical Function shortform (KOOS-PS) values, scored 0 to 100 (worst-best). Eligible patients underwent primary unilateral THA or TKA for osteoarthritis between 2016 and 2019. Registries were asked to exclude patients with subsequent revisions within their PROM collection period. Raw aggregated PROM scores and scores adjusted for age, gender, and baseline values were inspected descriptively. Across all registries and PROMs, the reported percentage of missing PROM data varied from 9% (119 of 1354) to 97% (5305 of 5445). We therefore graphically explored whether PROM scores were associated with the level of data completeness. For each PROM cohort, chi-square tests were performed for BMI distributions across registries and 12 predefined PROM strata (men versus women; age 20 to 64 years, 65 to 74 years, and older than 75 years; and high or low preoperative PROM scores). Comorbidity distributions were evaluated descriptively by comparing proportions with American Society of Anesthesiologists (ASA) physical status classification of 3 or higher across registries for each PROM cohort. RESULTS: The mean improvement in EQ-5D index values (10 registries) ranged from 0.16 to 0.33 for hip registries and 0.12 to 0.25 for knee registries. The mean improvement in the OHS (seven registries) ranged from 18 to 24, and for the HOOS-PS (three registries) it ranged from 29 to 35. The mean improvement in the OKS (six registries) ranged from 15 to 20, and for the KOOS-PS (four registries) it ranged from 19 to 23. For all PROMs, variation was smaller when adjusting the scores for differences in age, gender, and baseline values. After we compared the registries, there did not seem to be any association between the level of missing PROM data and the mean change in PROM scores. The proportions of patients with BMI 30 kg/m 2 or higher ranged from 16% to 43% (11 hip registries) and from 35% to 62% (10 knee registries). Distributions of patients across six BMI categories differed across hip and knee registries. Further, for all PROMs, distributions also differed across 12 predefined PROM strata. For the EQ-5D, patients in the younger age groups (20 to 64 years and 65 to 74 years) had higher proportions of BMI measurements greater than 30 kg/m 2 than older patients, and patients with the lowest baseline scores had higher proportions of BMI measurements more than 30 kg/m 2 compared with patients with higher baseline scores. These associations were similar for the OHS and OKS cohorts. The proportions of patients with ASA Class at least 3 ranged across registries from 6% to 35% (eight hip registries) and from 9% to 42% (nine knee registries). CONCLUSION: Improvements in PROM scores varied among international registries, which may be partially explained by differences in age, gender, and preoperative scores. Higher BMI tended to be associated with lower preoperative PROM scores across registries. Large variation in BMI and comorbidity distributions across registries suggest that future international studies should consider the effect of adjusting for these factors. Although we were not able to evaluate its effect specifically, missing PROM data is a recurring challenge for registries. Demonstrating generalizability of results and evaluating the degree of response bias is crucial in using registry-based PROMs data to evaluate differences in outcome. Comparability between registries in terms of specific PROMs collection, postoperative timepoints, and demographic factors to enable confounder adjustment is necessary to use comparison between registries to inform and improve arthroplasty care internationally. LEVEL OF EVIDENCE: Level III, therapeutic study.

Modes of failure of hip hemiarthroplasty for femoral neck fracture.

BACKGROUND: Hemiarthroplasty is a common treatment for displaced femoral neck fractures, but limited Canadian data are available about hemiarthroplasty failure. We evaluated the frequency and predictors of hemiarthroplasty failure in Manitoba. METHODS: In this retrospective multicentre province-wide study, billing and joint registry databases showed 4693 patients who had hemiarthroplasty for treatment of femoral neck fracture in Manitoba over an 11-year period (2005-2015), including 155 hips with subsequent reoperations (open or closed) for treatment of hemiarthroplasty failure. Hospital records were reviewed to identify modes of hemiarthroplasty failure, comorbidities and reoperations. Data were analyzed using χ2 test and Poisson and γ regression models. RESULTS: During our study period, 155 hips (154 patients [3%]) underwent 230 reoperations. Of these, 131 hips (85%) initially had an uncemented unipolar modular implant. Indications for first-time reoperation included periprosthetic femur fracture (49 hips [32%]), dislocation (45 hips [29%]), acetabular wear (28 hips [18%]) and infection (26 hips [17%]). There were 46 hips (30%) that had 2 or more reoperations. Reoperation for dislocation was associated with presence of dementia; acetabular wear was associated with absence of dementia. Time from hemiarthroplasty to reoperation was associated inversely with age at hemiarthroplasty, dislocation and dementia and was directly associated with acetabular wear. The risk of having 2 or more reoperations was associated independently with dislocation, infection, and alcohol abuse. CONCLUSION: Hemiarthroplasty for femoral neck fracture in Manitoba had a low frequency of failure. Risk factors for multiple reoperations included dislocation, infection and alcohol abuse.

Aspirin or Rivaroxaban for VTE Prophylaxis after Hip or Knee Arthroplasty.

BACKGROUND: Clinical trials and meta-analyses have suggested that aspirin may be effective for the prevention of venous thromboembolism (proximal deep-vein thrombosis or pulmonary embolism) after total hip or total knee arthroplasty, but comparisons with direct oral anticoagulants are lacking for prophylaxis beyond hospital discharge. METHODS: We performed a multicenter, double-blind, randomized, controlled trial involving patients who were undergoing total hip or knee arthroplasty. All the patients received once-daily oral rivaroxaban (10 mg) until postoperative day 5 and then were randomly assigned to continue rivaroxaban or switch to aspirin (81 mg daily) for an additional 9 days after total knee arthroplasty or for 30 days after total hip arthroplasty. Patients were followed for 90 days for symptomatic venous thromboembolism (the primary effectiveness outcome) and bleeding complications, including major or clinically relevant nonmajor bleeding (the primary safety outcome). RESULTS: A total of 3424 patients (1804 undergoing total hip arthroplasty and 1620 undergoing total knee arthroplasty) were enrolled in the trial. Venous thromboembolism occurred in 11 of 1707 patients (0.64%) in the aspirin group and in 12 of 1717 patients (0.70%) in the rivaroxaban group (difference, 0.06 percentage points; 95% confidence interval [CI], -0.55 to 0.66; P<0.001 for noninferiority and P=0.84 for superiority). Major bleeding complications occurred in 8 patients (0.47%) in the aspirin group and in 5 (0.29%) in the rivaroxaban group (difference, 0.18 percentage points; 95% CI, -0.65 to 0.29; P=0.42). Clinically important bleeding occurred in 22 patients (1.29%) in the aspirin group and in 17 (0.99%) in the rivaroxaban group (difference, 0.30 percentage points; 95% CI, -1.07 to 0.47; P=0.43). CONCLUSIONS: Among patients who received 5 days of rivaroxaban prophylaxis after total hip or total knee arthroplasty, extended prophylaxis with aspirin was not significantly different from rivaroxaban in the prevention of symptomatic venous thromboembolism. (Funded by the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT01720108 .).

Variation in prophylactic tranexamic acid administration among anesthesiologists and surgeons in orthopedic surgery: a retrospective cohort study.

PURPOSE: Tranexamic acid (TXA) reduces red blood cell transfusion in various orthopedic surgeries, yet the degree of practice variation in its use among anesthesiologists and surgeons has not been described. To target future knowledge transfer and implementation strategies, and to better understand determinants of variability in prophylactic TXA use, our primary objective was to evaluate the influence of surgical team members on the variability of prophylactic TXA administration. METHODS: This was a retrospective cohort study of all adult patients undergoing primary total hip arthroplasty (THA), hip fracture surgery, and spine fusion ± vertebrectomy at two Canadian hospitals between January 2014 and December 2016. We used Canadian Classification of Health Interventions procedure codes within the Discharge Abstract Database which we linked to the Ottawa Data Warehouse. We described the percentage of patients that received TXA by individual surgery, the specifics of TXA dosing, and estimated the effect of anesthesiologists and surgeons on prophylactic TXA using multivariable mixed-effects logistic regression analyses. RESULTS: In the 3,900 patients studied, TXA was most commonly used in primary THA (85%; n = 1,344/1,582), with lower use in hip fracture (23%; n = 342/1,506) and spine fusion surgery (23%; n = 186/812). The median [interquartile range] total TXA dose was 1,000 [1,000-1,000] mg, given as a bolus in 92% of cases. Anesthesiologists and surgeons added significant variability to the odds of receiving TXA in hip fracture surgery and spine fusion, but not primary THA. Most of the variability in TXA use was attributed to patient and other factors. CONCLUSION: We confirmed the routine use of TXA in primary THA, while observing lower utilization with more variability in hip fracture and spine fusion surgery. Further study is warranted to understand variations in use and the barriers to TXA implementation in a broader population of orthopedic surgical patients at high risk for transfusion.

RéSUMé: OBJECTIF: L'acide tranexamique (ATX) réduit la transfusion d'érythrocytes dans diverses chirurgies orthopédiques. Cependant, les variations de pratique quant à son utilisation parmi les anesthésiologistes et les chirurgiens n'ont pas été décrites. Afin de cibler les stratégies futures de transfert des connaissances et de mise en œuvre, et pour mieux comprendre les déterminants de la variabilité dans l'utilisation prophylactique d'ATX, notre objectif principal était d'évaluer l'influence des membres de l'équipe chirurgicale sur la variabilité de l'administration prophylactique d'ATX. MéTHODE: Il s'agissait d'une étude de cohorte rétrospective de tous les patients adultes subissant une arthroplastie totale primaire de la hanche (ATH), une chirurgie de fracture de la hanche et une fusion intervertébrale ± vertébrectomie dans deux hôpitaux canadiens entre janvier 2014 et décembre 2016. Nous avons utilisé les codes de procédure de la Classification canadienne des interventions en santé dans la Base de données sur les congés des patients, que nous avons liée à la banque de données d'Ottawa. Nous avons décrit le pourcentage de patients qui ont reçu de l'ATX par chirurgie individuelle, les détails du dosage de l'ATX, et avons estimé l'effet des anesthésiologistes et des chirurgiens sur l'ATX prophylactique en réalisant des analyses de régression logistique multivariées à effets mixtes. RéSULTATS: Parmi les 3900 patients étudiés, l'ATX était le plus fréquemment utilisé lors d'une ATH primaire (85 %; n = 1344/1582), avec une utilisation plus faible lors de chirurgie de fracture de la hanche (23 %; n = 342/1506) et de chirurgie de fusion intervertébrale (23 %; n = 186/812). La dose totale médiane [écart interquartile] d'ATX était de 1000 mg [1000 à 1000], administrés dans 92 % des cas sous forme de bolus. Les anesthésiologistes et les chirurgiens ont ajouté une variabilité significative aux probabilités de recevoir de l'ATX lors d'une chirurgie de fracture de la hanche et de fusion, mais pas lors d'ATH primaire. La majeure partie de la variabilité dans l'utilisation d'ATX était attribuable aux facteurs liés au patient et à d'autres facteurs. CONCLUSION: Nous avons confirmé l'utilisation de routine de l'ATX dans l'ATH primaire, tout en observant une utilisation moins répandue et plus variable lors de chirurgie de fracture de la hanche et de fusion intervertébrale. Une étude plus approfondie est nécessaire pour comprendre les variations d'utilisation et les obstacles à la mise en œuvre de l'ATX dans une population plus étendue de patients de chirurgie orthopédique à haut risque de transfusion.

Collection and Reporting of Patient-reported Outcome Measures in Arthroplasty Registries: Multinational Survey and Recommendations.

BACKGROUND: Patient-reported outcome measures (PROMs) are validated questionnaires that are completed by patients. Arthroplasty registries vary in PROM collection and use. Current information about registry collection and use of PROMs is important to help improve methods of PROM data analysis, reporting, comparison, and use toward improving clinical practice. QUESTIONS/PURPOSES: To characterize PROM collection and use by registries, we asked: (1) What is the current practice of PROM collection by arthroplasty registries that are current or former members of the International Society of Arthroplasty Registries, and are there sufficient similarities in PROM collection between registries to enable useful international comparisons that could inform the improvement of arthroplasty care? (2) How do registries differ in PROM administration and demographic, clinical, and comorbidity index variables collected for case-mix adjustment in data analysis and reporting? (3) What quality assurance methods are used for PROMs, and how are PROM results reported and used by registries? (4) What recommendations to arthroplasty registries may improve PROM reporting and facilitate international comparisons? METHODS: An electronic survey was developed with questions about registry structure and collection, analysis, reporting, and use of PROM data and distributed to directors or senior administrators of 39 arthroplasty registries that were current or former members of the International Society of Arthroplasty Registries. In all, 64% (25 of 39) of registries responded and completed the survey. Missing responses from incomplete surveys were captured by contacting the registries, and up to three reminder emails were sent to nonresponding registries. Recommendations about PROM collection were drafted, revised, and approved by the International Society of Arthroplasty Registries PROMs Working Group members. RESULTS: Of the 25 registries that completed the survey, 15 collected generic PROMs, most frequently the EuroQol-5 Dimension survey; 16 collected joint-specific PROMs, most frequently the Knee Injury and Osteoarthritis Outcome Score and Hip Disability and Osteoarthritis Outcome Score; and 11 registries collected a satisfaction item. Most registries administered PROM questionnaires within 3 months before and 1 year after surgery. All 16 registries that collected PROM data collected patient age, sex or gender, BMI, indication for the primary arthroplasty, reason for revision arthroplasty, and a comorbidity index, most often the American Society of Anesthesiologists classification. All 16 registries performed regular auditing and reporting of data quality, and most registries reported PROM results to hospitals and linked PROM data to other data sets such as hospital, medication, billing, and emergency care databases. Recommendations for transparent reporting of PROMs were grouped into four categories: demographic and clinical, survey administration, data analysis, and results. CONCLUSION: Although registries differed in PROM collection and use, there were sufficient similarities that may enable useful data comparisons. The International Society of Arthroplasty Registries PROMs Working Group recommendations identify issues that may be important to most registries such as the need to make decisions about survey times and collection methods, as well as how to select generic and joint-specific surveys, handle missing data and attrition, report data, and ensure representativeness of the sample. CLINICAL RELEVANCE: By collecting PROMs, registries can provide patient-centered data to surgeons, hospitals, and national entities to improve arthroplasty care.

Prospective randomized trial of continuous femoral nerve block with posterior capsular injection versus periarticular injection for analgesia in primary total knee arthroplasty.

Background: Femoral nerve block (NB) and periarticular injection (PI) are 2 common options for pain control after total knee arthroplasty (TKA). We performed a prospective triple-blinded randomized trial comparing continuous femoral NB to PI, with follow-up to 1 year. Methods: Patients younger than 70 years of age who were scheduled to undergo elective primary TKA under spinal anesthesia between 2009 and 2010 were randomly allocated to receive either continuous femoral NB or PI. Patients in the NB group received ropivacaine through an NB catheter and a sham saline PI. The PI group received a PI of ropivacaine, morphine, ketorolac and epinephrine, and a sham saline infusion via an NB catheter. Both groups had standardized oral analgesia preoperatively, spinal anesthesia and sedation, and postoperative analgesia. Surgeons, anesthesiologists, patients and assessors were blinded to group assignment. Pain was measured twice daily on postoperative days 1 and 2, at rest and with motion, with a numeric rating scale. Patient satisfaction, pain (Oxford Knee Score) and range of motion were assessed at 1 year. Results: There were 39 participants in the NB group and 35 participants in the PI group. There were no statistically significant differences between the groups at baseline. Statistically but nonclinically significant reductions in pain scores on postoperative day 2 and in narcotic need on the day of surgery were found in the PI group. Patient-reported satisfaction did not differ at any time point. At 1 year, knee flexion was significantly greater in the NB group than in the PI group (mean range of motion 120° v. 110°, p = 0.03). Conclusion: There was no demonstrated improvement in pain control with the use of an NB versus PI when used with multimodal analgesia. Clinicians should opt for the modality that has the best efficiency for their surgical environment. ClinicalTrials.gov # NCT00869037

Contexte: Le bloc nerveux (BN) fémoral et l'infiltration périarticulaire (IP) sont 2 options d'usage courant pour maîtriser la douleur après l'arthroplastie totale du genou (ATG). Nous avons procédé à un essai prospectif randomisé à triple insu afin de comparer le BN fémoral et l'IP, avec un suivi allant jusqu'à 1 an. Méthodes: Les patients de moins de 70 ans qui devaient subir une ATG élective sous épidurale entre 2009 et 2010 ont été assignés aléatoirement à un BN fémoral continu ou à une IP. Les patients du groupe soumis au BN recevaient de la ropivacaïne par un cathéter de BN et une IF simulée (solution saline). Le groupe soumis à l'IP recevait de la ropivacaïne, de la morphine, du kétorolac et de l'épinéphrine et une perfusion simulée (solution saline) par un cathéter de BN. Les 2 groupes avaient reçu une analgésie orale standard avant l'intervention, une anesthésie rachidienne avec sédatifs et une analgésie postopératoire. Les chirurgiens, les anesthésiologistes, les patients et les évaluateurs ne connaissaient pas l'assignation des agents aux différents groupes. La douleur a été mesurée 2 fois par jour aux jours 1 et 2 postopératoires, au repos et à la mobilisation, au moyen d'une échelle numérique. La satisfaction des patients, la douleur (questionnaire d'Oxford pour le genou) et l'amplitude de mouvement ont toutes été évaluées après 1 an. Résultats: Le groupe soumis au BN comptait 39 participants et le groupe soumis à l'IP en comptait 35. Il n'y avait aucune différence statistiquement significative entre les groupes au départ. Des réductions statistiquement (et non cliniquement) significatives des scores de douleur au deuxième jour postopératoire et du recours aux narcotiques le jour de la chirurgie ont été notées dans le groupe soumis à l'IP. La satisfaction autodéclarée des patients n'a différé à aucun moment. Au bout de 1 an, la flexion du genou était significativement plus marquée dans le groupe soumis au BN que dans le groupe soumis à l'IP (amplitude de mouvement moyenne 120° c. 110°, p = 0,03) Conclusion: On n'a démontré aucune amélioration de la maîtrise de la douleur avec l'utilisation du BN c. IP avec analgésie multimodale. Les médecins devraient opter pour la modalité qui offre le meilleur degré d'efficience en fonction de leur environnement chirurgical. ClinicalTrials.gov # NCT00869037

Patient expectations and satisfaction 6 and 12 months following total hip and knee replacement.

PURPOSE: To assess (1) patient expectations before total hip (THR) and knee (TKR) replacement; (2) which expectations are met and unmet 6 and 12 months post-surgery; (3) the role of unmet expectations in satisfaction. METHODS: Questionnaires were mailed to consecutive patients following surgeon referral for primary THR or TKR. Patients listed their own expectations and also completed the Hospital for Special Surgery (HSS) Expectation Survey. We used content analysis to group expectations into themes. At 6 and 12 months post-surgery, patients were given a copy of their own list of individual expectations and reassessed each one as met or unmet. We also assessed fulfilled HSS expectations and satisfaction with surgery. RESULTS: The sample of 556 patients (49% THR, 57% female) had a mean age of 64 years (SD10). The five most frequent expectation themes were pain relief, mobility, walking, physical activities, and daily activities. Of these, physical activities had the lowest percentage met 12 months post-surgery. 95% (THR) and 87% (TKR) were satisfied/very satisfied with their surgery 12 months post-surgery. Very satisfied patients had a significantly greater percentage of met expectations (96% THR; 92% TKR) than dissatisfied patients (42% THR; 12% TKR). Although most expectations listed by patients were included in the HSS surveys, some were not, particularly for TKR. From 6 to 12 months, there was a significant increase in patient satisfaction for self-care, daily activities, and met expectations for THR and pain relief, self-care, daily activities, and recreational activities for TKR. CONCLUSIONS: Expectations should be explicitly addressed before surgery, including a discussion of realistic expectations, particularly for physical activities.

Short-term Revision Risk of Patellofemoral Arthroplasty Is High: An Analysis from Eight Large Arthroplasty Registries.

BACKGROUND: Patellofemoral arthroplasty (PFA) is one option for the treatment of isolated patellofemoral osteoarthritis, but there are limited data regarding the procedure and results. Because isolated patellofemoral arthritis is relatively uncommon, available case series generally are small, and even within national registries, sample sizes are limited. Combining data from multiple registries may aid in assessing worldwide PFA usage and survivorship. QUESTIONS/PURPOSES: We combined and compared data from multiple large arthroplasty registries worldwide to ask: (1) What proportion of patients undergoing primary knee arthroplasty have PFA? (2) What are the patient and prosthesis characteristics associated with PFA in common practice, as reflected in registries? (3) What is the survivorship free from revision of PFA and what are the reasons for and types of revisions? METHODS: Data were provided by eight registries that are members of the International Society of Arthroplasty Registries (ISAR) who agreed to share aggregate data: Australia, New Zealand, Canada, Sweden, Finland, Norway, the Netherlands, and the United States. De-identified data were obtained for PFA performed from either the beginning of year 2000, or the earliest recorded implantation date after that in each individual registry when PFA data collection commenced, up to December 31, 2016. This included patient demographics, implant use, all-cause revision rate (determined by cumulative percent revision [CPR]), and reasons for and type of revision. RESULTS: During the data collection period, 6784 PFAs were performed in the eight countries. PFAs comprised less than 1% of primary knee replacements in all registries. Patient demographics were comparable in all countries. Patients were generally more likely to be women than men, and the mean age ranged from 50 years to 60 years. All registries showed a high rate of revision for PFA. The 5-year CPR for any reason ranged from 8.0% (95% CI 4.5 to 11.5) in Norway to 18.1% (95% CI 15.5 to 20.7) in the Netherlands. The most common reason for revision across all countries was disease progression (42%, 434 of 1034). Most PFAs (83%, 810 of 980) were revised to a TKA. CONCLUSIONS: The revision risk of PFA in all registries surveyed was more than three times higher than the reported revision risk of TKA at the same times. The survivorship of PFA is similar to that of the no-longer-used procedure of metal-on-metal conventional hip replacement. Although there may be potential functional benefits from PFA, these findings of consistent and alarmingly high rates of revision should create concern, particularly as this procedure is often used in younger patients. LEVEL OF EVIDENCE: Level III, therapeutic study.

Examination of total hip and knee arthroplasty tissues.

BACKGROUND: Many practices require tissues from hip and knee arthroplasty procedures to be sent for pathologic examination. These examinations rarely provide information beyond the clinical or radiologic diagnosis and rarely alter clinical management. We aimed to determine the rate at which histologic diagnoses based on gross assessment alone or gross plus microscopic assessment correspond with reported clinical diagnoses in patients undergoing total joint arthroplasties and whether the histologic diagnoses alter patient management. METHODS: We retrospectively reviewed arthroplasty cases performed at a high-volume teaching hospital in Manitoba, Canada. The clinical diagnosis was compared with the final pathology report based on gross examination, with or without histologic assessment. The results of the comparison were classified into 3 categories: concordant (same diagnosis), discrepant (different diagnoses without alterations in management) and discordant (different diagnoses resulting in management change). The overall provincial cost for pathologic examination was determined by multiplying the total examination cost by the estimated number of arthroplasty cases. RESULTS: There were 773 patients in our study sample. The concordant rate was 98.3% (95% confidence interval [CI] 97.1%-99.1%), the discrepant rate was 1.7% (95% CI 0.9%-2.9%) and the discordant rate was 0.0% (95% CI 0%-0.5%) for 773 cases. The pathology diagnosis did not alter patient management in any case. A total of 91.5% of specimens did not require full histologic review and received gross descriptions only. The discrepancy rate was higher in cases that included microscopic examination than in those that received only gross descriptions (15.2% v. 0.4%, p < 0.001). The overall provincial cost for pathologic examination was estimated at Can$304 556. CONCLUSION: Submitting routine tissue from arthroplasty procedures to pathology does not affect patient management and therefore provides no value for the health care resources expended in doing so.

CONTEXTE: Beaucoup d'établissements exigent que des tissus soient envoyés pour un examen anatomopathologique après une arthroplastie de la hanche et du genou. Ces examens n'apportent généralement pas d'information nouvelle quant au diagnostic clinique ou radiologique et modifient rarement la prise en charge. Notre objectif était de déterminer le pourcentage de correspondance entre les diagnostics histologiques fondés sur l'inspection grossière uniquement ou sur l'inspection grossière et l'examen au microscope, et les diagnostics cliniques des patients qui subissent des arthroplasties totales. Nous cherchions également à savoir si les diagnostics histologiques modifient la prise en charge. MÉTHODES: Nous avons procédé à une analyse rétrospective d'arthroplasties effectuées dans un grand hôpital universitaire du Manitoba, au Canada. Le diagnostic clinique était comparé au rapport final de pathologie fondé sur une inspection grossière, avec ou sans examen histologique. Les résultats de cette comparaison étaient classés en 3 catégories : concordance (même diagnostic), divergence (diagnostics différents, sans modification de la prise en charge) et discordance (diagnostics différents entraînant une modification de la prise en charge). Le coût global pour la province associé aux examens pathologiques a été établi en multipliant le coût total d'un examen par le nombre estimé de cas d'arthroplastie. RÉSULTATS: Notre échantillon comprenait 773 patients. Le taux de concordance était de 98,3 % (intervalle de confiance [IC] de 95 % 97,1 %­99,1 %), le taux de divergence était de 1,7 % (IC de 95 % 0,9 %­2,9 %) et le taux de discordance de 0,0 % (IC de 95 % 0 %­0,5 %). Dans tous les cas, le diagnostic pathologique n'a pas modifié la prise en charge. Au total, 91,5 % des spécimens ne nécessitaient pas d'examen histologique complet et n'ont fait l'objet que d'une inspection grossière. Le pourcentage d'anomalie était plus élevé pour les spécimens analysés au microscope que pour ceux ayant uniquement subi une inspection grossière (15,2 % c. 0,4 %, p < 0,001). Le coût total des examens pathologiques pour la province a été estimé à 304 556 $ CA. CONCLUSION: L'analyse pathologique systématique de tissus prélevés lors d'arthroplasties n'entraîne pas une modification de la prise en charge du patient; il n'y a donc pas de valeur associée aux ressources de santé utilisées pour ces examens.

Impact of missing data on bias and precision when estimating change in patient-reported outcomes from a clinical registry.

BACKGROUND: Clinical registries, which capture information about the health and healthcare use of patients with a health condition or treatment, often contain patient-reported outcomes (PROs) that provide insights about the patient's perspectives on their health. Missing data can affect the value of PRO data for healthcare decision-making. We compared the precision and bias of several missing data methods when estimating longitudinal change in PRO scores. METHODS: This research conducted analyses of clinical registry data and simulated data. Registry data were from a population-based regional joint replacement registry for Manitoba, Canada; the study cohort consisted of 5631 patients having total knee arthroplasty between 2009 and 2015. PROs were measured using the 12-item Short Form Survey, version 2 (SF-12v2) at pre- and post-operative occasions. The simulation cohort was a subset of 3000 patients from the study cohort with complete PRO information at both pre- and post-operative occasions. Linear mixed-effects models based on complete case analysis (CCA), maximum likelihood (ML) and multiple imputation (MI) without and with an auxiliary variable (MI-Aux) were used to estimate longitudinal change in PRO scores. In the simulated data, bias, root mean squared error (RMSE), and 95% confidence interval (CI) coverage and width were estimated under varying amounts and types of missing data. RESULTS: Three thousand two hundred thirty (57.4%) patients in the study cohort had complete data on the SF-12v2 at both occasions. In this cohort, mixed-effects models based on CCA resulted in substantially wider 95% CIs than models based on ML and MI methods. The latter two methods produced similar estimates and 95% CI widths. In the simulation cohort, when 50% of the data were missing, the MI-Aux method, in which a single hypothetical auxiliary variable was strongly correlated (i.e., 0.8) with the outcome, reduced the 95% CI width by up to 14% and bias and RMSE by up to 50 and 45%, respectively, when compared with the MI method. CONCLUSIONS: Missing data can substantially affect the precision of estimated change in PRO scores from clinical registry data. Inclusion of auxiliary information in MI models can increase precision and reduce bias, but identifying the optimal auxiliary variable(s) may be challenging.

Differential item functioning of the SF-12 in a population-based regional joint replacement registry.

BACKGROUND: Joint replacement, an increasingly common procedure amongst older adults, can substantially improve health-related quality of life (HRQoL). However, differential item functioning (DIF) may affect the accurate interpretation of differences in HRQoL amongst patients with different demographic and health status characteristics but the same underlying (i.e., latent) level of the investigated construct. This study tested for DIF in pre-operative SF-12 physical health (PH) and mental health (MH) sub-scale items amongst patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: Data were from a population-based joint replacement registry from the Canadian province of Manitoba. TKA and THA patients who had surgery between 2009 and 2015 and completed a pre-operative assessment were included. DIF was tested using the multiple indicators multiple causes (MIMIC) method with sex, age group, body weight status, and presence of multiple comorbid conditions (i.e., multimorbidity) as covariates. Analyses were stratified by joint type. RESULTS: The study cohort included 8820 patients; 42.1% underwent THA, 57.3% were female, 32.7% were 70+ years, and 52.8% were obese. For each sub-scale, four of the six items exhibited DIF in both THA and TKA groups. Differences in the covariate effect estimates for DIF and No-DIF models on the MH latent variable were largest for age and body weight status for the THA group, and for sex and multimorbidity for the TKA group. All of the differences were small for PH. Multimorbidity had the strongest association with PH and age and sex had the strongest association with MH in the DIF models. CONCLUSIONS: Demographic and health status characteristics influenced SF-12 PH and MH item responses in joint replacement populations, although the size of the effects were not large for PH. We recommend testing and adjusting for DIF effects to ensure comparability of HRQoL measures in joint replacement populations.

A double-blind randomized controlled trial of total knee replacement using patient-specific cutting block instrumentation versus standard instrumentation

Background: Patient-specific cutting blocks in total knee arthroplasty have been promoted to improve mechanical alignment, reduce alignment outliers and improve patient outcomes. The aim of this study was to compare the efficacy of patient-specific instrumentation (PSI) and conventional instrumentation (CI) in achieving neutral alignment and accurate component positioning in total knee arthroplasty. Methods: We conducted a double-blinded randomized controlled trial in which patients were randomly assigned to treatment with either PSI or CI. Results: Fifty-four patients were included in the study. No relevant improvement in coronal alignment was found between the PSI and CI groups with post-hoc power of 0.91. Tibial slope was found to be more accurately reproduced to the preoperative target of 3° with PSI than with CI (3.8°± 3.1° v. 7.7°± 3.6°, respectively, p < 0.001). There were no differences found in patient-reported outcome measures, surgical time or length of hospital stay. Conclusion: Given the added cost of the PSI technique, its use is difficult to justify given the small improvement in only a single alignment parameter. Clinical trial registration: Clinicaltrials.gov, no. NCT03416946

Contexte: L'utilisation de guides de coupe sur mesure dans l'arthroplastie totale du genou a été recommandée pour améliorer l'alignement mécanique, réduire les alignements extrêmes et améliorer les résultats des patients. Cette étude cherchait à comparer la capacité des instruments sur mesure et des instruments classiques à engendrer un alignement neutre et un bon positionnement des composants dans le cadre d'une arthroplastie totale du genou. Méthodes: Nous avons mené un essai clinique randomisé à double insu. Les patients étaient répartis aléatoirement entre le groupe de traitement avec instruments sur mesure et le groupe de traitement avec instruments classiques. Résultats: Cinquante-quatre patients ont participé à l'étude. Aucune différence notable de l'alignement coronal entre les groupes n'a été relevée, pour une puissance observée de 0,91. La pente tibiale correspondait plus exactement à la cible préopératoire de 3° avec les instruments sur mesure qu'avec les instruments classiques (3,8° ± 3,1° contre 7,7° ± 3,6°, respectivement; p < 0,001). Il n'y avait aucune différence dans les mesures déclarées par les patients, la durée de l'intervention et la durée d'hospitalisation. Conclusion: Étant donné l'amélioration minime d'un seul paramètre d'alignement et le coût supérieur de la technique sur mesure, son utilisation est difficile à justifier. Enregistrement de l'essai: Clinicaltrials.gov, no NCT03416946.

Does oxidized zirconium make a difference? Midterm cohort survivorship of symmetric posterior condyle posterior-stabilized total knee arthroplasty

Background: A novel symmetric posterior condylar design and option of a femoral component with an outer zirconium oxide layer were introduced to a successful asymmetric condylar total knee arthroplasty system in 2005. Given the paucity of information on this modified design, we performed a study to determine its early to midterm survivorship and performance. Methods: Patients who received the Genesis II Symmetric Posterior Condyle or Legion Primary total knee (cobalt­chromium [CoCr] or oxidized zirconium­niobium [OxZr]) (Smith & Nephew) implanted at the study centre between March 2007 and December 2013 were enrolled into a prospective database. We retrospectively reviewed the database and performed survival analysis using Kaplan­Meier techniques. Results: There were 2178 patients (1359 women [62.4%]; mean age 64.6 yr; mean body mass index 35.0) with 2815 knee replacements available for analysis. Survival rates were 98.2% (95% confidence interval [CI] 97.6%­98.7%) for failure for any reason at 2 years and 96.8% (95% CI 96.0%­97.7%) at 5 years. Age (hazard ratio [HR] 0.97, 95% CI 0.94­0.997) and female sex (HR 0.45, 95% CI 0.27­0.75) were protective, whereas body mass index (HR 1.02, 95% CI 0.99­1.05) and OxZr implant (HR 1.11, 95% CI 0.57­2.18) did not influence survivorship. Oxford Knee Score values improved from a mean of 40.2 to 21.8 by 2 years (p < 0.001), with no difference between the CoCr and OxZr groups. Conclusion: The symmetric posterior condylar posterior-stabilized knee offers excellent midterm survivorship. Implant bearing surface did not have an influence on survivorship to 5 years, and, thus, use of OxZr implants may not be justified.

Contexte: Un nouveau modèle à condyles postérieurs symétriques et l'option d'un élément fémoral pourvu d'une couche d'oxyde de zirconium ont été introduits avec succès dans un système de prothèse totale du genou à condyles asymétriques en 2005. Compte tenu du manque de renseignements concernant ce modèle modifié, nous avons procédé à une étude pour en déterminer la survie et le rendement à court et à moyen terme. Méthodes: Les patients ayant reçu la prothèse à condyles postérieurs symétriques Genesis II ou une prothèse totale primaire Legion (au cobalt­chrome [CoCr] ou au zirconium­niobium oxydé [OxZr]) (Smith & Nephew) au centre de recherche entre mars 2007 et décembre 2013 ont été inscrits dans une base de données prospective. Nous avons procédé à une revue rétrospective de la base de données et effectué une analyse de survie à l'aide de techniques de Kaplan­Meier. Résultats: On a dénombré 2178 patients (dont 1359 femmes [62,4 %]; âge moyen 64,6 ans; indice de masse corporelle moyen 35,0) totalisant 2815 arthroplasties du genou pour analyse. Les taux de survie ont été de 98,2 % (intervalle de confiance [IC] à 95 % 97,6 %­98,7 %) pour le paramètre défaillance de toutes causes à 2 ans et de 96,8 % (IC à 95 % 96,0 %­97,7 %) à 5 ans. L'âge (risque relatif [RR] 0,97, IC à 95 % 0,94­0,997) et le fait d'être de sexe féminin (RR 0,45, IC à 95 % 0,27­0,75) ont conféré un effet protecteur, tandis que l'indice de masse corporelle (RR 1,02, IC à 95 % 0,99­1,05) et l'implant OxZr (RR 1,11, IC à 95 % 0,57­2,18) n'ont eu aucune influence sur la survie. Les scores Oxford d'évaluation du genou se sont améliorés, passant d'une moyenne de 40,2 à 21,8 en l'espace de 2 ans (p < 0,001), sans différence entre les groupes CoCr et OxZr. Conclusion: La prothèse du genou à condyles postérieurs symétriques postéro-stabilisée possède une excellente survie à moyen terme. La surface portant l'implant n'a pas eu d'influence sur la survie à 5 ans et, donc, l'utilisation d'implants OxZr ne sera peutêtre pas justifiée.

Mortality effects of timing alternatives for hip fracture surgery.

BACKGROUND: The appropriate timing of hip fracture surgery remains a matter of debate. We sought to estimate the effect of changes in timing policy and the proportion of deaths attributable to surgical delay. METHODS: We obtained discharge abstracts from the Canadian Institute for Health Information for hip fracture surgery in Canada (excluding Quebec) between 2004 and 2012. We estimated the expected population-average risks of inpatient death within 30 days if patients were surgically treated on day of admission, inpatient day 2, day 3 or after day 3. We weighted observations with the inverse propensity score of surgical timing according to confounders selected from a causal diagram. RESULTS: Of 139 119 medically stable patients with hip fracture who were aged 65 years or older, 32 120 (23.1%) underwent surgery on admission day, 60 505 (43.5%) on inpatient day 2, 29 236 (21.0%) on day 3 and 17 258 (12.4%) after day 3. Cumulative 30-day in-hospital mortality was 4.9% among patients who were surgically treated on admission day, increasing to 6.9% for surgery done after day 3. We projected an additional 10.9 (95% confidence interval [CI] 6.8 to 15.1) deaths per 1000 surgeries if all surgeries were done after inpatient day 3 instead of admission day. The attributable proportion of deaths for delays beyond inpatient day 2 was 16.5% (95% CI 12.0% to 21.0%). INTERPRETATION: Surgery on admission day or the following day was estimated to reduce postoperative mortality among medically stable patients with hip fracture. Hospitals should expedite operating room access for patients whose surgery has already been delayed for nonmedical reasons.