A population-based nested case-control study of the costs of hip and knee replacement surgery

Identification of Surgeon Outliers to Improve Cost Efficiency: A Novel Use of the Centers for Medicare and Medicaid Quality Payment Program

BACKGROUND

Bundled payment programs for total joint arthroplasty (TJA) have become popular among both private and public payers. Because these programs provide surgeons with financial incentives to decrease costs through reconciliation payments, there is an advantage to identifying and emulating cost-efficient surgeons. The objective of this study was to utilize the Centers for Medicare and Medicaid Services (CMS) Quality Payment Program (QPP) in combination with institutional data to identify cost-efficient surgeons within our region and, subsequently, identify cost-saving practice patterns.

METHODS

Data was obtained from the CMS QPP for total knee arthroplasty (TKA) and total hip arthroplasty (THA) surgeons within a large metropolitan area from January 2019 to December 2021. A simple linear regression determined the relationship between surgical volume and cost-efficiency. Internal practice financial data determined whether patients of identified surgeons differed with respect to x-ray visits, physical therapy visits, out-of-pocket payments to the practice, and whether surgery was done in hospital or surgical center settings.

RESULTS

There were 4 TKA and 3 THA surgeons who were cost-efficiency outliers within our area. Outliers and nonoutlier surgeons had patients who had similar body mass index, American Society of Anesthesiologists Physical Status Score, and age-adjusted Charlson Comorbidity Index scores. Patients of these surgeons had fewer x-ray visits for both TKA and THA (1.06 versus 1.11, P < .001; 0.94 versus 1.15, P < .001) and lower out-of-pocket costs ($86.10 versus $135.46, P < .001; $116.10 versus $177.40, P < .001). If all surgeons performing > 30 CMS cases annually within our practice achieved similar cost-efficiency, the savings to CMS would be $17.2 million for TKA alone ($75,802,705 versus $93,028,477).

CONCLUSIONS

The CMS QPP can be used to identify surgeons who perform cost-efficient surgeries. Practice patterns that result in cost savings can be emulated to decrease the cost curve, resulting in reconciliation payments to surgeons and institutions and cost savings to CMS.

Socioeconomic Disparities in Online Patient Portal Utilization Among Total Knee Arthroplasty Recipients

BACKGROUND

Since 2021, the Centers for Medicare and Medicaid Services have mandated that patients have open access to their medical records. Many institutions use online portals, which allow patients to access their health information and communicate with care teams. Our research aimed to evaluate demographic patterns for online patient portal utilization in patients undergoing total knee arthroplasty (TKA). Further, we assessed if and how portal engagement contributes to perioperative outcomes.

METHODS

This study retrospectively reviewed primary and elective TKA from 2017 to 2022 at a single academic institution. Patients were stratified into 2 groups based on their online portal status: activated (A) or not-activated (NA). Baseline characteristics and postoperative outcomes were collected from the electronic medical record and compared.

RESULTS

In total, 10,995 patients were included: 8,330 (75.8%) were A and 2,625 (24.2%) were NA. The NA group was significantly older (P < .001); more likely to be Black (P < .001), women (P < .001), single/divorced/widowed (P < .001), non-English speaking (P < .001), and Medicare or Medicaid insured (P < .001); from zip codes with median incomes below $50,000 (P < .001), and more likely to be American Society of Anesthesiologists class III or IV (P < .001). Patient-reported outcome measure completion rates were significantly lower in the NA group (15.3 versus 47.7%, P < .001). Lengths of stay (LOS) were significantly higher in the NA group (2.7 versus 2.1 days, P < .001). The NA group was significantly more likely to be discharged to skilled nursing facilities (P < .001). Comparable rates of 90-day emergency department visits, readmissions, as well as 90-day and 2-year revisions, were observed across groups.

CONCLUSIONS

There are significant disparities in online portal activation status based on patient demographics. Patients who have A portals had significantly higher Patient-reported outcome measure completion rates, shorter LOS, and higher rates of home discharge. Further research should determine which other factors may affect patient portal utilization and inform interventions to improve portal utilization among minority populations.

Association between physical activity status and musculoskeletal pain in individuals infected with SARS-CoV-2: Sulcovid-19 survey

BACKGROUND

This study aimed to evaluate the association of physical activity (PA) before SARS-Cov-2 infection with Musculoskeletal (MSK) pain after infection.

METHODS

We used data from the Sulcovid-19, a longitudinal study. This study was carried out in the city of Rio Grande, in the extreme south of Brazil with individuals who were infected by SARS-Cov-2 between December/2020 and March/2021. Participants were asked on MSK pain in the cervical, thoracic, low back, upper and lower limbs. Three PA variables were built, as follows: 1) any PA (yes or no), 2) sufficient PA (based on WHO recommendations), and 3) PA status before and after COVID-19 (i.e., remained inactive, became inactive, and remained active).

RESULTS

Participants reporting sufficient PA levels were less likely to experience pain in the cervical (PR 0.70, 0.53-0.92 95% CI) after COVID-19. Those who remained active were less likely to experience pain in the cervical spine and in at least one body site. Becoming inactive increased the likelihood of experiencing pain in the lower limbs after infection by 30%.

CONCLUSIONS

Continuous PA practice regardless SARS-Cov-2 infection showed important protection effect for MSK as a consequence of infection.

Patient appropriateness for total knee arthroplasty and predicted probability of a good outcome

OBJECTIVES

One-fifth of total knee arthroplasty (TKA) recipients experience a suboptimal outcome. Incorporation of patients' preferences in TKA assessment may improve outcomes. We determined the discriminant ability of preoperative measures of TKA need, readiness/willingness and expectations for a good TKA outcome.

METHODS

In patients with knee osteoarthritis (OA) undergoing primary TKA, we preoperatively assessed TKA need (Western Ontario-McMaster Universities OA Index (WOMAC) Pain Score and Knee injury and Osteoarthritis Outcome Score (KOOS) function, arthritis coping), health status, readiness (Patient Acceptable Symptom State, depressive symptoms), willingness (definitely yes-yes/no) and expectations (outcomes deemed 'very important'). A good outcome was defined as symptom improvement (met Outcome Measures in Rheumatology and Osteoarthritis Research Society International (OMERACT-OARSI) responder criteria) and satisfaction with results 1 year post TKA. Using logistic regression, we assessed independent outcome predictors, model discrimination (area under the receiver operating characteristic curve, AUC) and the predicted probability of a good outcome for different need, readiness/willingness and expectations scenarios.

RESULTS

Of 1,053 TKA recipients (mean age 66.9 years (SD 8.8); 58.6% women), 78.1% achieved a good outcome. With TKA need alone (WOMAC pain subscale, KOOS physical function short-form), model discrimination was good (AUC 0.67, 95% CI 0.63 to 0.71). Inclusion of readiness/willingness, depressive symptoms and expectations regarding kneeling, stair climbing, well-being and performing recreational activities improved discrimination (p=0.01; optimism corrected AUC 0.70, 0.66-0.74). The predicted probability of a good outcome ranged from 44.4% (33.9-55.5) to 92.4% (88.4-95.1) depending on level of TKA need, readiness/willingness, depressive symptoms and surgical expectations.

CONCLUSIONS

Although external validation is required, our findings suggest that incorporation of patients' TKA readiness, willingness and expectations in TKA decision-making may improve the proportion of recipients that experience a good outcome.

Surgical Scheduling Impacts Hospital Length of Stay and Associated Healthcare Costs for Patients Undergoing Total Hip and Knee Arthroplasty

BACKGROUND

Surgical scheduling, specifically the day of the week on which surgery is performed, has been associated with various postoperative outcomes in patients undergoing lower extremity joint arthroplasty.

PURPOSE

We sought to investigate surgical scheduling as a potential modifiable factor for patient quality metrics and related costs.

METHODS

In a retrospective prognostic study, all total knee and total hip arthroplasty (TKA/THA) cases that took place in 2017 to 2018 at a multihospital academic health system were queried. Patients were separated by the day of the week the surgery was performed, with Monday/Tuesday compared to Thursday/Friday. Outcomes included length of stay (LOS) (extended LOS defined as 3 days or longer), cost, and complications. Multivariable regression models measured associations between scheduling of surgery and outcomes; odds ratios (OR) and 95% confidence intervals (CIs) are reported.

RESULTS

Overall, 1,571 TKA and 992 THA patients were included (65% and 35%, respectively, performed on Monday/Tuesday and 70% and 30%, respectively, performed on Thursday/Friday). Patients undergoing TKA on Monday/Tuesday versus Thursday/Friday had higher American Society of Anesthesiologists scores (42% vs 33% with score of 3 or higher) but less often an extended LOS (31% vs 54%; adjusted OR: 2.76, 95% CI: 2.22-3.46), lower skilled nursing facility costs (unadjusted mean, $12,515 vs $14,154) and lower home health aide costs (unadjusted mean, $3,793 vs $4,192). Similar patterns were observed in THA patients.

CONCLUSION

These results from institutional data suggest that surgical scheduling is a modifiable factor possibly associated with postoperative outcomes. Furthermore, more rigorous study is warranted.

The Effect of Patient Age and Surgical Appropriateness and Their Influence on Surgeon Recommendations for Primary TKA: A Cross-Sectional Study of 2,037 Patients

BACKGROUND

Rising total knee arthroplasty (TKA) rates in younger patients raises concern about appropriateness. We asked: are younger individuals who seek consultation for TKA less likely to be appropriate for and, controlling for appropriateness, more likely to be recommended for surgery?

METHODS

This cross-sectional study was nested within a prospective cohort study of knee osteoarthritis (OA) patients referred for TKA from 2014 to 2016 to centralized arthroplasty centers in Alberta, Canada. Pre-consultation, questionnaires assessed patients' TKA appropriateness (need, based on knee symptoms and prior treatment; readiness/willingness to undergo TKA; health status; and expectations) and contextual factors (for example, employment). Post-consultation, surgeons confirmed study eligibility and reported their TKA recommendation. Using generalized estimating equations to control for clustering by surgeon, we assessed relationships between patient age (<50, 50 to 59, ≥60 years) and TKA appropriateness and receipt of a surgeon TKA recommendation.

RESULTS

Of 2,037 participants, 3.3% and 22.7% were <50 and 50 to 59 years of age, respectively, 58.7% were female, and 35.5% were employed. Compared with older participants, younger participants reported significantly worse knee symptoms, higher use of OA therapies, higher TKA readiness, and similar willingness, but had higher body mass index and were more likely to smoke and to consider the ability to participate in vigorous activities, for example, sports, as very important TKA outcomes. TKA was offered to 1,500 individuals (73.6% overall; 52.2%, 71.0%, and 75.4% of those <50, 50 to 59, and ≥60 years, respectively). In multivariate analyses, the odds of receiving a TKA recommendation were higher with greater TKA need and willingness, in nonsmokers, and in those who indicated that improved ability to go upstairs and to straighten the leg were very important TKA outcomes. Controlling for TKA appropriateness, patient age was not associated with surgeons' TKA recommendations.

CONCLUSIONS

Younger individuals with knee OA referred for TKA had similar or greater TKA need, readiness, and willingness than older individuals. Incorporation of TKA appropriateness criteria into TKA decision-making may facilitate consideration of TKA benefits and risks in a growing population of young, obese individuals with knee OA.

CLINICAL RELEVANCE

Younger people seeking TKA for knee OA had significant OA pain and disability despite recommended OA therapies, suggesting appropriateness for surgical consideration. However, they were significantly more likely to have morbid obesity, to smoke, and to consider return to vigorous activities, like sport, as important TKA outcomes. Whether the short- and longer-term risks of TKA are outweighed by the benefits is unclear and warrants additional research.

Comparative effectiveness of nonsurgical interventions in the treatment of patients with knee osteoarthritis: A PRISMA-compliant systematic review and network meta-analysis

BACKGROUND

To find out, based on the available recent randomized controlled trials (RCTs), if the nonsurgical interventions commonly used for knee osteoarthritis patients are valid and quantify their efficiency.

METHODS

The database of MEDLINE and EMBASE were searched for RCTs evaluating nonsurgical treatment strategies on patients with mild to moderate knee osteoarthritis. A Bayesian random-effects network meta-analysis was performed. The primary outcome was the mean change from baseline in the Western Ontario and McMaster university (WOMAC) total score at 12 months. Raw mean differences with 95% credibility intervals were calculated. Treatments were ranked by probabilities of each treatment to be the best.

RESULTS

Thirteen trials assessed 7 strategies with WOMAC at 12 months: injection of platelet rich plasma (PRP), corticosteroids, mesenchymal stem cells (MSCs), hyaluronic acid, ozone, administration of nonsteroidal anti-inflammatory drugs with or without the association of physiotherapy. For treatment-specific effect size, a greater association with WOMAC decrease was found significantly for MSCs (mean difference, -28.0 [95% CrI, -32.9 to -22.4]) and PRP (mean difference, -19.9 [95% CrI, -24.1 to -15.8]). Rank probabilities among the treatments indicated that MSCs had a much higher probability (P = .91) of being the best treatment compared with other treatments, while PRP ranked as the second-best treatment (P = .89).

CONCLUSION

In this systematic review and network meta-analysis, the outcomes of treatments using MSCs and PRP for the management of knee osteoarthritis were associated with long-term improvements in pain and function. More high quality RCTs would be needed to confirm the efficiency of MSCs and PRP for the treatment of patients with knee osteoarthritis.

Effect of an Elevated Preoperative International Normalized Ratio on Transfusion and Complications in Primary Total Hip Arthroplasty with the Enhanced Recovery after Surgery Protocol

Objective

To verify whether an elevated preoperative international normalized ratio (INR) increases transfusion and complications independently in primary total hip arthroplasty (THA) with the management of an enhanced recovery after surgery (EARS) protocol.

Methods

We retrospectively reviewed the database of adults who underwent primary THA between 2014 and 2018 by the same surgeon. A total of 552 patients were assigned into three groups by preoperative INR class: INR ≤ 0.9, 0.9 < INR < 1.0, and INR ≥ 1.0. We regarded transfusion within 90 days during the same hospitalization as the primary outcome. We also included perioperative blood loss, maximum Hb drop, postoperative anaemia requiring medicine, and length of hospital stay (LOS) during the same hospitalization in the study. Complications and reoperation at 90 days and mortality at 90 days and 12 months were also included in the study. Univariable analyses were utilized to compare baselines and outcomes among the three groups. Multivariate logistic regressions were used to adjust for differences at baseline among the groups.

Results

All patients had an INR < 1.5 preoperatively and were managed with the ERAS protocol. Among them, 93 (16.8%) patients had INR ≤ 0.9, 268 (48.6%) patients had 0.9 < INR < 1.0, and 191 (34.6%) patients had INR ≥ 1.0. In the univariable analyses, as the INR increased, the transfusion rates increased from 1.08% for INR ≤ 0.9, to 1.12% for 0.9 < INR < 1.0 and to 5.76% for INR ≥ 1.0 (P < 0.05). The overall complication rate increased from 10.8% for INR ≤ 0.9, to 16.4% for 0.9 < INR < 1.0, and to 22.5% for INR ≥ 1.0 (P < 0.05). The length of stay (LOS) in the INR ≥ 1.0 group was 5.7 ± 2.2 days, which was significantly longer than that in the INR ≤ 0.9 group (4.7 ± 1.6 days, P = 0.000) and 0.9 < INR < 1.0 group (5.1 ± 2.0 days, P = 0.007). No statistical significance was detected among the groups regarding blood loss, maximum Hb drop, or the incidence of postoperative anaemia that required medicine. There was no significant difference in reoperation or mortality among the groups. When controlling for demographic and comorbidity characteristics, there was no statistically significant difference in the odds of transfusion during the same hospitalization or overall complications at 90 days among the groups (P > 0.05).

Conclusions

Elevated preoperative INR cannot increase transfusion or complication rates independently in primary THA with the management of the ERAS protocol. With the improvement in the ERAS protocol and the use of tranexamic acid (TXA), an INR < 1.5 is still a conventional safe threshold for THA surgery.

Clinical efficacy and cost-effectiveness of postoperative radiographs after total knee arthroplasty

BACKGROUND

Postoperative radiographs are commonly ordered after primary total knee arthroplasty (TKA), however, there is limited data on how often these films change management over the entire postoperative time course, and what should prompt imaging to maximize clinical utility.

METHODS

A retrospective cohort study was conducted of patients ≥ 18 years old who underwent a primary TKA at two level one trauma centers. Postoperative data were collected to determine the frequency of postoperative radiograph series, radiograph findings that did not suggest normal healing or alignment to radiologist and orthopedists, and changes in postoperative management. The total cost and radiation exposure values were calculated for all patient radiographs using estimates from previous literature.

RESULTS

From the 1258 patients included, 3831 postoperative radiographs were taken (mean ± 95% confidence interval [CI]: 3.05 ± 0.11 radiographs per patient). Of these 3831 radiographs, 44 (1.1%) contained a positive radiographic finding. Only 13 (0.3% of radiographs) of these positive radiographic findings were positive orthopaedic findings, 11 of which led to changes in management. For all but 1 of these patients (10/11, 91%), these radiographs were taken during a non-routine postoperative visit. Routine postoperative radiographs that did not change management cost $1,008,480 and administered 22.92 mSV of radiation to patients within this study.

CONCLUSION

Postoperative radiography obtained after primary TKA were of low clinical utility yet resulted in considerable healthcare costs and unnecessary radiation burden. Radiographs ordered during a non-routine visit, however, were a reliable indicator of when this imaging provided clinical utility.

Time Required for Planned and Unplanned Episodes of Care in Primary Total Joint Arthroplasty: Has Anything Changed With a Growth in Outpatient Arthroplasty?

BACKGROUND

This study sought to determine the total amount of time committed to planned and unplanned episodes of care related to primary, unilateral total joint arthroplasty (TJA), relative to a growth in outpatient TJA.

METHODS

All primary, unilateral TJA procedures performed over a 7-year period by a single surgeon at a single institution were retrospectively reviewed. Time dedicated to planned work was calculated over each episode of care, from surgery scheduling to 90 days postoperatively. All telephone inquiries and readmissions involving the surgeon's direct input, over the episode of care, constituted time dedicated to unplanned work.

RESULTS

Between 2012 and 2018, as the proportion of outpatient TJAs increased, the average planned episode-of-care time per patient decreased from 412 minutes to 361 minutes. Despite a 108% increase in the total number of outpatient TJAs between 2017 and 2018 (51/432 (11.8%) to 106/555 (19.1%); P = .002), neither the average number of unplanned telephone inquiries (4.6 ± 3.8 vs 4.2 ± 3.7; P = .124), nor the mean time per patient required to respond to calls (23.1 ± 19.4 vs 21.2 ± 18 minutes, P = .135) differed. Between 2017 and 2018, the average total episode-of-care time per patient decreased from 403 minutes (376 planned + 27 unplanned) to 387 minutes (361 planned + 26 unplanned).

CONCLUSION

Despite an increase in outpatient TJA, the average time required for planned and unplanned patient care remained relatively constant. The growth of outpatient TJA nationally should not trigger a change in Centers for Medicare and Medicaid Services benchmarks.

The association of anaemia and its severity with composite morbidity after total hip arthroplasty

BACKGROUND

Total hip arthroplasty (THA) is a common orthopaedic procedure and is expected to increase with an increasing elderly population. Many of these patients suffer from chronic diseases which might be associated with anaemia. Anaemia, by itself, increases the risk of morbidity. We aimed to delineate relationship between preoperative anaemia and postoperative composite morbidities in patients undergoing primary THA.

METHODS

A cohort study analysed the data from the American College of Surgeons National Surgical Quality Improvement Program 2008-2014 database. Adult patients who underwent unilateral primary THA were included and divided into 3 groups: no anaemia, mild anaemia, and moderate-to-severe anaemia. Thirty-day mortality and morbidity were recorded as adverse events. The associations between anaemia, baseline characteristics, and adverse events were analysed after adjusting for confounders.

RESULTS

Moderate-to-severe anaemia patients were at increased risk for composite morbidity (adjusted odds ratio, 1.43 [1.17-1.74]) when compared to non-anaemics. The stratification revealed a significant effect of younger age, male gender, white race, obesity, general anaesthesia, and mean operative time >120 minutes in patients with moderate-to-severe anaemia. These patients were also at a higher risk of developing several specific morbidities.

CONCLUSION

Moderate-to-severe anaemia increases the risk for composite morbidities, but not mortality in patients undergoing primary THA. Further studies are needed to assess whether preoperative management of moderate-to-severe anaemia would improve outcomes in patients undergoing THA.

Effects of mechanical interventions in the management of knee osteoarthritis: protocol for an OA Trial Bank systematic review and individual participant data meta-analysis

INTRODUCTION

Knee osteoarthritis (OA) is a prevalent and disabling musculoskeletal condition. Biomechanical factors may play a key role in the aetiology of knee OA, therefore, a broad class of interventions involves the application or wear of devices designed to mechanically support knees with OA. These include gait aids, bracing, taping, orthotics and footwear. The literature regarding efficacy of mechanical interventions has been conflicting or inconclusive, and this may be because certain subgroups with knee OA respond better to mechanical interventions. Our primary aim is to identify subgroups with knee OA who respond favourably to mechanical interventions.

METHODS AND ANALYSIS

We will conduct a systematic review to identify randomised clinical trials of any mechanical intervention for the treatment of knee OA. We will invite lead authors of eligible studies to share individual participant data (IPD). We will perform an IPD meta-analysis for each type of mechanical intervention to evaluate efficacy, with our main outcome being pain. Where IPD are not available, this will be achieved using aggregate data. We will then evaluate five potential treatment effect modifiers using a two-stage approach. If data permit, we will also evaluate whether biomechanics mediate the effects of mechanical interventions on pain in knee OA.

ETHICS AND DISSEMINATION

No new data will be collected in this study. We will adhere to institutional, national and international regulations regarding the secure and confidential sharing of IPD, addressing ethics as indicated. We will disseminate findings via international conferences, open-source publication in peer-reviewed journals and summaries posted on websites serving the public and clinicians.

PROSPERO REGISTRATION NUMBER

CRD42020155466.

Knee Injury and Osteoarthritis Outcome Score (KOOS) Responder Criteria and Minimal Detectable Change 3-12 Years Following a Youth Sport-Related Knee Injury

The applicability of thresholds that constitute an acceptable score or meaningful change on the Knee injury and Osteoarthritis Outcome Score (KOOS) in cohorts ≥ 5 years following knee injury is not well understood. The primary objective of this study was to evaluate the association between intra-articular knee injury type and two different KOOS pain thresholds (patient acceptable symptom state (PASS) and Englund symptomatic knee criteria) in the Alberta Youth Prevention of Osteoarthritis (PrE-OA) cohort, which includes participants 3–12 years following a youth sport-related knee injury and uninjured controls with similar age, sex and sport characteristics. Analyses accounted for sex, time since injury and the interaction between time since injury and injury type. Secondary objectives were to report proportions meeting thresholds for KOOS outcomes and minimal detectable change (MDC) from published test–retest reliability data, over a 1–4-year follow-up. Two hundred and fifty-three (253) participants (124 injured, 129 controls) were included in analyses, of which 153 (77 injured, 76 controls) had follow-up data. Similar odds were observed for presence of pain (below PASS threshold) in participants with anterior cruciate ligament (ACL)/meniscus injury (odds ratio (OR) 4.2 (97.5% confidence interval (CI): 1.8, 9.9)) and other knee injuries (OR 4.9 (97.5% CI: 1.2, 21.0)), while there were higher odds for presence of Englund “symptomatic knee” criteria in participants with ACL/meniscus injury (OR 13.6 (97.5% CI: 2.9, 63.4)) than other knee injuries (OR 7.3 (97.5% CI: 0.8, 63.7)) compared to controls. After a median 23.4 (8 to 42) month follow-up, 35% of previously injured participants had at least one KOOS sub-scale score that worsened by more than the MDC published threshold. Despite limited research, this study shows that individuals with youth sport knee injuries other than ACL or meniscus injury may also experience significant pain and symptoms 3–12 years following injury. Replication and further follow-up are needed to identify a possible clinical trajectory towards osteoarthritis.

The Relationship between Patient-Reported Readiness for Total Knee Arthroplasty and Likelihood of a Good Outcome at One Year

OBJECTIVE

To determine the relationship between patients' pre-operative readiness for total knee arthroplasty (TKA) and surgical outcome at one-year.

METHODS

This prospective cohort study recruited knee osteoarthritis (OA) patients aged 30+ years referred for TKA at two hip/knee surgery centers in Alberta, Canada. Those who received primary, unilateral TKA completed questionnaires pre-TKA to assess WOMAC-pain, KOOS-physical function, Perceived Arthritis Coping Efficacy, General Self-Efficacy, PHQ-8, BMI, comorbidities and TKA readiness (Patient Acceptable Symptom State; willingness to undergo TKA), and one-year post-TKA to assess outcomes. A good TKA outcome was defined as improved knee symptoms (OARSI-OMERACT responder criteria) AND overall satisfaction with results. Poisson regression with robust error estimation was used to estimate relative risk of a good outcome for exposures, before and after controlling for covariates.

RESULTS

Of 1,272 TKA recipients assessed at one year, 1,053 with data for our outcome were included (mean age 66.9 years (SD 8.8); 58.6% female). Most (87.8%) were definitely willing to undergo TKA and had 'unacceptable' knee symptoms (79.7%). 78.1% achieved a good TKA outcome. Controlling for pre-TKA OA-related disability, arthritis coping efficacy, comorbid hip symptoms and depressed mood, definite willingness to undergo TKA and unacceptable knee symptoms were associated with greater likelihood of a good TKA outcome (adjusted RRs 1.18, 95% CI 1.04-1.35, and 1.14, 95% CI 1.02-1.27, respectively).

CONCLUSION

Among TKA recipients for knee OA, patients' psychological readiness and willingness for TKA were associated greater likelihood of a good outcome. Incorporation of these factors in TKA decision-making may enhance patient outcomes and appropriate use of TKA.

Is There Benefit in Keeping Early Discharge Patients Overnight After Total Joint Arthroplasty?

BACKGROUND

Total joint arthoplasty (TJA) cost containment has been a key focus for the Centers for Medicare and Medicaid Services spawning significant research and programmatic change, including a move toward early discharge and outpatient TJA. TJA outpatients receive few, if any, medical interventions before discharge, but the type and quantity of interventions provided for TJA patients who stay overnight in the hospital is unknown. This study quantified the nature, frequency, and outcome of interventions occurring overnight after primary TJA.

METHODS

1725 consecutive primary unilateral TJAs performed between 2012 and 2017 by a single surgeon in a rapid-discharge program, managed by a perioperative internal medicine specialist, were reviewed. Medical records were examined for diagnostic tests, treatments, and procedures, results of interventions, and readmissions.

RESULTS

759 patients were discharged on postoperative day 1. Eighty-four percent (641 of 759) received no medical interventions during their overnight hospital stay. Twelve (1.6%) received diagnostic tests, 90 (11.9%) received treatments, and 29 (3.8%) received procedures. Ninety-two percent (11 of 12) of diagnostic tests were negative, 66% of 100 treatments in 90 patients were intravenous fluids for oliguria or hypotension, and all procedures were in and out catheterizations for urinary retention. 90-day all-cause readmission rates were similar in patients who received (2.5%) and did not receive (3.3%) a clinical intervention.

CONCLUSION

Most patients received no overnight interventions, suggesting unnecessary costly hospitalization. The most common issues addressed were oliguria, urinary retention, and hypotension. Protocols to prevent these conditions would facilitate outpatient TJA, improve patient safety, and reduce costs.

Safety of Same and Next Day Discharge Following Revision Hip and Knee Arthroplasty Using Modern Perioperative Protocols

BACKGROUND

Advances in perioperative care have enabled early discharge and outpatient primary total joint arthroplasty (TJA). However, the safety of early discharge after revision TJA (rTJA) remains unknown and the COVID-19 pandemic will force decreased hospitalization. This study compared 90-day outcomes in patients undergoing aseptic rTJA discharged the same or next day (early) to those discharged 2 or 3 days postoperatively (later).

METHODS

In total, 530 aseptic rTJAs performed at a single tertiary care referral center (December 5, 2011 to December 30, 2019) were identified. Early and later discharge patients were matched as closely as possible on procedure type, sex, American Society of Anesthesiologists physical status classification, age, and body mass index. All patients were optimized using modern perioperative protocols. The rate of 90-day emergency department (ED) visits and hospital admissions was compared between groups.

RESULTS

In total, 183 early discharge rTJAs (54 hips, 129 knees) in 178 patients were matched to 183 later discharge rTJAs (71 hips, 112 knees) in 165 patients. Sixty-two percent of the sample was female, with an overall average age and body mass index of 63 ± 9.9 (range: 18-92) years and 32 ± 6.9 (range: 18-58) kg/m². There was no statistical difference in 90-day ED visit rates between early (6/178, 3.4%) and later (11/165, 6.7%) discharge patients (P = .214). Ninety-day hospital admission rates for early (7/178, 3.9%) and later (4/165, 2.4%) discharges did not differ (P = .545).

CONCLUSION

Using modern perioperative protocols with appropriate patient selection, early discharge following aseptic rTJA does not increase 90-day readmissions or ED visits. As hospital inpatient capacity remains limited due to COVID-19, select rTJA patients may safely discharge home the same or next day to preserve hospital beds and resources for more critical illness.

One-day Acceptance and Commitment Therapy workshop for preventing persistent post-surgical pain and dysfunction in at-risk veterans: A randomized controlled trial protocol

OBJECTIVE

Persistent post-surgical pain is common among patients undergoing surgery, is detrimental to patients' quality of life, and can precipitate long-term opioid use. The purpose of this randomized controlled trial is to assess the effects of a behavioral intervention offered prior to surgery for patients at risk for poor post-surgical outcomes, including persistent pain and impaired functioning.

METHODS

Described herein is an ongoing randomized, patient- and assessor-blind, attention-controlled multisite clinical trial. Four hundred and thirty Veterans indicated for total knee arthroplasty (TKA) with distress and/or pain will be recruited for this study. Participants will be randomly assigned to a one-day (~5 h) Acceptance and Commitment Therapy workshop or one-day education and attention control workshop. Approximately two weeks following their TKA surgery, patients receive an individualized booster session via phone. Following their TKA, patients complete assessments at 1 week, 6 weeks, 3 months, and 6 months.

RESULTS

The primary outcomes are pain intensity and knee-specific functioning; secondary outcomes are symptoms of distress and coping skills. Mediation analyses will examine whether changes in symptoms of distress and coping skills have an impact on pain and functioning at 6 months in Veterans receiving ACT. This study is conducted mostly with older Veterans; therefore, results may not generalize to women and younger adults who are underrepresented in this veteran population.

CONCLUSIONS

The results of this study will provide the first evidence from a large-scale, patient- and assessor-blind controlled trial on the effectiveness of a brief behavioral intervention for the prevention of persistent post-surgical pain and dysfunction.

Association Between Acupuncture and Knee Surgery for Osteoarthritis: A Korean, Nationwide, Matched, Retrospective Cohort Study

Objectives: The present study was undertaken to investigate the relationship between acupuncture therapy and surgery rate. Design: Matched, retrospective cohort study. Materials and Methods: From nationwide health insurance data (2002-2013 cohort data published by the National Health Insurance Service of Korea), patients with new cases of knee osteoarthritis that occurred between January 1, 2004 and December 31, 2010 were analyzed. Patients were divided into an acupuncture group (AG) and a control group (CG), based on records of acupuncture therapy. Propensity scores were calculated by using gender, age, income level, and Charlson comorbidity index (CCI), with the groups matched at a ratio of 1:3 (AG:CG). The final analysis period was 2 years after the first acupuncture therapy for AG and 2 years after initial diagnosis for CG; surgery rates were compared between the two groups. Stratified analyses were performed based on age, gender, and income level; sensitivity analyses were performed based on the frequency and duration of acupuncture therapy. Results: Propensity score-matched AG and CG included 8,605 and 25,815 subjects, respectively. Post-matching surgery rates were 0.26 and 0.93% in AG and CG, respectively. For all age groups, AG showed a lower surgery rate than CG. In the analysis based on gender, the female group showed a significantly lower hazard ratio of 0.225. In analysis based on income level, the results of the entire group were significant, with the lower income group showing the lowest hazard ratio. In sensitivity analyses, AG tended to show a lower surgery rate than CG. Conclusions: The present study demonstrated that acupuncture therapy is associated with a low rate of surgery for knee osteoarthritis. Additional studies are needed to support this conclusion.

Establishing an Orthopedic Excess Hospital Days in Acute Care Program

BACKGROUND

Excess days in acute care (EDAC) after total joint arthroplasty (TJA) represent a large economic burden. We developed an Orthopedic EDAC program that triages TJA patients to the appropriate service line (orthopedic vs medicine) and level of care (observation vs inpatient) on re-presentation. We developed and used evidence-based protocols for the treatment of TJA patients who are rehospitalized.

METHODS

We defined Orthopedic EDAC as the length of stay (LOS) during readmission and observation stays. Our target population included TJA and revision TJA patients. Patients between April 2017 and September 2017 and between October 2017 and September 2018 were defined as pre-implementation and post-implementation of the Orthopedic EDAC program, respectively.

RESULTS

A total of 2,662 patients underwent TJA and revision TJA during the pre-implementation and post-implementation periods. Twenty-three patients were managed on observation status during the study period. Readmissions decreased from 49 (6.1%) during pre-implementation to 37 (2.0%) during post-implementation (P = .004). By design, more rehospitalized patients were on the orthopedic surgery service after implementation of the Orthopedic EDAC program (n = 49; 70%) versus before (n = 22; 35%; P = .028). EDAC LOS decreased from 7.75 days to 4.73 days (P = .005).

CONCLUSION

In this single-center, before-after pilot of a novel Orthopedic EDAC program, we demonstrated a reduction in readmissions and Orthopedic EDAC LOS, as well as improved continuity of care for TJA patients on representation.

Comparative clinical and cost analysis between surgical and non-surgical intervention for knee osteoarthritis

OBJECTIVE

To evaluate the management and costs of osteoarthritis of the knee (OAK), a progressive joint disease due to bone and cartilage degeneration, with significant personal and societal impact.

METHODS

We prospectively analyzed the clinical outcomes and quantifiable cumulative direct costs of patients with OAK referred to our multidisciplinary OA program over a two year time period. One hundred thirty-one subjects were assessed. All demonstrated radiographic criteria for moderate to severe OAK. Western Ontario McMaster Osteoarthritis Index (WOMAC), Minimal Clinically Important Improvement (MCII), and change in BMI were recorded and analyzed. Total medical and surgical direct costs for all subjects during the two year time period were determined.

RESULTS

Five patients underwent total joint replacement during the two years of study. Among the group as a whole, a significant overall improvement in WOMAC scores was noted at the two year time point follow-up. After dividing the group into tertiles by baseline WOMAC scores, 46% achieved MCII. Significant weight loss was noted for individuals with baseline BMI of > 30. As all patients were considered "de facto" surgical candidates at referral, an average net savings of $9551.10 of direct costs per patient, or a potential total of $1,203,438.60 for the entire group, could be inferred as a result of medical as opposed to surgical management.

CONCLUSION

These findings support the benefits of multidisciplinary medical management for patients with significant OAK. This approach is clinically beneficial and may provide significant cost savings. Such models of care can substantially improve the long-term outcome of this highly prevalent condition and reduce societal and financial burdens.

Factors associated with emergency department presentation after total joint arthroplasty: a population-based retrospective cohort study

BACKGROUND

Unplanned visits to the emergency department after total joint arthroplasty are far more common than unplanned readmissions. Our objectives were to characterize the prevalence of presentation to an emergency department for any reason after total joint arthroplasty and to identify risk factors for such visits.

METHODS

Using health administrative databases, we conducted a population-based retrospective cohort study of adults (19-89 yr of age) who received their first primary elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) procedure for arthritis between April 2011 and March 2016 in Ontario. We made univariate comparisons between patients who presented to the emergency department within 30 days of surgery and those who did not in. We determined differences in use of health care services between groups by comparing the change in use in the year before and after surgery between patients who presented to the emergency department and those who did not. We developed logistic regression models for the occurrence of an emergency department visit using backward variable elimination.

RESULTS

We identified 42 273 total hip recipients and 70 725 total knee recipients, of whom 5640 (13.3%) and 11 224 (15.9%), respectively, presented to the emergency department within 30 days of surgery. Fewer than 1% of these patients required admission, and nearly half (45%) went to a different institution from where they had their surgery. Among both THA and TKA recipients, patients who presented to the emergency department had a net increase in their median annual health care costs (THA: $501, TKA: $682), compared to a net decrease for the cohort as a whole. Factors associated with increased risk of an emergency visit included increased patient age, male sex, rural residence and various comorbidities. Predictive regression models showed poor discriminative ability for both THA (C-statistic 0.57) and TKA (C-statistic 0.58) recipients.

INTERPRETATION

One in 7 patients presented to the emergency department within 30 days of THA or TKA. Some may conceivably have been managed remotely, and very few required readmission. There is a crucial need for strategies to minimize these events.

Five Questions to Identify Patients With Osteoarthritis of the Knee

BACKGROUND

To treat the increasing number of patients with osteoarthritis (OA) of the knee, high-volume institutions rely on central referral services as first contact point. Depending on the grading of arthritis, patients will be referred to a nonoperative or operative care provider. The present study reports on a simple 5-step questionnaire to identify patients with OA (Kellgren/Lawrence [KL] grade ≥2) of the knee to improve efficiency of referrals.

METHODS

We included 998 patients who contacted the physician referral service at the author's institution complaining of knee pain and divided them into 2 groups. The study group included patients with an appointment and consisted of 646 patients (345 women [53.4%] and 301 men [46.6%]). X-rays of the knee were graded according to the KL classification system. The control group of patients who did not make an appointment consisted of 352 patients (187 women [53.1%] and 165 men [46.9%]). These patients were contacted to evaluate whether they had been diagnosed with OA of the knee since their initial call, to assure that the study group was not exposed to a selection bias.

RESULTS

Logistic regression revealed 5 questions as significant predictors for OA of the knee (KL grade ≥2). When combining both groups, an 86.9% sensitivity, a 73.3% specificity, and an 84.3% overall accuracy were reached, when patients answered 3 or more questions positively.

CONCLUSION

The present study revealed a simple 5-step questionnaire to identify patients with OA of the knee. Implementation of the questionnaire has the potential to improve the accuracy of referral processes and streamline organization before the first appointment.

Optimization of Orthopedic Surgical Instrument Trays: Lean Principles to Reduce Fixed Operating Room Expenses

BACKGROUND

Optimization of surgical instrument trays improves efficiency and reduces cost. The purpose of this study is to assess the economic impact of optimizing orthopedic instrument trays at a tertiary medical center.

METHODS

Twenty-three independent orthopedic surgical instrument trays at a single academic hospital were reviewed from 2017 to 2018. Using Lean methodology, surgeons agreed upon the fewest number of instruments needed for each of the procedure trays. Instrument usage counts, cleaning times, room turnover times, tray weight, holes in tray wrapping, wet trays, and time invested to optimize each tray were tracked. Cost savings were calculated. Student's t-test was used to determine statistical significance, with P < .05 considered significant.

RESULTS

The mean instrument usage before and after Lean optimization was 23.4% and 54.2% (P < .0001). By Lean methods, 433 of 792 instruments (55%) were removed from 11 unique instrument trays (102 total trays), resulting in a reduction of 3520 instruments. Total weight reduction was 574.3 pounds (22%), ranging from 2.1-16.2 pounds per tray. The number of trays with wrapping holes decreased from 13 to 1 (P < .0001). The process of examining and removing instruments took an average of 7 minutes 35 seconds per tray. The calculated total annual savings was $270,976 (20% overall cost reduction).

CONCLUSION

In addition to substantial cost savings, tray optimization decreases tray weights and cleaning times without negatively impacting turnover times. Lean methodology improves efficiency in instrument tray usage, and reduces hospital cost while encouraging surgeon and staff participation through continuous process improvement.

LEVEL OF EVIDENCE

Economic Quality Improvement, Level III.

Reasons for continuing physiotherapy treatment after a high-intensity physyiotherapy program in patients after total knee arthroplasty: a mixed-methods study

Background: Patients after total knee arthroplasty treated with a 10-day high-intensity physiotherapy program in a resort were expected to recover fast without need for a longer physiotherapy treatment period.Objective: To explore the expectations and experiences of patients with total knee arthroplasty following the high-intensity physiotherapy program, including the perceived recovery level at discharge, and reasons for (not) adhering to the given advice at discharge (being either continuing with or refraining from further physiotherapy treatment).Design: A mixed-methods approach: semi-structured interviews were held and were then used to develop items and answer categories for a survey.Methods: Fifteen patients participated in semi-structured interviews, which focused on expectations and experiences related to the total knee arthroplasty and physiotherapy program, the perceived recovery level at the moment of discharge, and the reasons for the advice at discharge (continuing with or refraining from physiotherapy treatment) being followed. A deductive thematic analysis of those interviews was used to develop a survey, which was sent to the total cohort of 60 patients. Logistic regression models were estimated to determine which factors were associated with the continuation of physiotherapy treatment and (not) following the advice. Results: Four themes were identified: (1) confidence of independent recovery; (2) experiencing residual complaints; (3) expecting further improvement of physical fitness; and (4) preferring to be supervised by a healthcare professional. These themes were covered by 14 items in the survey. In total, 55 out of 60 patients completed the survey. Out of 36 patients, 23 continued with physiotherapy treatment despite an adequate level of recovery. Five out of 19 patients, who were advised to continue with physiotherapy treatment, decided to refrain. Advice to continue with physiotherapy treatment was followed more often than advice to refrain from physiotherapy treatment (OR 0.09; 95%CI 0.01-0.85). Reasons for continuing with physiotherapy treatment were residual complaints, the expectation that their physical fitness could be improved and preferring to be supervised by a healthcare professional. In contrast, patients who refrained from physiotherapy, despite being advised to continue, were self-confident that they could do exercises by themselves.Conclusions: A substantial proportion of patients continued with physiotherapy treatment because they expected that a higher level of recovery could be reached. The level of self-confidence to recover on their own seemed to be an important factor in deciding to continue with or refrain from physiotherapy treatment. It would be helpful to focus on self-management skills during the high-intensity physiotherapy program following total knee arthroplasty.

Regional Anesthesia and Readmission Rates After Total Knee Arthroplasty

BACKGROUND

Total knee arthroplasty is a commonly performed procedure and an important contributor to national health care spending. Reducing the incidence of readmission could have important consequences for patient well-being and relevant financial implications. Whether regional anesthesia techniques are associated with decreased readmission rates and costs among privately insured patients remains unknown.

METHODS

Using administrative claims data, we identified 138,362 privately insured patients 18-64 years of age who underwent total knee arthroplasty between 2002 and 2013. We then examined whether the use of a nerve block was associated with decreases in readmission rates and related costs during the 90 days after discharge. Our analyses were adjusted for potential confounding variables including medical comorbidities and previous use of opioids and other medications.

RESULTS

After adjusting for patient demographics, comorbidities, and preoperative medication use, the adjusted 90-day readmission rate was 1.8% (95% confidence interval [CI], 1.1-2.4) among patients who did not receive a block compared to 1.7% (95% CI, 1.1-2.4) among patients who did (odds ratio, 0.99; 95% CI, 0.91-1.09; P = .85). The adjusted readmission-related postoperative cost for patients who did not receive a block was $561 (95% CI, 502-619) and $574 (95% CI, 508-639) for patients who did (difference, $13; 95% CI, -75 to 102; P = .74). This lack of statistically significant differences held for subgroup and sensitivity analyses.

CONCLUSIONS

Nerve blocks were not associated with improved measures of long-term postoperative resource use in this younger, privately insured study population.

The Role of Crosslinked Polyethylene in Reducing Aggregated Costs of Total Hip Arthroplasty in the United States

BACKGROUND

Widespread adoption of crosslinked polyethylene for the acetabular articular surface for total hip arthroplasty has substantially reduced revision rates and dislocation rates. We aim to provide estimates of the resulting magnitude of the annual reduction in aggregated costs of total hip arthroplasty surgery in the United States.

METHODS

After we obtained, from the literature, the contrasting mid-term rates of revisions and dislocations of total hip arthroplasty using conventional polyethylene vs those using crosslinked polyethylene, specifically from only registry studies and prospective, randomized controlled studies, we multiplied these incidence figures by the cost estimates of these failures to generate approximations of the cost savings in the United States from the use of crosslinked polyethylene.

RESULTS

The estimates suggest that in the United States these savings might be one billion dollars per annual cohort over a 15-year duration.

CONCLUSION

The use of crosslinked polyethylene has reduced substantially the overall costs of total hip arthroplasty surgery in the United States.

Preoperative Physical Therapy Results in Shorter Length of Stay and Discharge Disposition Following Total Knee Arthroplasty: A Retrospective Study

Objective

Total knee arthroplasty is an effective surgical approach used to treat arthritis and knee trauma. Its utilization has grown, as has the accompanying financial impact, resulting in an equal need to advance physical therapy practice. One emerging approach improving patient outcomes and reducing cost is the inclusion of a preoperative physical therapy visit. The aim of this study was to quantify the economic impact of a standardized preoperative physical therapy visit in the healthcare setting.

Design

This study is a retrospective review of 1,043 adult patients who underwent total knee arthroplasty.

Methods

Patients who underwent total knee arthroplasty were divided into those who received a prehab compared with those who did not.

Results

Preoperative physical therapy resulted in a marked decrease in length of stay, with 37.1% of preoperative physical therapy patients leaving inpatient care on post-operative day 1 compared to 27.0% of the no preoperative physical therapy controls (p < 0.001). Preoperative physical therapy also improved discharge disposition, with 41.6% of preoperative physical therapy patients returning home and utilizing outpatient services compared to 23.2% of controls (p < 0.001). No effect on duration of care was observed.

Conclusion

These data suggest that a single pre-operative physical therapy visit improves key outcomes, both clinically and financially, following total knee arthroplasty.

Risk Adjustment Is Necessary in Value-Based Payment Models for Arthroplasty for Oncology Patients

BACKGROUND

Value-based payment models such as bundled payments have been introduced to reduce costs following total hip arthroplasty (THA). Concerns exist, however, about access to care for patients who utilize more resources. The purpose of this study is thus to compare resource utilization and outcomes of patients undergoing THA for malignancy with those undergoing THA for fracture or osteoarthritis.

METHODS

We queried the American College of Surgeons National Surgical Quality Improvement Program database to identify all hip arthroplasties performed from 2013 to 2016 for a primary diagnosis of malignancy (n = 296), osteoarthritis (n = 96,480), and fracture (n = 13,406). The rates of readmissions, reoperations, comorbidities, mortality, and surgical characteristics were compared between the 3 cohorts. To control for confounding variables, a multivariate analysis was performed to identify independent risk factors for resource utilization and outcomes following THA.

RESULTS

Patients undergoing THA for malignancy had a longer mean operative time (155.7 vs 82.9 vs 91.0 minutes, P < .001), longer length of stay (9.0 vs 7.2 vs 2.6 days, P < .001), and were more likely to be discharged to a rehabilitation facility (42.1% vs 61.8% vs 20.2%, P < .001) than patients with fracture or osteoarthritis. When controlling for demographics and comorbidities, patients undergoing THA for malignancy had a higher rate of readmission (adjusted odds ratio 3.39, P < .001) and reoperation (adjusted odds ratio 3.71, P < .001).

CONCLUSION

Patients undergoing THA for malignancy utilize more resources in an episode-of-care and have worse outcomes. Risk adjustment is necessary for oncology patients in order to prevent access to care problems for these high-risk patients.

Risk factors associated with cardiac complication after total joint arthroplasty of the hip and knee: a systematic review

Background

Cardiac complication represents a major cause of morbidity and mortality after total joint arthroplasty, thus necessitating investigation into the associated risks in total hip arthroplasty and total knee arthroplasty. There remains a lack of clarity for many risk factors in the current literature. The aim of this systematic review is to assess the most recent published literature and identify the risk factors associated with cardiac complication in total hip arthroplasty and total knee arthroplasty.

Methods

Scopus, PubMed, CINHAL, and Cochrane were searched to identify studies published since 2008 reporting on risk factors associated with cardiac complication in elective primary in total hip arthroplasty and total knee arthroplasty in patients ≥18 years old with osteoarthritis. Reported odds ratios, hazard ratios, and relative risk were the principal summary measures collected. The included studies were too heterogeneous to enable meta-analysis.

Results

Fifteen studies were included in this systematic review. Increasing age and history of cardiac disease were found by most studies to be positively associated with risk of cardiac complication. There was no strong association found between obesity and cardiac complication. The evidence for other risk factors was less clear in the examined literature, although there is suggestive evidence for male gender and cerebrovascular disease increasing risk.

Conclusions

Increasing age and history of cardiac disease increases the risk of cardiac complication after total hip arthroplasty and total knee arthroplasty. Other risk factors commonly attributed to increased risk in non-cardiac surgery including hypertension and obesity require further evaluation in arthroplasty.

Systematic review registration

A detailed protocol was published in the PROSPERO database (registration number CRD42018095887) for this systematic review.

Electronic supplementary material

The online version of this article (10.1186/s13018-018-1058-9) contains supplementary material, which is available to authorized users.

A predominant Th1 polarization is present in synovial fluid of end-stage osteoarthritic knee joints: analysis of peripheral blood, synovial fluid and synovial membrane

Thorough understanding of the complex pathophysiology of osteoarthritis (OA) is necessary in order to open new avenues for treatment. The aim of this study was to characterize the CD4⁺ T cell population and evaluate their activation and polarization status in OA joints. Fifty-five patients with end-stage knee OA (Kellgren-Lawrence grades III-IV) who underwent surgery for total knee arthroplasty (TKA) were enrolled into this study. Matched samples of synovial membrane (SM), synovial fluid (SF) and peripheral blood (PB) were analysed for CD3⁺ CD4⁺ CD8^- T cell subsets [T helper type 1 (Th1), Th2, Th17, regulatory T cells] and activation status (CD25, CD69, CD45RO, CD45RA, CD62L) by flow cytometry. Subset-specific cytokines were analysed by cytometric bead array (CBA). SM and SF samples showed a distinct infiltration pattern of CD4⁺ T cells. In comparison to PB, a higher amount of joint-derived T cells was polarized into CD3⁺ CD4⁺ CD8^- T cell subsets, with the most significant increase for proinflammatory Th1 cells in SF. CBA analysis revealed significantly increased immunomodulating cytokines [interferon (IFN)-γ, interleukin (IL)-2 and IL-10] in SF compared to PB. Whereas in PB only a small proportion of CD4⁺ T cells were activated, the majority of joint-derived CD4⁺ T cells can be characterized as activated effector memory cells (CD69⁺ CD45RO⁺ CD62L^- ). End-stage OA knees are characterized by an increased CD4⁺ T cell polarization towards activated Th1 cells and cytokine secretion compared to PB. This local inflammation may contribute to disease aggravation and eventually perpetuate the disease process.

Hip replacement

Total hip replacement is a frequently done and highly successful surgical intervention. The procedure is undertaken to relieve pain and improve function in individuals with advanced arthritis of the hip joint. Symptomatic osteoarthritis is the most common indication for surgery. In paper 1 of this Series, we focus on how patient factors should inform the surgical decision-making process. Substantial demands are placed upon modern implants, because patients expect to remain active for longer. We discuss the advances made in implant performance and the developments in perioperative practice that have reduced complications. Assessment of surgery outcomes should include patient-reported outcome measures and implant survival rates that are based on data from joint replacement registries. The high-profile failure of some widely used metal-on-metal prostheses has shown the shortcomings of the existing regulatory framework. We consider how proposed changes to the regulatory framework could influence safety.

Revision Surgery in Total Joint Replacement Is Cost-Intensive

Revisions after total joint replacement increase constantly. In the current study, we analyzed clinical outcome, complication rates, and cost-effectiveness of revision arthroplasty. In a retrospective analysis of 162 revision hip and knee arthroplasties from our institutional joint registry responder rate, patient-reported outcome measures (EQ-5D, WOMAC), complication rates, and patient-individual charges in relation to reimbursement were compared with a matched control group of primary total joint replacements. Positive responder rate one year postoperatively was lower for revision arthroplasties with 72.9% than for primary arthroplasties with 90.1% (OR=0.30, 95%CI=0.18-0.59, p=0.001). Correspondingly, improvement in patient-reported outcome measures one year after surgery was lower in revision than in primary joint arthroplasty with EQ-5D 0.19±0.25 to 0.30±0.24 (p<0.001) and WOMAC 24.3±30.3 to 41.2±21.3 (p<0.001). Infection rate was higher in revision (6.8%) compared to primary replacements (0%, p=0.001). Mean charges in revision arthroplasty were 76.0% higher than in matched primary joint replacements (7110.8±2249.4$ to 4041.1±975.7$, p<0.001), whereas reimbursement was only 23.6% higher (9243.3±2258.4$ in revision and 7477.9±703.1$ in primary arthroplasty, p<0.001). Revision arthroplasty is associated with lower outcome and higher infection rate compared to primary replacements. The high financial expense of revision arthroplasty is only partly covered by a higher reimbursement.

Hypothyroidism Increases 90-Day Complications and Costs Following Primary Total Knee Arthroplasty

BACKGROUND

Thyroid disease is common and often remains undetected in the US population. Thyroid hormone has an array of metabolic, immunologic, and musculoskeletal functions crucial to well-being. The influence of thyroid disease on perioperative outcomes following primary total knee arthroplasty (TKA) is poorly understood. We hypothesized that hypothyroidism was associated with a higher risk of postoperative complications and 90-day costs following primary TKA.

METHODS

The Medicare standard analytical files were queried using International Classification of Disease codes between 2005 and 2014 to identify patients undergoing primary TKA. Patients with a diagnosis of hypothyroidism were matched by age and gender on a 1:1 ratio. Ninety-day postoperative complication rates, day of surgery, and 90-day global period charges and reimbursements were compared between matched cohorts.

RESULTS

A total of 2,369,594 primary TKAs were identified between 2005 and 2014. After age and gender matching, each cohort consisted of 98,555 patients. Hypothyroidism was associated with greater odds of postoperative complications compared to matched controls (odds ratio 1.367, 95% confidence interval 1.322-1.413). The 90-day incidence of multiple postoperative medical and surgical complications, including periprosthetic joint infection, was higher among patients with hypothyroidism. Day of surgery and 90-day episode of care costs were significantly higher in the hypothyroidism cohort.

CONCLUSION

This study demonstrated an increased risk of multiple postoperative complications and higher costs among patients with hypothyroidism following primary TKA. Surgeons should counsel patients on these findings and seek preoperative optimization strategies to reduce these risks and lower costs in this patient population.

Utilization and Short-Term Outcomes of Primary Total Hip and Knee Arthroplasty in the United States and Canada: An Analysis of New York and Ontario Administrative Data

OBJECTIVE

Total knee arthroplasty (TKA) and total hip arthroplasty (THA) are common and effective surgical procedures. This study sought to compare utilization and short-term outcomes of primary TKA and THA in adjacent regions of Canada and the United States.

METHODS

The study was designed as a retrospective cohort study of patients who underwent primary TKA or THA, comparing administrative data from New York and Ontario in 2012-2013. Demographic features of the TKA and THA patients, per capita utilization rates, and short-term outcomes were compared between the jurisdictions.

RESULTS

A higher percentage of New York hospitals performed TKA compared to Ontario hospitals (75.7% versus 42.1%; P < 0.001), and the mean annual procedural volume for TKAs was lower in New York hospitals (mean 179 versus 327 in Ontario hospitals; P < 0.001). After direct standardization, utilization was significantly lower in New York compared to Ontario, both for TKA (16.1 TKAs versus 21.4 TKAs per 10,000 population per year; P < 0.001) and for THA (10.5 THAs versus 11.5 THAs per 10,000 population per year; P < 0.001). For those who underwent TKA, the length of stay in Ontario hospitals was significantly longer (mean 3.7 days versus 3.4 days in New York hospitals; P < 0.001). A smaller percentage of New York patients were discharged directly home (46.2% versus 90.9% of Ontario patients; P < 0.001), but 30-day and 90-day readmission rates were higher in New York compared to Ontario (30-day rates, 4.6% versus 3.9% [P < 0.001]; 90-day rates, 8.4% versus 6.7% [P < 0.001]). For the THA cohorts, the results with regard to length of stay, discharge disposition, and readmission rates were similar to those for TKA.

CONCLUSION

Ontario has higher utilization of total joint arthroplasty than New York but has a smaller percentage of hospitals performing these procedures. Patients are more likely to be discharged home and less likely to be readmitted in Ontario. Our results suggest areas where each jurisdiction could improve.

Predictors of Outcome After Primary Total Joint Replacement

BACKGROUND

Total hip and knee replacements are frequently performed curative treatment options in end-stage arthritis. In this study, we analyzed clinical outcome, complications, and predictors of outcome in modern joint replacement.

METHODS

In a retrospective analysis of over 2000 primary total hip and knee replacements from our institutional joint registry, responder rates for positive outcome as defined by the OMERACT-OARSI criteria, postoperative complication rates, and patient-reported outcome measures (EQ-5D, WOMAC) within the first year were compared between hip and knee replacements. Furthermore, preoperative risk factors associated with nonresponder rate were evaluated.

RESULTS

Positive responder rate was higher for hip replacements with 92.8% (1145/1234) than for knee replacements with 86.1% (839/975, P < .001). Infection rates were lower (P = .04), whereas intraoperative fracture occurred more frequently (P = .001) in hip than in knee replacements. Patient-reported outcome measures 1 year after surgery were higher in hip than in knee replacements with EQ-5D (0.88 ± 0.17 to 0.81 ± 0.19, P < .001) and WOMAC (84.58 ± 16.73 to 74.31 ± 18.94, P < .001). Besides the type of joint replacement (hazard ratio [HR] 2.0, P < .001), high preoperative outcome measures (HR 7.4, P < .001) and male gender (HR 1.4, P = .05) were independent risk factors of nonresponders after joint replacement.

CONCLUSION

Both total hip and knee replacements are safe procedures with low complication rates. Still, postoperative outcome is higher in hip than in knee arthroplasty. High preoperative clinical scores are a risk factor for poor clinical improvement following total joint replacement and can be used in counseling patients in the office.

Disease burden of knee osteoarthritis patients with a joint replacement compared to matched controls: a population-based analysis of a Dutch medical claims database

OBJECTIVE

On a population level, the incidence of knee prostheses (KPs) has increased, but excess health care costs per patient, compared to matched controls without a KP, in the years surrounding these procedures and their determinants are largely unknown. We therefore aimed to provide estimates of age- and sex-specific incidence of KPs, revision KPs, and prosthesis complications in patients with knee osteoarthritis (OA) and to determine excess health care costs in the years surrounding surgery compared with matched controls.

METHODS

All KPs in OA patients in the Achmea Health Database were identified as well as up to four controls. Incidence rates of KPs, revisions, and complications from 2006 to 2013 were determined. Annual health care cost and excess costs (over matched controls) preceding, during, and after surgery were calculated and their determinants were evaluated.

RESULTS

The increased incidence of KPs, revisions, and complications was strongest in younger age categories and men. The average costs per patient were relatively stable between 2006 and 2012. KP patient's annual health care costs increased towards the year of surgery. After surgery, costs decreased, but remained higher as compared to costs prior to surgery. High post-surgery costs were mainly associated with subsequent revisions or additional KPs, but costs were also higher in females, lower age categories, and lower social economic status.

CONCLUSION

These results underscore the increasing burden and medical need associated with end-stage OA, especially in younger age categories. Improvement of guidelines tailored to individual patient groups aimed at avoiding complications and revisions is required to counteract this increasing burden.

The Impact of Discharge Disposition on Episode-of-Care Reimbursement After Primary Total Hip Arthroplasty

BACKGROUND

Total joint arthroplasty (TJA) accounts for more Medicare expenditure than any other inpatient procedure. The Comprehensive Care for Joint Replacement model was introduced to decrease cost and improve quality in TJA. The largest portion of episode-of-care costs occurs after discharge. This study sought to quantify the cost variation of primary total hip arthroplasty (THA) according to discharge disposition.

METHODS

The Medicare and Humana claims databases were used to extract charges and reimbursements to compare day-of-surgery and 91-day postoperative costs simulating episode-of-care reimbursements. Of the patients who underwent primary THA, 257,120 were identified (204,912 from Medicare and 52,208 from Humana). Patients were stratified by discharge disposition: home with home health, skilled nursing facility, or inpatient rehabilitation facility.

RESULTS

There is a significant difference in the episode-of-care costs according to discharge disposition, with discharge to an inpatient rehabilitation facility the most costly and discharge to home the least costly.

CONCLUSION

Postdischarge costs represent a sizeable portion of the overall expense in THA, and optimizing patients to allow safe discharge to home may help reduce the cost of THA.

Bundled Payments in Total Joint Replacement: Keeping Our Care Affordable and High in Quality

PURPOSE OF REVIEW

The purpose of this review was to evaluate the literature regarding bundle payment reimbursement models for total joint arthroplasty (TJA).

RECENT FINDINGS

From an economic standpoint, TJA are cost-effective, but they represent a substantial expense to the Centers for Medicare & Medicaid Services (CMS). Historically, fee-for-service payment models resulted in highly variable cost and quality. CMS introduced Bundled Payments for Care Improvement (BPCI) in 2012 and subsequently the Comprehensive Care for Joint Replacement (CJR) reimbursement model in 2016 to improve the value of TJA from the perspectives of both CMS and patients, by improving quality via cost control. Early results of bundled payments are promising, but preserving access to care for patients with high comorbidity burdens and those requiring more complex care is a lingering concern. Hospitals, regardless of current participation in bundled payments, should develop care pathways for TJA to maximize efficiency and patient safety.

Distribution and Drivers of Average Direct Cost of Osteoarthritis in Canada From 2003 to 2010

OBJECTIVE

To estimate the distribution and drivers of the average direct cost of osteoarthritis (OA) in Canada using a population-based health microsimulation model of OA from 2003 to 2010.

METHODS

We used a previously published microsimulation model to estimate the distribution of average cost of OA across different cost components and OA stages. OA stages were defined according to the patient flow within the health care system. Cost components associated with pharmacologic and nonpharmacologic treatments, physician visits, and hospitalization were included. Scenario analysis was performed to evaluate average cost drivers from 2003 to 2010.

RESULTS

During the study period, the OA population size grew from 2.9 to 3.6 million, while the average cost increased from $577 to $811 (Canadian) per patient per year. The highest increase in share of cost components was for total joint replacement (TJR) surgery (24% to 32%). The highest average cost was incurred by patients in stage 4 (during and after revision surgery), while around 80% of OA patients were in stage 1 (OA diagnosed but has not visited an orthopedic surgeon). Increase in the proportion of OA patients receiving TJR surgeries (34%) and price inflation (29%) were the most significant drivers of average cost.

CONCLUSION

The average cost of OA has been increasing during the study period mostly due to an increase in the proportion of patients receiving TJR surgeries and price inflation. The distribution of average cost of OA across disease stages needs to be considered when designing policies targeting specific aspects of OA care.

The Effect of Comorbidities on Discharge Disposition and Readmission for Total Joint Arthroplasty Patients

BACKGROUND

As the annual demand and number of total joint arthroplasty cases increase, so do concerns of outcomes of patient with specific comorbidities relative to outcomes and costs of care.

METHODS

The study cohort included 2009 primary total knee arthroplasty (TKA) patients and 905 total hip arthroplasty patients. Discharge disposition was classified as discharge to any facility or home. The comorbidities of the patients who were readmitted and those without a 90-day event were also evaluated.

RESULTS

In the TKA population, age, female gender, nonsmoking status, venous thromboembolism (VTE) history, and diabetes were significantly associated with discharge to extended care facility (ECF) on univariate analysis, unlike body mass index. With multivariate analyses, female gender, age, VTE history, and diabetes were associated with ECF placement, but smoking was not. In the total hip arthroplasty population, age, female gender, and nonsmoking status were significantly associated with discharge to ECF on univariate analysis, whereas body mass index, diabetes, and VTE history were not. On multivariate analyses, female gender and age were associated with ECF, but smoking was not. The only significant finding for the readmission data was an increased rate of readmission for TKA patients of older age.

CONCLUSION

The potential of projecting patient discharge and readmission allows physicians to counsel patients and improve patient expectations.

Patients With High Mental Health Costs Incur Over 30 Percent More Costs Than Other High-Cost Patients

A small proportion of health care users, called high-cost patients, account for a disproportionately large share of health care costs. Most literature on these patients has focused on the entire population. However, high-cost patients whose use of mental health care services is substantial are likely to differ from other members of the population. We defined a mental health high-cost patient as someone for whom mental health-related services accounted for at least 50 percent of total health care costs. We examined these patients' health care utilization and costs in Ontario, Canada. We found that their average cost for health care, in 2012 Canadian dollars, was $31,611. In contrast, the cost was $23,681 for other high-cost patients. Mental health high-cost patients were younger, lived in poorer neighborhoods, and had different health care utilization patterns, compared to other high-cost patients. These findings should be considered when implementing policies or interventions to address quality of care for mental health patients so as to ensure that mental health high-cost patients receive appropriate care in a cost-effective manner. Furthermore, efforts to manage mental health patients' health care use should address their complex profile through integrated multidisciplinary health care delivery.

Myocardial Infarction Risk in Arthroplasty vs Arthroscopy: How Much Does Procedure Type Matter?

BACKGROUND

This study aimed at assessing short-term risk of serious cardiac events after elective total joint arthroplasty (TJA) as compared to a less-invasive procedure, knee arthroscopy (KA).

METHODS

Patients who underwent elective primary total hip arthroplasty (THA), total knee arthroplasty (TKA), or KA from 2011 to 2014 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. A 1:1 propensity matching was used to generate 2 control cohorts of KA patients with similar characteristics. Bivariate and multivariate analyses were assessed using perioperative variables.

RESULTS

A total of 24,203 THA, 21,740 TKA, and 45,943 KA patients were included. Bivariate analysis revealed significantly higher rates of serious 30-day cardiac events (myocardial infarction or cardiac arrest) among THA (0.15% vs 0.05%, P < .001) and TKA patients (0.14% vs 0.05%, P < .03) vs KA controls. In multivariate analysis controlling for patient characteristics and comorbidities, THA and TKA were associated with a 2.61 and 1.98 times odds of serious 30-day cardiac events as compared to controls (P ≤ .03 for both). Additional independent predictors of serious 30-day cardiac events included age, smoking, cardiac disease, and American Society of Anesthesiologists class 3/4. In the THA and TKA cohorts, serious cardiac events occurred within the first 3 days postoperation compared to 4 days in controls.

CONCLUSION

After controlling for patient characteristics and comorbidities, TJA increased the short-term risk of serious cardiac event compared to a less-invasive procedure. This information better quantifies the risk differential for patients considering surgery as they engage in shared decision making with their providers. In addition, our data may have an impact on perioperative management of antithrombotic medications used in patients with cardiac disease. The median time in days to serious cardiac event was 2 in THA and 3 in TKA vs 4 in KA, which may have implications in postoperative monitoring of patients after surgery.

Factors Associated With Referral to Secondary Care in Patients With Osteoarthritis of the Hip or Knee After Implementation of a Stepped-Care Strategy

OBJECTIVE

We introduced a stepped-care strategy (SCS) for hip and knee osteoarthritis, focusing on delivery of high-quality stepped care. In this study, we aimed to identify factors associated with various steps of the SCS.

METHODS

We used data from a 2-year observational prospective cohort study, including 313 patients visiting their general practitioner (GP) with a new episode of hip/knee osteoarthritis. We used logistic multilevel analyses to identify factors at the level of the patient, the GP, and the general practice, related to treatment limited to primary care, referral to nonsurgical secondary care, or surgical procedures.

RESULTS

Patients whose treatment had been limited to primary care tended to function physically better (odds ratio [OR] 1.03). Furthermore, they less often received exercise therapy (OR 0.46), intraarticular injections (OR 0.08), and radiologic assessments (OR 0.06). Continuation of nonsurgical care after referral was more likely in employed patients (OR 2.90) and patients who had no exercise therapy (OR 0.19) or nonsteroidal antiinflammatory drugs (OR 0.35). Surgically treated patients more often received exercise therapy (OR 7.42). Referral and surgical treatment depended only to a limited extent on the GP or the general practice.

CONCLUSION

After implementation of the SCS in primary care, the performance of exercise therapy, rather than disease severity or psychologic factors, seems to play a key role in the decision whether or not to refer for surgical or nonsurgical treatment in secondary care. To optimize patient-tailored treatment, future research should be adressed to determine the optimal moment of switching from primary to secondary care in patients with hip/knee osteoarthritis.

Preoperative Interventions and Charges Before Total Knee Arthroplasty

BACKGROUND

The cost effectiveness of total knee arthroplasty (TKA) has been well established, but little data exist regarding preoperative interventions and their costs. The purpose of this study was to examine preoperative interventions and their associated charges within the 2-year period before TKA.

METHODS

A retrospective cohort analysis of patients undergoing TKA between 2007 and 2011 was conducted using the PearlDiver Patient Record Database. Patients' inpatient and outpatient billing records were tracked over the 2-year period before receiving a TKA.

RESULTS

A total of 35,596 patients from Medicare and 47,064 from United Healthcare underwent TKA from 2009 to 2011. In the 2-year period before TKA, the per patient average charge was $3545.82 for Medicare and $3281.57 for United Healthcare. In the 2-year period before TKA, 21.4% (Medicare) and 23.3% (United Healthcare) of all patients received a magnetic resonance imaging, with between 31.9% (Medicare) and 45.6% (United Healthcare) of these occurring within 3 months of surgery (P < .05). During this same period, 49.4% (Medicare) and 63.2% (United Healthcare) of all patients received an intra-articular injection, with between 29.4% (Medicare) and 44.8% (United Healthcare) of these occurring within 3 months of surgery (P < .05).

CONCLUSION

Interventions and costs before TKA occur largely within 6 months preoperatively, with a substantial portion occurring within 3 months. These interventions may not be clinically or cost effective for certain patients, such as those with moderate-to-severe osteoarthritis. Foregoing these interventions and opting to perform TKA earlier may reduce costs and prevent unnecessary tests and procedures.

Patient Perception of Value in Bundled Payments for Total Joint Arthroplasty

BACKGROUND

A central concern for providers in a bundled payment model is determining how the bundle is distributed. Prior studies have shown that current reimbursement rates are often not aligned with patients' values. While willingness-to-pay (WTP) surveys are perhaps useful in a fee-for-service arrangement to determine overall reimbursement, the percentage of payment distribution might be as or more important in a bundled payment model.

METHODS

All patients undergoing primary total joint arthroplasty by a single surgeon were offered participation in a preoperative WTP survey. At a minimum 3 months postoperatively, patients were mailed instructions for an online follow-up survey asking how they would allocate a hypothetical bonus payment.

RESULTS

From January through December 2014, 45 patients agreed to participate in the preoperative WTP survey. Twenty patients who were minimum 3 months postoperative also completed the follow-up survey. Patients valued total knee and hip arthroplasty at $28,438 (95% confidence interval [CI]: $20,551-36,324) and $39,479 (95% CI: $27,848-$51,112), respectively. At 3 months postoperatively, patients distributed a hypothetical bonus payment 55.5% to the surgeon (95% CI: 47.8%-63.1%), 38% to the hospital (95% CI: 30.3%-45.7%), and 6.5% (95% CI: -1.2% to 14.2%) to the implant manufacturer (P < .001).

CONCLUSION

The data suggest that total joint arthroplasty patients have vastly different perceptions of payment distributions than what actually exists. In contrast to the findings of this study, the true distribution of payments for an episode of care averages 65% to the hospital, 27% to the implant manufacturer, and 8% to the surgeon. While many drivers of payment distribution exist, this study suggests that patients would allocate a larger proportion of a bundled payment to surgeons than is currently disbursed. This finding may also provide a plausible explanation for patients' consistent overestimation of surgeon reimbursements.

Allergy to Surgical Implants

Surgical implants have a wide array of therapeutic uses, most commonly in joint replacements, but also in repair of pes excavatum and spinal disorders, in cardiac devices (stents, patches, pacers, valves), in gynecological implants, and in dentistry. Many of the metals used are immunologically active, as are the methacrylates and epoxies used in conjunction with several of these devices. Allergic responses to surgical components can present atypically as failure of the device, with nonspecific symptoms of localized pain, swelling, warmth, loosening, instability, itching, or burning; localized rash is infrequent. Identification of the specific metal and cement components used in a particular implant can be difficult, but is crucial to guide testing and interpretation of results. Nickel, cobalt, and chromium remain the most common metals implicated in implant failure due to metal sensitization; methacrylate-based cements are also important contributors. This review will provide a guide on how to assess and interpret the clinical history, identify the components used in surgery, test for sensitization, and provide advice on possible solutions. Data on the pathways of metal-induced immune stimulation are included. In this setting, the allergist, the dermatologist, or both have the potential to significantly improve surgical outcomes and patient care.

How outcome prediction could affect patient decision making in knee replacements: a qualitative study

Background

There is approximately a 17 % dissatisfaction rate with knee replacements. Calls for tools that can pre-operatively identify patients at risk of being dissatisfied have been widespread. However, it is not known how to present such information to patients, how it would affect their decision making process, and at what part of the pathway such a tool should be used.

Methods

Using focus groups involving 12 participants and in-depth interviews with 10 participants, we examined how individual predictions of outcome could affect patients’ decision making by providing fictitious predictions to patients at different stages of treatment. A thematic analysis was used to analyse the data.

Results

Our results demonstrate several interesting findings. Firstly, patients who have received information from friends and family are unwilling to adjust their expectation of outcome down (i.e. to a worse outcome), but highly willing to adjust it up (to a better outcome). This is an example of the optimism bias, and suggests that the effect on expectation of a poor outcome prediction would be blunted. Secondly, patients generally wanted a “bottom line” outcome, rather than lots of detail. Thirdly, patients who were earlier in their treatment for osteoarthritis were more likely to find the information useful, and it was more likely to affect their decision, than patients later in their treatment pathway.

Conclusion

This research suggest that an outcome prediction tool would have most effect targeted towards people at the start of their treatment pathway, with a “bottom line” prediction of outcome. However, any effect on expectation and decision making of a poor outcome prediction is likely to be blunted by the optimism bias. These findings merit replication in a larger sample size.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1165-x) contains supplementary material, which is available to authorized users.