Determining Cost-Effectiveness of Total Hip and Knee Arthroplasty Using the Short Form-6D Utility Measure

doi:10.1016/j.arth.2016.08.006

The Journal of Arthroplasty

Volume 32, Issue 2, February 2017, Pages 351-354

https://doi.org/10.1016/j.arth.2016.08.006 Get rights and content

Abstract

Background

With the implementation of the Patient Protection and Affordable Care Act, cost-effectiveness analyses are becoming increasingly important for resource allocation, and particularly for the justification of costly procedures, such as total knee and total hip arthroplasties (TKAs and THAs). Therefore, using the Short Form-6D (SF-6D) utility values, the purpose of this study was to determine (1) the quality-adjusted life years (QALYs) gained and (2) and the cost-effectiveness of undergoing THA and TKA.

Methods

A total of 844 patients (357 men, 487 women) who had a mean age of 65 years (range, 39 to 80 years) underwent primary TKA, and 224 patients who had a mean age of 69 years (range, 44 to 88 years) underwent primary THAs at 7 institutions. The SF-6D values were derived for each patient preoperatively and at 1-year follow-up. QALYs were estimated at 1 year, and lifetime QALYs gained were determined using predicted life-expectancy values, at a discounted rate of 3% per year of life expectancy, to reflect a diminishing gain with time. National-level costs were determined using the 2011 Nationwide Inpatient Sample, and incremental cost-effectiveness ratios (ICER) were deduced for both groups.

Results

The preoperative SF-6D values for the THA and TKA cohorts were 0.614 (range, 0.37 to 1) and 0.62 (range, 0.3 to 0.93). Postoperatively, SF-6D values improved significantly at 1 year in both groups. One-year QALYs for TKA and THA were 0.768 and 0.799. Lifetime QALYs gained for the groups were 2.07 and 1.85 (1.39 and 1.34 if discounted at a rate of 3% per year). The estimated ICER for TKA vs baseline presurgery was $43,107 per QALY, and $39,453 per QALY for THA vs baseline presurgery.

Conclusion

The ICER showed that THA and TKA are cost-effective, compared to the $50,000 USD/QALY threshold for cost-effectiveness, and justify resources allocated to these surgeries. The SF-6D can utilize existing functional outcome data, which makes these cost calculations considerably easier and more feasible for practicing orthopedists.

Section snippets

Methods

We prospectively evaluated 844 patients (357 men, 487 women) who had a mean age of 65 years (range, 39 to 80) and a mean body mass index (BMI) of 30.6 kg/m² (range, 17.7 to 40) who underwent primary TKA and 224 patients who had a mean age of 69 years (range, 44 to 88) and mean BMI of 28.8 kg/m² (range, 19.8 to 38.9) who underwent primary THAs at 7 institutions. This cohort of patients underwent primary THA or TKA at 7 different institutions, and they were recruited for a longitudinal postmarket

Results

The preoperative SF-6D values for the THA and TKA cohorts were 0.614 and 0.62. Postoperatively, there were significant improvements in the values at all time points compared to preoperatively. The SF-6D values at 1 year in the THA and TKA groups were 0.799 and 0.768 (P < .0001; see Tables 1 and 2). Differences between postoperative scores at each of the time points were not statistically significant, suggesting that the health gains were maintained from 6-month follow-up onward throughout the

Discussion

TKA and THA are highly efficacious at improving function and reducing pain; however, with the implementation of the Patient Protection and Affordable Care Act, cost-effectiveness analyses become increasingly important for resource allocation and justification of the costs of undergoing these procedures. Multiple utility values have been developed, but the SF-6D is advantageous as it allows clinicians to retrospectively perform cost-utility analyses and deduce cost-effectiveness from existing

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Prior Authorization in Total Joint Arthroplasty: A Survey of the American Association of Hip and Knee Surgeons Membership
2023, Journal of Arthroplasty
This study surveyed the impact that prior authorization has on the practices of total joint arthroplasty (TJA) members of the American Association of Hip and Knee Surgeons (AAHKS).
A 24-question survey was approved by the AAHKS Advocacy Committee and distributed to all 2,802 board-certified members of AAHKS.
There were 353 survey responses (13%). Ninety-five percent of surgeons noted a 5-year increase in prior authorization. A majority (71%) of practices employ at least 1 staff member to exclusively work on prior authorization. Average time spent on prior authorization was 15 h/wk (range, 1 to 125) and average number of claims peer week was 18 (range, 1 to 250). Surgeries (99%) were the most common denial. These were denied because nonoperative treatment had not been tried (71%) or had not been attempted for enough time (67%). Most (57%) prior authorization processes rarely/never changed the treatment provided. Most (56%) indicated that prior authorization rarely/never followed evidence-based guidelines. A majority (93%) expressed high administrative burden as well as negative clinical outcomes (87%) due to prior authorization including delays to access care (96%) at least sometimes.
Prior authorization has increased in the past 5 years resulting in high administrative burden. Prior authorizations were most common for TJA surgeries because certain nonoperative treatments were not attempted or not attempted for enough time. Surgeons indicated that prior authorization may be detrimental to high-value care and lead to potentially harmful delays in care without ultimately changing the management of the patient.
Outcomes of complex primary total knee arthroplasties performed with custom cutting guides
2021, Knee
Citation Excerpt :
Total knee arthroplasty (TKA) has become one of the most successful and cost-effective healthcare interventions [1–4].
Total knee arthroplasty (TKA) is particularly challenging in patients with marked deformities or existing hardware due to the inability to use traditional instrumentation. One potential technique to mitigate this obstacle is the use of patient-specific cutting guides. The purpose of this study was to evaluate the use of custom cutting guides in complex primary TKAs.
Twenty complex TKAs performed in 18 patients were identified. Of these, 11 were performed in patients with existing hardware, three in patients with dwarfism, three in patients with post-traumatic deformities, two in a patient with multiple epiphyseal dysplasia, and one in a patient with a large deformity from Blount’s disease. All prior hardware was retained. One patient died from unrelated causes three months following surgery. The remaining patients were followed for a mean of 5.2 years (range: 1.2–9.7 years).
One patient sustained a non-displaced, medial tibial plateau fracture intra-operatively that was successfully treated with plating. Mean operative time was 112.1 ± 44.4 min, and mean hospital stay was 2.7 ± 1.6 days. Average deviation from the mechanical axis improved from 10.5° pre-operatively to 3.1° postoperatively (P < 0.001). Average Knee Society Scores improved from 48.1 to 77.4 points (P < 0.001). Mean extension improved from 5.9° to 1.4° (P = 0.049). Two patients subsequently required a manipulation under anesthesia, and one patient had delayed wound healing that resolved without surgery.
Custom cutting guides are a viable option in complex primary TKAs where the use of traditional instrumentation would be challenging.
Modelling the cost-effectiveness of total knee arthroplasty: A systematic review
2020, Journal of Orthopaedics
Osteoarthritis causes a significant healthcare burden and the number of total knee arthroplasty (TKA) procedures is predicted to increase significantly in the coming years. We conducted a systematic review to assess the scope and quality of all current TKA cost-effectiveness analysis (CEA) studies, identify trends, and identify areas for improvement.
An electronic database search of MEDLINE, Embase, the CEA registry and Scopus was used to identify all CEA studies where TKA was used with a comparator. Studies were included from January 1, 1997 to February 2, 2020. The Quality of Health Economic Analysis Studies (QHES) instrument was used to assess their quality. Thirty-three studies were included that offered both a QALY and cost calculation. The main findings, incremental-cost effectiveness ratios and other important study characteristics were then ascertained, and trends identified.
Certain surgical interventions were suggested to be more cost-effective than TKA. This included unicompartmental knee arthroplasty for unicompartmental osteoarthritis, computer-assisted TKA compared to conventional TKA, and resurfacing the patella compared to no resurfacing. TKA was more cost-effective compared to non-operative management regardless of specific patient variables.
The analyses of the CEAs included in the study have to be interpreted with caution. Overall, certain surgical methods within TKA and alternative methods to TKA appear to be favoured for treating particular knee osteoarthritic conditions due to their suggested greater cost-effectiveness but this should be interpreted within local contexts. Our results should help guide future policy-making as healthcare associated costs continue to rise.
How Are We Measuring Cost-Effectiveness in Total Joint Arthroplasty Studies? Systematic Review of the Literature
2020, Journal of Arthroplasty
Citation Excerpt :
Cohort studies can be used for economic evaluation; however, they are subject to several limitations including unclear handling of multiple interventions and questionable credibility of inherent study assumptions [60]. Other studies utilized randomized controlled trial (RCT) study designs [22,24,25]. RCTs have the benefit of minimizing selection bias, but they also fail to incorporate relevant evidence from other studies, have a limited duration of follow-up, and lack abundant comparators [61,62].
As volumes of total hip arthroplasty (THA) and total knee arthroplasty (TKA) continue to rise, it is important to understand their economic impact. No systematic review on cost-effectiveness of THA/TKA has been performed since 2016 despite recent changes in the healthcare environment. The purpose of the study is to provide a contemporary analysis of the cost-effectiveness of total joint arthroplasty and the use of quality-adjusted life years (QALYs).
A systematic review was performed from 2005 to 2020. Online databases (OVID Medline, PubMed, Cost-Effectiveness Analysis Registry, Google Scholar, Elton B. Stephens Co) were queried to identify economic analyses that evaluated the cost-effectiveness of THA/TKA.
In total, 38 studies met the screening criteria. Study designs were primarily Markov models (68%), cohort studies (16%), and randomized trials (8%). Most studies adopted either a societal perspective (45%) or a health system perspective (39%). Analysis revealed that THA/TKA was strongly cost-effective compared to nonsurgical treatment. THA/TKA procedures that were not delayed were more cost-effective than delayed intervention. The majority of studies used QALYs as the primary quality metric (82%); in all these studies there was a significant improvement in QALYs gained.
Given the high economic impact of arthroplasty, ongoing assessment of cost-effectiveness is needed. Twenty-four percent of studies included in this systematic review were published in the last 4 years of this 15-year study period, highlighting the need for continuous assessment of aggregate data. Future studies should incorporate the cost-effectiveness of THA and TKA with respect to the work-value provided by surgeon providers to support health policy and reimbursement.
Implementing a national first-line management program for moderate-severe knee osteoarthritis in Australia: A budget impact analysis focusing on knee replacement avoidance
2020, Osteoarthritis and Cartilage Open
To model potential cost savings associated with implementing a first-line management program for moderate-severe knee osteoarthritis (OA) at a national level in Australia.
A budget impact analysis was undertaken using published trial data and publically available data. Australian population projections and OA prevalence data were used to forecast likely need for total knee replacement (TKR) surgery for 2019–2029. Published data were sourced on TKR avoidance following a 12-week non-surgical knee OA management program (exercise therapy, education, insoles, dietary advice, analgesia) and cost per TKR in Australia. The cost of providing the first-line program was estimated on a sliding scale ($AUD750-$3000), with a base case of $AUD1,500. These inputs were used to model potential annual savings associated with national implementation of the program.
The number of people in Australia with moderate-severe knee OA requiring TKR was estimated to be 56,007 in 2019, rising to 69,038 by 2029. Avoidance of TKR by 34%–68% of people after the first-line management program could translate to savings of $AUD303million-690 million in 2019. Successively lowering the proportion of people who avoided TKR demonstrated that only 1 in 12 program recipients would need to avoid surgery for the program to generate savings.
National implementation of a first-line OA management program as an alternative to TKR could produce substantial cost savings for the Australian healthcare system. Longer term data on TKR avoidance is needed to establish whether cost savings are realised or simply shifted to later years.
The Relationship Between Preoperative Oxford Hip and Knee Score and Change in Health-Related Quality of Life After Total Hip and Total Knee Arthroplasty: Can It Help Inform Rationing Decisions?
2020, Arthroplasty Today
Citation Excerpt :
Our results show that the mean improvement in SF-6D in our patients after both THA (0.27) and TKA (0.22) is well above the MID of 0.041. This is higher than that previously reported [21-23], mainly due to lower preoperative SF-6D in our cohort. The mean EQ-5D(SF-12) score also improved significantly from 0.383 to 0.775 (a gain of 0.392) after THA and from 0.433 to 0.747 (+0.314) after TKA.
In countries with publicly funded health care, there is an increasing need for explicit rationing for total joint arthroplasty (TJA). The Oxford Hip and Knee Scores (OHS/OKS) have been used to set access thresholds for TJA despite not being developed for that purpose. The aim of this study was to determine whether preoperative OHS/OKS can aid rationing decisions by investigating the changes in general health-related quality of life after TJA.
OHS/OKS, Short Form-12, and Short Form-6D (SF-6D) scores were collected preoperatively and at 1 year postoperatively in a cohort of patients undergoing total hip arthroplasty (THA; n = 713) and total knee arthroplasty (TKA; n = 520). The association between preoperative OHS/OKS and postoperative score and the change in OHS/OKS and SF-6D was investigated, adjusting for age and gender.
The mean Oxford scores improved from 13.9 to 40.7 (OHS) and 15.6 to 37.4 (OKS). The mean SF-6D improved after THA (0.53 to 0.80) and TKA (0.56 to 0.78) (all P < .0001). Poorer preoperative Oxford scores were associated with poorer postoperative OHS/OKS and SF-6D but larger improvements. For every 5 points lower preoperative OHS/OKS, the postoperative SF-6D score was worse by a margin of 0.019 (THA) and 0.023 (TKA).
Preoperative OHS/OKS can help inform rationing decisions. A lower preoperative OHS/OKS will result in greater gains but a lower final outcome score in general health-related quality of life.

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: One or more of the authors of this paper have disclosed potential or pertinent conflicts of interest, which may include receipt of payment, either direct or indirect, institutional support, or association with an entity in the biomedical field which may be perceived to have potential conflict of interest with this work. For full disclosure statements refer to http://dx.doi.org/10.1016/j.arth.2016.08.006.

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Health Policy and EconomicsDetermining Cost-Effectiveness of Total Hip and Knee Arthroplasty Using the Short Form-6D Utility Measure

Abstract

Background

Methods

Results

Conclusion

Section snippets

Methods

Results

Discussion

Best Pract Res Clin Rheumatol

J Health Econ

J Arthroplasty

Spine J

J Arthroplasty

Osteoarthritis Cartilage

Value Health

Projections of primary and revision hip and knee arthroplasty in the United States from 2005 to 2030

J Bone Joint Surg Am

Cost and utilization of healthcare services for hip and knee replacement

J Med Econ

Variability in costs associated with total hip and knee replacement implants

J Bone Joint Surg Am

Comparing short form 6D, standard gamble, and Health Utilities Index Mark 2 and Mark 3 utility scores: results from total hip arthroplasty patients

Qual Life Res

Health Policy and Economics
Determining Cost-Effectiveness of Total Hip and Knee Arthroplasty Using the Short Form-6D Utility Measure