Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are extraordinarily successful procedures in the treatment of severe osteoarthritis.1 This success has resulted in enormous strain on the US health care system as demand for these procedures continues to rise.2 In an attempt to control the increasing costs associated with total joint arthroplasty (TJA), a dramatic shift toward value-based health care delivery, centered on maximizing outcomes for each dollar spent, has been seen in the past decade.3 A major determinant of the value-based equation is the outcome of treatment from the perspective of the patient, which, in turn, has been shown to be largely dependent on fulfilment of pre-treatment expectations.4
There is growing recognition that setting appropriate treatment expectations applies not only to the surgical episode of care, but also to the entire cycle of osteoarthritis care. Models of care likely to succeed in the future health care environment will approach osteoarthritis from a comprehensive perspective, incorporating multidisciplinary teams of co-located clinical and non-clinical providers, or so-called integrated practice units.5 Maximizing efficiency in this model depends on the timely and accurate identification of surgical and nonsurgical osteoarthritis patients. In the traditional fragmented delivery model, it is not uncommon for providers in a surgical practice to see many patients who stand to benefit from these operations who prefer to avoid surgery.6 The time and effort required to manage such patients in a busy surgical practice can result in poor efficiency, suboptimal resource utilization, and most importantly, dissatisfaction on the part of patients.7 Matching patient preferences with appropriate care teams and treatment modalities can improve patients' satisfaction with their overall care plan.
Numerous studies have analyzed patient decision making surrounding TJA, and themes that emerge throughout the literature are arthritis severity, overall health status, whether a physician has introduced TJA as a treatment option, the patient–physician relationship, personal experiences with the health care system, experiences of patients' social network, and fear of the procedure and anticipated recovery.8–11 Identifying readily available metrics to help triage patients through an often complex treatment system can improve the ability to match treatment to patient preferences. It is currently unknown whether there is a specific functional threshold that is associated with surgical aversion, and there is only limited evidence that a preference toward nonoperative care results in a higher or lower likelihood of actually undergoing TJA.6 The results of such an analysis may help to more efficiently deploy health care resources to match appropriate care methods to patient preferences.
The purpose of this study was to determine if there is a difference in prospectively collected osteoarthritis severity scores between patients who are averse to surgery compared with those who are amenable to surgery. The authors hypothesized that (a) TJA is unlikely to be scheduled by patients who initially present to the outpatient clinic with an aversion to surgery, and (b) patients with higher functional scores will have a higher tendency toward aversion to TJA. They further sought to determine preoperative thresholds that predict a high probability of an aversion to hip and knee replacement surgery while controlling for factors such as living status, age, sex, radiographic findings, and prior treatment.
Materials and Methods
A prospective cross-sectional survey was administered to all new patients presenting for an initial visit to a single fellowship-trained adult reconstruction surgeon's (A.J.S.) office at an academic medical center during a 5-month period. Patients were excluded if they did not wish to participate in the full survey, were being evaluated for a condition other than hip or knee arthritis, or had previously undergone an arthroplasty procedure on the joint being evaluated. This study received institutional review board approval.
The survey included the International Consortium for Health Outcomes Measurement Hip and Knee Osteoarthritis Working Group standard set of outcome measures for monitoring, comparing, and improving the care of patients with hip and knee osteoarthritis.12 The outcomes assessed by the standard set include joint pain, physical functioning, health-related quality of life, work status, living arrangements, mortality, reoperations, readmissions, and overall satisfaction with treatment results. Specific patient-reported outcome measures included in the standard set are the Hip disability and Osteoarthritis Outcome Score (HOOS),13 the Knee injury and Osteoarthritis Outcome Score (KOOS),14 and the Veterans RAND 12-Item Health Survey (VR-12) score. The Veterans RAND 12-Item Health Survey was developed from the Veterans RAND 36-Item Health Survey, which was developed and modified from the original RAND version of the 36-Item Health Survey version 1.0 (also known as the MOS SF-36).15 The VR-12 produces two summary scores, the physical component score (PCS) and the mental component score (MCS), which allow differentiating between physical and mental health.
There was an additional question regarding patient preference for or against surgical treatment for osteoarthritis:
Which of the following most accurately describes your preferences?
I have heard about joint replacement, and I am interested in this as an option.
I have never heard about joint replacement, but I am interested in this as an option if it can help me.
I am not interested in joint replacement, and I want to avoid surgery at all costs.
Patients who selected answer C were labelled “averse to surgery,” while those who responded otherwise were considered to be amenable to surgical treatment. A free-text entry allowed for manual review of those who selected answer D. None of the free-text answers were deemed to reflect a strong aversion to surgery (eg, “doctor referred me for evaluation of my hip pain”).
Measurement of Symptom Severity, Baseline Health, and Radiographic Evaluation
Patient-reported HOOS and KOOS at the time of presentation were calculated from the collected short versions of these scoring systems (HOOS for Joint Replacement, KOOS for Joint Replacement), and VR-12 PCS and MCS were calculated using instructional literature provided by the scoring system's developers.
Standard radiographs of the hip and knee were obtained at the time of evaluation. Hip radiographs included a supine anteroposterior pelvis, anteroposterior hip, and cross-table lateral and were graded using the Tönnis classification system for hip osteoarthritis.16 Knee radiographs included standing anteroposterior view, standing flexion posteroanterior view, standing lateral view, and sunrise view. Knee radiographs were graded according to the Kellgren–Lawrence classification system.17
The treatment plan ultimately chosen by each individual patient was determined at the clinic visit. Additional chart review occurred at the most recent follow-up after the initial clinical evaluation when the survey was administered.
Statistical analysis was performed with the aim of understanding factors that predicted a patient as being averse to surgery, compared with patients who were amenable to surgery. Variables that were considered as potential predictors included age, sex, type of primary complaint (hip or knee, as determined by the highest pain score), radiographic findings, satisfaction with prior treatment, work status, highest level of schooling achieved, living status (live alone or live with spouse/family), baseline physical and mental health scores (VR-12), and functional scores (HOOS and KOOS). Normally distributed data were analyzed using the Student's t test, and categorical data were analyzed using the chi-square test. A univariate logistic regression model was created using a positive response to answer C (above) as the response variable. Receiver operating characteristic curves were used to evaluate the functional scores for all patients in the study, and the area under the curve was used as a measure of the model's overall accuracy. Youden's J statistic was used to aid selection of optimal cutoff points, maximizing sensitivity and specificity of the functional scores in predicting aversion to TJR.
Statistical analysis was performed using JMP Pro 14 (SAS Institute, Inc, Cary, North Carolina).
A total of 126 consecutive patients were offered participation in the study during the 5-month period. Twelve patients were unwilling to participate, and an additional 11 patients were seen for a condition other than hip or knee arthritis or had previously undergone an arthroplasty procedure. Thus, 103 patients were included in the analysis (Figure 1). The cohort included 59 women (57.3%) and 44 men (42.7%), with a mean age of 67.3 years (range, 40 to 98 years).
Flow diagram of patients included in the study.
Mean KOOS and HOOS for the entire cohort were 54.0 (range, 0–100) and 64.5 (range, 25–100), respectively. Mean maximum pain ratings on a scale of 0 to 10 for knee and hip were 5.1 and 4.1, respectively. The distribution of Kellgren–Lawrence scores for knee radiographs was 21 grade 2 (30%), 13 grade 3 (18.6%), and 36 grade 4 (51.4%). The distribution of Tönnis scores for hip radiographs was 2 grade 0 (3.9%), 22 grade 1 (43.1%), 13 grade 2 (25.5%), and 14 grade 3 (27.5%).
At survey administration at the initial clinical evaluation, 22 patients (21.4%; 95% confidence interval, 14.5%–30.2%) were averse to TJA. Twenty patients among the entire cohort (19.4%; 95% confidence interval, 12.9%–28.1%) ultimately underwent TJA. The proportion of patients who underwent surgery was significantly smaller among those averse compared with those not averse to surgery (4.6% vs 23.5%, P<.05).
Baseline characteristics were similar between the two groups. There were no statistically significant differences in age, sex, radiographic findings, type of primary complaint, satisfaction with prior treatment, work status, education, living status, or baseline physical or mental health (Table 1). In addition, functional scores were not significantly different between patients who underwent TJA compared with those who did not (KOOS, 50.9 vs 54.7, P=.44; HOOS, 62.2 vs 65.1, P=.54).
Patient Demographics Overall and by Surgical Preference Category
Predictors of Aversion
The functional scores for patients averse to TJA were significantly higher than those for patients amenable to surgical treatment (KOOS, 66.6 vs 50.6, P<.001; HOOS, 73.2 vs 62.2, P<.05) (Table 2). Bivariate logistic regression modelling revealed a significant association between functional scores and aversion to TJA (modelling estimate KOOS, −0.05, P<.005; modelling estimate HOOS, −0.03, P<.05). Optimal cutoff values for all patients overall were 57.1 and 58.9, with an area under the curve of 0.73 and 0.68, for KOOS and HOOS, respectively (Figure 2).
Functional Scores Analyzed by Aversion to Surgical Intervention
Receiver operating characteristic curves for Knee injury and Osteoarthritis Outcome Score (A) and Hip disability and Osteoarthritis Outcome Score (B) at the time of initial evaluation. The x-axis represents the proportion of false-positive results (ie, cases where the functional score predicted aversion, but the patient was not averse; also referred to as 1-specificity). The y-axis represents the proportion of true-positive results (ie, cases where the functional score predicted aversion, and the patient was averse; also referred to as sensitivity). The tangential line corresponds to the optimal cutoff value for functional scores (the point that maximizes the area under the curve) for predicting aversion to total joint arthroplasty.
Despite the success of TJA, a subset of patients are averse to the procedure. Prior studies have outlined several reasons for this aversion, including patients' prior experiences with the health care system, fear, rejecting the medicalization of arthritis care, and misunderstanding of the pain and disability that warrant surgery.6,7,18–21 In the current study, the authors found that patients' functional scores were correlated with aversion to surgery, and all but one of the patients in this series who initially reported being averse to surgical management elected not to proceed with TJA. While the authors found no association between aversion and age, sex, education status, living arrangements, radiographic findings, or satisfaction with prior treatment, functional scores were predictive of aversion for patients overall. The authors are unaware of another study analyzing patient preferences while controlling for radiographic and functional osteoarthritis severity scores. The results of this study can help improve the pre-visit identification of patients who are unlikely to proceed with TJA following initial clinical evaluation.
Several factors have been shown to be associated with willingness to undergo or aversion to TJA, including patients' perception of disability, demographics, and prior experience with the health care system. Hawker et al6 found that patients commonly overestimated the pain and disability necessary to warrant TJA and that these misconceptions were strongly associated with unwillingness to undergo TJA. These authors advocated for population-level interventions to educate patients about the appropriate degree of disability to warrant TJA. They found that patients normalized osteoarthritis as normal aging, overestimated the amount of pain and disability required to warrant surgery, and believed that if they would benefit from TJA, a surgeon would advise them to undergo surgery.10 In a review of 331 patients undergoing primary hip or knee arthroplasty, Lavernia et al22 found racial disparity in the perception of TJA outcomes, with blacks having higher association of fear subscale and lower outcome scores following TJA. Along these lines, in a group of 639 African American patients with moderate to severe osteoarthritis, Ibrahim et al23 showed that an educational intervention significantly increased patient willingness to consider TKA. Hudak et al10 interviewed elderly individuals identified as TJA candidates who were unwilling to undergo the procedure. In the current study, the authors tested for an association between aversion and multiple demographic variables, including age, sex, education, and living arrangements. They were unable to detect an association between aversion and any of these variables except for functional scores.
Previous treatment, symptom severity, and experience with the health care system are also potentially associated with aversion to surgical intervention. Dosanjh et al24 showed that patients made the decision to undergo TJA when their limitations affected their basic activities of daily living, relationships, and psychological well-being. Ballantyne et al18 conducted interviews with patients who expressed preference to avoid surgery despite being appropriate candidates. These patients tended to reject their arthritis as a medical condition (so-called medicalization), instead expressing the opinion that osteoarthritis is a “natural” part of aging. Patients also had previous negative medical/surgical encounters (including distant past and of friends/family), and they accepted doing nothing as a viable option. Again, the current study tested the relationship between prior experiences with the health care system and aversion, finding no association.
An interesting finding of this study was that the baseline characteristics of patients averse to surgery were similar to those of patients willing to undergo surgical intervention, with the exception of functional scores. This held true not only for demographic profiles, but also for severity ratings on radiographs. While one might expect patients with worse radiographic findings to be more amenable to surgical intervention, the authors saw no correlation between surgical aversion and radiographic findings. Prior literature has demonstrated that preoperative functional scores are useful in predicting outcomes following TJA.25 The current findings echo these results and further establish an association between functional scores and a patient's willingness to proceed with surgery. It is certainly conceivable that, even in the setting of severe findings on radiograph, higher functional scores may lead a patient to be less willing to proceed with surgery. Thus, patients with lower functional scores may be less averse to surgery, even if their radiographic findings indicate more advanced disease.
This study had several limitations. The patient population was drawn from a single surgeon's practice at a single academic medical center; therefore, the conclusions may not be generalizable to other practice settings. A variety of surgeon-related (eg, surgeon personality, engagement with the patient, reputation) and non–surgeon-related (eg, abrasive office staff, clinic experience, wait times) factors were not included in the analysis and may have played a role in a patient's willingness to undergo surgery. In a future study, controlling for these factors, along with standardized patient satisfaction scores, and including patients of more surgeons in varied practice settings would help mitigate these limitations. A second limitation was the brief time to follow-up; it is certainly plausible that patients who were initially averse to TJA may have returned for surgery after other nonoperative modalities failed to provide symptom relief or may have opted for surgery elsewhere. However, as the intended purpose was to determine factors associated with aversion and decision making at the initial clinical visit, the authors do not believe that this limitation significantly altered the conclusions of this study.
This study illustrated that prospectively collected arthritis severity scores are useful in predicting aversion to TJA, and that aversion to TJA is a strong predictor of the treatment chosen at the initial clinical visit. As bundled payments move upstream to the condition level,26 these results can be useful in patient triage and resource management for osteoarthritis integrated practice units. Patients with higher functional scores identified as averse to surgery may be better served by first meeting with a provider specializing in nonoperative osteoarthritis care.
- Skou ST, Roos EM, Laursen MB, et al. A randomized, controlled trial of total knee replacement. N Engl J Med. 2015;373(17):1597–1606. doi:10.1056/NEJMoa1505467 [CrossRef] PMID:26488691
- Kurtz S, Ong K, Lau E, Mowat F, Halpern M. Projections of primary and revision hip and knee arthroplasty in the United States from 2005 to 2030. J Bone Joint Surg Am. 2007;89(4):780–785. doi:10.2106/JBJS.F.00222 [CrossRef] PMID:17403800
- Porter ME. What is value in health care?N Engl J Med.2010;363(26):2477–2481. doi:10.1056/NEJMp1011024 [CrossRef] PMID:21142528
- Noble PC, Conditt MA, Cook KF, Mathis KB. The John Insall Award: patient expectations affect satisfaction with total knee arthroplasty. Clin Orthop Relat Res. 2006;452(452):35–43. doi:10.1097/01.blo.0000238825.63648.1e [CrossRef] PMID:16967035
- Keswani A, Koenig KM, Bozic KJ. Value-based healthcare: Part 1. Designing and implementing integrated practice units for the management of musculoskeletal disease. Clin Orthop Relat Res. 2016;474(10):2100–2103. doi:10.1007/s11999-016-4999-5 [CrossRef] PMID:27457622
- Hawker GA, Wright JG, Badley EM, Coyte PC. Perceptions of, and willingness to consider, total joint arthroplasty in a population-based cohort of individuals with disabling hip and knee arthritis. Arthritis Rheum. 2004;51(4):635–641. doi:10.1002/art.20524 [CrossRef] PMID:15334438
- Sansom A, Donovan J, Sanders C, et al. Routes to total joint replacement surgery: patients' and clinicians' perceptions of need. Arthritis Care Res (Hoboken).2010;62(9):1252–1257. doi:10.1002/acr.20218 [CrossRef] PMID:20506507
- Suarez-Almazor ME, Richardson M, Kroll TL, Sharf BF. A qualitative analysis of decision-making for total knee replacement in patients with osteoarthritis. J Clin Rheumatol. 2010;16(4):158–163. doi:10.1097/RHU.0b013e3181df4de4 [CrossRef] PMID:20414128
- Parks ML, Hebert-Beirne J, Rojas M, Tuzzio L, Nelson CL, Boutin-Foster C. A qualitative study of factors underlying decision making for joint replacement among African Americans and Latinos with osteoarthritis. J Long Term Eff Med Implants. 2014;24(2–3):205–212. doi:10.1615/JLongTermEffMedImplants.2014010428 [CrossRef] PMID:25272219
- Hudak PL, Clark JP, Hawker GA, et al. “You're perfect for the procedure! Why don't you want it?” Elderly arthritis patients' unwillingness to consider total joint arthroplasty surgery: a qualitative study. Med Decis Making. 2002;22(3):272–278. PMID:12058784
- Barlow T, Griffin D, Barlow D, Realpe A. Patients' decision making in total knee arthroplasty: a systematic review of qualitative research. Bone Joint Res. 2015;4(10):163–169. doi:10.1302/2046-3758.410.2000420 [CrossRef] PMID:26450640
- Rolfson O, Wissig S, van Maasakkers L, et al. Defining an international standard set of outcome measures for patients with hip or knee osteoarthritis: consensus of the International Consortium for Health Outcomes Measurement Hip and Knee Osteoarthritis Working Group. Arthritis Care Res (Hoboken). 2016;68(11):1631–1639. doi:10.1002/acr.22868 [CrossRef] PMID:26881821
- Nilsdotter AK, Lohmander LS, Klässbo M, Roos EM. Hip disability and Osteoarthritis Outcome Score (HOOS): validity and responsiveness in total hip replacement. BMC Musculoskelet Disord. 2003;4(1):10. doi:10.1186/1471-2474-4-10 [CrossRef] PMID:12777182
- Roos EM, Toksvig-Larsen S. Knee injury and Osteoarthritis Outcome Score (KOOS): validation and comparison to the WOMAC in total knee replacement. Health Qual Life Outcomes. 2003;1(1):17. doi:10.1186/1477-7525-1-17 [CrossRef] PMID:12801417
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- Busse J, Gasteiger W, Tönnis D. [A new method for roentgenologic evaluation of the hip joint: the hip factor]. Arch Orthop Unfallchir. 1972;72(1):1–9. doi:10.1007/BF00415854 [CrossRef] PMID:5020681
- Kellgren JH, Lawrence JS. Radiological assessment of osteoarthrosis. Ann Rheum Dis. 1957;16(4):494–502. doi:10.1136/ard.16.4.494 [CrossRef] PMID:13498604
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- Frankel L, Sanmartin C, Conner-Spady B, et al. Osteoarthritis patients' perceptions of “appropriateness” for total joint replacement surgery. Osteoarthritis Cartilage. 2012;20(9):967–973. doi:10.1016/j.joca.2012.05.008 [CrossRef] PMID:22659599
- Hamel MB, Toth M, Legedza A, Rosen MP. Joint replacement surgery in elderly patients with severe osteoarthritis of the hip or knee: decision making, postoperative recovery, and clinical outcomes. Arch Intern Med. 2008;168(13):1430–1440. doi:10.1001/archinte.168.13.1430 [CrossRef] PMID:18625924
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- Lavernia CJ, Alcerro JC, Rossi MD. Fear in arthroplasty surgery: the role of race. Clin Orthop Relat Res. 2010;468(2):547–554. doi:10.1007/s11999-009-1101-6 [CrossRef] PMID:19763716
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Patient Demographics Overall and by Surgical Preference Category
|Characteristic||Overall||Averse to Surgery||Not Adverse to Surgery||Pa|
|Age, mean (range), y||67.3 (40–98)||66.3 (40–98)||67.5 (43–89)||.63|
| Male||44 (42.7%)||10 (45.5%)||34 (42.0%)|
| Female||59 (57.3%)||12 (54.5%)||47 (58.0%)|
|Primary complaint, No.||.34|
| Hip||37 (35.9%)||6 (27.3%)||31 (38.3%)|
| Knee||66 (64.1%)||16 (72.7%)||50 (61.7%)|
|Radiographic finding, No.b|
| Tönnis grade||.19|
| 0||2 (3.9%)||1 (11.1%)||1 (2.4%)|
| 1||22 (43.1%)||6 (66.7%)||16 (38.1%)|
| 2||13 (25.5%)||1 (11.1%)||12 (28.6%)|
| 3||14 (27.5%)||1 (11.1%)||13 (30.9%)|
| Kellgren–Lawrence grade, No.||.52|
| 2||21 (30.0%)||6 (42.9%)||15 (26.8%)|
| 3||13 (18.6%)||2 (14.2%)||11 (19.6%)|
| 4||36 (51.4%)||6 (42.9%)||30 (53.6%)|
|Satisfaction with prior treatment, No.||.38|
| Very satisfied||6 (5.8%)||0||6 (7.4%)|
| Satisfied||17 (16.5%)||4 (18.2%)||13 (16.0%)|
| Neither satisfied nor unsatisfied||41 (39.8%)||12 (54.5%)||29 (35.8%)|
| Unsatisfied||23 (22.3%)||3 (13.6%)||20 (24.7%)|
| Very unsatisfied||16 (15.5%)||3 (13.6%)||13 (13.0%)|
|What is your work status? No.||.66|
| Working full time||32 (31.1%)||7 (31.8%)||25 (39.9%)|
| Working part time||7 (6.8%)||3 (13.6%)||4 (4.9%)|
| Not working by choice||42 (40.8%)||7 (31.8%)||35 (43.2%)|
| Unable to work due to osteoarthritis||2 (1.9%)||0||2 (2.5%)|
| Unable to work due to a condition other than osteoarthritis||7 (6.8%)||2 (9.2%)||5 (6.2%)|
| Other||13 (12.6%)||3 (13.6%)||10 (12.3%)|
|What is the highest level of schooling you have achieved? No.||.13|
| Primary||3 (2.9%)||2 (9.2%)||1 (1.3%)|
| Secondary||25 (24.3%)||4 (18.1%)||21 (25.9%)|
| Tertiary||75 (72.8%)||16 (72.7%)||59 (72.8%)|
|What is your living status? No.||.97|
| I live alone||19 (18.5%)||4 (18.2%)||15 (18.5%)|
| I live with a partner/spouse/family member||84 (81.5%)||18 (81.8%)||66 (81.5%)|
|Veterans RAND 12-Item Health Survey score, mean (range)||80.5 (45.0–114.1)||86.2 (45.0–112.7)||78.9 (47.0–114.1)||.07|
| Physical component||30.0 (13.1–57.3)||32.5 (16.7–51.6)||29.3 (13.1–57.3)||.21|
| Mental component||50.5 (21.3–70.3)||53.7 (21.3–70.4)||49.7 (21.3–66.7)||.16|
Functional Scores Analyzed by Aversion to Surgical Interventiona
|Functional Score||Mean||Range||95% Confidence Interval||P|
| Not averse||62.2||25.1–100||58.2–66.2|
| Not averse||50.6||8.1–100||46.5–54.7|