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Management of Osteoarthritis of the Knee by Primary Care Physicians
Lorrie A. Mamlin, MPH;
Catherine A. Melfi, PhD;
Michael L. Parchman, MD;
Benjamin Gutierrez, PhD;
Deborah I. Allen, MD;
Barry P. Katz, PhD;
Robert S. Dittus, MD;
David A. Heck, MD;
Deborah A. Freund, PhD
Arch Fam Med. 1998;7:563-567.
ABSTRACT
Background Most patients with osteoarthritis (OA) are treated by primary care physicians (in this article, primary care physicians are family physicians and general internists).
Objective To describe and compare the self-reported practice patterns of family physicians and general internists for the evaluation and management of severe OA of the knee, including factors that might influence referral for total knee replacement.
Design, Setting, and Participants A survey was developed and mailed to randomly selected community family physicians and general internists practicing in Indiana.
Main Outcome Measure Self-reported physician practice patterns regarding OA of the knee.
Results Physical examination was the most common method of evaluating OA of the knee. Family physicians were more likely to examine for crepitation, joint stability, and quadriceps muscle strength than were general internists (P<.05). Patients with OA of the knee treated by family physicians were more likely to receive nonsteroidal anti-inflammatory drugs or oral corticosteroids and were less likely to receive aspirin, acetaminophen, or narcotics compared with patients treated by general internists. Six patient characteristics were rated as positive factors favoring a referral for possible total knee replacement, 8 characteristics were rated as negative, and 5 were rated as not a factor in the decision about referral.
Conclusions Results from this study suggest that additional research is needed to determine the evaluative techniques for OA of the knee that provide the most useful information for management decisions, the management techniques that maximize patient outcomes, and the criteria that should be used to select patients who would benefit most from referral for possible total knee replacement.
INTRODUCTION
OSTEOARTHRITIS (OA) is the most common disease affecting joints.1 It is the 16th most common principal diagnosis for visits to primary care physicians (in this article, primary care physicians are family physicians and general internists) among patients of all ages, the eighth most common in patients between the ages of 65 and 74 years, and the third most common in patients older than 75 years.2 Evidence of OA has been found in 80% of radiographs in persons older than 70 years.3 Despite the high prevalence of this disease in primary care practice, little is known about how OA is managed by primary care physicians.
Recent reports document how primary care physicians and rheumatologists would manage a hypothetical case of OA.4-6 The results of these studies suggest that 65% to 75% of family physicians and general internists would prescribe nonsteroidal anti-inflammatory drugs (NSAIDs) despite their higher cost and debated superiority over pure analgesics.7 Compared with rheumatologists, primary care physicians report less frequent use of nondrug therapy, such as physical therapy and exercises.6
For patients with severe OA of the knee, joint replacement has become an accepted treatment alternative. Rates of joint replacement are increasing, and a recent meta-analysis of studies of patient outcomes found that total knee replacement (TKR) was a "safe and effective procedure. . . ."8 Stross and Bole9 evaluated an educational intervention designed to inform primary care physicians of the value of joint replacement. Audits of hospital discharge records in community hospitals used by these primary care physicians found that the rate of discharges for TKR doubled after the educational intervention.
The purpose of this study was to describe and compare the self-reported practice patterns of family physicians and general internists for the evaluation and management of severe OA of the knee, including factors that might influence referral for TKR. This study was conducted as part of a larger project studying the outcomes of TKR through one of the Patient Outcomes Research Teams (PORTs) funded by the Agency for Health Care Policy and Research, Rockville, Md.10 The principal focus of the TKR PORT was to evaluate outcomes from TKR surgery.
METHODS
A panel composed of a family physician (D.I.A.), a general internist, an orthopaedic surgeon (D.A.H.), a biostatistician (B.P.K.), and the director of a survey research center developed a written survey that was designed to obtain physicians' self-reports of their practice patterns, perceptions, and attitudes for the evaluation and management of severe OA of the knee. In the survey, physicians were first asked whether during the past year they had "treated or referred for treatment any patients with severe osteoarthritis of the knee." Those who responded no were excluded from further analysis. Those who responded yes were asked how many patients with severe OA of the knee they had treated or referred during the past 2 weeks. The second question provided a list of 11 possible treatment or management options for OA of the knee. Physicians were asked to report the percentage of their patients with OA of the knee for whom they had prescribed each treatment during the past year. The third question listed 10 techniques used in the evaluation of OA of the knee and asked for a percentage response similar to that requested in the second question. Finally, physicians were asked about the indications for TKR. They were asked to indicate the effect of patient age, weight, walking limitations, and 24 additional patient characteristics on their decision to refer a patient for possible TKR. The survey was reviewed by an advisory board of primary care physicians for content and clarity. A copy of the survey is available on request.
A sampling frame of Indiana family physicians and general internists was developed from all available sources: (1) the Indiana Physician Profile maintained at the Indiana University Department of Family Medicine, Indianapolis; (2) the Indiana Medical Licensing Bureau, Indianapolis; (3) Medicare billing data; and (4) the American Medical Association (Chicago, Ill) Physician Masterfile for Indiana. From this frame, 100 primary care physicians were randomly selected for pilot testing of the mail surveys. The pilot test yielded a 30% response rate, and no difficulties were noted in responding to the questions.
Simple random samples of 300 family physicians and 300 general internists were selected from the sampling frame to receive the survey by mail. A cover letter, signed by the chairpersons of the Indiana University Departments of Medicine and Family Medicine, accompanied the survey. The letter introduced the project, explained the purpose of the survey, and encouraged participation. Two follow-up mailings were sent to nonrespondents.
Descriptive analyses were performed by calculating the mean responses for each question. Most questions asked for physicians to report a percentage of patients for whom they recommended a particular therapy, and these mean percentages are reported. In addition, mean responses were calculated for family physicians and general internists separately, so that comparisons could be made between the 2 specialties. These comparisons were made by using the Student t test. For the question focusing on how patient characteristics would influence referral for possible TKR, the 5-point Likert-type scale response was collapsed into 3 categories: a negative factor against referral, not a factor, and a positive factor favoring referral. Patient characteristics that received less than a 60% response from the physicians in any of the 3 categories (ie, fewer than 60% of physicians thought it was a negative factor or a positive factor or not a factor in referral)were reported as "clinical disagreement."
RESULTS
Of the 300 family physicians and 300 general internists who were sampled, 86 and 107, respectively, were excluded for one of the following reasons: (1) retired or not practicing, (2) not a family physician or general internist, (3) deceased, or (4) not locatable. Of the 214 eligible family physicians, 70 returned completed surveys for a response rate of 32.7%. Of the 193 eligible general internists, 72 returned completed surveys for a response rate of 37.3%. The overall response rate was 34.9%. No significant differences were noted between respondents and nonrespondents in age, years of practice since medical school, sex, the percentage practicing in metropolitan statistical area counties, and the percentage who were graduates of the Indiana University Medical School (Table 1).
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Table 1. Characteristics of Respondents and Nonrespondents
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Most respondents (92.3%) reported treating or referring a patient with severe OA of the knee during the past year, including 64 family physicians (91%) and 67 general internists (93%); thus, 131 physicians were included in further analysis. During the 2 weeks before completing the survey, the 131 physicians treated or referred, on average, 4.3 patients (range, 0-21 patients) with severe OA of the knee; family physicians reported that they treated or referred an average of 3.5 patients (range, 0-12 patients) compared with general internists, who reported an average of 5.1 patients (range, 0-12 patients) with OA of the knee (P<.05).
Methods used to evaluate OA of the knee are given in Table 2. The most frequently used techniques for evaluating severe OA of the knee were examination for crepitation, assessment of knee range of motion, and a check for pedal pulses. The use of standing knee radiographs was much less common than the use of non–weight-bearing knee radiographs . Family physicians were significantly more likely to examine for crepitation, joint stability, and quadriceps muscle strength than were general internists. No other statistically significant differences were noted between family physicians and general internists in the evaluation of severe OA of the knee.
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Table 2. Evaluation of Osteoarthritis of the Knee by Primary Care Physicians*
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The most frequent method of managing severe OA of the knee was drug therapy (Table 3). The most commonly prescribed regimen was NSAIDs. General internists were significantly more likely than family physicians to prescribe aspirin, acetaminophen, or narcotics. Family physicians were more likely than general internists to prescribe NSAIDs or oral corticosteroids and to inject corticosteroids intra-articularly. Instruction or referral for weight loss was the second most common method of management following drug therapy; the third most common was referral for physical therapy. Few patients were referred to an orthopaedic surgeon for evaluation for possible TKR or knee arthroscopy or to another physician for nonsurgical management. No significant differences in referral rates were noted between family physicians and general internists.
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Table 3. Management of Osteoarthritis of the Knee by Primary Care Physicians*
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Patient characteristics were related to referral for possible TKR. When asked whether a patient could be too old to undergo TKR, 33.9% of physicians responded yes. The median reported maximum age for TKR was 87.5 years. When physicians were asked whether a patient could be too young to undergo TKR, 43.9% responded yes. The median reported minimum age was 40 years. Most physicians (82.5%) responded yes when asked whether a patient could weigh too much to undergo TKR. The median of the reported maximum weight for knee replacement was 123.8 kg (275 lb) (range, 67.5-180.0 kg [150-400 lb]). The majority of physicians (69.9%) reported that the number of blocks a patient can walk without pain is not a factor in referring for TKR. Of the remaining 30.1% who used the minimum number of blocks that a patient can walk as a criterion for referral for possible TKR, the mean number of minimum blocks reported was 1.5 (range, 1-5 blocks).
The relative importance of 24 patient characteristics in a physician's decision to refer a patient for possible TKR is reported in Table 4. Similar responses were noted for family physicians and general internists. The presence of pain not responsive to drug therapy and the presence of substantial weight-bearing pain received the strongest ratings as factors favoring a referral for possible TKR. Patient race and sex were the factors most commonly reported to not influence possible TKR referral. The presence of alcohol or drug abuse and the presence of peripheral vascular disease were rated as the strongest negative factors against a referral for possible TKR. Clinical disagreement existed for 5 (21%) of the 24 patient characteristics: septic OA of the knee more than 1 year ago, the lack of health insurance, isolated patellofemoral OA, a patient demand for TKR, and painful feet.
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Table 4. Percentage of Agreement Among Primary Care Physicians* About Patient Characteristics That Influence the Decision to Refer for Possible Total Knee Replacement
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COMMENT
Osteoarthritis of the knee is a common problem in primary care. More than 90% of the primary care physicians in the sample for the present study reported evaluating and managing severe OA of the knee during the previous 2 weeks, with a mean of 4.3 patients seen. Note, however, that we relied on the primary care physicians' individual assessments for determining whether patients had severe OA of the knee. The physical examination was the most common method of evaluating severe OA of the knee, especially assessment of crepitation, range of motion, and joint stability. Slightly more than 60% of the primary care physicians participating in the study obtained non–weight-bearing knee radiographs. One possible explanation for this finding is that radiographic findings in OA may not correlate well with patient symptoms or functional status. For this reason, knee radiographs may not be helpful to primary care physicians in the clinical management of OA of the knee. Standing knee radiographs have been reported to provide more important diagnostic information for OA of the knee than non–weight-bearing knee radiographs.11 Our sample of physicians reported relatively infrequent use (17.3%) of this technique.
The use of NSAIDs dominates the treatment modalities used in the management of OA of the knee by the primary care physicians participating in the present study, a finding that supports the hypothetical case studies of Mazzuca et al4, 6 and Holt and Mazzuca.5 They reported that almost half of the patients with OA of the knee were instructed about or referred for weight loss. This finding supports those of other studies that have found a relationship between obesity and OA of the knee.12 More than 80% of the physicians also reported that a patient can weigh too much to be considered a candidate for TKR.12
According to the primary care physicians' assessments, patients with severe OA of the knee were predominantly treated without referral to specialists. Fewer than 8% of patients were referred to another physician for nonsurgical management, and fewer than 20% of patients were referred to an orthopaedic surgeon for evaluation. Only 7% of patients were referred specifically for possible TKR. Slightly more than 7% of patients were referred for arthroscopy, a technique still under evaluation for its usefulness in the management of OA of the knee.13 These results support previous findings that most cases of OA of the knee are managed solely by primary care physicians with little assistance from other specialists.1-2 The optimal rate of appropriate referral for TKR remains unknown, as do the appropriate criteria for selecting patients who would receive maximum benefit from TKR.
The primary care physicians participating in the present study agreed on how they would rate the importance of 19 of the 24 patient characteristics in their decision to refer for TKR. Only 5 items had less than 60% agreement about their role in the referral decision. The factors favoring referral were dominated by patient pain and discomfort. Race, sex, and having medical insurance were generally agreed on as not important in making a decision to refer. The factors against referral consisted mostly of coexisting conditions, such as alcohol or other drug abuse, peripheral vascular disease, active skin infection, or a major psychiatric disorder. Primary care physicians may view these as factors that would lead to poorer outcomes of TKR, and, thus, they may be less inclined to refer patients with these conditions. Disagreement was found mostly on items that might be a negative factor for referral: septic knee arthritis, no health insurance, isolated patellofemoral arthritis, and painful feet.
The presence of clinical disagreement in the rating of the importance of 5 (21%) of the 24 patient characteristics in a decision to refer for possible TKR illustrates the uncertainty that may cause the practice style variation found in managing common primary care problems. Berg14 found little agreement among family physicians for the management of an uncomplicated urinary tract infection in a hypothetical female patient. Adamson et al,15 who compared treatment of hypertension by family physicians and general internists, found significant differences in the frequency of follow-up visits and in the frequency of medication changes when blood pressure was uncontrolled. Petitti and Grumbach16 found variation between family physicians and general internists in recommendations about revisit intervals for hypothetical patients with diabetes, angina, or hypertension. The results of our study suggest that a similar practice style variation may exist in the decision to refer a patient with severe OA of the knee.
Our findings are limited by the low response rate of 34.9%. Although the response rate is low and the findings may not be generalizable to the entire population of primary care physicians in the United States, the present study represents an attempt to quantify the decision-making process of physicians caring for patients with severe OA of the knee. A strength of these data is the use of 2 separate groups of community-based primary care physicians.
Another limitation of the study is that physicians were not asked to justify their diagnosis of severe OA of the knee according to diagnostic criteria; thus, the results are based solely on the physicians' evaluations in diagnosing this condition. This could be one reason there seems to be so much variation in physician practice patterns. Clinical confirmation of severe OA of the knee was beyond the scope of this study, but future studies could verify diagnoses.
Family physicians and general internists need the following research findings: (1) the evaluative techniques for OA of the knee that provide the most useful information for management, (2) the management techniques that maximize clinical outcomes, and (3) the criteria that should be used to select patients who would benefit most from referral. The findings of the present study suggest that some clinical disagreement exists among primary care physicians in each of these areas. Since the most important objective is an improved clinical outcome for patients with severe OA of the knee, additional studies are needed to evaluate how current standards of practice for evaluating, treating, and referring patients with severe OA of the knee by primary care physicians relate to patient outcomes, such as quality of life, pain, and functional status.
AUTHOR INFORMATION
Accepted for publication September 29, 1997.
This research was supported by grant 06432 from the Agency for Health Care Policy and Research, Rockville, Md, to Indiana University and subgrantees to establish a Total Knee Replacement Patient Outcomes Research Team.
Opinions in this article do not necessarily reflect the opinions of the Agency for Health Care Policy and Research.
We express our appreciation to Evan Melrose, MD, for preparing the data for analysis.
Reprints: Lorrie A. Mamlin, MPH, Center for Health Services Research (11H), Richard L. Roudebush Veterans Affairs Medical Center, 1481 W 10th St, Indianapolis, IN 46202 (lorrie{at}hsrd.va.iupui.edu).
From the Bowen Research Center, Indiana University, Indianapolis (Ms Mamlin and Drs Melfi, Parchman, Gutierrez, Allen, Dittus, and Freund); the Center for Health Services Research, Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis (Ms Mamlin); the Divisions of General Internal Medicine (Ms Mamlin and Dr Dittus) and Biostatistics (Drs Melfi and Katz), Department of Medicine, the Department of Family Medicine (Drs Parchman and Allen), and the Department of Orthopaedic Surgery (Dr Heck), Indiana University School of Medicine, Indianapolis; Health Services and Policy Research, Lilly Research Laboratories, Indianapolis (Dr Melfi); the Department of Family Medicine, University of Texas at El Paso (Dr Parchman); the Regenstrief Institute for Health Care, Indianapolis (Dr Dittus); and the School of Public and Environmental Affairs, Indiana University, Bloomington (Dr Freund).
REFERENCES
1. National Commission on Arthritis and Related Musculoskeletal Diseases. The Arthritis Plan. Washington, DC: US Dept of Health, Education, and Welfare, Public Health Service, National Institutes of Health; 1976. Out of the Maze: Report to the Congress of the United States; vol 1. US Dept of Health, Education, and Welfare publication NIH 76-1150.
2. US Department of Health and Human Services. National Ambulatory Medical Survey: 1989 Summary. Hyattsville, Md: US Dept of Health and Human Services, Public Health Service, Centers for Disease Control, National Center for Health Statistics; 1992. Series 13: Data from the National Health Survey, No. 110. US Dept of Health and Human Services publication (PHS)92-1771.
3. Lawrence JS. Osteoarthrosis. In: Lawrence JS, ed. Rheumatism in Populations. London, England: Heinemann Medical Books Ltd; 1977:88-115.
4. Mazzuca SA, Brandt KD, Anderson SL, Musick BS, Katz BP. The therapeutic approaches of community based primary care practitioners to OA of the hip in an elderly patient. J Rheumatol. 1991;18:1593-1600.
WEB OF SCIENCE
| PUBMED
5. Holt WS, Mazzuca SA. Prescribing behaviors of family physicians in the treatment of OA. Fam Med. 1992;24:524-527.
PUBMED
6. Mazzuca SA, Brandt KD, Katz BP, Wei L, Stewart KD. Therapeutic strategies distinguish community based primary care physicians from rheumatologists in the management of OA. J Rheumatol. 1993;20:80-86.
WEB OF SCIENCE
| PUBMED
7. Bradley JD, Brandt KD, Katz BP, Kalasinski LA, Ryan SI. Comparison of an anti-inflammatory dose of ibuprofen, an analgesic dose of ibuprofen, and acetaminophen in the treatment of patients with osteoarthritis of the knee. N Engl J Med. 1991;325:87-91.
WEB OF SCIENCE
| PUBMED
8. Callahan CM, Drake BG, Heck DA, Dittus RS. Patient outcomes following tricompartmental total knee replacement. JAMA. 1994;271:1349-1357.
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9. Stross JK, Bole GG. Evaluation of an educational program for primary care practitioners, on the management of OA. Osteoarthritis Rheum. 1985;28:108-111.
10. Freund DA, Dittus RS, Fitzgerald J, Heck D. Assessing and improving outcomes: total knee replacement. Health Serv Res. 1990;25:723-726.
PUBMED
11. Brandt KD, Fife R, Braunstein E, Katz BP. Radiographic grading of severity of knee OA: relation of the Kellgren and Lawrence grade to grade based on joint space narrowing, and correlation with arthroscopic evidence of articular cartilage degeneration. Arthritis Rheum. 1991;34:1381-1386.
PUBMED
12. Felson DT, Naimark A, Anderson J, Kazis L, Castelli W, Meenan RF. The prevalence of knee osteoarthritis in the elderly: the Framingham Osteoarthritis Study. Arthritis Rheum. 1987;30:914-918.
WEB OF SCIENCE
| PUBMED
13. Chang RW, Falconer J, Stulberg SD, Arnold WJ, Manheim LM, Dyer AR. A randomized, controlled trial of arthroscopic surgery versus closed-needle joint lavage for patients with OA of the knee. Arthritis Rheum. 1993;36:289-296.
WEB OF SCIENCE
| PUBMED
14. Berg AD. Variations among family physicians' management strategies for lower urinary tract infections in women: a report from the Washington Family Physician Collaborative Research Network. J Am Board Fam Pract. 1991;4:327-330.
15. Adamson TE, Rodnick JE, Guillion DS. Family physicians and general internists: do they treat hypertension patients differently? J Fam Pract. 1989;29:93-99.
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16. Petitti DB, Grumbach K. Variation in physicians' recommendations about revisit interval for three common conditions. J Fam Pract. 1993;37:235-240.
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