Investigation performed at the Outcomes Unit, Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, NY

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1 1005 COPYRIGHT 2001 BY THE JOURNAL OF BONE AND JOINT SURGERY, INCORPORATED Patients Expectations of Knee Surgery BY CAROL A. MANCUSO, MD, THOMAS P. SCULCO, MD, THOMAS L. WICKIEWICZ, MD, EDWARD C. JONES, MD, LAURA ROBBINS, DSW, RUSSELL F. WARREN, MD, AND PAMELA WILLIAMS-RUSSO, MD, MPH Investigation performed at the Outcomes Unit, Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, NY Background: Patients expectations of medical care are linked to their requests for treatment and to their assessments of outcome and satisfaction. Our goals were to measure patients' preoperative expectations of knee surgery and to develop and test patient-derived knee expectations surveys. Methods: An initial sample of 377 patients (mean age, 54.6 ± 18.2 years; 52% women) was enrolled in the survey-development phase. One hundred and sixty-one (43%) of these patients subsequently underwent total knee arthroplasty; seventy-five (20%), cruciate ligament repair; eighty-five (23%), meniscal surgery; and fifty-six (15%), surgery for another knee condition. Preoperatively, these patients were asked open-ended questions about their expectations of knee surgery. Their responses were grouped with use of qualitative research techniques to generate categories of expectations. Categories were transformed into specific questions and were formatted into two draft surveys, one for patients undergoing total knee arthroplasty and one for patients undergoing other surgical procedures on the knee. A second sample of 163 patients (mean age, 55.1 ± 17.5 years; 49% women) was enrolled in the survey-testing phase, and they completed the draft surveys on two separate occasions to establish test-retest reliability. Items were selected for the final surveys if they were cited by 5% of the patients, if they represented important functional changes resulting from surgery, or if they represented potentially unrealistic expectations. All selected items fulfilled reliability criteria, defined as a kappa (or weighted kappa) value of 0.4, or were deemed to be clinically relevant by a panel of orthopaedic surgeons. Results: From the survey-development phase, a total of fifty-two categories of expectations were discerned; they included both anticipated items such as pain relief and improvement in walking ability and unanticipated items such as improving psychological well-being. Expectations varied by diagnosis and patient characteristics, including functional status. Two final surveys were generated: the seventeen-item Hospital for Special Surgery Knee Replacement Expectations Survey and the twenty-item Hospital for Special Surgery Knee Surgery Expectations Survey. Each required less than five minutes to complete. Conclusions: Patients have multiple expectations of knee surgery in the areas of symptom relief and improvement of physical and psychosocial function, and these expectations vary according to the diagnosis. We developed two valid and reliable surveys that can be used preoperatively to direct patient education and shared decision-making and to provide a framework for setting reasonable goals. Reexamining patients responses postoperatively could provide a way to assess fulfillment of expectations, which is a crucial patient-derived measure of outcome and satisfaction. Across all disciplines of medicine, patients perspectives are being formally included in the process of selecting among treatment options and in assessing results of care 1-4. Patients perspectives can be determined by measuring patient-reported functional status, the importance of symptoms to patients, and their concerns about treatments 5-9. In addition, patients perspectives are ascertained by measuring their expectations of treatments. Patients expectations are particularly important because they are linked to requests for elective and possibly costly treatments and are strongly related to patients assessments of outcome 2,3, A commentary is available with the electronic versions of this article, on our web site ( and on our CD-ROM (call , ext. 140, to order). However, while experts from diverse medical disciplines advocate ascertaining patients expectations 2,3,11-13, few studies have systematically measured patients expectations of orthopaedic procedures 1,10, In addition, most instruments that are currently available to measure expectations of orthopaedic procedures are primarily physician-derived that is, based on clinical knowledge and expertise 13,15,16. Instruments that are patient-derived that is, based on patients perspectives capture a broader array of expectations by including those that may not be attainable or realistic but are still important to patients. In addition, we are not aware of any currently available standardized instruments that measure expectations for many of the most commonly performed operations. The goals of this study were to measure patients expec-

2 1006 Fig. 1 Bar graph showing the mean preoperative American Academy of Orthopaedic Surgeons Lower Limb Core (AAOS-LLC) scores and the mean preoperative Short Form-36 (SF-36) Physical Component Summary (PCS) scores by diagnostic group. On both scales, a score of 0 represents the worst condition and a score of 100 represents the best condition. The patients undergoing total knee arthroplasty (TKA) scored worse on both scales than did the patients in all other diagnostic groups (p = ). In addition, the patients in each diagnostic group scored worse than the general United States population, in which the mean PCS score is 50 (p < 0.001). ACL/PCL = anterior or posterior cruciate ligament. tations of knee surgery and to develop and test the reliability of patient-derived knee surgery expectations surveys in a large sample of patients undergoing various types of operations on the knee. Materials and Methods Phase 1: Developing Draft Surveys Obtaining Baseline Information and Ascertaining Patients Expectations Patients undergoing knee surgery by participating orthopaedists were eligible if they were at least eighteen years old and were fluent in English. Patients were excluded if they had cognitive deficits or were undergoing revision total knee arthroplasty. A total of 377 patients who were scheduled to undergo surgery by one of twelve orthopaedists were enrolled during 1998 and 1999 (see Appendix). Most patients were scheduled to undergo total knee arthroplasty (161; 43%), repair of the anterior or posterior cruciate ligament (grouped together for these analyses) (seventyfive; 20%), or meniscal surgery (eighty-five; 23%). An additional fifty-six patients (15%) were scheduled to have an operation for another condition, including multiligament disorders (one patient), injury of the medial or lateral collateral ligament (two), complete knee dislocation (two), patellofemoral chondromalacia (nine), and osteoarthritis and débridement procedures (forty-two). These 377 patients were interviewed several days before the surgery and asked the open-ended question: What are your expectations of the surgery you are going to have on your knee? The patients were also asked: How important is each expectation? with possible response options ranging from very important to not important. Open-ended responses were analyzed with standard qualitative techniques to generate categories of expectations Categories were named to indicate the major themes that they represented. All open-ended responses from each patient were then reviewed again and were coded according to category. Frequencies of categories were calculated, and a series of multivariate logistic regression equations were set up with categories as dependent variables and with demographic characteristics and functional status scores as independent variables. Demographic information, the ICD-9 (International Classification of Diseases, Ninth Revision) diagnosis, and the patientreported functional status as measured by the American Academy of Orthopaedic Surgeons Lower Limb Core* (AAOS- LLC) and the Medical Outcomes Study Short-Form General Health Survey (SF-36) were obtained from computerized databases maintained at the Hospital for Special Surgery Outcomes Unit Assembly of Draft Surveys Two draft surveys, one for patients undergoing total knee arthroplasty and one for patients undergoing other operations on the knee, were developed. Items included in the draft surveys were selected on the basis of how frequently they were cited and their clinical relevance as determined by a panel of orthopaedists. Specifically, items were selected if they were *The Lower Limb Outcomes Data Collection Instrument and other outcomes instruments in nonprofit patient outcomes research can be obtained by contacting the American Academy of Orthopaedic Surgeons at or at the headquarters office at 6300 North River Road, Rosemont, IL (telephone: ).

3 THE JOUR NAL OF BONE & JOINT SURGER Y JBJS.ORG VO L U M E 83-A N U M B E R 7 J U L Y 2001 PA T I E N T S E X P E C T A T I O N S OF KNEE SURGER Y Fig. 2 The self-administered Hospital for Special Surgery Knee Surgery Expectations Survey is a twenty-item survey including questions about pain, physical function, and psychological expectations. This survey is to be used for patients undergoing operations on the knee other than total knee arthroplasty.

4 THE JOUR NAL OF BONE & JOINT SURGER Y JBJS.ORG VO L U M E 83-A N U M B E R 7 J U L Y 2001 PA T I E N T S E X P E C T A T I O N S OF KNEE SURGER Y Fig. 3 The self-administered Hospital for Special Surgery Knee Replacement Expectations Survey is a seventeen-item survey including questions about pain, physical function, and psychological expectations. This survey is to be used by patients undergoing total knee arthroplasty.

5 1009 cited by 5% of the patients, if they represented important functional changes resulting from surgery, or if they represented potentially inappropriate or unrealistic expectations. Items were phrased as questions with terminology typically used by patients when talking with orthopaedists. Phase 2: Testing Draft Surveys for Reliability Test-Retest Reliability The two draft surveys were then tested to establish test-retest reliability in a new sample of 163 patients who were to undergo surgery by one of fourteen orthopaedists. Patients were identified for this testing phase in the same manner and fulfilled the same eligibility criteria as described above for patients in the survey-development sample. Reliability was measured by giving draft surveys to these new patients on two separate occasions before the surgery and comparing their responses. Specifically, the patients were contacted three to twelve days before the surgery, given the survey during a telephone interview, and then given the same survey several days later, either by telephone or in person in the hospital at the time of the surgery. Test-retest reliability was analyzed with the kappa statistic 24,25. Kappa is a measure of concordance or agreement greater than that due to chance 24,25. Kappa = (observed proportion of agreements chance-expected proportion of agreements)/(1 chance-expected proportion of agreements). It is also possible to calculate a weighted kappa value, which accounts for how far apart responses are, in a frequency table for example. In our study, agreement about the importance of expectations (very important, important, or a little important) was measured with the weighted kappa statistic. Kappa and weighted kappa values can range from 1 (perfect disagreement) to +1 (perfect agreement), and a value of 0 corresponds to agreement that is no better than chance. By convention, values of 0.40 are considered to indicate slight to fair agreement; 0.41 to 0.60, moderate agreement; and >0.60, substantial agreement 25. Phase 3: Generating Final Surveys The selection of items for the final surveys was determined by kappa values and potential clinical relevance. Specifically, an item was retained in the survey if its kappa or weighted kappa value was 0.4. However, items with lower kappa values were assessed individually for possible clinical relevance and prior performance. For example, for items present in both surveys, if the kappa value met the threshold of 0.4 in either survey then that item was retained in both surveys. In addition, a panel of orthopaedists reviewed all items and kappa values to ensure that items with particular clinical relevance (for example, those that possibly represented inappropriate expectations) were retained. Items retained from these analyses formed the questions in the final surveys. Statistical analyses were done with use of the Statistical Analysis System (SAS, Cary, North Carolina) and included means and standard deviations for all continuous variables, frequencies for all ordinal and nominal variables, comparisons of frequencies with the chi-square test, and comparisons of means with the t test 26. In addition, Pearson product-moment correlation coefficients were calculated between pairs of continuous variables, and Spearman rank-order coefficients were calculated between pairs in which at least one variable was ordinal and the other was ordinal or continuous. PROC LOGIST was used for multivariate logistic regression models 26. This study was approved by the Institutional Review Board at the Hospital for Special Surgery. Informed consent for participation was obtained from patients. Results Phase 1: Developing Draft Surveys Patient Characteristics In addition to patient characteristics (see Appendix), mean Lower Limb Core (AAOS-LLC) scores and mean SF-36 Physical Component Summary (PCS) scores were measured (Fig. 1). Patients undergoing total knee arthroplasty scored worse on both scales than did patients in the other groups (p = ). Patients in all groups, especially those undergoing total knee arthroplasty, had worse PCS scores compared with the mean score of 50 in the general United States population (p < 0.001). This finding was anticipated as the PCS is heavily weighted by lower-extremity function. Expectations In total, 1161 expectations were cited, with a mean of 3 ± 1 per patient, and they were grouped into fifty-two categories. The most frequently cited categories in each diagnostic group were determined (see Appendix). Return to sports was a major category for all conditions, with patients mentioning forty-five different sports, the most frequently being tennis, skiing, golfing, jogging, and swimming. Patients undergoing surgery on the anterior or posterior cruciate ligament also listed highdemand sports, such as racquetball (4%), marathon running (3%), rugby (4%), basketball (9%), squash (3%), roller-blading (3%), volleyball (5%), and soccer (5%). Also, 7% of patients undergoing surgery on the anterior or posterior cruciate ligament expected to be able to return to professional sports. Nearly one-third of patients undergoing surgery on the anterior or posterior cruciate ligament expected that, as a result of the surgery, the knee would be back to the way it was before symptoms started. Many of these patients had sustained a specific injury and expected the surgery to reverse the damage caused by the injury. Logistic regression analysis was used to measure relationships between expectations and patient characteristics. Age, gender, education, the SF-36 PCS score, and the AAOS-LLC score were considered to be independent variables. In the entire sample, more women than men expected improvement in walking ability (57% compared with 29%, p = 0.001) and more men than women expected improvement in sports performance (51% compared with 40%, p = 0.03). Younger patients were more likely to expect improvement in sports performance and for the knee to be back to the way it was before symptoms started (p = ), whereas older patients were more likely to expect pain relief (p = 0.04) and improved walking ability (p =

6 ). Patients with less education were more likely to expect psychological improvement (p = 0.01) and pain relief (p = 0.003), and patients with more education were more likely to expect improvement in sports performance (p = ). Patients with a worse PCS score were more likely to expect a psychological benefit, improvement in walking ability, and to be able to return to work (p 0.03). Patients with better PCS and AAOS-LLC scores were more likely to expect improvement in sports performance, whereas patients with a worse AAOS-LLC score were more likely to expect improvement in walking ability (p = ). Assembly of Draft Surveys There were significant differences with regard to frequencies of expectations in eleven of the twenty-one categories between patients undergoing total knee arthroplasty and those undergoing other operations on the knee (p 0.02) (see Appendix). Therefore, two draft expectations surveys were developed, one for patients undergoing total knee arthroplasty and one for patients undergoing other general knee procedures. For each survey, items were selected on the basis of their clinical relevance and how frequently they had been cited in this study. In addition, because there was variation in expectations related to pain relief and improvement in walking ability, we modified these items to assess the magnitude of improvement expected for example, how far patients expected to be able to walk. A distinction was also made between recreational and professional sports in the survey for patients undergoing general knee surgery. The response format for each item asks patients whether they have that expectation and, if so, how important it is. If they do not have the expectation, patients indicate either that the item does not apply to them or that the item does apply but is not something that they expect. Phase 2: Testing Draft Surveys for Reliability Patient Characteristics The demographic characteristics, functional status, and orthopaedic characteristics of the 163 patients enrolled in the reliability-testing phase were similar to those of the patients in the survey-development phase (see Appendix). Patients undergoing total knee arthroplasty were older than those in the other groups and were also more likely to be women, to be retired, and to have a worse functional status (p < 0.003). Test-Retest Reliability The first interview was conducted at a mean of 6.0 ± 2.0 days (range, three to twelve days) before the surgery and the second interview, at a mean of 5.1 ± 1.7 days (range, three to eleven days) after the first interview. All first interviews were done by telephone; 37% of the second interviews were done by telephone, and the remaining were done in the hospital on or close to the day of the surgery. Surveys took less than five minutes to complete. All patients agreed to participate in the second interview, indicating to us that these surveys are acceptable to patients. The first and second interviews were done by the same interviewer for 79% of the patients, and they were done by different interviewers for 21%. Phase 3: Generating Final Surveys Knee Surgery Expectations Survey Kappa values ranged from 0.4 to 0.8 for almost all items from the draft general knee surgery expectations survey (see Appendix). Only one item, expecting to have improved knee strength, had kappa and weighted kappa values of <0.4. This item was not considered to have any clinical relevance and therefore was discarded. In addition to the pain and walking items listed, patients were also asked how much pain relief they expected (nearly 55% expected complete pain relief, kappa = 0.5) and how far they expected to be able to walk (nearly 85% expected to be able to walk >1 mi [>1.6 km], kappa = 0.5). From these analyses we generated the final version of the Hospital for Special Surgery Knee Surgery Expectations Survey, composed of twenty questions and requiring less than five minutes to complete (Fig. 2). Knee Replacement Expectations Survey Kappa or weighted kappa values ranged from 0.4 to 0.8 for most items of the draft total knee arthroplasty expectations survey (see Appendix). Expecting improvement in walking was cited by all patients during both interviews and therefore the kappa value was numerically uninterpretable. Because of the prevalence of this item, it was retained in the final version. Expecting the knee to be back to the way it was before symptoms started had kappa and weighted kappa values of 0.3 and was eliminated. It is possible that this item did not perform well because patients undergoing total knee arthroplasty typically have symptoms for many years before the surgery. Expecting improvement in daily activities had a low kappa value of 0.1 and a weighted kappa of 0.3. We decided to retain this item because it has clinical relevance and it performed well in the general knee surgery expectations survey. In addition to the pain and walking items listed, nearly 52% of patients undergoing total knee arthroplasty expected complete pain relief (kappa = 0.5) and nearly 65% expected to be able to walk >1 mi (kappa = 0.7). From these analyses, we generated the final version of the Hospital for Special Surgery Knee Replacement Expectations Survey, composed of seventeen questions and also requiring less than five minutes to complete (Fig. 3). Discussion he results of this study demonstrate that patients have mul- expectations of knee surgery and that these expecta- Ttiple tions vary by diagnosis, patient characteristics, and functional status. Using a large sample of patients, we developed and tested two knee surgery expectations surveys a seventeen-item survey for patients undergoing total knee arthroplasty and a twenty-item survey for patients undergoing other types of knee surgery. The items in the surveys are presented in simple, brief terms and address symptom-related, functional, and psychosocial expectations. The surveys took less than five minutes to complete and were well accepted by the patients.

7 1011 These surveys have several possible uses in daily practice, especially if patients complete them at the time of their evaluation by the orthopaedist. First, they provide a simple way to obtain a more comprehensive evaluation that would otherwise require a lengthy interview. Second, they provide a way for patients to specifically state what they anticipate from surgery; this is particularly useful for patients who would otherwise express their goals in vague, nonspecific terms. Third, they provide the orthopaedist with a written template to guide a formal discussion about what are realistic and unrealistic goals for each patient. In addition, the orthopaedist can add comments to the survey to reflect specific discussion and recommendations. Fourth, if the survey is included in the patient s chart, it can be referred to at the time of long-term postoperative follow-up as a way for patients and orthopaedists to jointly assess fulfillment of expectations and for patients to remember that these items were addressed preoperatively. This may be particularly helpful for patients who are dissatisfied with the outcome. A major strength of these instruments is that they were patient-derived that is, all items were determined by patients, not set a priori by physicians. This is important not only because of the intrinsic face validity of patient-derived instruments but also because patient-derived instruments can include a broad spectrum of items that might not be readily apparent to physicians, such as expecting psychological improvement. In addition, physician-derived instruments usually do not include expectations that are probably not attainable but are still held by patients. For example, in our study many patients expected the knee to recover to its preinjury state and many patients who were to undergo total knee arthroplasty expected complete pain relief. Another strength of these instruments is that a panel of orthopaedists reviewed the surveys to ensure content validity and to phrase questions in words typically used by patients. The orthopaedic panel also separated certain knee-function expectations into distinct survey items, which had initially been considered together. Squatting after total knee arthroplasty is an example of a knee function that was selected to be a distinct item because a patient s response that it was expected would generate specific discussions with the patient regarding its likelihood postoperatively. Valid and reliable questionnaires in a written format, such as the surveys developed in this study, facilitate the important task of obtaining and recording patients expectations 3. Measuring patients expectations is necessary for various reasons. For example, knowing these expectations helps physicians to provide more focused clinical care, highlights areas for patient education, and promotes shared decision-making when several treatment options are available 2,3. Involving patients in their care by discussing expectations has also been shown to increase patients adherence to recommendations 1,27,28. In addition, fulfillment of expectations is associated with patients assessment of outcome and satisfaction, two measures that may justify elective orthopaedic procedures even if they are costly 1-3. Within orthopaedics, several types of expectations have been studied. For example, studies of total hip arthroplasty have assessed the relationship between fulfillment of expectations and satisfaction with the outcome 10,15,16,29. Other investigators have considered the influence of orthopaedists expectations on patients with a hip fracture, the ambitiousness of the expectations of patients undergoing surgery for the treatment of lumbar spinal stenosis, and the level of concern about not knowing what to expect among patients undergoing total hip or total knee arthroplasty 1,9,28. There are several limitations to this study. First, the participants were all patients in a tertiary-care orthopaedic institution and therefore may not be representative of other patient populations. Second, some patients were interviewed in the hospital on the day of the surgery, when their responses may have been affected by apprehension and anxiety. Third, although the surveys were intended to be self-administered, they were tested during telephone and in-person interviews. This was done to maximize response rates during the test-retest phase. In conclusion, two valid and reliable instruments have been created for patients undergoing knee surgery: the seventeenitem Hospital for Special Surgery Knee Replacement Expectations Survey and the twenty-item Hospital for Special Surgery Knee Surgery Expectations Survey. These instruments have several possible uses in both clinical practice and research, and they should enhance shared decision-making and our ability to assess outcomes and patient satisfaction following these procedures. NOTE: The authors thank the orthopaedic surgeons in the Adult Arthroplasty Service and the Sports Medicine Service at the Hospital for Special Surgery for their participation. Appendix Tables showing demographic characteristics of the patients in the survey-development sample, the most frequently cited expectations by diagnosis, demographic and orthopaedic characteristics of the patients in the survey-testing sample, and the test-retest reliability of the draft knee surgery expectations survey and the draft total knee arthoplasty expectations survey are available with the electronic versions of this article, on our web site ( and on our CD- ROM (call , ext. 140, to order). Carol A. Mancuso, MD Thomas P. Sculco, MD Thomas L. Wickiewicz, MD Edward C. Jones, MD Laura Robbins, DSW Russell F. Warren, MD Pamela Williams-Russo, MD, MPH Hospital for Special Surgery, 535 East 70th Street, New York, NY No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. No funds were received in support of this study. This study was conducted while C.A. Mancuso was a Robert Wood Johnson Generalist Physician Faculty Scholar. Read at the Annual Meeting of the American Academy of Orthopaedic Surgeons, Orlando, Florida, March 16, 2000.

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