Efficacy of Total Knee Arthroplasty in Elderly Patients With Locomotive Syndrome: a Prospective Longitudinal Study

Efficacy of Total Knee Arthroplasty in Elderly Patients With Locomotive Syndrome: a Prospective Longitudinal Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Efficacy of Total Knee Arthroplasty in Elderly Patients With Locomotive Syndrome: a Prospective Longitudinal Study Toru Ogata, Keiko Yamada, Hiromasa Miura, Kazunori Hino, Tatsuhiko Kutsuna, and 18 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-841197/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: To preserve the ability to perform physical activities among the elderly, the concept of locomotive syndrome and its evaluation method, the locomotive syndrome risk test, have been applied in an integrated manner to capture the decline in mobility resulting from musculoskeletal disorders. During treatment, physicians can use the locomotive syndrome risk test to evaluate the impact of each therapy such as total knee arthroplasty for knee osteoarthritis, a common disorder found in locomotive syndrome. The purpose of this study was to evaluate the impact of total knee arthroplasty in the elderly with respect to locomotive syndrome. Methods: A total of 111 patients were registered at six hospitals prior to total knee arthroplasty and postoperatively followed up for 1 year. Three components of the locomotive syndrome risk test (the two-step test, stand-up test, and geriatric locomotive function scale-25) were assessed together with the EuroQol-5 Dimension scores pre- and postoperatively. Results: Post surgery, all three components of the locomotive syndrome risk test as well as the EuroQol-5 Dimension utility score showed significant improvements from the baseline (two-step test, 1.01±0.25 to 1.12±0.21; stand-up test, 2.02±1.14 to 2.38±1.20; geriatric locomotive function scale-25, 38.3±15.8 to 18.7±16.6, mean ± standard deviation). The ratio of stage 3 locomotive syndrome patients (progressed stage of decrease in mobility, restricting social engagement) reduced from 82.3% to 33.9% postoperatively. There was no significant difference in the degree of change in the three test scores between the younger (60-74 years) and older (≥75 years) age groups. Conclusions: We found that total knee arthroplasty has a major impact in preventing the progression of locomotive syndrome in patients with knee osteoarthritis. The locomotive syndrome risk test is a feasible tool for longitudinal evaluation of patients with musculoskeletal diseases of varying severity and with multiple symptoms. Trial registration: This study was registered as UMIN000023595 (10/08/2016) Geriatrics & Gerontology total knee arthroplasty locomotive syndrome elderly patients longitudinal study health problems Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Managing the health problems of the aging population is now a common medical challenge in many countries including Japan where the elderly (older than 65 years) constitute more than 28% of the total population [ 1 , 2 ]. In these countries, health policies are directed at prolonging the period during which the elderly can live independently without care from others. According to Japanese governmental statistics, the three leading causes of disabilities which compel the elderly to avail the services of the long-term care insurance (LTCI) system, a governmental policy to provide suitable individual care services for the disabled elderly, are cerebrovascular diseases, dementia, and musculoskeletal diseases [ 3 ]. Therefore, the management of problems associated with aging with respect to the musculoskeletal system is of social interest, and this prompted the Japanese Orthopaedic Association to propose the concept of the locomotive syndrome in 2007 [ 4 ]. Locomotive syndrome is defined as a condition of decreased mobility in activities essential to daily life such as walking, standing up, and climbing stairs, resulting from impairment of the locomotive organs [ 5 ]. The severity of locomotive syndrome is evaluated using the locomotive syndrome (LS) risk test, a screening tool which consists of three tests: the two-step test, stand-up test, and 25-Question Geriatric Locomotive Function Scale (GLFS-25) [ 6 , 7 ]. The simplicity and feasibility of these tests enable them to be used as a screening tool in various types of surveys focusing on not only the disabled elderly but also the general population [ 8 – 10 ]. Knee osteoarthritis (KOA) is a common pathological condition observed in patients with locomotive syndrome [ 11 , 12 ]. Its painful symptoms prevent the active lifestyle typical of middle-aged people. In the later stages of the disease, the activities of daily living of the patients are also impaired [ 13 , 14 ]. Total knee arthroplasty (TKA) sufficiently improves both pain and knee function of KOA patients which are commonly evaluated by knee-specific patient-reported outcome measures such as the Knee Society Score and the Japanese Knee Osteoarthritis Measure [ 15 – 17 ]. As the survival rate of implants has improved, the current therapeutic challenge is to maintain long term post-operative physical activities. However, several studies have revealed that the locomotive functions gradually declined after surgery even without implant-related problems [ 18 , 19 ]. This may be due to the degenerative changes in musculoskeletal organs other than knees since most Japanese people undergo initial TKA surgeries in their 70s [ 20 ]. Therefore, patients opting for TKA should also be evaluated using an integrated measurement tool, such as the LS risk test, for musculoskeletal function and difficulties in daily living. While the application of the test has been reported in surgical treatments for hip osteoarthritis and lumbar canal stenosis, it has not been evaluated in patients undergoing TKA surgeries [ 21 , 22 ]. Therefore, the purpose of this study was to evaluate the pre- and post-operative condition of patients undergoing TKA for KOA using the LS risk test to assess their condition from the point of view of integrated care in the management of musculoskeletal disorders. Methods Study participants For this observational cohort study, patients who were scheduled to undergo TKA surgery were registered at six hospitals in a prospective manner. The inclusion criteria were as follows: (1) patients aged ≥ 60 and < 90 years and (2) those undergoing TKA for KOA in one or both knees. Those with severe comorbidities, such as chronic renal disease and chronic heart failure, were excluded. All subjects provided written informed consent prior to participation. The study was approved by the IRB of the authors’ affiliated institutions and conducted in accordance with the principles of the Declaration of Helsinki. Data collection The initial data, LS risk test scores, and 5-level EuroQol-5 Dimension (EQ-5D-5L) scores together with the demographic data were collected by a medical specialist within 3 months before the surgery. The patients were instructed to visit the hospital 1 year after surgeries to undergo similar evaluations as the one stated above. For patients who underwent TKA for both knees consecutively, the follow-up evaluations were scheduled 1 year after the last surgery. Locomotive syndrome risk test The locomotive syndrome risk test consists of one patient-reported outcome measure: the GLFS-25 and two performance tests: the two-step and stand-up tests. These tests were performed as described in previous papers [ 7 ]. To summarize, the GLFS-25 included 25 questions each of which had a 0–4 graded Likert scale about mobility-related difficulties in daily life, with the higher grades representing a deteriorating health condition. As for the two-step test, patients began from the standing position and then stepped forward as far as they could with the right and left steps in succession. The maximum distance covered by the two steps was divided by the patients’ heights for standardization. In the stand-up test, patients were asked to sit on boxes that were 10 to 40 cm high and then stand up without any support using either one or both legs. Successful trials were recorded. Statistical analysis To compare the demographic background between the two groups, we used Fisher’s exact test for categorical variables and the t-test for continuous variables. The differences in the pre- and post-operative test scores (LS risk test and EQ-5D) were compared using the paired t-test because of its approximately normal distribution (Supplementary Fig. 1). We used multiple imputation to handle the missing data in the GLFS-25 scores because of its relatively high percentage (22% of follow-up patients) [ 23 ]. We imputed by fully conditional specification method using discriminant function with Proc MI in SAS (SAS Institute, Cary, NC, USA) [ 24 ]. The imputation procedure used each score of all 25 questions of GLFS-25 because of their close association with the missing GLFS-25 value. The results across 20 imputed data set were combined by averaging and standard errors were adjusted according to within and between imputation variability [ 25 ] The linear mixed-effects model with an unstructured covariance matrix for residuals was used to examine whether the pre- and post-operative change in each test score was different between the age groups. To control other possible confounders, we included the gender, number of TKAs (bilateral/unilateral), and body mass index in the model. We also compared the baseline test scores between patients who were followed up and those who were lost to follow-up. A p-value of less than 0.05 was considered statistically significant. All statistical analyses were performed using SAS 9.4 (SAS Institute, NC, US). Results A total of 111 patients were enrolled in the study, 87 of whom completed the follow-up assessments. The follow-up period was 406.4 ± 102.5 (mean ± standard deviation) days after surgery. The age of the patients at the time of surgery was 74.6 ± 5.9 years, ranging from 60 to 88 years. The other demographic data are presented in Table 1. The pre-operative evaluation showed that the mean scores of the two-step test, stand-up test, and GLFS-25 were 1.01 ± 0.25, 2.02 ± 1.14, and 38.3 ± 15.8, respectively (Table 2). The details of the GLSF-25 scores are shown in Fig. 1 , presenting the average scores for each item. The GLFS-25 questionnaire contains several items associated with “pain” (Q1: neck and upper limb pain, Q2: back and buttock pain, Q3: leg pain, and Q4: pain in motion). While the item for pain in the legs (Q3) had a higher average score than others, 48.1% of participants experienced moderate or severe pain in other parts of their bodies. Similar scores were observed in all three tests irrespective of whether the patients had undergone TKA for one or both knees. A significant difference was observed in the two-step test scores between those who dropped out and those who completed the follow-up. However, the results of the GLFS-25 and stand-up tests were similar between them (Supplementary Table 1). Table 1 The demographic background of the patients Men (n=23) Women (n=88) Total (n=111) Age, mean ± SD 74.0 ± 6.7 74.7 ± 5.7 74.6 ± 5.9 BMI, mean ± SD 26.2 ± 2.6 26.5 ± 4.1 26.4 ± 3.8 Bilateral operation, n(%) 2 (8.7) 14 (15.9) 16 (14.4) Medication # , n(%) Hypertension 14 (73.7) 59 (75.6) 73 (75.3) Diabetes Melltius 2(10.5) 15 (19.2) 17 (17.5) Nsaids 8(42.1) 16 (20.5) 24 (24.7) Osteoprosis* 0 (0.0) 19 (24.4) 19 (19.6) Steroid 0 (0.0) 3 (3.9) 3 (3.1) Depression 0 (0.0) 4 (5.1) 4 (4.1) *p<0.05, significant sex difference using Fisher's exact test; BMI=body mass index. #medication (n = 97). Table 2 Pre and post-operative scores of locomotive syndrome risk test and EQ-5D Pre-operation 1-year post operation P-value* N Mean (SD) Median (IQR) Mean (SD) Median (IQR) Two-step test score 80 1.01 (0.25) 1.06 (0.90-1.17) 1.12 (0.21) 1.16 (1.02-1.27) <0.001 Stand-up test score 83 2.02 (1.14) 2 (1-3) 2.38 (1.20) 2 (2-3) 0.0069 Total GLFS-25 score 68 38.3 (15.8) 37 (26-48) 18.7 (16.6) 13 (6.5-25) <0.001 EQ-5D utility score 83 0.58 (0.14) 0.59 (0.53-0.67) 0.77 (0.17) 0.75 (0.67-1.0) <0.001 SD = standard deviation; IQR = interquatile range; GLFS-25 = the 25-question geriatric locomotive function scale; EQ-5D = EuroQol 5 dimensions * Paired t-test The LS risk test and EQ-5D utility scores before surgery and at follow-up are shown in Fig. 2 and Table 2. Significant improvements were observed in all three components of the LS risk test as well as in the EQ-5D utility scores. The improvements in the mean values were 0.11 for the two-step test, 0.36 for the stand-up test, 19.6 for the GLFS-25, and 0.19 for EQ-5D (Table 2). For the GLFS-25, the changes in each item were examined using the mean values. While most of the items showed improvement after the surgery, a marked improvement (improvement of > 1.5 points) was observed in Q3 (leg pain) and Q13 (difficulty in walking briskly). On the other hand, no change was observed in Q8 (difficulty in putting on and taking off shirts) (Fig. 1 ). The severity of locomotive syndrome is summarized by the locomotive syndrome staging criteria: normal, stage 1 (starting stage of decrease in mobility defined by two-step test score < 1.3, or stand-up test score ≤ 4, or GLFS-25 score ≥ 7), and stage 2 (progressing stage of decrease in mobility defined by two-step test score < 1.1, or stand-up test score ≤ 2, or GLFS-25 score ≥ 16) [ 8 ]. Recently, the more severe condition of decrease in mobility was defined as stage 3 (progressed stage of decrease in mobility, restricting social engagement defined by two-step test score < 0.9, or stand-up test score ≤ 1, or GLFS-25 score ≥ 24) to recommend visiting medical specialists [ 26 ]. In the preoperative survey, the ratio of the patients who were categorized as stage 3, 2, and 1 is 82.3%, 16.1%, and 1.6% respectively. The conversion of the stages of locomotive syndrome after surgery is presented in Fig. 3 . The ratio of stage 3 patients reduced from 82.3–33.9% post-operatively, while the ratio of stage 2 patients increased from 16.1–45.2%. Since locomotive syndrome tends to progress with age, patients undergoing TKA at older ages were speculated to have a worse clinical course. While patients in the older age group showed higher GLFS-25 scores indicating a poor condition both pre- and post-operatively, there was no interaction between the age group and the pre/post-operative time period (Table 3 ). This result indicated that age (60–74 years or ≥ 75 years) did not affect the degree of improvement afforded by the TKA surgery. Figure 4 illustrates the parallel trend of the LS risk test between the 60–74 and ≥ 75 age groups. Table 3 The estimated effect of age groups on the change of pre-and post operative test scores, using linear mixed effects model Outcomes and fixed effects Estimate SE df t value Pr >|t| Two-step test score Period (post operation) 0.124 0.028 80 4.430 < .0001 Sex (male) 0.177 0.048 80 3.670 < .0001 Age group (age ≥ 75) -0.087 0.052 80 -1.680 0.098 Number of TKA (bilateral) 0.013 0.051 80 0.260 0.792 BMI (bmi ≥ 25) -0.059 0.041 80 -1.430 0.156 Period × age group -0.029 0.041 80 -0.710 0.480 Stand-up test score Period (post operation) 0.198 0.195 80 1.010 0.313 Sex (male) 0.615 0.257 80 2.400 0.019 Age group (age ≥ 75) -0.401 0.251 80 -1.600 0.113 Number of TKA (bilateral) -0.402 0.268 80 -1.500 0.138 BMI (bmi ≥ 25) -0.399 0.220 80 -1.820 0.073 Period × age group 0.371 0.286 80 1.300 0.199 Total GLFS-25 score Period (post operation) -18.612 2.444 78 -7.620 < .0001 Sex (male) -9.172 3.668 78 -2.500 0.015 Age group (age ≥ 75) 9.152 3.500 78 2.620 0.011 Number of TKA (bilateral) -5.003 3.893 78 -1.290 0.203 BMI (bmi ≥ 25) 3.729 3.170 78 1.180 0.243 Period × age group -1.688 3.536 78 -0.480 0.635 EQ-5D utility score Period (post operation) 0.208 0.028 80 7.320 < .0001 Sex (male) 0.066 0.033 80 2.010 0.047 Age group (age ≥ 75) -0.045 0.032 80 -1.410 0.161 Number of TKA (bilateral) 0.018 0.034 80 0.510 0.600 BMI (bmi ≥ 25) -0.034 0.028 80 -1.230 0.224 Period × age group -0.025 0.042 80 -0.590 0.557 Outcomes are three locomotive syndrome risk test scores and EQ-5D utility score. Each estimate reflects an association between each outcome (test score) and independent variables, adjusting for all other variables in the model. Reference = period (pre-operation), female (sex), age < 75(age group), unilateral TKA (number of TKA), BMI (bmi < 25) SE = standard error; GLFS-25 = the 25-question geriatric locomotive function scale; EQ-5D = EuroQol 5 dimensions; BMI = body mass index. In total, 16 participants (14.4%) underwent bilateral knee operation during the survey period. The magnitude of improvement was not affected by the number of TKAs (Table 3 ). Discussion In this study, we described the condition of the musculoskeletal organs in patients undergoing TKA by the LS risk test and evaluated the changes afforded by the surgery. Our data clearly showed that most of the patients belonged to locomotive syndrome stage 2 or 3 pre-operatively (98.4%), and TKA improved their condition in terms of patient-oriented outcome measures and objective function tests. A recent report on the reference values of the LS risk test in a healthy population showed that the median GLFS-25 scores for those aged between 65 and 69, and 75 and 79 were 4 and 6, respectively [ 10 ]. On the other hand, Yamada et al. reported that the mean GLFS-25 score for the elderly who availed the services of the LTCI system was 33.8 [ 9 ]. In our study, the average preoperative GLFS-25 score was 38.3 suggesting that the pre-operative condition of patients undergoing TKA was similar to the condition of individuals who need care and support and have a risk of dependency. The significant improvement in the GLFS-25 and other tests after TKA confirmed that joint replacement surgeries have a beneficial impact not only on knee pain and function but also on the improvement of general musculoskeletal function. The selection of the optimal age is critical for successful surgeries [ 27 , 28 ]. Our study showed that the degree of improvement provided by TKA is equivalent between the older (≥ 75 years) and younger (64–74 years) age groups, suggesting that surgery is expected to improve the ability to perform daily activities even in older patients. However, it should be noted that the pre- and post-operative GLFS-25 scores were higher in the older age group than that of the younger age group (mean post-operative GLFS-25 score, ≥ 75 age group, 21.8 ± 19.4 vs. 60–74 age group, 16.0 ± 13.5). As the number of people using the LTCI services increases after the age of 75, the residual dysfunction and difficulty in daily activities among the older age group patients should be carefully monitored so that their physical condition can be maintained through suitable lifestyle modifications and if necessary, treatments. One of the advantages of the LS risk test is its ability to evaluate the condition of the musculoskeletal organs in an integrated manner. In our study, 48.1% of patients had moderate or severe pain in sites other than the leg, suggesting that the patients suffered not only from KOA but also from other musculoskeletal disorders such as degenerative spinal disorders and upper limb pain. As previously reported, many patients tend to have multiple bone and joint diseases, and the difficulties faced by them in daily life reflect the summation of all these symptoms [ 11 , 29 , 30 ]. Using the LS risk test, the physician can gauge the overall impact of the disease on patients’ daily living and the function of their locomotive organs. The integrated difficulties in the daily living of patients with multiple musculoskeletal problems have been evaluated using various quality of life assessment scales such as EQ-5D, a well-established scale that consists of five questionnaires, assessing the mobility, self-care, activity, pain, and anxiety [ 31 ]. Because Seichi et al. reported that the GLFS-25 score correlated well with the EQ-5D score, the GLFS-25 has a potential to be used as a quality of life outcome measure for patients with musculoskeletal diseases as demonstrated in the current study where the two scales showed similar trends [ 6 ]. While the LS risk test questionnaire form takes longer to complete which is a disadvantage, its wide range of scores provides sufficient sensitivity to detect changes during longitudinal observation. Therefore, the LS risk test would be useful for a long-term follow-up analysis in patients undergoing conservative treatment and/or musculoskeletal surgeries in organs other than the knee joints. In future, the data accumulated from the LS risk test during the long-term follow-up will help physicians develop therapeutic strategies for managing the mobility function of each patient. Our study has several limitations. First, we excluded patients with severe comorbidities from the study. Therefore, the current data should be considered as information conceived from typical clinical cases of KOA. In cases with severe comorbidities, the score of the LS risk test would be influenced by conditions other than those affecting the bones and joints and would need to be interpreted more cautiously. Second, since the minimum clinically important difference (MCID) of the LS risk test has not been established, the efficacy of treatment in each case cannot be determined. Further studies are required to determine the MCID to identify the factors that may have an impact on the efficacy of treatment. Finally, a fraction of patients was lost to follow-up. The lower score observed in the two-step test in the lost to follow-up group suggests the possibility that patients who had poor mobility after surgery could not turn up for the follow-ups. As this is an inherent limitation in longitudinal studies related to mobility disorders, an alternative method of data collection from patients who have restricted mobility is required in future studies. Conclusions In conclusion, we observed that the LS risk test was useful in evaluating patients undergoing TKA. In the baseline assessment, the scores revealed that the physical condition of the patients was similar to that of individuals who required assistance for their daily activities. These tests can also be used to describe changes after surgery, providing qualitative information about difficulties in daily life and functions. The locomotive syndrome risk test is a feasible tool for evaluating patients with musculoskeletal diseases of varying severity and with multiple symptoms. Abbreviations LTCI: long-term care insurance LS: locomotive syndrome GLFS-25: 25-Question Geriatric Locomotive Function Scale KOA: knee osteoarthritis TKA: total knee arthroplasty EQ-5D-5L: 5-level EuroQol-5 Dimension MCID: minimum clinically important difference Declarations Ethics approval and consent to participate: All subjects provided written informed consent prior to participation, which was approved by the ethical committee of the University of Tokyo (No. 11256) as well as by each hospital. Consent for publication: Not applicable Availability of data and materials: The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Competing interests: All authors declare that they have no conflicts of interest. Funding: This study was supported by JOA-Subsidized Science Project Research 2015-1. The funder had no role in collection, analyses, and interpretation of the data, nor decision to submit results. Authors' contributions: TO, KN and ST designed the study. KY and YI performed statistical analyses. HM and KO established data collecting systems. KH, TK, KW, TK, YI, YY, TS, SM, SK, MW, TT, MT, TI, HM, SI and YM collected data and interpreted the patient data. TO and KY wrote the manuscript. All authors read and approved the final manuscript. Acknowledgements: Not applicable References United Nations. World Population Ageing 2017 Highlights [ https://www.un.org/en/development/desa/population/publications/pdf/ageing/WPA2017_Highlights.pdf ] Cabinet Office, Government of Japan. Annual Report on the Ageing Society. 2019 [ https://www8.cao.go.jp/kourei/whitepaper/w-2019/gaiyou/pdf/1s1s.pdf ] Ministry of Health, Labour and Welfare. Long-Term Care Insurance System of Japan [ http://www.mhlw.go.jp/english/policy/care-welfare/care-welfare-elderly/dl/ltcisj_e.pdf ] Nakamura K: A "super-aged" society and the "locomotive syndrome" . J Orthop Sci 2008, 13 (1):1-2. 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The locomotive syndrome staging criteria (Japanese) [ https://locomo-joa.jp/assets/pdf/locomo-testjudge.pdf ] Kondo K, Tanaka T, Hirota Y, Kawamura H, Miura H, Sugioka Y, Inoue H, Kurosaka M, Yamashita T, Shirata K et al : Factors associated with functional limitation in stair climbing in female Japanese patients with knee osteoarthritis . J Epidemiol 2006, 16 (1):21-29. Chang CB, Yoo JH, Koh IJ, Kang YG, Seong SC, Kim TK: Key factors in determining surgical timing of total knee arthroplasty in osteoarthritic patients: age, radiographic severity, and symptomatic severity . J Orthop Traumatol 2010, 11 (1):21-27. Imagama S, Ando K, Kobayashi K, Seki T, Hamada T, Machino M, Ota K, Tanaka S, Morozumi M, Kanbara S et al : Impact of comorbidity rates of lumbar spondylosis, knee osteoarthritis, and osteoporosis on physical QOL and risk factors for poor physical QOL in middle-aged and elderly people . Mod Rheumatol 2020, 30 (2):402-409. Rat AC, Guillemin F, Osnowycz G, Delagoutte JP, Cuny C, Mainard D, Baumann C: Total hip or knee replacement for osteoarthritis: mid- and long-term quality of life . Arthritis Care Res (Hoboken) 2010, 62 (1):54-62. Conner-Spady BL, Marshall DA, Bohm E, Dunbar MJ, Loucks L, Al Khudairy A, Noseworthy TW: Reliability and validity of the EQ-5D-5L compared to the EQ-5D-3L in patients with osteoarthritis referred for hip and knee replacement . Qual Life Res 2015, 24 (7):1775-1784. Additional Declarations No competing interests reported. Supplementary Files KOAFigureSup1.pptx locomoTKASupTable1.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Ogata","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA60lEQVRIiWNgGAWjYFADHgbGBwwMEhCOBF6FIJAAZPAwMBuQrIUNn0IEsGdvPvzi5w87BnueM2bVvDkWeQzshx8wWO7AYwvPsTTLnoRkBh7eHrPbvNskihl40gwYJM/g0SKRY2bAk8Bc38PPA9aS2MCQw8Ag2YZfi+GfhHoGHqCWYrAW/jcEtRg/5kk4DHYYM1iLBCFbzhxLY5ZJOw5iFEvOBWppk3hmcACfX9jbmw9/fGNTzcDek7zxw9ttdYn9/MkPH0viCTEggEUHhwGEC8SHJRvwamH+ALXwAVyI8SN+LaNgFIyCUTCyAAAOF0TKuWzUBQAAAABJRU5ErkJggg==","orcid":"","institution":"University of Tokyo Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Toru","middleName":"","lastName":"Ogata","suffix":""},{"id":50863773,"identity":"3df11e2d-7f74-4336-866f-4ca70f769ea5","order_by":1,"name":"Keiko Yamada","email":"","orcid":"","institution":"University of Tokyo Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Keiko","middleName":"","lastName":"Yamada","suffix":""},{"id":50863775,"identity":"7cc121c3-9443-4baf-ab3a-af11ce38e629","order_by":2,"name":"Hiromasa Miura","email":"","orcid":"","institution":"Ehime University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hiromasa","middleName":"","lastName":"Miura","suffix":""},{"id":50863777,"identity":"6036a7c3-007e-41a5-9f73-0cb27e2f8f57","order_by":3,"name":"Kazunori Hino","email":"","orcid":"","institution":"Ehime University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Kazunori","middleName":"","lastName":"Hino","suffix":""},{"id":50863778,"identity":"ed8d80e5-815a-4a25-9d8c-97c9602e9c62","order_by":4,"name":"Tatsuhiko Kutsuna","email":"","orcid":"","institution":"Ehime University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tatsuhiko","middleName":"","lastName":"Kutsuna","suffix":""},{"id":50863780,"identity":"5123e221-55bb-4fe4-8363-7255bf032978","order_by":5,"name":"Kunihiko Watamori","email":"","orcid":"","institution":"Ehime University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Kunihiko","middleName":"","lastName":"Watamori","suffix":""},{"id":50863782,"identity":"b600f2bf-2534-45b7-bf92-eb8a2e5c4e21","order_by":6,"name":"Tomofumi Kinoshita","email":"","orcid":"","institution":"Ehime University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tomofumi","middleName":"","lastName":"Kinoshita","suffix":""},{"id":50863783,"identity":"927929a8-6a7d-4a19-81a2-b8095d8c623c","order_by":7,"name":"Yasuyuki Ishibashi","email":"","orcid":"","institution":"Hirosaki University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yasuyuki","middleName":"","lastName":"Ishibashi","suffix":""},{"id":50863784,"identity":"50001f92-7e1b-4819-a3d0-f5fa1be1a7ee","order_by":8,"name":"Yuji Yamamoto","email":"","orcid":"","institution":"Hirosaki University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yuji","middleName":"","lastName":"Yamamoto","suffix":""},{"id":50863785,"identity":"e50739ba-2343-4b1d-b242-0c3a3751f3c7","order_by":9,"name":"Tomoyuki Sasaki","email":"","orcid":"","institution":"Hirosaki Memorial Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tomoyuki","middleName":"","lastName":"Sasaki","suffix":""},{"id":50863786,"identity":"5c4e5375-1819-4f74-a370-ef99d83ef60f","order_by":10,"name":"Shuichi Matsuda","email":"","orcid":"","institution":"Kyoto University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shuichi","middleName":"","lastName":"Matsuda","suffix":""},{"id":50863787,"identity":"c4af5832-31ff-4056-9a43-d322e9631ce8","order_by":11,"name":"Shinichi Kuriyama","email":"","orcid":"","institution":"Kyoto University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shinichi","middleName":"","lastName":"Kuriyama","suffix":""},{"id":50863788,"identity":"2e78c800-5217-42b6-ba7c-237d6a8db044","order_by":12,"name":"Mutsumi Watanabe","email":"","orcid":"","institution":"Kyoto University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Mutsumi","middleName":"","lastName":"Watanabe","suffix":""},{"id":50863789,"identity":"ee8c4d83-9ca9-4eb9-915a-ca1355b8131a","order_by":13,"name":"Tetsuya Tomita","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tetsuya","middleName":"","lastName":"Tomita","suffix":""},{"id":50863790,"identity":"be953948-4d52-4aa8-ac7a-4b6ec219751a","order_by":14,"name":"Masashi Tamaki","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Masashi","middleName":"","lastName":"Tamaki","suffix":""},{"id":50863791,"identity":"0dda568e-6ab8-42dc-99d3-bf8926fb18a9","order_by":15,"name":"Teruya Ishibashi","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Teruya","middleName":"","lastName":"Ishibashi","suffix":""},{"id":50863792,"identity":"74d804fe-2360-4ef7-b49a-b36fa12cfa53","order_by":16,"name":"Ken Okazaki","email":"","orcid":"","institution":"Tokyo Women's Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Ken","middleName":"","lastName":"Okazaki","suffix":""},{"id":50863793,"identity":"bdad104c-0aff-4edf-9440-1241562acdf0","order_by":17,"name":"Hideki Mizu-uchi","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hideki","middleName":"","lastName":"Mizu-uchi","suffix":""},{"id":50863794,"identity":"57668060-e532-4fe6-baf9-d75413ca1a02","order_by":18,"name":"Shojiro Ishibashi","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shojiro","middleName":"","lastName":"Ishibashi","suffix":""},{"id":50863795,"identity":"f4a9ab30-4a4b-46fb-a06a-0ce11e5f3c4d","order_by":19,"name":"Yuan Ma","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yuan","middleName":"","lastName":"Ma","suffix":""},{"id":50863796,"identity":"6aa907a4-37ba-4d7b-94b6-557306915e33","order_by":20,"name":"Yoichi M. Ito","email":"","orcid":"","institution":"Hokkaido University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yoichi","middleName":"M.","lastName":"Ito","suffix":""},{"id":50863797,"identity":"c09170b7-e3bd-4071-92bf-a8b1ca73c956","order_by":21,"name":"Kozo Nakamura","email":"","orcid":"","institution":"National Rehabilitation Center for Persons with Disabilities","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Kozo","middleName":"","lastName":"Nakamura","suffix":""},{"id":50863798,"identity":"e33d43f0-4287-4e54-955f-410803610989","order_by":22,"name":"Sakae Tanaka","email":"","orcid":"","institution":"University of Tokyo","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Sakae","middleName":"","lastName":"Tanaka","suffix":""}],"badges":[],"createdAt":"2021-08-23 16:14:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-841197/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-841197/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":13316606,"identity":"012b8756-10ac-4b18-8155-112937543121","added_by":"auto","created_at":"2021-09-13 14:48:55","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":65144,"visible":true,"origin":"","legend":"The average score of each item of the 25-question geriatric locomotive function scale [6] preoperatively (solid line) and postoperatively (interrupted line); pain severity rating for pain-related questionnaires (Q1-Q4): 0, none; 1, mild; 2, moderate; 3, considerable; 4, severe","description":"","filename":"KOAFigure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-841197/v1/f690bc491d6db2e7ae43bf27.jpg"},{"id":13316609,"identity":"6bd1f754-8e6f-4d78-9af9-c0bcd10cd24c","added_by":"auto","created_at":"2021-09-13 14:48:55","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":77052,"visible":true,"origin":"","legend":"Changes after total knee arthroplasty; (a-c) score distribution of the three components of the locomotive syndrome risk test pre- and postoperatively; two-step test (a), stand-up test (b), total GLFS-25 score (c); (d) EuroQol-5 Dimension was shown as the utility score","description":"","filename":"KOAFigure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-841197/v1/103df08491089541f22f6b8a.jpg"},{"id":13316607,"identity":"e84b40af-a115-4e72-a5f2-4ec2851a416f","added_by":"auto","created_at":"2021-09-13 14:48:55","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":46617,"visible":true,"origin":"","legend":"Pre- and postoperative distribution of stages in locomotive syndrome ","description":"","filename":"KOAFigure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-841197/v1/4edb2d6810f920c5981935c9.jpg"},{"id":13316608,"identity":"e4e0488c-0bd7-407b-bb8e-5180c2ddc126","added_by":"auto","created_at":"2021-09-13 14:48:55","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":75984,"visible":true,"origin":"","legend":"Changes in the locomotive syndrome risk test stratified by age (60-74 years and ≥75 years); in both the groups, similar trends were observed in the two-step test (a), stand-up test (b), and total GLFS-25 score (c), EuroQol-5 Dimension (d)","description":"","filename":"KOAFigure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-841197/v1/c5ac3dc4f5345ee72b65474d.jpg"},{"id":16857861,"identity":"e16acd20-c3f6-4507-a118-46723af31e23","added_by":"auto","created_at":"2021-12-30 06:29:14","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1151011,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-841197/v1/dd4a8f72-c8b9-424f-bcfb-503871569c18.pdf"},{"id":13316610,"identity":"b1e62d45-92a3-4534-8518-bf23aae0bced","added_by":"auto","created_at":"2021-09-13 14:48:55","extension":"pptx","order_by":9,"title":"","display":"","copyAsset":false,"role":"supplement","size":118874,"visible":true,"origin":"","legend":"","description":"","filename":"KOAFigureSup1.pptx","url":"https://assets-eu.researchsquare.com/files/rs-841197/v1/3dfbad8f0a886bf646a07a92.pptx"},{"id":13316611,"identity":"e49b4f72-c5bd-416a-9704-026bb585a264","added_by":"auto","created_at":"2021-09-13 14:48:55","extension":"docx","order_by":10,"title":"","display":"","copyAsset":false,"role":"supplement","size":13999,"visible":true,"origin":"","legend":"","description":"","filename":"locomoTKASupTable1.docx","url":"https://assets-eu.researchsquare.com/files/rs-841197/v1/ab8bf52fe49f70e8da654444.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eEfficacy of Total Knee Arthroplasty in Elderly Patients With Locomotive Syndrome: a Prospective Longitudinal Study\u003c/p\u003e","fulltext":[{"header":"Background","content":"\u003cp\u003eManaging the health problems of the aging population is now a common medical challenge in many countries including Japan where the elderly (older than 65 years) constitute more than 28% of the total population [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. In these countries, health policies are directed at prolonging the period during which the elderly can live independently without care from others. According to Japanese governmental statistics, the three leading causes of disabilities which compel the elderly to avail the services of the long-term care insurance (LTCI) system, a governmental policy to provide suitable individual care services for the disabled elderly, are cerebrovascular diseases, dementia, and musculoskeletal diseases [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Therefore, the management of problems associated with aging with respect to the musculoskeletal system is of social interest, and this prompted the Japanese Orthopaedic Association to propose the concept of the locomotive syndrome in 2007 [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Locomotive syndrome is defined as a condition of decreased mobility in activities essential to daily life such as walking, standing up, and climbing stairs, resulting from impairment of the locomotive organs [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The severity of locomotive syndrome is evaluated using the locomotive syndrome (LS) risk test, a screening tool which consists of three tests: the two-step test, stand-up test, and 25-Question Geriatric Locomotive Function Scale (GLFS-25) [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The simplicity and feasibility of these tests enable them to be used as a screening tool in various types of surveys focusing on not only the disabled elderly but also the general population [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eKnee osteoarthritis (KOA) is a common pathological condition observed in patients with locomotive syndrome [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Its painful symptoms prevent the active lifestyle typical of middle-aged people. In the later stages of the disease, the activities of daily living of the patients are also impaired [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Total knee arthroplasty (TKA) sufficiently improves both pain and knee function of KOA patients which are commonly evaluated by knee-specific patient-reported outcome measures such as the Knee Society Score and the Japanese Knee Osteoarthritis Measure [\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. As the survival rate of implants has improved, the current therapeutic challenge is to maintain long term post-operative physical activities. However, several studies have revealed that the locomotive functions gradually declined after surgery even without implant-related problems [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. This may be due to the degenerative changes in musculoskeletal organs other than knees since most Japanese people undergo initial TKA surgeries in their 70s [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Therefore, patients opting for TKA should also be evaluated using an integrated measurement tool, such as the LS risk test, for musculoskeletal function and difficulties in daily living. While the application of the test has been reported in surgical treatments for hip osteoarthritis and lumbar canal stenosis, it has not been evaluated in patients undergoing TKA surgeries [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Therefore, the purpose of this study was to evaluate the pre- and post-operative condition of patients undergoing TKA for KOA using the LS risk test to assess their condition from the point of view of integrated care in the management of musculoskeletal disorders.\u003c/p\u003e"},{"header":"Methods","content":"\u003ch2\u003eStudy participants\u003c/h2\u003e\n\u003cp\u003eFor this observational cohort study, patients who were scheduled to undergo TKA surgery were registered at six hospitals in a prospective manner. The inclusion criteria were as follows: (1) patients aged\u0026thinsp;\u0026ge;\u0026thinsp;60 and \u0026lt;\u0026thinsp;90 years and (2) those undergoing TKA for KOA in one or both knees. Those with severe comorbidities, such as chronic renal disease and chronic heart failure, were excluded. All subjects provided written informed consent prior to participation. The study was approved by the IRB of the authors\u0026rsquo; affiliated institutions and conducted in accordance with the principles of the Declaration of Helsinki.\u003c/p\u003e\n\u003ch2\u003eData collection\u003c/h2\u003e\n\u003cp\u003eThe initial data, LS risk test scores, and 5-level EuroQol-5 Dimension (EQ-5D-5L) scores together with the demographic data were collected by a medical specialist within 3 months before the surgery. The patients were instructed to visit the hospital 1 year after surgeries to undergo similar evaluations as the one stated above. For patients who underwent TKA for both knees consecutively, the follow-up evaluations were scheduled 1 year after the last surgery.\u003c/p\u003e\n\u003ch2\u003eLocomotive syndrome risk test\u003c/h2\u003e\n\u003cp\u003eThe locomotive syndrome risk test consists of one patient-reported outcome measure: the GLFS-25 and two performance tests: the two-step and stand-up tests. These tests were performed as described in previous papers [\u003cspan class=\"CitationRef\"\u003e7\u003c/span\u003e]. To summarize, the GLFS-25 included 25 questions each of which had a 0\u0026ndash;4 graded Likert scale about mobility-related difficulties in daily life, with the higher grades representing a deteriorating health condition. As for the two-step test, patients began from the standing position and then stepped forward as far as they could with the right and left steps in succession. The maximum distance covered by the two steps was divided by the patients\u0026rsquo; heights for standardization. In the stand-up test, patients were asked to sit on boxes that were 10 to 40 cm high and then stand up without any support using either one or both legs. Successful trials were recorded.\u003c/p\u003e\n\u003cdiv class=\"Section2\" id=\"Sec3\"\u003e\n \u003ch2\u003eStatistical analysis\u003c/h2\u003e\n \u003cp\u003eTo compare the demographic background between the two groups, we used Fisher\u0026rsquo;s exact test for categorical variables and the t-test for continuous variables. The differences in the pre- and post-operative test scores (LS risk test and EQ-5D) were compared using the paired t-test because of its approximately normal distribution (Supplementary Fig.\u0026nbsp;1). We used multiple imputation to handle the missing data in the GLFS-25 scores because of its relatively high percentage (22% of follow-up patients) [\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e]. We imputed by fully conditional specification method using discriminant function with Proc MI in SAS (SAS Institute, Cary, NC, USA) [\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e]. The imputation procedure used each score of all 25 questions of GLFS-25 because of their close association with the missing GLFS-25 value. The results across 20 imputed data set were combined by averaging and standard errors were adjusted according to within and between imputation variability [\u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/p\u003e\n \u003cp\u003eThe linear mixed-effects model with an unstructured covariance matrix for residuals was used to examine whether the pre- and post-operative change in each test score was different between the age groups. To control other possible confounders, we included the gender, number of TKAs (bilateral/unilateral), and body mass index in the model. We also compared the baseline test scores between patients who were followed up and those who were lost to follow-up. A p-value of less than 0.05 was considered statistically significant. All statistical analyses were performed using SAS 9.4 (SAS Institute, NC, US).\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 111 patients were enrolled in the study, 87 of whom completed the follow-up assessments. The follow-up period was 406.4\u0026thinsp;\u0026plusmn;\u0026thinsp;102.5 (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation) days after surgery. The age of the patients at the time of surgery was 74.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.9 years, ranging from 60 to 88 years. The other demographic data are presented in Table\u0026nbsp;1. The pre-operative evaluation showed that the mean scores of the two-step test, stand-up test, and GLFS-25 were 1.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25, 2.02\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14, and 38.3\u0026thinsp;\u0026plusmn;\u0026thinsp;15.8, respectively (Table\u0026nbsp;2). The details of the GLSF-25 scores are shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e, presenting the average scores for each item. The GLFS-25 questionnaire contains several items associated with \u0026ldquo;pain\u0026rdquo; (Q1: neck and upper limb pain, Q2: back and buttock pain, Q3: leg pain, and Q4: pain in motion). While the item for pain in the legs (Q3) had a higher average score than others, 48.1% of participants experienced moderate or severe pain in other parts of their bodies. Similar scores were observed in all three tests irrespective of whether the patients had undergone TKA for one or both knees. A significant difference was observed in the two-step test scores between those who dropped out and those who completed the follow-up. However, the results of the GLFS-25 and stand-up tests were similar between them (Supplementary Table\u0026nbsp;1).\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n \u003ccaption\u003e\n \u003cp\u003eTable 1\u003c/p\u003e\n \u003cp\u003eThe demographic background of the patients\u003c/p\u003e\n \u003c/caption\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003eMen (n=23)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003eWomen (n=88)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e\u0026nbsp;Total (n=111)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003eAge, mean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e74.0 \u0026plusmn; 6.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e74.7 \u0026plusmn; 5.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e74.6 \u0026plusmn; 5.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003eBMI, mean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e26.2 \u0026plusmn; 2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e26.5 \u0026plusmn; 4.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e26.4 \u0026plusmn; 3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003eBilateral operation, n(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e2 (8.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e14 (15.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e16 (14.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003eMedication\u003csup\u003e#\u003c/sup\u003e, n(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd width=\"125\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd width=\"117\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Hypertension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e14 (73.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e59 (75.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e73 (75.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Diabetes Melltius\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e2(10.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e15 (19.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e17 (17.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Nsaids\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e8(42.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e16 (20.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e24 (24.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Osteoprosis*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e19 (24.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e19 (19.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Steroid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e3 (3.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e3 (3.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"200\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Depression\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"97\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"125\"\u003e\n \u003cp\u003e4 (5.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"117\"\u003e\n \u003cp\u003e4 (4.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" width=\"540\"\u003e\n \u003cp\u003e*p\u0026lt;0.05, significant sex difference using Fisher\u0026apos;s exact test; BMI=body mass index.\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" width=\"200\"\u003e\n \u003cp\u003e#medication (n = 97).\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n \u003ccaption\u003e\n \u003cp\u003eTable 2\u003c/p\u003e\n \u003cp\u003ePre and post-operative scores of locomotive syndrome risk test and EQ-5D\u003c/p\u003e\n \u003c/caption\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"161\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"47\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" width=\"236\"\u003e\n \u003cp\u003ePre-operation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"170\"\u003e\n \u003cp\u003e1-year post operation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"142\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"95\"\u003e\n \u003cp\u003eP-value*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"161\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd width=\"47\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"104\"\u003e\n \u003cp\u003eMean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"132\"\u003e\n \u003cp\u003eMedian (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"170\"\u003e\n \u003cp\u003eMean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"142\"\u003e\n \u003cp\u003eMedian (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"95\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"161\"\u003e\n \u003cp\u003eTwo-step test score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"47\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"104\"\u003e\n \u003cp\u003e1.01 (0.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"132\"\u003e\n \u003cp\u003e1.06 (0.90-1.17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"170\"\u003e\n \u003cp\u003e1.12 (0.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"142\"\u003e\n \u003cp\u003e1.16 (1.02-1.27)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"95\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"161\"\u003e\n \u003cp\u003eStand-up test score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"47\"\u003e\n \u003cp\u003e83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"104\"\u003e\n \u003cp\u003e2.02 (1.14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"132\"\u003e\n \u003cp\u003e2 (1-3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"170\"\u003e\n \u003cp\u003e2.38 (1.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"142\"\u003e\n \u003cp\u003e2 (2-3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"95\"\u003e\n \u003cp\u003e0.0069\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"161\"\u003e\n \u003cp\u003eTotal GLFS-25 score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"47\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"104\"\u003e\n \u003cp\u003e38.3 (15.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"132\"\u003e\n \u003cp\u003e37 (26-48)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"170\"\u003e\n \u003cp\u003e18.7 (16.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"142\"\u003e\n \u003cp\u003e13 (6.5-25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"95\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"161\"\u003e\n \u003cp\u003eEQ-5D utility score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"47\"\u003e\n \u003cp\u003e83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"104\"\u003e\n \u003cp\u003e0.58 (0.14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"132\"\u003e\n \u003cp\u003e0.59 (0.53-0.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"170\"\u003e\n \u003cp\u003e0.77 (0.17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"142\"\u003e\n \u003cp\u003e0.75 (0.67-1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"95\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\" width=\"851\"\u003e\n \u003cp\u003eSD = standard deviation; IQR = interquatile range; GLFS-25 = the 25-question geriatric locomotive function scale; EQ-5D = EuroQol 5 dimensions\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\" width=\"161\"\u003e\n \u003cp\u003e* Paired t-test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe LS risk test and EQ-5D utility scores before surgery and at follow-up are shown in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e and Table 2. Significant improvements were observed in all three components of the LS risk test as well as in the EQ-5D utility scores. The improvements in the mean values were 0.11 for the two-step test, 0.36 for the stand-up test, 19.6 for the GLFS-25, and 0.19 for EQ-5D (Table 2). For the GLFS-25, the changes in each item were examined using the mean values. While most of the items showed improvement after the surgery, a marked improvement (improvement of \u0026gt;\u0026thinsp;1.5 points) was observed in Q3 (leg pain) and Q13 (difficulty in walking briskly). On the other hand, no change was observed in Q8 (difficulty in putting on and taking off shirts) (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eThe severity of locomotive syndrome is summarized by the locomotive syndrome staging criteria: normal, stage 1 (starting stage of decrease in mobility defined by two-step test score\u0026thinsp;\u0026lt;\u0026thinsp;1.3, or stand-up test score\u0026thinsp;\u0026le;\u0026thinsp;4, or GLFS-25 score\u0026thinsp;\u0026ge;\u0026thinsp;7), and stage 2 (progressing stage of decrease in mobility defined by two-step test score\u0026thinsp;\u0026lt;\u0026thinsp;1.1, or stand-up test score\u0026thinsp;\u0026le;\u0026thinsp;2, or GLFS-25 score\u0026thinsp;\u0026ge;\u0026thinsp;16) [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e]. Recently, the more severe condition of decrease in mobility was defined as stage 3 (progressed stage of decrease in mobility, restricting social engagement defined by two-step test score\u0026thinsp;\u0026lt;\u0026thinsp;0.9, or stand-up test score\u0026thinsp;\u0026le;\u0026thinsp;1, or GLFS-25 score\u0026thinsp;\u0026ge;\u0026thinsp;24) to recommend visiting medical specialists [\u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e]. In the preoperative survey, the ratio of the patients who were categorized as stage 3, 2, and 1 is 82.3%, 16.1%, and 1.6% respectively. The conversion of the stages of locomotive syndrome after surgery is presented in Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e. The ratio of stage 3 patients reduced from 82.3\u0026ndash;33.9% post-operatively, while the ratio of stage 2 patients increased from 16.1\u0026ndash;45.2%.\u003c/p\u003e\n\u003cp\u003eSince locomotive syndrome tends to progress with age, patients undergoing TKA at older ages were speculated to have a worse clinical course. While patients in the older age group showed higher GLFS-25 scores indicating a poor condition both pre- and post-operatively, there was no interaction between the age group and the pre/post-operative time period (Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). This result indicated that age (60\u0026ndash;74 years or \u0026ge;\u0026thinsp;75 years) did not affect the degree of improvement afforded by the TKA surgery. Figure \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e illustrates the parallel trend of the LS risk test between the 60\u0026ndash;74 and \u0026ge;\u0026thinsp;75 age groups.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Taba\"\u003e\n \u003ccaption\u003e\n \u003cp\u003eTable 3\u003c/p\u003e\n \u003cp\u003eThe estimated effect of age groups on the change of pre-and post operative test scores, using linear mixed effects model\u003c/p\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003cth align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eOutcomes and fixed effects\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eEstimate\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eSE\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003edf\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003et value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePr \u0026gt;|t|\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u003cspan class=\"BoldItalic\"\u003eTwo-step test score\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod (post operation)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.028\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e4.430\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eSex (male)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.177\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.048\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e3.670\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eAge group (age\u0026thinsp;\u0026ge;\u0026thinsp;75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.087\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.052\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.680\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.098\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eNumber of TKA (bilateral)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.013\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.051\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.260\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.792\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eBMI (bmi\u0026thinsp;\u0026ge;\u0026thinsp;25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.059\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.041\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.430\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.156\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod \u0026times; age group\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.029\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.041\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.710\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.480\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u003cspan class=\"BoldItalic\"\u003eStand-up test score\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod (post operation)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.198\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.195\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e1.010\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.313\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eSex (male)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.615\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.257\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e2.400\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.019\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eAge group (age\u0026thinsp;\u0026ge;\u0026thinsp;75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.401\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.251\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.600\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.113\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eNumber of TKA (bilateral)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.402\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.268\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.138\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eBMI (bmi\u0026thinsp;\u0026ge;\u0026thinsp;25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.399\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.220\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.820\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.073\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod \u0026times; age group\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.371\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.286\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e1.300\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.199\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u003cspan class=\"BoldItalic\"\u003eTotal GLFS-25 score\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod (post operation)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-18.612\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e2.444\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-7.620\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eSex (male)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-9.172\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e3.668\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-2.500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.015\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eAge group (age\u0026thinsp;\u0026ge;\u0026thinsp;75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e9.152\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e3.500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e2.620\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eNumber of TKA (bilateral)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-5.003\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e3.893\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.290\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.203\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eBMI (bmi\u0026thinsp;\u0026ge;\u0026thinsp;25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e3.729\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e3.170\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e1.180\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.243\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod \u0026times; age group\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.688\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e3.536\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.480\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.635\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u003cspan class=\"BoldItalic\"\u003eEQ-5D utility score\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod (post operation)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.208\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.028\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e7.320\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eSex (male)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.066\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e2.010\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.047\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eAge group (age\u0026thinsp;\u0026ge;\u0026thinsp;75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.045\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.410\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.161\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eNumber of TKA (bilateral)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.018\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.510\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.600\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003eBMI (bmi\u0026thinsp;\u0026ge;\u0026thinsp;25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.028\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-1.230\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.224\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 35px;\"\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003ePeriod \u0026times; age group\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.025\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.042\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e-0.590\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"height: 35px;\"\u003e\n \u003cp\u003e0.557\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 48px;\"\u003e\n \u003ctd align=\"left\" colspan=\"6\" style=\"height: 48px;\"\u003e\n \u003cp\u003eOutcomes are three locomotive syndrome risk test scores and EQ-5D utility score. Each estimate reflects an association between each outcome (test score) and independent variables, adjusting for all other variables in the model.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr style=\"height: 59px;\"\u003e\n \u003ctd align=\"left\" colspan=\"6\" style=\"height: 59px;\"\u003e\n \u003cp\u003eReference\u0026thinsp;=\u0026thinsp;period (pre-operation), female (sex), age\u0026thinsp;\u0026lt;\u0026thinsp;75(age group), unilateral TKA (number of TKA), BMI (bmi\u0026thinsp;\u0026lt;\u0026thinsp;25)\u003c/p\u003e\n \u003cp\u003eSE\u0026thinsp;=\u0026thinsp;standard error; GLFS-25\u0026thinsp;=\u0026thinsp;the 25-question geriatric locomotive function scale; EQ-5D\u0026thinsp;=\u0026thinsp;EuroQol 5 dimensions; BMI\u0026thinsp;=\u0026thinsp;body mass index.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn total, 16 participants (14.4%) underwent bilateral knee operation during the survey period. The magnitude of improvement was not affected by the number of TKAs (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, we described the condition of the musculoskeletal organs in patients undergoing TKA by the LS risk test and evaluated the changes afforded by the surgery. Our data clearly showed that most of the patients belonged to locomotive syndrome stage 2 or 3 pre-operatively (98.4%), and TKA improved their condition in terms of patient-oriented outcome measures and objective function tests.\u003c/p\u003e \u003cp\u003eA recent report on the reference values of the LS risk test in a healthy population showed that the median GLFS-25 scores for those aged between 65 and 69, and 75 and 79 were 4 and 6, respectively [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. On the other hand, Yamada et al. reported that the mean GLFS-25 score for the elderly who availed the services of the LTCI system was 33.8 [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In our study, the average preoperative GLFS-25 score was 38.3 suggesting that the pre-operative condition of patients undergoing TKA was similar to the condition of individuals who need care and support and have a risk of dependency. The significant improvement in the GLFS-25 and other tests after TKA confirmed that joint replacement surgeries have a beneficial impact not only on knee pain and function but also on the improvement of general musculoskeletal function.\u003c/p\u003e \u003cp\u003eThe selection of the optimal age is critical for successful surgeries [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Our study showed that the degree of improvement provided by TKA is equivalent between the older (\u0026ge;\u0026thinsp;75 years) and younger (64\u0026ndash;74 years) age groups, suggesting that surgery is expected to improve the ability to perform daily activities even in older patients. However, it should be noted that the pre- and post-operative GLFS-25 scores were higher in the older age group than that of the younger age group (mean post-operative GLFS-25 score, \u0026ge;\u0026thinsp;75 age group, 21.8\u0026thinsp;\u0026plusmn;\u0026thinsp;19.4 vs. 60\u0026ndash;74 age group, 16.0\u0026thinsp;\u0026plusmn;\u0026thinsp;13.5). As the number of people using the LTCI services increases after the age of 75, the residual dysfunction and difficulty in daily activities among the older age group patients should be carefully monitored so that their physical condition can be maintained through suitable lifestyle modifications and if necessary, treatments.\u003c/p\u003e \u003cp\u003eOne of the advantages of the LS risk test is its ability to evaluate the condition of the musculoskeletal organs in an integrated manner. In our study, 48.1% of patients had moderate or severe pain in sites other than the leg, suggesting that the patients suffered not only from KOA but also from other musculoskeletal disorders such as degenerative spinal disorders and upper limb pain. As previously reported, many patients tend to have multiple bone and joint diseases, and the difficulties faced by them in daily life reflect the summation of all these symptoms [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Using the LS risk test, the physician can gauge the overall impact of the disease on patients\u0026rsquo; daily living and the function of their locomotive organs. The integrated difficulties in the daily living of patients with multiple musculoskeletal problems have been evaluated using various quality of life assessment scales such as EQ-5D, a well-established scale that consists of five questionnaires, assessing the mobility, self-care, activity, pain, and anxiety [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Because Seichi et al. reported that the GLFS-25 score correlated well with the EQ-5D score, the GLFS-25 has a potential to be used as a quality of life outcome measure for patients with musculoskeletal diseases as demonstrated in the current study where the two scales showed similar trends [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. While the LS risk test questionnaire form takes longer to complete which is a disadvantage, its wide range of scores provides sufficient sensitivity to detect changes during longitudinal observation. Therefore, the LS risk test would be useful for a long-term follow-up analysis in patients undergoing conservative treatment and/or musculoskeletal surgeries in organs other than the knee joints. In future, the data accumulated from the LS risk test during the long-term follow-up will help physicians develop therapeutic strategies for managing the mobility function of each patient.\u003c/p\u003e \u003cp\u003eOur study has several limitations. First, we excluded patients with severe comorbidities from the study. Therefore, the current data should be considered as information conceived from typical clinical cases of KOA. In cases with severe comorbidities, the score of the LS risk test would be influenced by conditions other than those affecting the bones and joints and would need to be interpreted more cautiously. Second, since the minimum clinically important difference (MCID) of the LS risk test has not been established, the efficacy of treatment in each case cannot be determined. Further studies are required to determine the MCID to identify the factors that may have an impact on the efficacy of treatment. Finally, a fraction of patients was lost to follow-up. The lower score observed in the two-step test in the lost to follow-up group suggests the possibility that patients who had poor mobility after surgery could not turn up for the follow-ups. As this is an inherent limitation in longitudinal studies related to mobility disorders, an alternative method of data collection from patients who have restricted mobility is required in future studies.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn conclusion, we observed that the LS risk test was useful in evaluating patients undergoing TKA. In the baseline assessment, the scores revealed that the physical condition of the patients was similar to that of individuals who required assistance for their daily activities. These tests can also be used to describe changes after surgery, providing qualitative information about difficulties in daily life and functions. The locomotive syndrome risk test is a feasible tool for evaluating patients with musculoskeletal diseases of varying severity and with multiple symptoms.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eLTCI: long-term care insurance\u003c/p\u003e\n\u003cp\u003eLS: locomotive syndrome\u003c/p\u003e\n\u003cp\u003eGLFS-25: 25-Question Geriatric Locomotive Function Scale\u003c/p\u003e\n\u003cp\u003eKOA: knee osteoarthritis\u003c/p\u003e\n\u003cp\u003eTKA: total knee arthroplasty\u003c/p\u003e\n\u003cp\u003eEQ-5D-5L: 5-level EuroQol-5 Dimension\u003c/p\u003e\n\u003cp\u003eMCID: minimum clinically important difference\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate: All subjects provided written informed consent prior to participation, which was approved by the ethical committee of the University of Tokyo (No. 11256) as well as by each hospital.\u003c/p\u003e\n\u003cp\u003eConsent for publication: Not applicable\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials: The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003eCompeting interests: All authors declare that they have no conflicts of interest.\u003c/p\u003e\n\u003cp\u003eFunding: This study was supported by JOA-Subsidized Science Project Research 2015-1. The funder had no role in collection, analyses, and interpretation of the data, nor decision to submit results.\u003c/p\u003e\n\u003cp\u003eAuthors\u0026apos; contributions: TO, KN and ST designed the study. KY and YI performed statistical analyses. HM and KO established data collecting systems. KH, TK, KW, TK, YI, YY, TS, SM, SK, MW, TT, MT, TI, HM, SI and YM collected data and interpreted the patient data. TO and KY wrote the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003eAcknowledgements: Not applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003e\u003cstrong\u003eUnited Nations. World Population Ageing 2017 Highlights\u0026nbsp;\u003c/strong\u003e[\u003ca href=\"https://www.un.org/en/development/desa/population/publications/pdf/ageing/WPA2017_Highlights.pdf\"\u003ehttps://www.un.org/en/development/desa/population/publications/pdf/ageing/WPA2017_Highlights.pdf\u003c/a\u003e]\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eCabinet Office, Government of Japan. Annual Report on the Ageing Society. 2019\u0026nbsp;\u003c/strong\u003e[\u003ca href=\"https://www8.cao.go.jp/kourei/whitepaper/w-2019/gaiyou/pdf/1s1s.pdf\"\u003ehttps://www8.cao.go.jp/kourei/whitepaper/w-2019/gaiyou/pdf/1s1s.pdf\u003c/a\u003e]\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eMinistry of Health, Labour and Welfare. Long-Term Care Insurance System of Japan\u0026nbsp;\u003c/strong\u003e[\u003ca href=\"http://www.mhlw.go.jp/english/policy/care-welfare/care-welfare-elderly/dl/ltcisj_e.pdf\"\u003ehttp://www.mhlw.go.jp/english/policy/care-welfare/care-welfare-elderly/dl/ltcisj_e.pdf\u003c/a\u003e]\u003c/li\u003e\n \u003cli\u003eNakamura K: \u003cstrong\u003eA \u0026quot;super-aged\u0026quot; society and the \u0026quot;locomotive syndrome\u0026quot;\u003c/strong\u003e. \u003cem\u003eJ Orthop Sci\u0026nbsp;\u003c/em\u003e2008, \u003cstrong\u003e13\u003c/strong\u003e(1):1-2.\u003c/li\u003e\n \u003cli\u003eNakamura K, Ogata T: \u003cstrong\u003eLocomotive Syndrome: Definition and Management\u003c/strong\u003e. \u003cem\u003eClin Rev Bone Miner Metab\u0026nbsp;\u003c/em\u003e2016, \u003cstrong\u003e14\u003c/strong\u003e:56-67.\u003c/li\u003e\n \u003cli\u003eSeichi A, Hoshino Y, Doi T, Akai M, Tobimatsu Y, Iwaya T: \u003cstrong\u003eDevelopment of a screening tool for risk of locomotive syndrome in the elderly: the 25-question Geriatric Locomotive Function Scale\u003c/strong\u003e. \u003cem\u003eJ Orthop Sci\u0026nbsp;\u003c/em\u003e2012, \u003cstrong\u003e17\u003c/strong\u003e(2):163-172.\u003c/li\u003e\n \u003cli\u003eOgata T, Muranaga S, Ishibashi H, Ohe T, Izumida R, Yoshimura N, Iwaya T, Nakamura K: \u003cstrong\u003eDevelopment of a screening program to assess motor function in the adult population: a cross-sectional observational study\u003c/strong\u003e. \u003cem\u003eJ Orthop Sci\u0026nbsp;\u003c/em\u003e2015, \u003cstrong\u003e20\u003c/strong\u003e(5):888-895.\u003c/li\u003e\n \u003cli\u003eYoshimura N, Muraki S, Oka H, Tanaka S, Ogata T, Kawaguchi H, Akune T, Nakamura K: \u003cstrong\u003eAssociation between new indices in the locomotive syndrome risk test and decline in mobility: third survey of the ROAD study\u003c/strong\u003e. \u003cem\u003eJ Orthop Sci\u0026nbsp;\u003c/em\u003e2015, \u003cstrong\u003e20\u003c/strong\u003e(5):896-905.\u003c/li\u003e\n 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The locomotive syndrome staging criteria (Japanese)\u0026nbsp;\u003c/strong\u003e[\u003ca href=\"https://locomo-joa.jp/assets/pdf/locomo-testjudge.pdf\"\u003ehttps://locomo-joa.jp/assets/pdf/locomo-testjudge.pdf\u003c/a\u003e]\u003c/li\u003e\n \u003cli\u003eKondo K, Tanaka T, Hirota Y, Kawamura H, Miura H, Sugioka Y, Inoue H, Kurosaka M, Yamashita T, Shirata K\u003cem\u003e\u0026nbsp;et al\u003c/em\u003e: \u003cstrong\u003eFactors associated with functional limitation in stair climbing in female Japanese patients with knee osteoarthritis\u003c/strong\u003e. \u003cem\u003eJ Epidemiol\u0026nbsp;\u003c/em\u003e2006, \u003cstrong\u003e16\u003c/strong\u003e(1):21-29.\u003c/li\u003e\n \u003cli\u003eChang CB, Yoo JH, Koh IJ, Kang YG, Seong SC, Kim TK: \u003cstrong\u003eKey factors in determining surgical timing of total knee arthroplasty in osteoarthritic patients: age, radiographic severity, and symptomatic severity\u003c/strong\u003e. \u003cem\u003eJ Orthop Traumatol\u0026nbsp;\u003c/em\u003e2010, \u003cstrong\u003e11\u003c/strong\u003e(1):21-27.\u003c/li\u003e\n \u003cli\u003eImagama S, Ando K, Kobayashi K, Seki T, Hamada T, Machino M, Ota K, Tanaka S, Morozumi M, Kanbara S\u003cem\u003e\u0026nbsp;et al\u003c/em\u003e: \u003cstrong\u003eImpact of comorbidity rates of lumbar spondylosis, knee osteoarthritis, and osteoporosis on physical QOL and risk factors for poor physical QOL in middle-aged and elderly people\u003c/strong\u003e. \u003cem\u003eMod Rheumatol\u0026nbsp;\u003c/em\u003e2020, \u003cstrong\u003e30\u003c/strong\u003e(2):402-409.\u003c/li\u003e\n \u003cli\u003eRat AC, Guillemin F, Osnowycz G, Delagoutte JP, Cuny C, Mainard D, Baumann C: \u003cstrong\u003eTotal hip or knee replacement for osteoarthritis: mid- and long-term quality of life\u003c/strong\u003e. \u003cem\u003eArthritis Care Res (Hoboken)\u0026nbsp;\u003c/em\u003e2010, \u003cstrong\u003e62\u003c/strong\u003e(1):54-62.\u003c/li\u003e\n \u003cli\u003eConner-Spady BL, Marshall DA, Bohm E, Dunbar MJ, Loucks L, Al Khudairy A, Noseworthy TW: \u003cstrong\u003eReliability and validity of the EQ-5D-5L compared to the EQ-5D-3L in patients with osteoarthritis referred for hip and knee replacement\u003c/strong\u003e. \u003cem\u003eQual Life Res\u0026nbsp;\u003c/em\u003e2015, \u003cstrong\u003e24\u003c/strong\u003e(7):1775-1784.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"total knee arthroplasty, locomotive syndrome, elderly patients, longitudinal study, health problems","lastPublishedDoi":"10.21203/rs.3.rs-841197/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-841197/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground: To preserve the ability to perform physical activities among the elderly, the concept of locomotive syndrome and its evaluation method, the locomotive syndrome risk test, have been applied in an integrated manner to capture the decline in mobility resulting from musculoskeletal disorders. During treatment, physicians can use the locomotive syndrome risk test to evaluate the impact of each therapy such as total knee arthroplasty for knee osteoarthritis, a common disorder found in locomotive syndrome. The purpose of this study was to evaluate the impact of total knee arthroplasty in the elderly with respect to locomotive syndrome.\u003c/p\u003e\u003cp\u003eMethods: A total of 111 patients were registered at six hospitals prior to total knee arthroplasty and postoperatively followed up for 1 year. Three components of the locomotive syndrome risk test (the two-step test, stand-up test, and geriatric locomotive function scale-25) were assessed together with the EuroQol-5 Dimension scores pre- and postoperatively.\u003c/p\u003e\u003cp\u003eResults: Post surgery, all three components of the locomotive syndrome risk test as well as the EuroQol-5 Dimension utility score showed significant improvements from the baseline (two-step test, 1.01±0.25 to 1.12±0.21; stand-up test, 2.02±1.14 to 2.38±1.20; geriatric locomotive function scale-25, 38.3±15.8 to 18.7±16.6, mean ± standard deviation). The ratio of stage 3 locomotive syndrome patients (progressed stage of decrease in mobility, restricting social engagement) reduced from 82.3% to 33.9% postoperatively. There was no significant difference in the degree of change in the three test scores between the younger (60-74 years) and older (≥75 years) age groups. \u003c/p\u003e\u003cp\u003eConclusions: We found that total knee arthroplasty has a major impact in preventing the progression of locomotive syndrome in patients with knee osteoarthritis. The locomotive syndrome risk test is a feasible tool for longitudinal evaluation of patients with musculoskeletal diseases of varying severity and with multiple symptoms.\u003c/p\u003e\u003cp\u003eTrial registration: This study was registered as UMIN000023595 (10/08/2016)\u003c/p\u003e","manuscriptTitle":"Efficacy of Total Knee Arthroplasty in Elderly Patients With Locomotive Syndrome: a Prospective Longitudinal Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2021-09-13 14:48:53","doi":"10.21203/rs.3.rs-841197/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0d213d1c-1766-4693-8552-53bf882505ed","owner":[],"postedDate":"September 13th, 2021","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":7147108,"name":"Geriatrics \u0026 Gerontology"}],"tags":[],"updatedAt":"2021-12-30T06:29:05+00:00","versionOfRecord":[],"versionCreatedAt":"2021-09-13 14:48:53","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-841197","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-841197","identity":"rs-841197","version":["v1"]},"buildId":"FbvkV6FR0MCFSLy54lSbu","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}