- Journal List
- Acta Ortop Bras
- v.20(3); 2012
- PMC3718434
As a library, NLM provides access to scientific literature. Inclusion in an NLM database does not imply endorsem*nt of, or agreement with, the contents by NLM or the National Institutes of Health.
Learn more: PMC Disclaimer | PMC Copyright Notice
Acta Ortop Bras. 2012; 20(3): 174–179.
PMCID: PMC3718434
PMID: 24453599
Aline Mizusaki Imoto, Maria Stella Peccin, and Virgínia Fernandes Moça Trevisani
Author information Article notes Copyright and License information PMC Disclaimer
Abstract
Objective
The purpose of this research was to verify the effectiveness of an eight-weekquadriceps strengthening program on pain, function and quality of life of patients withknee osteoarthritis.
Methods
A hundred patients were randomized into two groups: 1- Exercise Group (ExG) and 2-Orientation Group. The Timed Up and Go (TUG) test, the Numerical Rating Scale (NRS) andthe Short Form-36 were used for the assessment.
Results
Eighty-one patients completed the survey. According to the intention to treat (ITT)analysis, there was statistically significant difference in ExG compared to OG in allthe variables assessed.
Conclusion
The program quadriceps strengthening exercises applied in this randomized clinicaltrial was effective in improving pain, function and quality of life of patients withknee osteoarthritis. Level of Evidence I, Randomized ClinicalTrial.
Keywords: Knee, Exercise therapy, Osteoarthritis/rehabilitation,
INTRODUCTION
Osteoarthritis (OA) is a chronic disease, located in the joints, affecting one third ofadults and presenting a tendency to increase with age.1 Knee OA can be associated with symptoms of pain, instability, reductionof range of motion (ROM) and consequently, deterioration in quality of life and function.This functional limitation results in an increase of the risk of morbidity andmortality.2,3
Authors report that patients with knee OA present less quadriceps muscle strength incomparison to the control group. As the quadriceps muscle plays the role of shock absorber,a weakness of this muscle decreases the joint protection, resulting in greater stress andoverload on the knee.4 Quadricepsstrengthening exercises performed over eight weeks proved just as effective in functionimprovement as the use of non-hormonal anti-inflammatory drugs in patients with OA of theknee.5 Moreover, moderate-intensityexercises showed themselves to be a good form of treatment not only for the improvement ofsymptoms, but also in the increase of the glycosaminoglycan content.6
Fransen and McConnell7 carried out asystematic review of the effectiveness of exercises in patients with knee OA. The authorsverified that these have a beneficial effect on pain and function. However, there wasaccentuated variability in terms of the type of exercise evaluated and particularly inrelation to the methodological aspects. Besides the physical benefits, the exercises alsohad a beneficial effect on the mental health of patients with knee OA. Thus, due to the factthat reduced mobility is one of the main factors responsible for limitation of functionalityand deterioration of quality of life in patients with knee OA, it is extremely important toconduct research on interventions based on an appropriate methodology, targeting theimprovement of the functionality and quality of life of these patients.4 The objective of this randomized clinical trialwas to verify the effect of an open kinetic chain quadriceps strengthening exercise programon the pain, function and qualify of patients with knee OA.
METHODS
The rheumatologists of the Department of Rheumatology of the Ambulatório deEspecialidades de Interlagos (Specialty Outpatient Clinic) referred the patients included inthe present study. A statistician performed the allocation of the patients using a computerprogram. Aiming to avoid selection bias, a third person numbered and sealed the opaqueenvelopes.
All the patients signed a consent term upon joining the group for participation in thestudy. The patients involved in the survey are registered with the Department ofRheumatology of the Ambulatório de Especialidades de Interlagos - São Paulo,Brazil. The study was conducted over the period between April 2007 and April 2009.
Approval by the Ethics Committee
The Institutional Reasearch Board of Universidade Federal de São Paulo approvedthis study under the following registration number: CEP 0141/07.
Sample Size
It was estimated that a sample of 40 patients would be able to detect a minimum clinicaldifference of 1minute ± 3 seconds in the Timed Up and Go (TUG) test, with the powerof 80%.8-10 We employed a paired comparison between the three groups withsignificance level of 0.05 (Student's T-test), using a covariance analysis (ANCOVA). Thepresent study followed the gold standard of evidence in rheumatology, allocating 50patients in each group.10
Participant
One hundred patients were selected according to the inclusion and exclusion criteriaestablished previously. The patients were allocated in two groups:
1) Exercise Group (ExG) (n = 50)
2) Orientation Group (OG) (n = 50).
The inclusion criteria were: age between 50 and 75 years, diagnosis of knee OA accordingto the criteria of the American College of Rheumatology (ACR) based on history, physicalexamination and radiographic findings (pain in the knee and one of the following items -over 50 years of age, less than 30min of morning stiffness and crepitation in activemovement and osteophytes), knee x-ray in the last 12 months and grade 2 or above in theKellgren and Lawrence radiographic classification. Patients with a diagnosis offibromyalgia, unstable heart condition, physical activity more often than twice a week,inability to pedal a stationary bicycle and previous knee arthroplasty were not included.The occurrence of adverse events was considered an exclusion criterion.
Medication
The patients' medications were standardized and remained the same during the interventionperiod. Paracetamol was the drug prescribed for analgesia while diacerein and chloroquinediphosphate were used for control of OA.
Orientation Group (OG)
Patient orientation can be defined as "any educational activity planned with theobjective of improving the patient's state of health".11 The patients from the Orientation group received anexplanation about the manual after the initial evaluation. The orientation manual (Figure 1) consisted of a description of knee OA, as wellas the possible signs and symptoms presented by the patients, and pointed them in thedirection of a better way of dealing with the functional difficulties.
Figure 1
Manual for patients with knee osteoarthritis. Caption: ExG- Exercise Group OG –Orientation Group.
Over a period of eight weeks, the patients received two phone calls as a means ofencouragement to follow the orientations.
Exercise Group (ExG)
The patients from the ExG group took part in group sessions lasting from 30 to 40minutes, with a weekly frequency of twice a week.
The load used for muscle strengthening was based on the 10 maximum repetitionstest.12 After estimating 100% of theload, 50-60% of this load was established for use in the strengthening of the patientsfrom the study.
The exercise protocol used by us consisted of 10 minutes of warm-up on a stationarybicycle, ischiotibial stretching exercises and three series of 15 repetitions of kneeextension exercises, aiming to strengthen the quadriceps muscle. The interval betweenseries was from 30 to 45 seconds. The load used in the exercise was increased according totolerance. The patient's positioning for the exercise was: seated in a chair, with 90degrees of knee and hip flexion. The patients from the ExG also received the orientationmanual given to the OG group. (Figure 1)
ASSESSMENT
The pre and post-intervention assessments were carried out by a physiotherapist blinded tothe patient's group. The following items were evaluated:
Functional performance by means of the TUG test: TUG is a low cost test with a simplemethod that was developed to assess the patient's functional mobility in everydayactivities. This test involves the following sequence of movements: getting out of thechair, walking three meters, turning around and sitting down on the chair again. The timethat the patient takes to perform the movement sequence is recorded for comparison beforeand after treatment.8 In our study, thepatients had a chance to become familiar with the test before the collection time wasrecorded. The best time recorded from three attempts was used. The level of pain was measured using the Numerical Rating Scale from 0 to 10.13 (Figure2)
Figure 2
Flowchart of the patients over the course of the study.
Quality of life - we used the SF-36 questionnaire,14 which contains 36 items that assess functional capacity, physicalaspects, pain, general state of health, vitality, social aspects, emotional aspects andmental health. The scoring of each item of the questionnaire ranges from 0 to 100, wherezero corresponds to the worst general state of health and 100 to the best state ofhealth.14
Statistical Analysis
The paired t-test was used for the assessment between the pre and post-interventiontimes. Alpha=5% was used in all the tests, and tests with p<0.05 were consideredstatistically significant. For the intention to treat (ITT) analysis, which includes allthe patients who were randomized, we used mixed model variance analysis (ANOVA) withrepeated measurements, with measurements of occasion as intragroup factor and interventionas intergroup factor. The relations between observations were analyzed as an unstructuredcovariance matrix. There was no data input in the ITT to evaluate the pre and postdifferences between the three groups evaluated, since Chakraborty and Gu15 showed that the mixed model of analysis,without data input, always provides power greater than or equal to the analyses that usethe mixed model, with lost data input. In both analyses, the effect size was computed asthe difference between the means, divided by the standard deviation, using Cohen's d. TheKruskal-Wallis statistical test was used for comparison between the groups, in relation tothe number of days on which analgesic consumption was necessary.
RESULTS
The patients' demographic characteristics in terms of sex, side treated, age, body massindex (BMI), grade of OA according to Kellgren and Lawrence and the values of the initialassessment of NRS, TUG and of the aspects of SF 36 (functional capacity, physical aspects,pain, general state of health, vitality, social aspects, emotional aspects and mentalhealth) are described in Table 1. We can observe thehom*ogeneity of the groups in relation to the demographic characteristics evaluated.
Table 1
Demographic characteristics of the patients and baseline value means.
| Variable | OG | ExG | p-value |
| Sex+ | |||
| Woman | 94.00 | 90.00 | 0.76 |
| Man | 6.00 | 10.00 | |
| Side treated + | |||
| Right | 34.00 | 22.00 | 0.35 |
| Left | 41.67 | 25.00 | |
| Bilateral | 22.92 | 29.17 | |
| Age* | 58.78 ±9.60 | 61.50 ±6.94 | 0.23 |
| BMI* | 30.00 ±5.05 | 29.72 ±4.11 | 0.95 |
| KL Grade+ | 0.83 | ||
| 2 | 91.18 | 92.68 | |
| 3 | 5.88 | 4.88 | |
| 4 | 2.94 | 2.44 | |
| Pain (NRS)* | 6.92 ±2.60 | 7.42 ±2.01 | 0.49 |
| Timed up and go test* | 10.08 ±2.96 | 9.34 ±2.47 | 0.40 |
| SF-36* | |||
| Functional Capacity | 34.53 ±24.76 | 31.00 ±19.59 | 0.66 |
| Physical Aspects | 25.60 ±38.39 | 27.16 ±38.74 | 0.98 |
| Pain | 34.51 ±24.30 | 34.47 ±18.27 | 0.83 |
| General State | 50.77 ±21.43 | 52.24 ±27.72 | 0.23 |
| Vitality | 52.53 ±22.08 | 53.11 ±23.04 | 0.40 |
| Social Aspects | 63.56 ±29.27 | 71.24 ±26.01 | 0.42 |
| Emotional Aspects | 35.49 ±42.06 | 47.22 ±46.69 | 0.46 |
| Mental Health | 55.88 ±24.15 | 59.27 ±24.86 | 0.08 |
Open in a separate window
Caption: OG - Orientation Group; ExG - Exercise Group; BMI - Body Mass Index; NRS -Numerical Rating Scale; SF-36 - Short Form-36 TUG - Timed Up and Go Test; CI -Confidence Interval;.* - Values presented as mean (SD); + - Values presented aspercentage.
Eighty-one patients (n = 43 in ExG and n = 38 in OG) finished the study. In the ExG group,one patient was excluded due to failure to attend the sessions, while two were instructed tostay at home for a week due to inflammation in the knee. However, the inflammatory statepersisted, which made them unable to continue with the exercises of the protocol.Consequently, they did not terminate the protocol and were excluded from the study. Onepatient had a death in the family (spouse) and declared herself psychologically and sociallyincapable of continuing with the treatment, two began in a new job and one started treatmentnearer his home. In OG, one patient fractured his ankle and 11 did not return for the finalassessment even after being contacted by phone. (Figure2)
Tug test and NRS
ExG presented statistically significant reduction of pain intensity (NRS)(p<0.0001) and in the timing of the TUG test (p<0.0001). (Table 2) OG did not present statistically significantchanges in the reduction of the pain level (NRS) or in the TUG test (p>0.05).(Table 2) As regards the comparison betweengroups, considering the intention to treat analysis, there was statistically significantdifference in ExG when compared to OG in the NRS (p=0.00) and TUG (p=0.00) outcome. (Table 3)
Table 2
Results between the pre and post-intervention times.
| Variable | Groups | Pre | Post | Mean difference (CI of 95%) | p-value |
| Pain (NRS) | OG | 6.92 ±2.60 | 5.743.14 | -0.88 (-1.92;0.15) | 0.09 |
| ExG | 7.43 ±2.01 | 4.272.45 | -3.17 (-4.23;-2.10) | <.0001* | |
| TUG | OG | 10.08 ±2.96 | 9.223.31 | -0.57(-1.20;0.06) | 0.07 |
| ExG | 9.34±2.47 | 7.421.70 | -2.00(-2.54;-1.46) | <.0001* | |
| SF-36 | |||||
| Functional Capacity | OG | 34.53 ±24.76) | 41.5526.66 | 6.96(-0.46;14.39) | 0.06 |
| ExG | 31 ±19.59) | 49.3823.94 | 20.28(12.68; 27.88) | <.0001* | |
| Physical Aspects | OG | 25.6±38.39 | 39.6647.49 | 13.39(-4.59;31.38) | 0.13 |
| ExG | 27.16±38.74 | 53.1346.41 | 27.85(9.13;46.57) | 0.00* | |
| Pain | OG | 34.51±24.3 | 4424.94 | 6.14 (-5.27;17.55) | 0.27 |
| ExG | 34.47±18.27 | 46.9825.3 | 16.40 (6.18;26.61) | 0.00* | |
| General State of Health | OG | 50.77±21.43 | 59.3122.28 | 5.89 (-1.34;13.13) | 0.10 |
| ExG | 52.24±27.72 | 61.6825.54 | 8.05 (1.21;14.89) | 0.02* | |
| Vitality | OG | 52.53±22.08 | 56.7223 | 3.17 (-8.08;14.44) | 0.56 |
| ExG | 53.11±23.04 | 6321.95 | 10 (2.26;17.73) | 0.012* | |
| Social Aspects | OG | 63.56±29.27 | 67.7632.27 | 0.35(-13.97; 14.69) | 0.95 |
| ExG | 71.24±26.01 | 80.7324.29 | 9.57(-0.76;19.9) | 0.06 | |
| Emotional Aspects | OG | 35.49±42.07 | 48.3148.47 | 13.21 (-10.75;37.18) | 0.26 |
| ExG | 47.22±46.7 | 64.1846.78 | 16.22(-2.68;35.14) | 0.09 | |
| Mental Health | OG | 55.88±24.15 | 60.4120.9 | 1.28(-7.86;10.43) | 0.77 |
| ExG | 59.27±24.86 | 64.324.35 | 3.77(-4.31;11.85) | 0.35 | |
Open in a separate window
Caption: OG - Orientation Group; ExG - Exercise Group; NRS - Numerical RatingScale; CI -Confidence Interval; *Statistically significant result, p≤0.05.
Table 3
Comparison between groups.
| Variable | Comparison between groups | Difference between the means - CI (95%) | Effect size CI (95 %) | p-value |
| Pain (NRS) | OG x ExG | 2.09 (0.71 ; 3.46) | 0.72 (0.24 ; 1.18) | 0.00* |
| TUG | OG x ExG | 1.29 (0.54 ; 2.04) | 0.81 (0.33 ; 1.28) | 0.00* |
| SF-36 | ||||
| Functional Capacity | OG x ExG | -12.39 (-23.44; -1.33) | 0.72 (0.24; 1.18) | 0.02* |
| Physical Aspects | OG x ExG | -12.16 (-36.69; 12.37) | -0.23 (-0.68; 0.23) | 0.32 |
| Pain | OG x ExG | -4.71 (-21.49; 12.05) | -0.16 (-0.61; 0.30) | 0.49 |
| General State of Health | OG x ExG | -1.66 (-11.46; 8.14) | -0.08 (-0.53; 0.38) | 0.73 |
| Vitality | OG x ExG | -6.03 (-17.29; 5.22) | -0.24 (-0.70; 0.21) | 0.29 |
| Social Aspects | OG x ExG | -6.52 (-21.09; 8.05) | -0.20 (-0.59; 0.31) | 0.37 |
| Emotional Aspects | OG x ExG | -3.55 (-30.44; 23.35) | -0.07 (-0.52; 0.39) | 0.79 |
| Mental Health | OG x ExG | -1.46 (-12.09; 9.17) | -0.06 (-0.52; 0.39) | 0.78 |
Open in a separate window
Caption: OG - Orientation Group; ExG - Exercise Group; NRS - Numerical RatingScale; TUG - Timed Up and Go Test; CI - Confidence Interval; * The comparisonpresented statistically significant difference, p< 0.05.
SF-36 Questionnaire
In ExG, the evaluation of the items of the SF-36 quality of life questionnaire showedstatistically significant improvement in the aspects functional capacity (p<0.001),pain (p=0.00), physical aspects (p=0.00), general state of health (p=0.02) and vitality(p=0.01). (Table 2) There was no statisticallysignificant change in the scores of emotional aspects, mental health and social aspects.(Table 2) The assessments of the patients fromOG did not show statistically significant pre and post-intervention difference in theevaluation of the aspects of the SF-36 quality of life questionnaire. In the intergroupcomparison, only the functional capacity aspect presented statistically significantdifference in ExG when compared to OG (p=0.02). (Table3)
DISCUSSION
The present study showed the effectiveness of an exercise protocol for quadricepsstrengthening through the evaluation of pain, TUG test and quality of life. It is worthemphasizing that Outcome Measures in Rheumatology recommends the measurement of pain andfunction as a prerequisite for the assessment of patients with knee, hand and hipOA.16
The rehabilitation protocol applied by us lasted for 8 weeks, in twice-weekly sessions. Thequality of life aspects that presented a statistically significant improvement were:functional capacity, physical aspects, pain, vitality and general state of health. Our studyis consistent with Aglamis et al.17 whoobserved a statistically significant pre and post- intervention improvement in the exercisegroup in the following aspects of SF-36: functional capacity, pain and general state ofhealth.
In the study by Foley et al.,18 the onlystatistical significant improvement brought about by the strengthening exercises was in themental aspect of the SF-12 questionnaire, with no statistically significant difference inthe score related to physical aspects. The main difference between the study by Foley etal.18 and the present study was theshorter duration of the intervention, which consisted of six weeks. However, both studiesperformed a rehabilitation protocol that involved 12 or more sessions. According to Fransenand McConnell,7 exercise programs thatinclude more than 12 sessions are associated with an improvement in relation to pain andfunction.
The focus of the orientation program used in this survey was to advise the patients on howto adjust their daily activities to decrease overload on the knee. The patients wereprovided with verbal and written guidance, based on the orientation manual distributed tothe patients from both groups, which consisted of a brief description of knee OA, as well asthe signs, symptoms and possible functional limitations. Moreover, the manual instructed thepatients to apply a hot water bottle with the temperature ranging from warm to hot in caseof pain with absence of signs of inflammation and use of an ice pack to improve pain whenaccompanied by swelling. It is worth emphasizing that such guidelines were reinforced duringthe sessions. The main goal of an orientation program is to maintain or improve health or,in some cases, to decrease the deterioration of the clinical state. However, the orientationgroup did not present statistically significant improvement in any of the aspects of SF-36or in the evaluation of pain by means of the numerical rating scale. Nunez et al.19 observed a statistically significantimprovement in a group that received guidance in the aspects pain and functional capacity ofthe SF-36 questionnaire. The main difference between the orientation program of this studyand that used by Nunes is the fact that we did not include the exercise instruction as thiswas not the objective of the present survey. Thomas et al.20 verified that the patients who received only telephone callsas a means of contact intended as guidance and to monitor the symptoms of the patients withknee OA did not present statistically significant reduction in the pain level. On the otherhand, the patients who performed exercises at home presented significant decrease in pain,suggesting that the effect of rehabilitation of patients with knee OA is not due to thepsychosocial effects but rather to the performance of exercises.
The systematic review carried out by Fransen and McConnel7 on exercises for knee OA verified that only 56% of the studiesincluded performed blind evaluation, 43% used ITT analysis and only 43% executed a blindadequate allocation. The present study considered the methodological aspects to allow theperformance of a clinical study of good quality and low risk of bias. To describe thisclinical trial, the authors followed the Consort Statement (Consolidated Standards ofReporting Trials), which targets the improvement of quality of ECR articles21.
CONCLUSION
Quadriceps strengthening exercises included in a rehabilitation program are effective inthe improvement of pain, function and quality of life aspects of patients with kneeosteoarthritis.
Footnotes
All the authors declare that there is no potential conflict of interest referring to thisarticle.
Study conducted in the Department of Internal and Therapeutic Medicine of theUniversidade Federal de São Paulo (Unifesp).
REFERENCES
1. Felson DT. Developments in the clinical understanding ofosteoarthritis. Arthritis Res Ther. 2009;11(1):203. [PMC free article] [PubMed] [Google Scholar]
2. Maurer BT, Stern AG, Kinossian B, Cook KD, Schumacher HR Jr. Osteoarthritis of the knee: isokinetic quadriceps exercise versus aneducational intervention. Arch Phys Med Rehabil. 1999;80(10):1293–9. [PubMed] [Google Scholar]
3. Fidelix TS, Soares BG, Trevisani VF. Diacerein for osteoarthritis. Cochrane Database Syst Rev. 2006;(1):CD005117. [PubMed] [Google Scholar]
4. Hurley MV. The role of muscle weakness in the pathogenesis ofosteoarthritis. Rheum Dis Clin North Am. 1999;25(2):283–98. [PubMed] [Google Scholar]
5. Doi T, Akai M, Fujino K, Iwaya T, Kurosawa H, Hayashi K, et al. Effect of home exercise of quadriceps on knee osteoarthritis compared withnonsteroidal antiinflammatory drugs: a randomized controlled trial. Am J Phys Med Rehabil. 2008;87(4):258–69. [PubMed] [Google Scholar]
6. Roos EM, Dahlberg L. Positive effects of moderate exercise on glycosaminoglycan content in kneecartilage: a four-month, randomized, controlled trial in patients at risk ofosteoarthritis. Arthritis Rheum. 2005;52(11):3507–14. [PubMed] [Google Scholar]
7. Fransen M, McConnell S. Exercise for osteoarthritis of the knee. Cochrane Database Syst Rev. 2008;(4):CD004376. 18843657. [PubMed] [Google Scholar]
8. Podsiadlo D, Richardson S. The timed "Up & Go": a test of basic functional mobility for frailelderly persons. J Am Geriatr Soc. 1991;39(2):142–8. [PubMed] [Google Scholar]
9. Troosters T, Gosselink R, Decramer M. Six-minute walk test: a valuable test, when properlystandardized. Phys Ther. 2002;82(8):826–7. [PubMed] [Google Scholar]
10. Tugwell P, Shea B, Boers M, Brooks P, Simon Lea.Evidence-based Rheumatology Disponível em: http://www.blackwellpublishing.com/medicine/bmj/rheumatology/pdfs/intro.pdf [Google Scholar]
11. Lorig KR, Mazonson PD, Holman HR. Evidence suggesting that health education for self-management in patientswith chronic arthritis has sustained health benefits while reducing health carecosts. Arthritis Rheum. 1993;36(4):439–46. [PubMed] [Google Scholar]
12. Felício J. Efeito do treinamento aeróbio associado ao treinamentoresistido nas variáveis hemodinâmicas, flexibilidade e força emindivíduos hipertensos [monografia] Bauru: Universidade Estadual Paulista; 2008. [Google Scholar]
13. Farrar JT, Young JP Jr, LaMoreaux L, Werth JL, Poole RM. Clinical importance of changes in chronic pain intensity measured on an11-point numerical pain rating scale. Pain. 2001;94(2):149–58. [PubMed] [Google Scholar]
14. Ciconelli RM, Ferraz MB, Santos W, Meinão I, Quaresma MR. Tradução para a língua portuguesa evalidação do questionário genérico deavaliação de qualidade de vida SF-36 (Brasil SF-36) Rev Bras Reumatol. 1999;39(3):143–50. [Google Scholar]
15. Chakraborty H, Gu H.2009A Mixed Model Approach for Intent-to-Treat Analysis in Longitudinal ClinicalTrials with Missing Values. RTI Presspublication; No. MR-0009-0903. Research Triangle Park,NC: RTI International; Retrieved[date]. Dsponível em: http://www.rti.org/rtipress [Google Scholar]
16. Bellamy N, Kirwan J, Boers M, Brooks P, Strand V, Tugwell P, et al. Recommendations for a core set of outcome measures for future phase IIIclinical trials in knee, hip, and hand osteoarthritis. Consensus development at OMERACTIII. J Rheumatol. 1997;24(4):799–802. [PubMed] [Google Scholar]
17. AglamiŞ B, Toraman NF, Yaman H. Change of quality of life due to exercise training in knee osteoarthritis:SF-36 and WOMAC. J Back Musculoskelet Rehabil. 2009;22(1):43-5, 47-8, 46. [PubMed] [Google Scholar]
18. Foley A, Halbert J, Hewitt T, Crotty M. Does hydrotherapy improve strength and physical function in patients withosteoarthritis--a randomised controlled trial comparing a gym based and a hydrotherapybased strengthening programme. Ann Rheum Dis. 2003;62(12):1162–7. [PMC free article] [PubMed] [Google Scholar]
19. Nuñez M, Nuñez E, Segur JM, Macule F, Quinto L, Hernandez MV, et al. The effect of an educational program to improve health-related quality oflife in patients with osteoarthritis on waiting list for total knee replacement: arandomized study. Osteoarthritis Cartilage. 2006;14(3):279–85. [PubMed] [Google Scholar]
20. Thomas KS, Muir KR, Doherty M, Jones AC, O'Reilly SC, Bassey EJ. Home based exercise programme for knee pain and knee osteoarthritis:randomised controlled trial. BMJ. 2002;325(7367):752. [PMC free article] [PubMed] [Google Scholar]
21. Moher D, Hopewell S, Schulz KF, Montori V, Gøtzsche PC, Devereaux PJ, et al. CONSORT 2010 Explanation and Elaboration: Updated guidelines for reportingparallel group randomised trials. J Clin Epidemiol. 2010;63(8):e1–37. [PubMed] [Google Scholar]
Articles from Acta Ortopedica Brasileira are provided here courtesy of Department of Orthopedics and Traumatology, Faculdade de Medicina da Universidade de São Paulo
