Iran Journal of Nursing

Introduction
Knee osteoarthritis (KO) is the most common joint disease in the elderly and the main cause of chronic pain and disability in both developed and developing countries. Various factors such as obesity, physical inactivity and joint injury play a role in its occurrence. This disease is associated with pain, and reduced range of motion, as well as complete cartilage destruction and disability. Due to the pain and limitation of knee movement and muscle weakness, older people have difficulty performing daily activities. The pain is aggravated by activities such as climbing stairs and walking. The onset of knee pain is usually gradual and worsens with prolonged activity, frequent use of stairs, and inactivity. Impairment in performing the activities of daily living can lead to consequences such as fatigue, reduced social functioning, reduced quality of life, and sleep problems. Pharmacological and non-pharmacological methods are used for KO treatment which mainly focus on reducing pain and improving physical function and quality of life. Patients with mild intermittent symptoms need non-pharmacological treatment, and while those with stable and debilitating pain need non-pharmacological treatment and exercise is the best intervention for them. 
Non-pharmacological approaches play an important role in managing symptoms and preventing disability in KO. One of the main components of KO treatment is strengthening the function and strength of joint muscles, because muscle weakness makes the joint more prone to injury. Exercise, as a non-pharmacological method, can restore the physiological function of synoviocytes, prevent the occurrence of osteoarthritis and postpone the need for joint replacement. The results of a meta-analysis in 2021 suggested that exercise is a safe and effective method for patients with KO, and can mainly reduce their pain. Physical activity and exercise have few side effects and can reduce the intensity of pain and improve physical function and quality of life of patients and lead to improvement of their physical and mental health. Exercise programs by strengthening the hip and leg joints reduce pain in patients with KO. The effects of pain relief with exercise therapy not only are greater than non-steroidal anti-inflammatory drugs and acetaminophen, but also has no side effects. 
Various studies have been conducted on different methods of exercises for patients with KO, but none of them have mentioned a specific protocol; their results have reported low to high effects of exercises on pain. Considering the different results of studies about the effects of exercise in reducing the pain of KO patients and the lack of studies on older adults in this field in Iran, this study aims to determine the effect of a regular home workout program on the pain of older patients with KO.
Materials and Methods
In this randomized controlled clinical trial conducted in March 2021 for three months, 70 older people with KO were selected using a convenience sampling method and randomly assigned to exercise and control groups. The patients in the exercise group were first trained by the researcher for 4 weeks in the clinic of Allameh Bohlool Gonabadi Hospital as a trial at 4 sessions of 30 minutes ( from 10 a.m. to 12 p.m.). For another 4 weeks, the patients performed exercises at home twice a day for one month. The control group received routine treatment program and had no any contact with the patients in the exercise group. The program included exercises to strengthen the quadriceps, calf muscles, hamstrings, gluteus maximus, internal thigh and abdominal muscles. A demographic/clinical profile form and knee injury and osteoarthritis outcome score (KOOS) were used to collect data. The Persian version of KOOS was validated by Salvati who reported a Cronbach’s alpha of 0.88. Data were analyzed in SPSS software, version 18 using descriptive and inferential statistics. The significance level was set at 0.05.
Results 
Based on the results of chi-square test, Fisher’s exact test and independent t test, there was no significant difference between the two groups in terms of age, height, weight, body mass index, duration of illness, gender, marital status, educational level, economic status, occupation, using/not using stairs, history of frequent heavy load carrying, history of sitting cross-legged, history of joint injury, family history of illness and the two groups were homogenous. According to the results of independent t-test, there was no statistically significant difference between the two groups before the intervention (P=0.587), but the difference was significant after the intervention (P=0.009). With an effect size of 0.74, it can be said that the home workout program had a moderate effect on the pain of patients.
Discussion
 The home workout program has a positive effect on pain reduction and can lead to better pain control. It is recommended to use this program as a simple and cost-effective intervention for the rehabilitation of patients with KO along with other treatment methods. It is recommended to compare the effectiveness of home workout program in two age groups of elderly and non-elderly. The home workout program is also recommended for the elderly with osteoarthritis in other joints.

Ethical Considerations
Compliance with ethical guidelines
This study was approved by the Research Ethics Committee of Shahed University (IR.SHAHED.REC.1399.145) and registered by Iranian Registry of Clinical Trials (ID: IRCT20210129050172N1)

Funding
The study was extracted from the master thesis of the first author approved by Shahed University, Tehran, Iran. 

Authors' contributions
Investigation: Sara Safarnia Shahri; Supervision and project administration: Mohammad Reza Heidari; Data analysis: Anooshirvan Kazemnejad; Preparing initial draft, editing & review: Mohammad Reza Heidari, Sara Safarnia Shahri, Meisam Moradi.

Conflict of interest
The authors declared no conflict of interest.

Acknowledgments
The authors would like to thank to the Deputy for Research of Shahed University and all the patients for their cooperation in this research.

References

1. Zhang M, Theleman JL, Lygrisse KA, Wang J. Epigenetic mechanisms underlying the aging of articular cartilage and osteoarthritis. Gerontology. 2019; 65(4):387-96.[DOI:10.1159/000496688] [PMID] [PMCID]
2. Flynn DM. Chronic musculoskeletal pain: Nonpharmacologic, noninvasive treatments. Am Fam Physician. 2020; 102(8):465-77. [PMID]
3. Hawker GA. Osteoarthritis is a serious disease. Clin Exp Rheumatol. 2019; 37 Suppl 120(5):3-6. [PMID]
4. Törmälehto S, Mononen ME, Aarnio E, Arokoski JPA, Korhonen RK, Martikainen J. Health-related quality of life in relation to symptomatic and radiographic definitions of knee osteoarthritis: Data from Osteoarthritis Initiative (OAI) 4-year follow-up study. Health Qual Life Outcomes. 2018; 16(1):154.[DOI:10.1186/s12955-018-0979-7] [PMID] [PMCID]
5. Millerand M, Berenbaum F, Jacques C. Danger signals and inflammaging in osteoarthritis. Clin Exp Rheumatol. 2019; 37 Suppl 120(5):48-56. [PMID]
6. Park JS, Yoon T, Lee SH, Hwang NK, Lee JH, Jung YJ, et al. Immediate effects of kinesiology tape on the pain and gait function in older adults with knee osteoarthritis. Medicine. 2019; 98(45):e17880. [DOI:10.1097/MD.0000000000017880] [PMID] [PMCID]
7. Sharma L. Osteoarthritis of the Knee. N Engl J Med. 2021; 384(1):51-9. [DOI:10.1056/NEJMcp1903768] [PMID]
8. Tavares DRB, Okazaki JEF, Rocha AP, Santana MVA, Pinto ACPN, Civile VT, et al. Effects of transcranial direct current stimulation on knee osteoarthritis pain in elderly subjects with defective endogenous pain-inhibitory systems: Protocol for a randomized controlled trial. JMIR Res Protoc. 2018; 7(10):e11660. [DOI:10.2196/11660] [PMID] [PMCID]
9. Askari A, Shahabfard Z, Ehrampoush E, Bahramali E, Homayounfar R. [Metabolic syndrome as a risk factor for osteoarthritis (Persian)]. J Fasa Univ Med Sci. 2015; 5(1):1-13. [Link]
10. Rahmati M, Nalesso G, Mobasheri A, Mozafari M. Aging and osteoarthritis: Central role of the extracellular matrix. Ageing Res Rev. 2017; 40:20-30. [DOI:10.1016/j.arr.2017.07.004] [PMID]
11. Zarei P, Rahnama N. [Comparison of the effects of the two strengthening and balanced, strengthening, balanced, and core-stability exercise protocols on the balance and fear of falling in women with knee osteoarthritis (Persian)]. J Paramed Sci Rehabil. 2018; 7(2):43-54. [DOI:10.22038/JPSR.2018.19866.1496]
12. Schuring N, Aoki H, Gray J, Kerkhoffs GMMJ, Lambert M, Gouttebarge V. Osteoarthritis is associated with symptoms of common mental disorders among former elite athletes. Knee Surg Sports Traumatol Arthrosc. 2017; 25(10):3179-85.  [DOI:10.1007/s00167-016-4255-2] [PMID] [PMCID]
13. Vaughn IA, Terry EL, Bartley EJ, Schaefer N, Fillingim RB. Racial-ethnic differences in osteoarthritis Pain and disability: A meta-analysis. J Pain. 2019; 20(6):629-44. [DOI:10.1016/j.jpain.2018.11.012] [PMID] [PMCID]
14. Mills K, Hübscher M, O'Leary H, Moloney N. Current concepts in joint pain in knee osteoarthritis. Schmerz. 2019; 33(1):22-9. [DOI:10.1007/s00482-018-0275-9] [PMID]
15. Dainese P, Wyngaert KV, De Mits S, Wittoek R, Van Ginckel A, Calders P. Association between knee inflammation and knee pain in patients with knee osteoarthritis: A systematic review. Osteoarthritis Cartilage. 2022; 30(4):516-34.[DOI:10.1016/j.joca.2021.12.003] [PMID]
16. Chen CJ, McHugh G, Campbell M, Luker K. Subjective and objective sleep quality in individuals with osteoarthritis in Taiwan. Musculoskeletal Care. 2014; 13(3):148-59. [DOI:10.1002/msc.1094] [PMID]
17. Clynes MA, Jameson KA, Edwards MH, Cooper C, Dennison EM. Impact of osteoarthritis on activities of daily living: Does joint site matter? Aging Clin Exp Res. 2019; 31(8):1049-56. [DOI:10.1007/s40520-019-01163-0] [PMID] [PMCID]
18. Brown A. Holistic/integrative interventions relieve knee osteoarthritis pain in older adults. J Nurs Pract. 2020; 16(1):57-9. [DOI:10.1016/j.nurpra.2019.10.018]
19. Ferreira RM, Torres RT, Duarte JA, Gonçalves RS. Non-pharmacological and non-surgical interventions for knee osteoarthritis: A systematic review and meta-analysis. Acta Reumatol Port. 2019; 44(3):173-217. [PMID]
20. Davis AM, MacKay C. Osteoarthritis year in review: Outcome of rehabilitation. Osteoarthritis Cartilage. 2013; 21(10):1414-24. [DOI:10.1016/j.joca.2013.08.013] [PMID]
21. Ahanjan S, Shafipour A, Mehrabian H, Shojaedin SS. [Comparison of knee osteoarthritis in retired professional zurkhaneh athletes and non-athletic individuals (Persian)]. J Kerman univ med sci. 2015; 22(1):53-60. [Link]
22. Di Rosa M, Castrogiovanni P, Musumeci G. The synovium theory: Can exercise prevent knee osteoarthritis? The role of "mechanokines", a possible biological key. J Funct Morphol Kinesiol. 2019; 4(1):11. [DOI:10.3390/jfmk4010011] [PMID] [PMCID]
23. Raposo F, Ramos M, Lúcia Cruz A. Effects of exercise on knee osteoarthritis: A systematic review. Musculoskeletal Care. 2021; 19(4):399-435. [DOI:10.1002/msc.1538] [PMID]
24. Geneen LJ, Moore RA, Clarke C, Martin D, Colvin LA, Smith BH. Physical activity and exercise for chronic pain in adults: An overview of Cochrane Reviews. Cochrane Database Systematic Reviews. Hoboken, New Jersey: John wiley & sons; 2017.  [DOI:10.1002/14651858.CD011279.pub2]
25. Lun V, Marsh A, Bray R, Lindsay D, Wiley P. Efficacy of hip strengthening exercises compared with leg strengthening exercises on knee pain, function, and quality of life in patients with knee osteoarthritis. Clin J Sport Med. 2015; 25(6):509-17. [DOI:10.1097/JSM.0000000000000170] [PMID]
26. Skou ST, Pedersen BK, Abbott JH, Patterson B, Barton C. Physical activity and exercise therapy benefit more than just symptoms and impairments in people with hip and knee osteoarthritis. J Orthop Sports Phys Ther. 2018; 48(6):439-47. [DOI:10.2519/jospt.2018.7877] [PMID]
27. Kabiri S, Halabchi F, Angoorani H, Yekaninejad S. Comparison of three modes of aerobic exercise combined with resistance training on the pain and function of patients with knee osteoarthritis: A randomized controlled trial. Phys Ther Sport. 2018; 32:22-8. [DOI:10.1016/j.ptsp.2018.04.001] [PMID]
28. Altaş EU, Demirdal Ü. The effect of physical therapy and rehabilitation modalities on sleep quality in patients with primary knee osteoarthritis: A single-blind, prospective, randomized-controlled study. Turk J Phys Med Rehabil. 2020; 66(1):73-83. [DOI:10.5606/tftrd.2020.3089] [PMID] [PMCID]
29. Kars Fertelli T, Mollaoglu M, Sahin O. Aquatic exercise program for individuals with osteoarthritis: Pain, stiffness, physical function, self-efficacy. Rehabil Nurs. 2019; 44(5):290-9. [DOI:10.1097/rnj.0000000000000142] [PMID]
30. Henriksen M, Klokker L, Graven-Nielsen T, Bartholdy C, Schjødt Jørgensen T, Bandak E, et al. Association of exercise therapy and reduction of pain sensitivity in patients with knee osteoarthritis: A randomized controlled trial. Arthritis Care Res. 2014; 66(12):1836-43. [DOI:10.1002/acr.22375] [PMID]
31. Munukka M, Waller B, Häkkinen A, Nieminen MT, Lammentausta E, Kujala UM, et al. Effects of progressive aquatic resistance training on symptoms and quality of life in women with knee osteoarthritis: A secondary analysis. Scand J Med Sci Sports. 2020; 30(6):1064-72. [DOI:10.1111/sms.13630] [PMID]
32. Roos EM, Lohmander LS. The Knee injury and osteoarthritis outcome score (KOOS): From joint injury to osteoarthritis. Health Qual Life Outcomes. 2003; 1:64. [DOI:10.1186/1477-7525-1-64] [PMID] [PMCID]
33. Salavati M, Mazaheri M, Negahban H, Sohani SM, Ebrahimian MR, Ebrahimi I, et al. Validation of a persian-version of knee injury and osteoarthritis outcome score (KOOS) in Iranians with knee injuries. Osteoarthritis Cartilage. 2008; 16(10):1178-82.[DOI:10.1016/j.joca.2008.03.004] [PMID]
34. Abdollahi A, Goodarzi B, Shakoori SK. [The effect of isokinetic training on pain and function in patients with knee osteoarthritis: clinical trial (Persian)]. Med J Tabriz Univ Med Sci. 2019; 41(1):56-64. [DOI:10.34172/mj.2019.007]
35. Bagheri S, Shojaedin S, Naderi A, Hosseini SH, Nikoo MR. [Comparing two therapeutic methods of hip abductor-quadriceps strengthening and quadriceps strengthening alone on pain and function in women with knee osteoarthritis (Persian)]. Anesthesiol Pain. 2016; 6(4):46-55. [Link]
36. Nejati P, Farzinmehr A, Moradi-Lakeh M. The effect of exercise therapy on knee osteoarthritis: a randomized clinical trial. Med J Islam Repub Iran. 2015; 29:186. [PMID] [PMCID]
37. Yuenyongviwat V, Duangmanee S, Iamthanaporn K, Tuntarattanapong P, Hongnaparak T. Effect of hip abductor strengthening exercises in knee osteoarthritis: A randomized controlled trial. BMC Musculoskelet Disord. 2020; 21(1):284.[DOI:10.1186/s12891-020-03316-z] [PMID] [PMCID]
38. Rewald S, Lenssen AFT, Emans PJ, de Bie RA, van Breukelen G, Mesters I. Aquatic cycling improves knee pain and physical functioning in patients with knee osteoarthritis: A randomized controlled trial. Arch Phys Med Rehabil. 2020; 101(8):1288-95. [DOI:10.1016/j.apmr.2019.12.023] [PMID]
39. Taglietti M, Facci LM, Trelha CS, de Melo FC, da Silva DW, Sawczuk G, et al. Effectiveness of aquatic exercises compared to patient-education on health status in individuals with knee osteoarthritis: a randomized controlled trial. Clinical Rehabilitation. 2018; 32(6):766-76. [DOI:10.1177/0269215517754240] [PMID]
40. Thorstensson CA, Roos EM, Petersson IF, Ekdahl C. Six-week high-intensity exercise program for middle-aged patients with knee osteoarthritis: A randomized controlled trial [ISRCTN20244858]. BMC Musculoskelet Disord. 2005; 6:27. [DOI:10.1186/1471-2474-6-27] [PMID] [PMCID]
41. Messier SP, Mihalko SL, Beavers DP, Nicklas BJ, DeVita P, Carr JJ, et al. Effect of high-intensity strength training on knee pain and knee joint compressive forces among adults with knee osteoarthritis: The start randomized clinical trial. JAMA. 2021; 325(7):646-57. [DOI:10.1001/jama.2021.0411] [PMID] [PMCID]
42. Susko AM, Fitzgerald GK. The pain-relieving qualities of exercise in knee osteoarthritis. Open Access Rheumatol. 2013; 5:81-91. [DOI:10.2147/OARRR.S53974] [PMID] [PMCID]
43. Runhaar J, Bierma-Zeinstra SMA. Should exercise therapy for chronic musculoskeletal conditions focus on the anti-inflammatory effects of exercise? Br J Sports Med. 2017; 51(10):762-3. [DOI:10.1136/bjsports-2016-096489] [PMID]
44. Juhl C, Christensen R, Roos EM, Zhang W, Lund H. Impact of exercise type and dose on pain and disability in knee osteoarthritis: A systematic review and meta-regression analysis of randomized controlled trials. Arthritis Rheumatol. 2014; 66(3):622-36 [DOI:10.1002/art.38290] [PMID]
45. Bartholdy C, Juhl C, Christensen R, Lund H, Zhang W, Henriksen M. The role of muscle strengthening in exercise therapy for knee osteoarthritis: A systematic review and meta-regression analysis of randomized trials. Semin Arthritis Rheum. 2017; 47(1):9-21. [DOI:10.1016/j.semarthrit.2017.03.007] [PMID]
46. Dantas LO, Salvini TF, McAlindon TE. Knee osteoarthritis: key treatments and implications for physical therapy. Braz J Phys Ther. 2021; 25(2):135-46.[DOI:10.1016/j.bjpt.2020.08.004] [PMID] [PMCID]