Received: February 04, 2020; Accepted: February 17, 2020; Published: February 20, 2020.
Background: Osteoarthritis (OA) is a common disease especially among elderly, and it has major public health burden and consequences. Despite being a common illness, there is a dearth of studies that examined prevalence and socio-demographic correlations of knee OA in the Arab region, especially in the Gulf area.
Objective: The aim of the present study is threefold. First, to describe the socio-demographic and clinical profiles of patients suffering from OA in Oman. Second, to evaluate the indicators of physical quality of life among patients with OA. Third, to compare patients’ gender in terms of selected clinical characteristics and indicators of physical quality of life.
Methods: A cross-sectional study was conducted among patients diagnosed with OA attending a secondary care referral polyclinic in Muscat. The study was conducted from January to December 2013. Socio-demographic variables were collected through a structured questionnaire. The researchers used the standardized and validated Arabic version of Knee Injury and Osteoarthritis Outcome Score- Physical Function Short Form(KOOS-PS) questionnaire to assess the physical disability of patients with knee osteoarthritis.
Results: The study included 213 participants. Of them,171 (80.3%) were females and 42 (19.7%) were males. The female participants were older in age, less educated, with lower income, and were more overweight compared to their male counterparts. About one third of participants reported OA in other joints beside the knee, especially elbow and wrist. The majority had OA for less than a year. About 12% reported a prior history of physical trauma. The majority (63%) reported other chronic illnesses. (33%) of those, had at least one complication from those illnesses. About 22% reported using herbal medicine, and 4.2% reported using oil preparations. Participants reported a wide range of indices of physical quality of life. Overall, severe indices were more common among females compared to males. The majority (75%) reported having pain getting out of bed. This pain was described as severe by 24% of participants, and it was more reported among females compared to males (22% vs. 12%, P-value 0.02). About 46% reported severe pain while bending. However, this pain was more common among males compared to females (55% vs. 44%, P-value 0.05). About 19% reported severe pain while kneeling, and it was significantly different among females compared to males (22% vs. 5%, P-value 0.02). A similar pattern was also reported with severe pain while sitting with legs crossed.
Conclusions: The study provides suggestive evidence for increased severity of physical quality of life among patients suffering from OA in Oman. The severity of physical quality of life was more prominent among females compared to males.
The Oman’shealth care system has been lauded for addressing most of the healthcare needsthrough a wide geographical distribution of primary, secondary and tertiary care. As a first line of contact with the community, the primary health care system has played a major role in the delivery of good-quality health services. At this level, there are several preventive and curative services provided to various types of health conditions, including chronic conditions leading to disabilities like osteoarthritis (OA).
There is increasing recognition that disease affecting weight-bearing joints like the knee joint, has greater harmful impact in health-related quality of life. About 80% of patients with OA have some degree of movement limitation. Around 25% cannot perform major activities of daily living (ADL's), 11% of adults with knee OA need help with personal care and 14% require help with their routine needs. About 40% of adults with knee OA reported their health as "poor" or "fair." . Moreover, OA of the knee joint is the leading cause of physical disability in both developed and developing countries [2,3]. In the United States, about 42.4% (21.1 million) of adults with doctor-diagnosed arthritis report limitations in their usual activities due to their arthritis and around 31% of working age adults with doctor-diagnosed arthritis report being limited in work due to arthritis . If such data is present in a very well developed country like the United States, then the situation might be worse in developing countries.
OA is a frequently slowly progressive joint disease typically seen in middle-aged to elderly people. The disease occurs when the joint cartilage breaks down often because of mechanical stress or biochemical alterations, causing the bone underneath to fail . OA can occur together with other types of arthritis, such as gout or rheumatoid arthritis. It is the most common form of arthritis and this condition is sometimes referred to as arthrosis or degenerative joint disease. OA tends to affect commonly used joints such as the hands and spine, and the weight-bearing joints such as the hips and knees.
It can be diagnosed clinically (elderly with knee pain, stiffness less than 30 minutes, crepitus, bony enlargement &/or tenderness, no warmth), or in combination with radiological findings of osteocytes, or laboratory blood work ( normal Rheumatic Factor and Estimated Sedimentation Rate) to rule out other causes of arthritis .There are many different pathological and radiological changes characterizing this disease [6,7].When a joint develops osteoarthritis, the cartilage covering the ends of the bones gradually roughens and becomes thin. This happens over the main surface of the knee joint or in the cartilage underneath the patella. The bone beneath the cartilage reacts by growing thicker. All the tissues within the joint are more active than normal, as if the body is trying to repair the damage.
The prevalence of osteoarthritis varies worldwide but still presents a public health concern. This disease is common among elderly and it starts to become apparent only after age 40. Hence, as the population ages, we expect an increase in its prevalence. In the United States of America, overall OA affects 13.9% of adults aged 25 and older and 33.6% (12.4 million) of those 65 and older: an estimated 26.9 million US adults in 2005 up from 21 million in 1990 (8,9). It affects 10% of Canada’s population . In the Kingdom of Saudi Arabia, one study found around 13% cases of clinical OA of the knee among adults and the prevalence of OA increased with increasing age reaching 30.8% in those aged 46-55 years and 60.6% in the age group 66-75 years .
Recently in the summer of 2010 in Bahrain, a public health audit was done by students of public health programs exploring osteoarthritis in their community. This audit showed that osteoarthritis of major joints alone was 74%, of generalized was 21% and of small joints of hands and feet alone was 5%. Within major osteoarthritis, 48% were knees alone and 51% were knee and hip . Oman is similar in culture to Bahrain and Saudi Arabia, so we are expecting similar huge burden of the knee OA. Unfortunately, there is no information regarding the prevalence in Oman till now. However, a house-to-house population survey of 920 adults done in Oman early 1990’s, showed that about 15% of females and 18% of males reported knee pain . The way Omanis sit during their social gatherings: usually on the floor with knees fully flexed, might contribute to the degeneration process of the knee joint.
This chronic, non-communicable, debilitating disease needs to be explored by further studies in the Omani community. This paper will concentrate on the OA of the knee joint. This is because the knee is the largest joint in the body, and also one of the most complicated ones. It is the weight bearing joint and needs to be strong enough to take the body weight and must lock into position to allow standing. However, it also has to act as a hinge to enable walking and must withstand extreme stresses, twists and turns to allow full range of movements during sports, exercises or even extreme physical sitting positions.
As many other chronic non-communicable health conditions, OA is a multifactorial disease. There are many factors, both modifiable and non-modifiable, that can increase the risk of this illness, and it is often a combination of these factors that leads to its development.
The non-modifiable risk factors for developing knee osteoarthritis include:
Age: Osteoarthritis usually starts from the late 40s onwards. This is probably due to factors like weakening of the muscles and the body being less able to heal itself.
Gender: it is more common in women than in men. It’s most common in women over the age of 50 years, although there’s no strong evidence that it is directly linked to the menopause. It is often associated with mild arthritis of the joints at the ends of the fingers (nodal OA), which is also more common in women . The risks of osteopenia and osteoporosis, which are increasing in menopause, have a role of increase incidence of OA.
Genetic factors: Genetic factors play a part in osteoarthritis of the knee in different ways. It may affect collagen, one of the important components of cartilage, or the way the bone reacts and repairs itself, or even the inflammatory process [15-18].
The modifiable risk factors of OA knees are important because we need to target those in order to improve the symptoms and quality of life for patients with this condition, and these include:
Obesity: body mass index (BMI) is a very important factor in causing osteoarthritis generally, but especially in the knee as it is the weight bearing joint. It also increases the chances that osteoarthritis becoming progressively worse [19,20].
Joint injury/ structural mal-alignment: very hard, repetitive activity or physically demanding jobs can increase the risk of osteoarthritis [21- 23]. Here we can include the extreme flexion of the knee joints during sitting in the Omani population.
Other types of joint disease – Sometimes osteoarthritis is a result of damage from a different kind of joint disease, such as rheumatoid arthritis, that occurred years before.
Estrogen deficiency: This hypothesis came from the fact that OA is most common in women after menopause. There are progressive structural and functional changes on articular structures that commence at early menopause and persist post-menopause. Both experimental and observational evidence support a relevant role for levels of estrogen in the homeostasis of joint tissues, and hence, in the health status of joints. Indeed, levels of estrogen influence their metabolism at many crucial stages and through several complex molecular mechanisms [24,25].
There is a lack of studies in Oman in this aspect despite it being a very common debilitating condition. OA research and clinical trials will lead to a better understanding of the disease and its risk factors, which will aid in developing better treatment options at the primary care level. The aims of this this study is to:
1) Describe the socio-demographic and anthropometric characteristics in Omani patients with knee OA.
2) Describe the clinical characteristics in Omani patients with knee OA, especially in relation to use of herbal medication.
3) Describe the indicators of physical quality of life among patients with OA.
This paper will not explore all of the above-mentioned modifiable and non-modifiable factors. Instead, this descriptive study will highlight the correlation of OA knees with age, gender, and obesity as we are trying to describe its pattern in Oman. However, the rest of the risk factors still play an important role in its management. Although it is known that there is currently no cure for this disease, the focus of the primary health care providers should be to maximize the patients’ movements and keep them as active as possible in order to improve their quality of life.
This is a cross-sectional descriptive study carried out in two secondary healthcare centers in Willay at Bowsher in Muscat Governorate, the Capital of Oman. The study was conducted during the period from January to December 2013.
The two healthcare centers were Bowsher Polyclinic and Diwan Health Complex. Both centers provide a full package of secondary healthcare services and have specialized clinics that cover Orthopedics, Sport Medicine, in addition to other Internal Medicine and surgical services. The participants in the study were selected by convenient sampling among patients diagnosed with arthritis and aged 35 years or more, who visited one of the two health centers during the study period.
The sample size has been estimated using the EPI Info version 6.0 computer program. With a type-1 error of 5% (alpha = 0.05) and 95% level of significance, it was estimated that 240 participants will be required in order for the study to detect a 50% difference in odds ratio (OR) at a power level of 90%. Therefore, the target has been set for 240 participants in order to achieve the objective of the study.
Data was collected through an interview conducted by a qualified staff nurse who is well trained to fill in the administered questionnaire. A total of 240 participants were approached, and 224 (93.0%) consented to participate in the study. Nonetheless, 11 questionnaires were excluded from the study due to incomplete responses. Therefore, a total of 213 participants were included in the analysis.
Adaption of the Screening Measures:
The questionnaire was composed of two sections. The first section solicited socio-demographic and clinical indicators as shown in Table 1. The second part of the instrument tapped physical disability of OA patients by the Knee Injury and Osteoarthritis Outcome Score- Physical Function Short Form (KOOS-PS) questionnaire. This questionnaire is internationally developed to assess the physical disability of OA knees patients. It is a 7-item measure of physical functional derived from the items of the Function, daily living and function, sports and recreational activity. It is intended to elicit people’s opinions about the difficulties they experience with activity due to problems with their knee .
The Chi-square test will be used to assess the association between physical function score and different socio-demographic variables, chronicity of illness, number of visits and the control of the disease. All statistical analyses were conducted using Statistical Package for Social Sciences (SPSS 19.0). The study was approved by the Regional Research and Studies Ethics Committee.
Table 1 shows the socio-demographic and anthropometric characteristics of participants. Of total of 213 participants, there were 171 females and 42 males. The majority were married who aged 50 years or more. The illiterate participants comprised about 61.5%, while 31.5% had completed school education, and 7% had university education. About half of the participants had an income of more than 500 Omani Rials (around 1,299.48 USD). Overall, the anthropometric parameters indicated that about one third of participants were having normal BMI.
Table 1 also compares male and female participants in terms of socio-demographic characteristics. Overall, female participants tended to be older in age, less educated and had lower monthly income. The differences along these characteristics were statistically significant (P value <0.05).
Table 2 shows selected clinical characteristics of osteoarthritic joints among participants. This pattern was similar among male and female participants. The majority reported disease duration of less than a year, associated with chronic illness and with at least one complication. Around 12% reported positive history of trauma. The use of herbal preparation was reported by 22%, and the majority (77.5%) of herbal preparations were non-oil. Females and males had comparable clinical characteristics, except that females tended to have longer duration of disease (P value= 0.05) and more frequent visits to healthcare facility (P value = 0.02).
Table 3 shows indicators of physical quality of life among participants who have been suffering from OA. The majority have reported having at least light difficulty in getting out from bed (75%), in bending down (80%), in kneeling (78%) and in sitting cross-legged (81%). The most reported physical difficulty (about 90%) was to stand from sitting position. The least reported difficulty (23%) was putting on socks. When stratified by gender, the pattern of distribution of suffering indicators and their severity was consistent within each gender category. In comparison to males, females in general reported more severe suffering while standing from sitting position, in bending down, in kneeling, and in sitting cross-legged. The differences along these indicators were statistically significant (P< 0.05). On the contrary, males reported more suffering, compared to females, in getting out of bed (p =0.02). They also reported more suffering while putting on socks, but the difference was not statistically significant.
Table 1: Socio-demographic and anthropometric characteristics of participants, Oman, 2013.
70 or above
Monthly Income (OMR)
Body mass index
Table 2: Clinical characteristics of osteoarthritic joints, Oman, 2013.
Disease Duration (Months)
No. of Visits
Life Style (Smoking, alcohol)
Oil (local application)
Not Oil (local application)
Other (not local application)
Chronic Illness (DM, HTN, RA)
Number of complications(pain, swelling, limited movement)
Table 3: Indicators of physical quality of life among patients with osteoarthritis, Oman, 2013.
Getting out of Bed
Stand from Sitting Position
Load on Affected Knees
Sitting Cross Leg
reported history of trauma
female to male (22%vs5%, P-value 0.02)
sever pain while kneeling
female to male (22%vs12%, P-value 0.02)
having sever pain while getting out of bed
male to female (55%vs44%, P-value 0.05)
sever pain while bending
having pain getting out of bed
This cross-sectional study was conducted to describe the socio-demographic and anthropometric clinical characteristics in Omani patients with OA Knee in Oman. It pointed that OA can start at early age of 35 years, unlike some studies that showed OA starts at the age of 40 years(8,9,10). Although previous studies have suggested that OA is associated with higher BMI (19, 20), this study did not support such a view. One third of this study participants had normal BMI. In addition, this study explored the indicators of physical quality of life among patients suffering from OA in Oman. It showed that OA tended to affect more than one joint in at least a thirdof the patients, and about another third reported at least one complication of the disease. These finding reflected that OA has systematic effects that would cause physical limitations, as it affects multiple joints simultaneously. The findings also indicated the need for effective pharmaceutical and non-pharmaceutical interventions based on effective medications and modalities to improve quality of life.
Despite that the majority of participants had OA for less than a year, a substantial number of them have reported multiple joint involvement and concomitant complications. Compared to other countries, this finding showed that complications and severity of the illness could be exacerbated within a relatively short period of time from the onset. This finding might reflect the need to improve the efficiency of OA management in Oman, especially in the early stages of the disease in order prevent or at least delay potential complications.
Moreover, the study showed that use of herbal medicine was popular among the participants. This finding is similar to other reports of studies conducted in developing countries, especially Asian and Middle Eastern countries. Use of Complementary Alternative Medicine (CAM), and especially herbs, is considerably popular in these populations due to shared cultural values and believes. The society in Oman, like other Arab countries, is based on religious and spiritual values. The use of herbs has been advised in Islamic scriptures documenting the life of prophet Mohammed. In addition, and as documented in other literature, the use of CAM, including herbs continues to be a preferable option as it is perceived as safer than other modern pharmaceuticals with more reported side effects. More studies are needed to explore the beliefs and practices related to CAM use in Oman in order to articulate effective health education to the public, and to ensure safe integration of CAM in modern medical management of OA in Oman.
The results from this study, showing that women tend to suffer more than men is consistent with reports from other countries. Similar other developing countries, this finding might reflect more latency in caring for females, as they tended to suffer more illnesses and calamities compared to males. This finding would call for more health education programs at primary health care level to be directed specifically towards women in Oman.
This study has some limitations such as recall bias. In addition, catchment is not representative of the situation in the whole Sultanate of Oman. The instrument was translated but their psychometric properties was not established. The instrument tapped into physical aspect which, in turn, did not take consideration of the emotional and social sequel.
The study provides a suggestive evidence for increased prevalence of severity of the physical quality of life among patients suffering from OA in Oman. Gender plays a major role in physical quality of life as it was more prominent among females compared to males.
Many thanks for Mr. Darweesh Talib Mohammed Al bulushi and Dr. Ali Humood Al Qasmi for their help in data collection. Also, many thanks to Mr. Naser Allah Al Azri for tables.
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