INTRODUCTION
Osteoarthritis (OA) once considered a consequence of aging; OA could
be found in moving joints, especialy affect the large weight-bearing joints
such as the knee, hip and spine. When OA with clinical symptoms, such as
pain, physical disability and limiting daily activities, which makes the
patients have to see a doctor regularly and be treated. Therefore, this affects
the quality of their life and causes economically costly.
According to a survey conducted in USA, more than 80% of over 55
year-old people show signs of OA on X-ray, in which 10 - 20% of
people have limited mobility. Especially, a few hundred thousands of the
people are not self-serviced due to hip OA and the cost of treating one
patient with drugs was amounted to USD 141.98 in 30 days. In France,
OA accounts for about 28.6% of the musculoskeletal disorder, each year
about 50,000 people are replacemented artificial hip joints.
Along with the increase in average life expectancy of Vietnamese,
musculoskeletal disorder, especially knee OA is common, the more
elderly people are the more severe disease are. This disease does not
directly threaten to the patients’ life so patients and the community has
not paid adequate attention to it, especially manual labors in rural areas.
If this disease is detected and treated late, the result of treatment is not
effective as expected, associated with leaving jobs, reducing labor
productivity and limit daily activities, even leading to lifelong disability.
Therefore, the role of community health workers is very important in the
early detection, proper treatment and counseling for the people.
In Vietnam, there have been research works on the clinical
characteristics and treatments on knee OA in a number of hospitals, but
epidemiological assessment of knee osteoarthritis and diagnose as well as
treatments and counseling for knee OA patients in the community still
received little attention. To make this issue be understood better, we
carried out the thesis: "Study of knee osteoarthritis and improving
capabilities of diagnosis and managements of community health

Knee joint is a hinge joint between the bulging of the tibia, femur, and
patella with the face of patella of femur. This is a complex joint with
very wide synovial fluid, easily swollen and distended. Knee joints in
prone areas are easy to be impacted and injurred.
Knee joint is a complex joint consisting of two joints:
- Between the femur and tibia (the hinge joints)
- Between the femur and the patella (the flat joints)
1.1.3. The structure and composition of articular cartilage.
Articular cartilage is white, smooth, elastic wrapped around the
epicoldyle of femur, tibia, and the back patella. Articular cartilage with
physiological functions is to protect the epiphyseal of the bones and
spread out the weight bearing on the entire joint surface. Normally,
articular cartilage is glossy, wet, very hard and strong elastic. The
articular cartilage ensures sliding motion among the articular surfaces
occurring with a very low coefficient of friction, as a buffer layer helps
to reduce compression. Articular cartilage has no blood vessels and
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nerves. The basic composition comprises the cartilage cells, collagen
fibers and basic chemicals, and arranged and form different layers.
1.2. Osteoarthritis
1.2.1. Definition
Osteoarthritis is the dysfunction of articular cartilage, the main
manifestation of this disease is the phenomenon of wear and tear of
articular cartilage in relation to minimizing the mechanical operation of
the joint. OA is the result of the mechanical and biological proccess,
which causes the imbalance between synthesis and destruction of
cartilage and subchondral bone (the spine and intervertebral discs).
1.2.2. Epidemiology of osteoarthritis
Osteoarthritis is a common musculoskeletal disease. Among the

catabolism of cartilage degeneration and basic chemicals.
1.2.4. Symptoms of knee osteoarthritis.
 The main symptom:
- Pain that increases when you are active, relieving when having a
rest, limitation of mobility, stiffness of the knee, etc.
- The majority of joints are not swollen, no heated, may deform due
to the enlargement of spines and fat around the joints, limited the range
of the knee joint, especially, knee folding actions, with the pain in the
patella slots - pulley, - ball pulley; signs of wood shavings; bony
enlargement etc.
 Diagnostic criteria of knee osteoarthritis basing on clinical
symptoms of the American College of Rheumatology (ACR-1991)
1) Pain in the knee.
2) Crepitus on action motion.
3) Stiffness of the knee less than 30 minutes
4) Age ≥ 38
5) Touching the bony enlargment
Diagnosis identified when having factor 1,2,3,4 or 1,2,5 or 1,4,5.
1.2.5. Treatments to OA:
 Principle: Slowing the process of joint destruction, especially to
prevent the degradation of articular cartilage, pain relief, mobility
maintaining, minimizing the disability.
 Medical treatments:
- Using of non-pharmacological methods, avoiding the overloading
for the knee joint due to movement and weight.
- Pain relievers and anti-inflammatory drugs, such as acetaminophen,
non-steroid anti-inflammatory drugs and corticosteroids (intra joint
injections).
- Supplement, including Glucosamine Sulfate, Chondroitin Sulfate, etc.
- IL 1 inhibitor, such as artrodar;

when they are ill, is very low despite a large team of health workers. The
situations about the capacity of the health workers is still a matter needed
to be concerned. Most medical workers in CHCs are still lack of
knowledge and skills, especially the ability to examine and detect
common diseases early.
1.4.3. The abilities of diagnosis and management of knee OA at the
CHCs.
Currently, together with the increase in average life expectancy of
people in Vietnam, musculoskeletal diseases, especially knee OA is
common, the more elderly people are the more severe the diseases are.
After the age of 40-50, manifestation of the disease may appear, and
women easily get down this disease twice as often as men. If being
detected and treated late, the treating effect is not as expected. It is
associated with leaving jobs, reducing labor productivity and limit daily
activities, even to lifelong disability. Therefore, the role of health
workers at the grassroots levels is vital in the early detection, proper
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treatment and counseling for people. Whether medical workers have
sufficient knowledge, detection skills, diagnosis and early treatment for
knee OA in the community or not is an issue that needs to be addressed.
According to a survey in Malaysia, most primary doctors order
unnecessary tests for the diagnosis of OA. X-ray images can help in the
diagnosis and severity of illness, but not always parallel with the clinical
manifestations, in some cases people with X-ray evident of OA but no
clinical symptoms. In the diagnosis proccess to identify OA, blood tests
are not worthy much, however, more than 50% of physicians at CHCs
ordered to specify blood tests, such as rheumatoid factor, uric acid,
ANA, etc. to diagnose the OA. This can easily lead to misdiagnosis as
rheumatoid arthritis or lupus if the RF tests or antinuclear antibodies

treatment and counseling for the knee OA patients, which also
contributes to good health care for rural residents.
2.2.2. Sample size estimation
* The sample size of the cross-sectional study
- Content 1: Determining the incident, clinical characteristic description, X-
ray and a number of related factors to the knee OA in people aged 40 years or
older in 02 communes of Gia Loc district, Hai Duong province, applying the
formula of the sample size for cross-sectional descriptive study:

( )
2
2
2
2/1
x
p
pqZ
n
ε
α
−
=
n: number of individuals in the study sample
p: estimated propotion of OA (p = 0.3 estimated by the study of
Nguyen Thi Nga).
q: the offset to 1 of p (q = 1 - p)
Z
1-
α
/2

- Training collaborators to data collecting information by
rheumatology specialtist doctor of Bach Mai Hospital
- Conducting a pilot survey and completing questionnaires.
- Data Collecting.
2.2.5. Data analysis:
Data was processed and analysed by SPSS program 7.5. The research
results are calculated and presented in numbers and percentage (for qualitative
variables), the average value (for quantitative variables). Comparison was done
before and after the intervention by statistical hypothesis testing (p value) and
considers the magnitude of the efective indicators.
2.3. Research Ethics:
The proposal must be approved and decided by the commitee of Hanoi
Medical University and Ministry of Education and Training
CHAPTER 3. RESULTS
3.1. Describing the characterisstics of knee OA in people aged 40 and
older from 02 communes in Gia Loc district, Hai Duong province in 2008.
Figuge 3.1:
Percentage
of knee OA
(ACR
criteria in
1991 basing
on history and physical examination)
Comments: According to the investigated 2153 people aged 40 and
over, we found 584 of those with knee OA (27.1%).
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27,1%
72,9%
Knee OA

Not enough
symptoms of knee
OA on physical
examination
Total
n % n % n %
Male 93 18,4 413 81,6 506 100
Female 491 29,8 1156 70,2 1647 100
p OR = 1,60 (1,33 – 1,97), p<0,05
Comments: The prevalence of knee OA in female is higher than
male (29.8% compared with 18.4%).
Table 3.3: Relation between knee osteoarthritis and BMI
knee OA
BMI
(kg/m
2
)
Knee OA based
on physical
examination
findings
Not enough
symptoms of knee
OA on physical
examination
Total
n % n % n %
BMI < 23 456 25,8 1310 74,2
176
6

Knee OA
based on
physical
examination
findings
Not enough
symptoms of
knee OA on
physical
examination
Total
n % n % n %
40 - 49
Menstrual 81 17,6 380 82,4 461 100
Menopause 12 20,7 46 79,3 58 100
p > 0,05
50 - 59
Menstrual 33 36,7 57 63,3 90 100
Menopause 103 27,5 272 72,5 375 100
p < 0,05
Comments: The results showed that the prevalence of knee OA in
menopause women increases comparing with menstrual women at all age groups.
Table 3.6: Knee osteoarthritis with a history of childbearing
Knee OA
History of childbearing
By age groups
Knee OA
based on
physical
examination

≥ 3 children 144 45,4 173 54,6 317 100
p < 0,001
Comments: The results indicated that in the group aged 50 above,
women with 3 or more children manifesting clinical knee osteoarthritis
are higher than women with 2 children or less.
Table 3.7: Knee osteoarthritis with the nature of work
Index
Knee OA based
on physical
examination
findings
Not enough
symptoms of knee
OA on physical
examination
Total
n % n % n %
Heavy carrying
- Yes 539 31,6 1168 68,4 1707 100
- No 45 10,1 401 89,9 446 100
p OR = 4,11 (2,97 - 5,68), p<0,001
Regular walking
- Yes 482 32,6 995 67,4 1477 100
- No 102 15,1 574 84,9 676 100
p OR = 2,75 (2,17 – 3,49), p<0,001
Comments: The prevalence of knee OA in the people carrying heavy
weight is remarkably higher than those carrying lightweight (31.6%
compared with 10.1%). Similarly, for the people walking to work
primarily, this rate is also higher than those with less walking to work
(32.6% compared with 15, 1%) p <0.001.

66,1 666
10
0
p OR= 1,19 (0,973 - 1,48), p <0,05
Comments: Knee OA percemtage in the people carrying weight ≥
50 kg / 1time is higher than in those carrying under 50 kg per 1 time
(33.9% compared with 30%).
3.2. Commenting on the knowledge of diagnosis and treatment to knee
OA of health workers in the CHCs in Hai Duong province.
Table 3.9: Description of knowledge on knee OA diagnosis of health
workers at CHCs.
Result
Diagnosis
Quantity
Percentage
(%)
Initial
Diagnosis
Rheumatoid Arthritis 94 32,4
Osteoarthritis 214 73,8
Septic arthritis 15 5,2
Rheumatic fever 20 6,9
Lupus 10 3,4
Total 290 100
Tests
X-ray 248 85,5
CBC 194 66,9
Liver function tests 26 9,0
Immunological tests 37 12,8
Synovial fluid tests 84 29,0

proportion of health workers opting for antibiotics (14.8%) and oral
corticoit (17.9%) for the treatment of OA.
Table 3.11: Description of knowledge of health workers in counseling osteoarthritis
Results
Counseling contents
Quantity
Percentage
(%)
Weight reduction (if obesity) 185 63,8
Reduce exercise if feeling painful 162 55,9
Do not squat 149 51,4
Avoid carrying heavy weight 239 82,4
Reduce standing, walking, climbing stairs 129 44,5
Increase exercise if feeling painful 34 11,7
Increase walking, climbing stairs 66 22,8
Total 290 100
Note: A health worker can select more than one advisory content
Comments: The health workers with the sufficient knowledge can
give right advice for the knee osteoarthritis patients such as avoiding
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carrying heavy loads, weight reduction if overweight, reducing exercise if
painful, reducing standing and walking (respectively 82.4 %, 63.8%,
55.9%, 51.2% and 44.5%). There are 11.7% of health workers advising
knee OA patients to increase exercise and 22.8% of health workers advise
patients to enhance standing, walking when feeling painful in knee joint.
3.3. Evaluating the effectiveness of interventions
Table 3:12: Effectiveness of interventions of diagnotic knowledge to knee OA
Results
Level

(%)
p
Effective
indicator
(%)
Good 44,1 47,2
p < 0,05
7
Poor 55,9 52,8 -6
Comments: The percentage of health workers in communes
equipped the good knowledge on treating knee OA increased
significantly from 44.1% to 47.2% Effective indicator = 7% and the
proportion of health workers in communes having the poor knowledge
on diagnosing knee osteoarthritis significantly reduced from 55.9% to
52.8%; Effective indicator = - 6%.
Table 3.14. Assesss on consulting knowledge of knee osteoarthritis
Results
Level
Pre
interventio
n (%)
After
intervention
(%)
p
Effective
indicator
(%)
Good 42,1 67,6 p <
0,001

symptoms of knee OA, including a higher incidence in the elderly and
women and African Americans have incidence knee OA severe higher
than white ones.
Prevalence of knee OA in weight-bearing ones usually much higher
than those who do not regularly carry heavy loads (31.6% compared with
10.1%). Similarly, the prevalence of knee OA in the people walking for
many hours a day was mostly higher than these were not walking much
(32.6% compared with 15.1%). However, we cannot confirm that this is
the cause of knee OA or due to knee OA, patients’ limited physical
activities or limited heavy lifting. This may be a limitation of the cross-
sectional study.
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This result is consistent with the conclusions of M.Rosignol (2005),
the most significant occupations, which related to the high prevalence of
knee OA were cleaning women workers (OR 6.2, 95% CI 4.6 - 8.0),
industrial tailoring, male construction workers and farmers (OR: 2.8,
95% CI 2.5 to 3.2). The study also showed that the features of OA occur
in 40% of those who have to do the hard work and often appear the first
symptoms of OA before the age of 50. Andreas Seidler et al (2008)
carried out a case-control study in 295 OA cases with X-ray images and
327 controls in men about the relationship between kneeling, squatting,
and lifting or carrying of heavy loads and knee OA symptoms.
According to the authors, there is an association between the kneeling or
squatting position with symptomatic knee OA, the total time kneeling
and squatting over 10,800 hours, which the OR of X-ray was 2.4 times
(95% CI : 1.5 - 5.0).
Thus, in order to reduce OA related to the occupational, we should to
pay attention to reduce the kneeling, lifting or carrying heavy loads
activities as well as other risk factors of OA.

Kellgren and Lawrence criteria) in women quicker than in men. Beside of
that, the average level of pain (by WOMAC criteria) in women were severe
than men with the same stage of the X-ray.
In contrast to these results, the study of Rosie J Lacey on 745 OA
patients showed that men with OA represents the X-ray evident more
than they represents in women (77% compared with 61%), especially in
middle age and in femur and kneecap joint.
In general, each author found a distribution rate of different gender,
but almost same as OA is more common in women than in men. This has
not yet satisfactorily explained, some authors suggest that the hormonal
changes in women make them more susceptible to knee OA.
- Body mass index (BMI):
Results showed the prevalence of knee osteoarthritis increases
proportional with BMI. The OR of knee OA was 1.4 times higher in the
group with BMI ≥ 23 compared with group with BMI <23. High BMI
bear much load on the knee when walking, that make the knee OA
rapidly.
Ray Marsk’s study (2007) showed that high BMI increases the risk of
knee OA in both side as well as the hip OA. Similarly, an longitudinal
epidemiological study in 20 years of Margreth Grotle et. al. in 1854 people
from 25 to 76 years old showed that when BMI> 30 is a predictor of knee
OA (OR 2.81, 95% CI: 1.32 - 5.96) and hand OA (OR 2.59, 95% CI: 1.08 -
6.19). In addition, studies of Andrew K Wills and colleagues showed that
the relationship between BMI and OA after 20 years in men and n is 15
years in wome. Beside of that, the change BMI from childhood in women
and from adolescence in men is also closely related to knee OA.
Felson et, al. found that the reduction of excess weight in middle-aged
people have the effect of substantially reducing the risk of knee OA
symptoms. Hart and Spector detemined the relationship between obesity
and body fat distribution in knee OA women in a residential area has

The increase in the incidence of OA after joint injury requires attempt
solutions to prevent knee injuries in order to improve people's health;
joint injury prevention can reduce from 14-25% incidence of OA.
- Menstrual status:
Results of the study showed that in menopause women, the incidence
of knee OA increases with age (≥ 40 years: 20.7% ≥ 50 years: 27.5% ≥
60 years: 39.9 %, ≥ 70 years: 39.2%). According to some authors found
that under the age of 55, the incidence between men and women is
almost equal. However, after 55 years, the incidence is much higher in
women than in men. This suggests that there may be correlation between
menopausal status and knee OA.
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Asokan GV et. al. (2011) reviewed 420 women aged 40 or older with OA,
of which, 68% were menopause. Are oetrogen against OA or not? Currently
there is no answer yet to this problem, but the authors have found correlations
among hypertension, hypercholesterolemia, hyperglycemia (the common
diseases in menopause women) with knee OA.
Spector et.al. suggested that middle-aged women, especially after
menopause were high risk of knee OA. In addition, the authors also
found an association between high blood sugar and cholesterol levels
with knee OA. This led to the hypothesis that physical factors and
hormone metabolism are associated with disease. In the Framingham’s
study found among women with a history of ovarian cut up had high
prevalence of knee OA.
Dang Hong Hoa studied in Vietnam showed that, the prevalence of
knee OA in menopause women accounted for 80.6%, higher than the
group of women who are menstruating (19.4%). So far the role of
menopause for knee OA has not been confirmed, so these are
suggestions for further research on this issue.

patients with knee OA showed that 75% of general physicians surveyed
would arrange an X-ray, 65% of general practitioners (GPs) surveyed
would arrange a blood test, mostly serum uric acid, rheumatoid factor
and ESR.
- Knowledge of OA treatment, it is showed that a number of health
workers selected appropriate treatment such as paracetamol, non-
steroidal anti-inflammatory, massage (50%). However, there was still a
significant proportion of the health workers choosing antibiotics or oral
corticosteroids for the treatment of OA (14.8% and 17.9%). This is
probably a result of not understanding the pathophysiological of OA as
well as the abuse of antibiotics and corticosteroids, which could negative
consequences for the patients.
According to research results in Malaysia, it is indicated that
pharmacological management consists of first line treatment with
analgesics (32%), NSAIDs (59%) or a combination of the two (4%).
89% of GPs surveyed prescribed some form of complementary
medications. 68% prescribed glucosamine sulphate, 29% chondroitin
sulphate, 18% cod liver oil, 12% evening primrose oil. Only 5% of GPs
surveyed perform intra- articular injection. In addition, the study also
showed that up to 95% of GPs do not know about the national guidelines
for the treatment of OA.
- Counseling knowledge for knee OA patients, health workers also
have basic knowledge of counselling for knee OA patients, such as
weight reduction if overweight, reduce physical activities if have knee
pain, and especially avoid squating or heavy lifting. Since these are
factors increase compression, which made up cartilage damage faster and
more severe. Nevertheless, there were a number of health staffs advising
patients that walking more when they had knee pain (22.8%). This is the
misconception of treatment, because one of the causes of knee OA is
walking too much.

on OA management for primary care physicians in the United States
shows that GPs were not trained about the basics of musculoskeletal
diseases and very rare to be re-trained after graduation. After
implementing a mentoring program for GPs by specialty OA physicians,
results at 1 year showed average knowledge and skills of GPs before
training was 58.2%, which increased to 84.1% after training.
According to research by Le Van Them (2003), up to 93.5% of the
physicians worked in CHCs were trained in in-service training system
and their professional was general practitioner. Of whom, 50% reported
that, the in-service medical doctor’s curriculum was not enough
knowledge and skill to help them carry out the health care and disease
prevention, especially specialties. Besides, only 43.5% doctors were
trained at least one time after graduation, mainly about reproductive
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health, health care management, traditional medicine, pediatric primary
health care, etc. Thus the numbers of CHCs’ doctors trained after
graduation is very low and the training content is not appropriate for
their functions that they undertake at CHCs. So maybe this is also a
factor affecting the selection of diagnosis and management of knee OA
in the community should considering for further research. The author
also recommends regular updates and training knowledge and skills in a
number of common diseases for doctors of CHCs is very important to
improve the quality of health care services at CHCs.
Result of intervention study showed that health care workers
significantly increased in knowledge of knee OA diagnosis at good and
very good levels; and the numbers of health care workers lack of knee
OA diagnosis knowledge significantly decreased from 72.8% to 51.0%.
Similarly, the percentage of health workers, who had good knowledge
of knee OA treatment increased from 44.1% to 47.2%; and the

- Knowledge of knee OA consullting: 42.1% of health workers were
good knowledge, 57.9% were poor.
5.2.2. Effectiveness of interventions of knowledge on knee OA
management for CHCs staffs after 1 year:
- Knowledge of knee OA diagnosis: percentage of health workers with
good knowledge quite increased (effectiveness indicator = 80%) and the
proportion of health workers with poor knowledge remarkably reduced
(effectiveness indicator = -30%), p <0.001.
- Knowledge of knee OA treatment: percentage of health workers with
good knowledge increased slightly (effective indicator = 7%) and the
proportion of health workers with poor knowledge reduced (effective
indicator = -6%), p <0.001.
- Knowledge of knee OA consulting: the percentage of health workers
with good knowledge increased (effective indicator = 60%) and the
proportion of health workers with poor knowledge reduced remarkably
(effective indicator = -44%), p <0.001.
RECOMMENDATIONS
Based on result of the study, we would suggest some
recommendations as follows:
1) Providing information about knee OA and the factors associated
with knee OA for the rural population in order to improve the quality of
life.
2) Applying ACR diagnostic criteria in 1991 based on the history and
physical examination findings for epidemiological investigation and
initial diagnosis at grassroot level. However, in order to confirm
diagnosis of knee OA, we should apply ACR criteria (1991) based on
history, physical examination and laboratory findings.
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3) Strengthening training and re-training for health professionals