Our results reported prevalence of WMSDs within a 12-month among physical therapists in HCMC, Vietnam, reaching up to 76.4%. The most commonly WMSD affected body areas were the spinal regions, the neck (58.4%) and low back (57.3%). Our results are the range of WMSDs among PTs reported in other countries [6-11,24,25], where varied from 32% to 91%. Additionally, our findings corresponded with the prevalence of WMSDs among PTs reported in Southeast Asia [11], which was 71.6%. When compared to the prevalence of WMSDs within a 12-month among other healthcare professions in Vietnam, such as physicians, nurses, technicians, pharmacists, and dentists (ranging from 62.4% to 74.7%) [3,4], PTs displayed the highest prevalence of these conditions. As a consequence, it is crucial to prioritize the prevention and management of WMSDs as a major concern in order to mitigate the impacts on physical therapists' health and improve occupational health standards in Vietnam.
Table 4. Association of environmental and psychological factors with WMSDs among physical therapists in HCMC, Vietnam (n=267)
Risk factors
|
WMSDs
|
|
Unadjusted
|
|
Adjusted by age, education
and year of experience
|
Have (n=204)
|
No (n=63)
|
|
OR
|
95%CI
|
p-value
|
|
OR
|
95%CI
|
p-value
|
Environment
|
|
|
|
|
|
|
|
|
|
|
No. PT workforce
|
|
|
|
|
|
|
|
|
|
|
<12
|
131
|
36
|
|
1.35
|
0.76-2.39
|
0.311
|
|
1.44
|
0.78-2.64
|
0.243
|
³12
|
73
|
27
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
No. of treatment table
|
|
|
|
|
|
|
|
|
|
<12
|
140
|
33
|
|
1.99
|
1.12-3.54
|
0.019*
|
|
2.32
|
1.27-4.26
|
0.006*
|
³12
|
64
|
30
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Electrotherapy room
|
|
|
|
|
|
|
|
|
|
<20 m2
|
85
|
19
|
|
1.65
|
0.90-3.03
|
0.103
|
|
2.13
|
1.10-4.12
|
0.024*
|
³20 m2
|
119
|
44
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Therapeutic room
|
|
|
|
|
|
|
|
|
|
|
<20 m2
|
53
|
16
|
|
1.03
|
0.54-1.97
|
0.926
|
|
1.43
|
0.70-2.90
|
0.330
|
³20 m2
|
151
|
47
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Pediatric rooma
|
|
|
|
|
|
|
|
|
|
|
<20 m2
|
45
|
9
|
|
1.89
|
0.80-4.43
|
0.141
|
|
2.18
|
0.88-5.37
|
0.089
|
³20 m2
|
66
|
25
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Use ultrasound therapy
|
|
|
|
|
|
|
|
|
|
Yes
|
182
|
45
|
|
3.31
|
1.64-6.69
|
0.001*
|
|
3.01
|
1.46-6.23
|
0.003*
|
No
|
22
|
18
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Use TENSE/NMES
|
|
|
|
|
|
|
|
|
|
Yes
|
170
|
42
|
|
2.50
|
1.32-4.74
|
0.005*
|
|
2.30
|
1.19-4.46
|
0.014*
|
No
|
34
|
21
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Use LASER
|
|
|
|
|
|
|
|
|
|
|
Yes
|
79
|
15
|
|
2.02
|
1.06-3.85
|
0.032*
|
|
1.80
|
0.93-3.49
|
0.083
|
No
|
125
|
48
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Use SWD
|
|
|
|
|
|
|
|
|
|
|
Yes
|
136
|
27
|
|
2.67
|
1.50-4.75
|
0.001*
|
|
2.49
|
1.37-4.52
|
0.003*
|
No
|
68
|
36
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Use shockwave therapy
|
|
|
|
|
|
|
|
|
|
Yes
|
72
|
14
|
|
1.91
|
0.99-3.69
|
0.055
|
|
1.77
|
0.90-3.48
|
0.101
|
No
|
132
|
49
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Use others machines
|
|
|
|
|
|
|
|
|
|
Yes
|
19
|
8
|
|
0.71
|
0.29-1.70
|
0.438
|
|
0.73
|
0.30-1.81
|
0.501
|
No
|
185
|
55
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Psychological factors by PSS
|
|
|
|
|
|
|
|
|
|
High stress (>5.8)
|
91
|
18
|
|
2.01
|
1.09-3.71
|
0.025*
|
|
1.91
|
1.00-3.60
|
0.047*
|
Low stress ( £5.8)
|
113
|
45
|
|
1.00
|
-
|
-
|
|
1.00
|
-
|
-
|
Abbreviation: PSS; perceived stress scale
a there were 145 physical therapists who reported the area of pediatric room.
*p-value<0.05
The association between individual factors and WMSD among Vietnamese PTs
The results also revealed a significantly association of individual factors (i.e., age, level of PT education, year of experience as PT and the specialty of hospital/clinic/center) and WMSDs within 12 months among PTs in HCMC, Vietnam. Younger PTs aged lower than 30 years were more likely to have WMSDs than those who are older which are consistent with previous findings [11-14]. Younger PTs may not know how to use self-protection strategies such as modifying treatment techniques, alternating treatment modalities, reducing demanding tasks/activities to alleviate the workload issues and have enough rest breaks between cases [12]. Align with PTs who have less years of experience in PT practice (£7 years) were more likely to develop WMSDs than those who have>7 year of experience. This study found that 97.6% (n=163/167) of PTs aged 20-29 years had less year of experience in PT practice (<7 years) and 80% of them (n=131/163) reported WMSDs within 12 months.
Interestingly, our findings found two times risk of WMSDs in Vietnamese PTs who graduated higher degree (4 years and more). This could explain by they learned more intensive courses of 4-year Bachelor and postgraduate programs and lead to PTs graduated higher academic degree take responsibility in multiple tasks in their work more than those who graduated from the 3-year Bachelor and vocational or diploma programs. Additionally, in Vietnam PTs who graduated 4-year of Bachelor’s program learn more in PT techniques such as modalities, joint mobilization and PNF techniques that have been exposed to increase the WMSD risk. These reasons lead to increase their workloads contributing to WMSDs.
The findings show that PTs who work at the hospital/clinic/center with orthopedic specialty were significantly associated with WMSDs. Orthopedic PTs were less likely to develop WMSDs when compared with general PTs (OR=0.42, 95%CI=0.19-0.89, p-value=0.025). This can be occurred because general physical therapists defined following their settings have to perform more tasks and activities than specialist PTs like orthopedic physical therapists who were clinical specialists in treatment of the musculoskeletal system. This was consistent with the finding that general non-specialized PTs had higher risk to develop WMSD [26]. Additionaly, our study found that general PTs treated more number of patients than orthopedic PTs (10.7±4.9 patients per day for general setting vs. 8.0±4.3 patients per day for orthopedic setting) which one day working is averaged 8 hours. It is acceptable to state that general PTs had a high clinical workload, so PTs who are working in general hospitals had higher risk to develop WMSDs. We recommend the organizations should redesigned workload and schedule as well as recruit more PT workforce to reduce the risk of WMSDs and lost effective workers.
The association between work-related factors and WMSD at neck and low back among Vietnamese PTs
Our findings found that performing manual therapy, implementing exercise programs, lifting or transferring, postures or positions, workload issues and personal factor were reported by PTs as the major contributing factor for WMSDs at neck and lower back. After minimizing the effect of age, education and year of PT experience, they were exposed to work-related risk factors and the risk increased to more than double times developing WMSDs at neck and lower back. Our results similar to previous studies, performing manual therapy techniques were the most common work-related risk factors contributing to WMSDs at neck and lower back problems [6,10,11]. Cromie et al., 2000 [12] found that performing manual therapy was associated with a higher risk of WMSD in neck and low back pain. Mobilization and soft tissue work and trigger point release techniques are hand-on treatment which can cause of neck and back symptoms.
Moreover, the other hand-on treatment like implementing exercise programs (i.e., PROM/AAROM, resisted exercise, passive stretching and PNF) were indicated as a risk for neck and low back problems among Vietnamese PTs. This might be a particular risk factor of WMSDs at neck and lower back among Vietnamese PTs. In addition, the new finding is that implementing exercise programs were related to neck and low back in the present study.
Our study demonstrated that neck and lower back problems related to functional activities training including ADL, gait and stair trainings. This might be explained by prolonged standing with lifting or caring patients with frequent twisting and bending when taking care patients to perform ADL, walking and stair climbing [11]. This is common cause of neck, upper-limb and lower back problems among PTs.
Lifting or transferring patients and posture/position were the most common cause of neck pain and low back pain in all kind of workers including PTs. Our findings were consistent with previous evidences [6,9, 10-12]. Those who perform lifing or carrying patients, sustain in same position or in the akward twisting position or uncomfortable postion were at high-risk of neck and lower back problems. This is base of our knowledge. However, this factor might tightly relate to knowledge and believed of physical therapists that might cause to self-believed involvement to their judgement. Therefore, it is still curiously about the true association.
Additionally, two work-related factors were identified as risk factors of WMSD at lower back which similar to the previous study [11]. Repetitive task and continuing work when having musculoskeletal injuries contributed to more than double times of lower back problem because of prolonged stress of soft tissue. In Vietnam, there are limited number of PT workforce which lead them to response to treat large number of patients per day in various conditions. This contributed to increase their clinical workloads and risk of WMSDs. Corresponded to many previous studies [5,13,20], Cromie et al. (2000) [11] found that treating a large number of patients per day was associated with a higher risk for having neck pain (OR=2.5, 95% CI=1.6-3.8) among physical therapists. Ezzatvar et al. (2020) [14] indicated that PTs who responded to treat a large of number patients at the same time were high risk of WMSDs (OR = 2.14, 95%CI = 1.53-2.99).
The association between environmental and psychological factors and WMSD among Vietnamese PTs
In this study, using PT electrical modalities including US, TENSE/NMES, LASER and SWD were identified as a risk of WMSDs among PTs in HCMC. It may be explained by shifting the working scheduling in their workplace. There are three main types of treatment room (i.e., electrotherapy room, therapeutic room and pediatric room) at the PT unit in HCMC, Vietnam. Normally, a physical therapist is assigned to work in one treatment room for a period time like a week or a month depending on the assignment of their manager. In cases, PTs work in the electrotherapy room, they might hold the ultrasound transducer during 8 hours of a workday or provide various type of PT modalities (i.e., TENS, NMES and shortwave diathermy) to consecutive patients, so they need to treat a large number of patients in a single day that lead to increase the risk of WMSDs. We recommend the organizations should arrange reasonable working scheduling for PTs, for example, assign more than one PTs in the electrotherapy room in order to support together or allow PTs indicate type of treatment and take full responsibility for the treatment of a patient to avoid performing same task over and over. Moreover, the finding showed the significant association between stress and overall WMSDs among PTs in HCMC, it was consistent with the previous findings [18,19] in details, Vietnamese PTs who had high stress were more likely to develop the risk of WMSDs.
Reactive or Coping strategies used to mitigate risk of WMSDs by Vietnamese PTs
Our study showed the responses about the self-protection to reduce WMSDs symptoms on their body whilst completing work duties. The most coping strategies were modifying the patients'/therapists' position, selecting techniques that will not aggravate discomfort, stopping treatment if it causes discomfort and adjusting the plinth/bed height before treating a patient. The coping strategies of WMSDs among Vietnamese PTs are the same as those of PTs from other countries [9,10,27,28]. Additionally, to reduce the prevalence of WMSDs among PTs, Campo et al. (2008) [29] proposed that protective measures for lifting or transferring patient should be considered and used suitable equipment such as height-adjustable beds and sliding/lifting equipment. The protevtive measures for performing manual therapy by using assistive devices (e.g., thumb splints, mobilization wedges and instruments assisted soft tissue working) and by considering only applying these techniques on patients who truly needs were also recommended. They also emphasized that the role of the Physical Therapy Association is important in formulating and promoting the prevention strategies.
Passier and McPhail (2011) [30] recommended six strategies for prevention WMSDs among physical therapists. First was an organisational strategy to manage task/workload such as defining PT roles to reduce physical demands and ensuring an appropriate workforce to help. Second was workload arrangement including physical therapists should take rest of breaks during working or while injuries, regularly perform stretching exercises on targeting muscles affected, and plan an acceptable number of patients treated by physical therapists per working hour per day. Third, physical therapists should allow to modify treatment techniques to avoid injuries or aggravate the symptom. Fourth, work setting and provision of equipment suitable for appropriate purpose and sufficient quantities. Fifth focused on improving overall physical health, maintaining a healthy lifestyle, engaging in regular physical activity outside of work, managing stress and having schedule check-ups with professionals to address any health issues especially discomfort or pain. Sixth was education and training physical therapists can attend workshop or training sessions for proper body mechanics and injury preventions during working.
Limitations
This study had some limitations that need to be acknowledged. Firstly, being an online self-reported cross-sectional survey, there might have been a potential for recall and information bias among participants. However, to mitigate these issues, we provided clear descriptions and examples in the questionnaire, and participants were encouraged to provide honest responses. Secondly, the data collection occurred during the COVID-19 outbreak in HCMC, Vietnam, which could have influenced respondents' answers. Some PTs may have experienced changes in their tasks and settings due to the pandemic's impact. During the three-month lockdown from July to September 2021, PTs were redirected to support the treatment of COVID-19 patients, leading to a high clinical workload and potential challenges in developing WMSDs. Despite these circumstances, we explicitly instructed respondents to base their answers on their usual work-related activities as PTs.