Kitchen work is a high-risk occupation for WRMSDs due to poor work environment, the intensive manual workload, and repetitive movements that are involved. The present study revealed that the majority of kitchen workers (90.6%) at the students’ hostel reported WRMSDs within the past 12 months.

The high prevalence of WRMSDs in the present study was similar to many studies conducted among kitchen and restaurant workers in Finland [17] (87%), Taiwan [18] (85.2%), Ethiopia [19] (81.5%), and Bangladesh [20] (78%). In contrast, the present finding was higher than studies conducted among kitchen workers in Spain [21] (69.2%), India [22] (67.5%), and Turkey [23] (59%).

The first possible reason of this contradiction is that kitchen workers in the present study are exposed to a more extensive manual working process as they are used to work under pressure serving a large number of meals every day at the students’ hostels which would induce higher degrees of exhaustion. The second reason could be the presence of poor occupational health and safety services in Egypt compared to other countries due to inadequate health and safety experts which would lead to poor and unsafe work environment, inadequate use of personal protective equipment (PPE), and poor knowledge among kitchen workers. A third possible explanation could be a variation in the assessment tools. A self-reported interview questionnaire was used in the present study. However, different study tools such as an ergonomic measurement tool was used in the Indian study [22] for instance. The fourth explanation might be due to the inclusion of kitchen workers with mean age (44.8 ± 8.24) which is higher than other studies as for instance the study carried out in Taiwan [18], where the mean age among cookers was 33.3 ± 11.3 years. In the current study most of the study participants were older than 30 years with the nearly half of the participants (49.2%) between 40 and 50 years. The older age of kitchen workers is attributed to the hiring freeze of new workers in the governmental sector in Egypt as it is saturated with the current employees who are growing older nowadays and are exposed to a higher prevalence of WRMSDs. As workers grow older, they are exposed to the diminution of bone density which begins at the age of 30 years. Low back and knee pain subsequently become more common.

The present study reported that the lower back (64.8%), knee (46.9%), foot (46.1%), neck (29.7%), and shoulders (23.4%) were the most affected parts during the previous 12 months.

The presence of low back pain as the chief complaint for kitchen workers was also reported in similar studies conducted in India [22] (65.8%), Ethiopia [19] (53.55%), Finland [17] (50%), and Malaysia [14] (43.3%), but higher than the studies conducted in India [24] (43%), Bangladesh [20] (38%), and Taiwan [18] (32.7%). The possible reason might be attributed to different participants’ characteristics and variations in workload. The percentage of low back pain in kitchen workers was higher than other occupations that did not require manual handling as computer workers [24] where the prevalence rate of lower back pain was reported as 40.4%, Also, the percentage was higher than a sample of Egyptian female hairdressers where the prevalence rate of lower back pain was 12.5% [25]

In addition to that, similar percentages for other body parts affected with MSDs was reported in a study done among restaurant workers in Ethiopia [19] where the percentages of discomfort or pain in the neck was (36.1%), shoulder (44.7%), hips/tights (33.6%), knee (40.7%), and ankle or foot (41.3%). In India [22] the shoulder region (62.3%), knee/foot (42.1%), neck region (38.6%), elbow/forearm (31.6%), and thigh (30.7%) were also among the most common affected body parts. This was higher than studies done in Taiwan [18], Bangladesh [20], Spain [21], and Turkey [23] among restaurant workers and the study done among hairdressers in Egypt [25]. Kitchen workers are exposed to MSDs in many body parts as compared to other occupations as restaurant workers’ tasks necessitate repetitive and forceful motion of the hand, raised shoulders, and bending of the back; these working postures induce pain in both lower and upper body parts. In addition to that, restaurant workers perform tasks in a static standing position for long duration leading to pain in the leg muscles.

Concerning risk factors of MSD in the studied kitchen workers; the present study revealed that age, educational status, job category, job duration and BMI were significantly associated with WR MSDs among kitchen workers.

Concerning the relationship between age and WRMSDs, the present study found that the prevalence of WRMSDs significantly increases as the participants’ age increase. This finding is supported by studies done by in Ethiopia [19], Bangladesh [20], South India [22], South Korea [26], and Iran [27]. The possible clarification is that biological structures of the human body, particularly related to muscles, joints, nerves, ligaments, and tendons degenerate as the ages of the workers increase in addition to diminution of bone which would provoke pain and result in higher tendencies of WRMSDs development.

The present study found that restaurant workers who were illiterate or attended primary and preparatory education were at higher odds of developing WRMSDs compared with those at a higher educational level. Manual work is usually assigned to low educated persons. Furthermore, education level was negative predictor for occurrence of work-related musculoskeletal disorders as education level improve the human knowledge about health. This is similar to a study conducted in Ethiopia [19], where the odds of developing WRMSDs among respondents who were illiterate or completed the primary levels of education were 1.79 and 2.14 times, respectively, than that of those who completed higher education. This finding is supported by a study conducted in Egypt [28] which showed that improving workers’ knowledge and practice regarding work-related musculoskeletal disorders could significantly minimize the burden of MSDs among Kitchen workers.

A statistically significant relationship was found between job category and WRMSDs, where cooks, cooking assistants, laborers and food presenters experienced MSDs at a higher percentage in the previous 12 month. This could be explained the heavy workload they had to perform. Their job necessities heavy lifting, repetitive monotonous work, awkward position, and long working time standing. In addition, there is a shortage in the number of the before mentioned job categories and their ages is mostly above forty. Also, job categories were positive predictors for occurrence of work-related musculoskeletal disorders. This was consistent with the results obtained from a study done in India [22] among kitchen workers; where chief cooks (79.2%) and assistant cooks (74.3%) reported highest MSDs.

This study revealed that job duration is an important work-related risk factor for musculoskeletal complaints. This is consistent with the results from studies done by in Kuwait [16], Taiwan [18], and Iran [27].

The current study also reported that higher BMI was associated with incidence of WRMSDs. This was similar to the studies done in Ethiopia [19], Taiwan [18, 29], Finland [30], Iran [27], Norway [31], and Canada [32]. In the study done in Iran [27], workers with higher BMI experienced a significantly higher rate musculoskeletal problems (P<0.001). Also, in Ethiopia [19] the odds of developing WRMSDs among kitchen workers with higher BMI were 1.14 than those with lower BMI. Participants in the study done in Taiwan [29] with BMI>27 kg/m2 were more likely to suffer from MSDs.

One of the limitations of this study was the possibility for recall bias due to the reliance on a self-reported questionnaire to collect data. However, we believe that this limitation has insignificant impact on our findings as the Nordic Musculoskeletal Questionnaire (NMQ) has been proven to have adequate reliability and validity. Furthermore, the sample was heterogeneous (It included chefs, cooking assistants, laborers, supervisors, administrative and maintenance workers with different pattern of work which could affect both occurrence and location of pain or discomfort).