This study found that most pilgrims were at a high risk of experiencing musculoskeletal pain during the Hajj. The most prevalent forms of musculoskeletal pain among pilgrims were ankle/foot pain, leg pain, low back pain, knee pain and shoulder pain. The findings of this study confirmed significant associations between the prevalence of musculoskeletal pain and demographics, major medical history, beliefs about the Hajj, falls and receiving treatment during the Hajj.
Musculoskeletal pain (pain at any anatomical site)
The majority of pilgrims (82.27%) had at least 1 musculoskeletal complaint during the Hajj. This high prevalence rate was in consistent with the findings of previous studies among different populations, such as occupational drivers in Nigeria (89.31%) [34], the working population in New Zealand (92%) [35], nursing assistants in Norway (88.8%) [36], physiotherapists in India (88%) [37], dentists in Iran (73.17%) [38] and Greece (62%) [39], agricultural farmers in Nepal (70%) [40] and bariatric surgeons around the globe (66%) [41]. Our findings differ from those of studies that reported lower rates of musculoskeletal pain, such as the general population in the Netherlands (53.9%) [42], construction workers in Saudi Arabia (48.48%) [43], the Quebecois working population in Canada (41.43%) [44], the older population in the United States (40%) [45] and the general populations in Sweden (23.9%) [46], Brazil (21.6%) [47] and Japan (15.38%) [48].
The prevalence of musculoskeletal pain (pain at any anatomical site) in the current study was greater in females and older individuals. These findings are consistent with those of previous studies that reported a higher prevalence of musculoskeletal pain in females than in males in Brazil [47], Japan [48], Sweden [46], the United States [45] and worldwide [49, 50]. Furthermore, several studies have yielded findings similar to ours, revealing that age is a risk factor for musculoskeletal pain. These studies reported that musculoskeletal pain was more common in individuals aged ≥ 60 years than in younger individuals in different countries [46, 47, 50]. However, our findings differ from those of studies that found either no significant association between age and musculoskeletal pain [35, 43] or that adults had a higher risk of musculoskeletal pain than individuals over 60 years old among the general population in Japan [48]. There was no significant association between BMI and musculoskeletal pain among pilgrims in our study, whether with a crude or an adjusted OR. This result was similar to that of a study conducted among construction workers in Saudi Arabia, which found no association between BMI and musculoskeletal pain [43]. On the other hand, our findings differ from those of Bezerra et al. (2018) [47] and Abdulmonem et al. (2014) [51], who reported that musculoskeletal pain was more common in those with greater BMIs than in those with a normal weight in Brazil [47] and Saudi Arabia [51]; however, these studies did not adjust for potential confounding factors.
In the current study, musculoskeletal pain was more common overall in individuals who smoked, had diabetes and hypertension, believed that the Hajj is physically exhausting, had experienced a fall during the Hajj and/or had received treatment during the Hajj. These findings were in consistent with some other previous studies reporting that smoking [47], diabetes [27], depression [45, 47] and falls [45] were risk factors for musculoskeletal pain among the general and older populations. However, our study differs from a few studies that did not find significant difference between smokers and non-smokers in terms of musculoskeletal pain among construction workers in Saudi Arabia [43]. Our study also found that 24.31% of pilgrims obtained medical care due to the musculoskeletal pain they felt during the Hajj. This result was similar to those of studies that found a significant proportion of the individuals with musculoskeletal pain among diverse populations reported seeking medical care [39, 41–43].
Sex- and age-based differences in musculoskeletal pain prevalence
In our study, the largest difference between males and females was observed for low back pain (males: 25.11%, females: 32.20%) and leg pain (males: 27.17%, females: 34.09%) among pilgrims. There are large demographic differences for most anatomical sites of pain, with the largest differences being between males and females in the literature. In the Netherlands, the largest differences between males and females were observed for neck pain (males: 15.7%, females: 25.4%) and shoulder pain (males: 16.2%, females: 25.6%) among the general population [42]. In Canada, the largest difference between the sexes was observed for neck pain (males: 11%; females: 18%) among the Quebecois working population [44]. In New Zealand, the largest differences between males and females were observed for upper back pain (males: 15%, females 23%) and shoulder pain (males: 38%, females 46%) among the working population [35]. In Norway, the largest sex-based difference was observed for hip pain (males: 16.2%, females: 27.1%) and shoulder pain (males: 36.8%, females: 47.5%) among nursing assistants [36].
In our study, the prevalence of musculoskeletal pain was higher in older pilgrims than in younger pilgrims at multiple pain sites. The largest difference between younger and older pilgrims was observed for knee pain (18–29: 14.75%, ≥ 60: 41.77%) and low back pain (18–29: 25.59%, ≥ 60: 37.97%). These findings differ from those of previous studies in the literature. In the Netherlands, the largest differences between younger (25–44) and older (≥ 65) individuals were observed for wrist/hand pain (25–44: 11.3%, ≥ 65: 22.5%) and hip pain (25–44: 5.6%, ≥ 65: 21.2%) [42], but these large differences were only observed in females. In Norway, the largest differences between younger and older individuals were observed for head pain (< 30: 54.2%, ≥ 60: 24.7%) and knee pain (< 30: 13.3%, ≥ 60: 29.3%) among nursing assistants [36]. In our study, ankle/foot pain was more common in younger (18–29: 42.71%) than in older (≥ 60: 36.08%) pilgrims, whereas low back pain was more common in pilgrims aged over 60 years. These results differ from those of a study conducted in the Netherlands, which found a slight decrease in lower back pain with increasing age [42].
Musculoskeletal pain of the spine
In our study, the most common musculoskeletal pain of the spine among pilgrims was low back pain (28.40%). This result is similar to those of several studies that reported similar low back pain prevalences, such as among agricultural farmers in Nepal (36.18%) [40], dentists in Iran (33%) [38], the general population in the Netherlands (26.9%) [42], construction workers in Saudi Arabia (24.24%) [43] and the general population in Sweden (22.97%) [46]. However, the prevalence of low back pain in our study was slightly lower than that reported in other studies, which reported higher rates of low back pain in school teachers in Saudi Arabia (66.87%) [51], occupational drivers in Nigeria (64.78%) [34], physiotherapists in India (61.50%) [37], nursing assistants in Norway (54.9%) [36], the working population in New Zealand (54%) [35] and dentists in Greece (46.05%) [39].
In terms of potential risk factors, we found that low back pain among pilgrims was more common in females, older (≥ 60) and obese (BMI: ≥30) pilgrims, pilgrims who smoked, those who had diabetes (close to the margin of significance) and hypertension, those who believed that the Hajj is physically exhausting and those who received treatment during the Hajj. These findings are similar to those of several studies that found females were at a higher risk for low back pain than males among the general populations in the United Kingdom [52], the Netherlands [42] and Sweden [46]. However, our findings differ from those of studies reporting that low back pain was more common in males than females among the working population in New Zealand [35]. Furthermore, our findings are similar to those of studies that found an association between the presence of chronic disease [51], anxiety [44, 51] and depression [44, 51] and low back pain. In contrast, other studies also reported no significant association between low back pain and sex [36, 39, 44, 53], age [36, 39, 44, 51, 53], BMI [51, 53] and smoking [39, 44, 53], although some of these studies found significant differences in neck pain based on sex [36, 39, 44], age [39, 44] and smoking status [44]. We found a higher risk of falls among pilgrims who suffered from pain at several spinal sites, including head, neck and thoracic pain. This is in contrast to the older population in the United States, among whom there was no significant association between falls and back pain [45].
Musculoskeletal pain of the upper limb
In our study, the most common form of musculoskeletal pain of the upper limb among pilgrims was shoulder pain (16.09%). This result is similar to those of several studies reporting similar shoulder pain prevalences, such as in the general population in the Netherlands (20.9%), the general population in Sweden (19.88%) [46] and dentists in Greece (19.77%) [39]. However, our results differ from those examining different populations, which reported either higher or lower prevalence rates compared to our study, such as school teachers in Saudi Arabia (59.26%) [51], nursing assistants in Norway (47.1%) [36], the working population in New Zealand (42%) [35], occupational drivers in Nigeria (30.82%) [34], agricultural farmers in Nepal (10.57%) [40], the general population in the United Kingdom (7.48%) [52] and construction workers in Saudi Arabia (4.24%) [43].
In terms of potential risk factors, we found that shoulder pain among pilgrims was more common in females, pilgrims who were underweight (BMI: <18.5) (close to the margin of significance), those who had diabetes and hypertension, those who believed that the Hajj is physically exhausting, those who had experienced a fall during the Hajj and those who received treatment during the Hajj. These findings are similar to those of several studies that found that shoulder pain was more common in females among the general populations in Sweden [46], the United Kingdom [52] and the Netherlands [42], nursing assistants in Norway [36] and the working population in New Zealand [35]. Our findings are also similar to those indicating the presence of chronic disease, anxiety and depression [51] among female school teachers. However, our findings differ from those of a study reporting that shoulder pain was not associated with sex [39] among dentists in Greece. In our study, age was not associated with shoulder pain among pilgrims. This result is similar to those of some studies conducted among dentists in Greece [39] and the general population in the Netherlands [42]. In contrast, some studies found that age was associated with shoulder pain among the general population in the United Kingdom [52] and nursing assistants in Norway [36], where older individuals were at a higher risk than younger individuals. In our study, the prevalence of falls was associated with shoulder pain. This differs from the results of a study conducted among the older population in the United States, which found no association between falls and shoulder pain [45].
Musculoskeletal pain of the lower limb
In our study, the most common location of musculoskeletal pain in the lower limbs among pilgrims was ankle/foot pain (39.07%), which was higher than the prevalence identified in most studies in the literature. Few studies reported higher rates of ankle/foot pain, such as a study conducted among school teachers in Saudi Arabia (ankle: 42.59%, heel: 55.97%) [51]. Most studies reported lower rates of ankle/foot pain compared to our study, such as a study of the working population in New Zealand (20%) [35], nursing assistants in Norway (15.5%) [36], agricultural farmers in Nepal (13.01%) [40], the general population in Sweden (12.37%), occupational drivers in Nigeria (11.95%) [34], the general population in the Netherlands (ankle: 4.9%, foot: 6.5%) [42] and construction workers in Saudi Arabia (3.03%) [43].
In terms of potential risk factors, we found that ankle/foot pain among pilgrims was more common in females, those who had diabetes, those who believed that the Hajj was physically exhausting and those who received treatment during the Hajj. Our results were similar to those of Alfelali et al. (2014), who reported that pilgrims with or without diabetes were at a high risk of developing foot injuries during the Hajj [27], but this study was focused on infectious wounds in the foot. Some studies had similar findings and reported that ankle/foot pain was more common females among the general population in Sweden [46] and in the Netherlands [42]. In our study, although there were significant age-based differences in hip/pelvis, knee and leg pain, there was no difference in ankle/foot pain between younger and older individuals. This result differs from that of some studies reporting that ankle or foot pain was more common in older individuals than in younger individuals among the general population in the Netherlands [42] and nursing assistants in Norway [36].
We did not find an association between BMI and ankle/foot pain. This differs from the results of one study, which reported that heel pain was associated with BMI, although this study did not find similar results for ankle pain [51]. Our findings are also similar to those of studies that found an association between the presence of chronic disease, anxiety and depression [51] among female school teachers and ankle and heel pain. In our study, the prevalence of falls was not associated with higher rates of ankle/foot pain. This is similar to the results of a study conducted among the older population in the United States, which found no association between falls and foot pain [45].
Possible explanations for the differences in the results of musculoskeletal pain between our study and others in the literature
The variations in the results for estimating the prevalence of musculoskeletal pain between our study and others in the literature can be possibly explained by several factors, including the differences in populations, study design and methodology, such as the large variation in the sample size, data collection method and statistical analysis. For example, some studies estimated the point prevalence of musculoskeletal pain [38, 41, 43, 46, 51, 52], whereas others estimated period prevalence [35, 37, 44, 45] or both [40, 42, 49]. Many studies had a small or an average sample size (< 400) [34, 37, 38, 40, 41, 43]. Other studies only estimated the prevalence of chronic cases of musculoskeletal conditions [45–48, 50]. Several studies either limited the data collection to specific regions within the country [38, 43, 44, 46, 52, 53] or to only males [43] or only females [51]. Others included a limited range of age groups (20–29, 30–39, ≥ 40) [51], did not consider participants from the elderly population (< 65) [34, 35, 40, 53] or only included older participants (≥ 70) [45]. This may have influenced the distribution of the data, making it difficult to detect the differences between the younger and elderly populations. Furthermore, some studies did not control for potential confounding variables (e.g., age) [43, 51], which may have led to inaccurate associations. Other studies only focused on particular anatomical sites of pain [52] or included more than one anatomical site of pain as a region, for example, by combining the neck, shoulder and higher back sites into one region [42], by combining all sites of pain for the upper limb or the lower limb [44], combining the hip with the upper leg, combining the lower leg with the foot [46] or combining the hip, thigh and buttock [35]. All of these variations may have impacted the estimation of musculoskeletal pain prevalence.
There are possible explanations for why our study showed a higher prevalence of musculoskeletal pain among pilgrims. One possible explanation is that the Hajj is highly physically demanding; pilgrims move, generally by foot, for long distances, which may exceed the typical physical activity level for most pilgrims and is further complicated by overcrowding, extreme heat and fatigue [11, 13, 15, 21]. Several studies have documented an association between some jobs or tasks with high physical demands and musculoskeletal pain among different populations [37, 46]. For example, individuals who primarily work while standing and for longer periods of time [44, 51], individuals who often or always lift heavy loads [44] and individuals exposed to high physical workloads [35] display an increased risk of musculoskeletal pain, particularly in the lower limb [35, 44]. Other possible explanations are that the normal life routines of individuals may change as they move between places where the geography and climate are different, or individuals may neglect their self-health management while they are preoccupied with religious rituals [11]. Subsequently, pilgrims are at a higher risk for developing musculoskeletal pain.
Study strengths and limitations
To the best of our knowledge, this is the first study that has investigated the prevalence of musculoskeletal pain and associated risk factors among pilgrims. One strength of this study is that the power calculation was performed, and the required sample size was achieved, leading to a large sample with the power to detect significant results where they existed. The data were mainly collected by trusted healthcare professional volunteers who approached individuals at different sites of Mecca during the Hajj. The completion rate of the survey in this study was considerably acceptable (1,715/2,110; 81.28%). Another strength is that all data were collected in a short period (10 days) during the Hajj only to properly estimate the point prevalence of musculoskeletal pain among pilgrims. Another strength is the investigation of the association between musculoskeletal pain and various potential risk factors with the consideration of potential confounding factors by using an adjusted OR ratio that controls for sex and age within the regression model used in this study.
There were some limitations to the current study. First, there was a potential sampling bias due to the use of convenience sampling, which may have produced a sample that is not representative of the entire pilgrim population that visited Mecca to perform the Hajj. However, an attempt was made to reduce the sampling bias by distributing the survey at different sites in Mecca during the Hajj and by collecting data from pilgrims regardless of their nationality. This study also used a cross-sectional design, which is limited to demonstrating a causal association. Another limitation is the fact that 18.72% of the participating pilgrims only provided demographic and major medical history information, without any information related to musculoskeletal pain, which was possibly due to time limitations or a refusal to answer all the follow-up questions; therefore, these responses were excluded from the analysis. Furthermore, due to the way the survey was distributed in this study, and due to the use of convenience sampling, it was impossible to estimate the response rate.