Abstract
Background
The global prevalence of shoulder pain varies widely across countries. Additionally, shoulder pain and frozen shoulder can significantly affect patients' quality of life due to high levels of pain and disability.
Objective
This study aimed to investigate the prevalence of shoulder pain and its risk factors. It also aims to assess the level of knowledge regarding frozen shoulders and its related factors in Taif City, Saudi Arabia.
Methods
A cross-sectional observational study was conducted in Taif City in December 2023 using a validated questionnaire comprised of socio-demographic characteristics, the prevalence of shoulder pain, and the awareness of frozen shoulders.
Results
A total of 378 participants enrolled in the study, with 54.8% being male and 62.7% being graduates and having jobs equally distributed among office (24.9%) and in the field (24.9%). Most participants were smokers (75.9%) and did not engage in body-building activities (79.6%). Around 26.5% of them had diabetes. The prevalence of shoulder pain was 32.8%. Aging from 35 to 44 years (p<0.001), having a higher salary from 6000 to 10000 SAR (p<0.001), retirement (p<0.001), engaging in body-building activities (p=0.035), having diabetes (p<0.001), and having other comorbidities (p<0.001) are significantly impacted having shoulder pain. Increased knowledge about the frozen shoulder is correlated with aging from 25-34 (p=0.026), smoking (p=0.002), engaging in bodybuilding (p<0.001), having diabetes (p=0.010), and having other medical conditions (p=0.010).
Conclusion
The study has shown that shoulder pain is prevalent among Taif City's population. Nevertheless, a low level of knowledge was observed. Therefore, enhancing the national educational programs is needed to increase public awareness of frozen shoulders.
Keywords: taif, saudi arabia, awareness, prevalence, frozen shoulder, shoulder pain
Introduction
Shoulder pain is a common problem worldwide that is prevalent among approximately 16% of the general population [1]. Frozen shoulder, also known as adhesive capsulitis, is a condition that causes pain and stiffness in the shoulder joint. It is characterized by severe pain and inability to move the shoulder. Frozen shoulders develop in three stages: freezing, frozen, and thawing. The condition usually improves within 12 to 18 months, but severe or persistent symptoms may require treatment [2].
The global prevalence and incidence of shoulder pain vary widely across countries. It is reported to be the third most common musculoskeletal symptom presenting for health care and makes up an estimated 4% of annual consultations by adults in UK primary care [3]. The prevalence of frozen shoulder is estimated to be between 2% and 5% of the general population globally [4]. Most patients are between 40 and 60 years old at diagnosis. However, some evidence suggests that frozen shoulders can occur later in life. Risk factors for developing frozen shoulders include diabetes, thyroid problems, hormone changes, shoulder injury, shoulder surgery, open heart surgery, and cervical disk disease of the neck [5].
In Saudi Arabia, the condition has been prominent in several areas. A study conducted in the Western region of Saudi Arabia discovered that the prevalence of frozen shoulders among diabetic patients was 31.6% [6]. Another retrospective study conducted in the Qassim region discovered that the prevalence rate of frozen shoulders was 13.2% [7].
Shoulder pain and frozen shoulders can have a significant impact on patients' quality of life as they may experience high rates of pain and disability compared to the general population [8]. Complications that may arise include residual shoulder pain and stiffness, humeral fracture, rupture of the biceps and subscapularis tendons, and labral tears [9]. The long-term effects of frozen shoulders vary depending on the individual and the severity of the condition, which may affect all facets of life, including work impact, sleep, personal hygiene, interpersonal relationships, and independence [10].
There is not enough recent or updated data about the condition's prevalence among the general population in Saudi Arabia and Taif City. Therefore, this study aimed to assess the prevalence of shoulder pain and its associated factors. Furthermore, it aims to discuss the knowledge level and its correlated factors with frozen shoulders awareness among the general population in Taif City, Saudi Arabia.
Materials and methods
Study design and duration
A cross-sectional observational study was performed among the general population in Taif City, Saudi Arabia. The data was collected in December 2023.
Study population
The study included a general population of 16 years or older living in Taif City who are willing to participate in the study.
Sampling technique
A simple random sampling technique was used in this study to select the participants
Sample size calculation
The Raosoft sample size calculator (2004, Raosoft, Inc., Seattle) was used online to calculate the sample size. Based on a confidence level of 95%, a margin of error of 5%, and a maximum uncertainty of 50% for positive responses, a minimum of 377 participants should be included in this study.
Data collection method
Data was collected through a structured and self-administered electronic questionnaire distributed to adults in Taif City as a link to Google form using social media platforms (e.g., Twitter, Instagram, Linked-in, WhatsApp, etc.).
Data collection tool
The data collection tool was a structured questionnaire designed based on a previous study entitled "The Prevalence of Shoulder Pain and Awareness of Frozen Shoulder Among the General Population in Assir Region" [6]. The questionnaire was validated in the Assir Region in Saudi Arabia, and it included three sections: the first section comprised participants' characteristics, the second section focused on the habits and diseases of the participants, and the third section addressed knowledge about frozen shoulder. The demographics included age, gender, educational status, working style, and income. Habits and diseases included questions about smoking status, diabetes and comorbidities, and exercise activity. Knowledge about frozen shoulder included questions related to age groups, disease signs and symptoms, gender, risk factors, anxiety, and depression.
Pilot study
The questionnaire was administered to 10 respondents to ensure that it was easily understood and to estimate the time needed to fill it out. Data collected in the pilot study were not included in the statistical analysis.
Data entry and analysis
The data was extracted and revised in an Excel sheet. Statistical analysis was conducted using the SPSS (IBM Corp. Released 2019. IBM SPSS Statistics for Windows, Version 26.0. Armonk, NY: IBM Corp). Categorical variables were expressed in numbers and percentages, while continuous variables were checked for normality. The Chi-square test was used to compare different variables with shoulder pain and awareness of frozen shoulders. The statistical significance was established by considering p-values below 0.05.
Ethical considerations
Approval was given by the Research and Ethics Committee of Armed Forces Hospitals, with the application number 2023-822.
Results
The study included 378 participants, with about half (185, 48.9%) aged 45 or older (207, 54.8%) male. The majority were graduates (237, 62.7%). Approximately half of them had an income of more than 10,000 Saudi Riyal (SAR) per month(186, 49.2%). About a quarter of the participants were unemployed (94, 24.9%), worked in office-based jobs (94, 24.9%), and worked in field-based jobs (94, 24.9%). Full details are shown in Table 1.
Table 1. Demographic characteristics of the participants (N=378).
Parameters | Category | Number (N) | Percentage (%) |
Age (Years) | 16-24 | 54 | 14.3 |
25-34 | 56 | 14.8 | |
35-44 | 83 | 22.0 | |
More than or equal to 45 | 185 | 48.9 | |
Gender | Male | 207 | 54.8 |
Female | 171 | 45.2 | |
Income (SAR) | Less than 6000 | 94 | 24.9 |
From 6000 to 10000 | 98 | 25.9 | |
More than 10000 | 186 | 49.2 | |
Educational level | Uneducated | 9 | 2.4 |
High school student | 77 | 20.4 | |
College student | 55 | 14.6 | |
Graduated | 237 | 62.7 | |
Working style (N=377) | Unemployed | 94 | 24.9 |
Lawyer | 1 | 0.3 | |
Teacher | 6 | 1.6 | |
Field-based | 94 | 24.9 | |
Office-based | 94 | 24.9 | |
Pharmacist | 1 | 0.3 | |
Military | 2 | 0.5 | |
Private sector | 1 | 0.3 | |
School agent | 2 | 0.5 | |
Retired | 82 | 21.7 |
Regarding respondents' habits and disease, most participants were smokers (287, 75.9%) and did not practice bodybuilding (301, 79.6%). About a quarter of them had diabetes (100, 26.5%), with 80 patients (80%) having type II diabetes, and 33 cases (33%) had diabetes for more than ten years. More details are presented in Table 2.
Table 2. Habits and diseases of the participants (N=378).
Parameters | Category | Number (N) | Percentage (%) |
Smoking | Yes | 287 | 75.9 |
No | 91 | 24.1 | |
Practicing bodybuilding | Yes | 77 | 20.4 |
No | 301 | 79.6 | |
Having diabetes | Yes | 100 | 26.5 |
No | 278 | 73.5 | |
Type of diabetes (N=100) | Type I | 20 | 20 |
Type II | 80 | 80 | |
Duration of having diabetes (N=100) | Less than one year | 6 | 6 |
From 1 to 5 years | 30 | 30 | |
From 5 to 10 years | 31 | 31 | |
More than 10 years | 33 | 33 | |
Having other comorbidities | Yes | 128 | 34 |
No | 250 | 66 | |
If yes, please specify (N=128) | Hypertension | 41 | 32.0 |
Joint diseases | 35 | 27.3 | |
Glands disorder | 25 | 19.5 | |
Kidney diseases | 13 | 10.2 | |
Heart diseases | 13 | 10.2 | |
Psychiatric illness | 8 | 6.3 | |
Asthma | 3 | 2.3 | |
Anemia | 3 | 2.3 | |
Problems in vertebras | 2 | 1.6 | |
Others | 6 | 4.7 |
As illustrated in Figure 1, the prevalence of shoulder pain in Taif City was (124, 32.8%).
Table 3 illustrates the participants' knowledge about frozen shoulder. Most of them did not know frozen shoulders (321, 84.9%). More than half of the participants reported that individuals aged between 40 and 60 are the most affected by the frozen shoulder (208, 55%); also, (217, 57.4%) reported all the signs and symptoms of a frozen shoulder. Also, the most reported risk factors for a frozen shoulder were immobilization for the long term (182, 48.1%), followed by diabetes mellitus and shoulder trauma (155, 41%). Finally, anxiety (167, 44.2%) and depression (134, 35.4%) were reported to increase the risk of a frozen shoulder.
Table 3. Respondents' knowledge about frozen shoulder.
Factors | Categories | Number (N) | Percentage (%) |
knowledge about frozen shoulder | Yes | 57 | 15.1 |
No | 321 | 84.9 | |
Age groups that are most commonly affected by frozen shoulder | Less than 20 years | 15 | 4 |
20 – 40 years | 72 | 19 | |
40 – 60 years | 208 | 55 | |
More than 60 years | 83 | 22 | |
Signs and symptoms of a frozen shoulder | Shoulder pain | 111 | 29.4 |
The shoulder's range of motion starts decreasing | 67 | 17.7 | |
Stiffness | 35 | 9.3 | |
Shoulder swelling | 20 | 5.3 | |
All | 217 | 57.4 | |
Gender is more likely to be affected by a frozen shoulder | Male | 188 | 49.7 |
Female | 190 | 50.3 | |
Risk factors for a frozen shoulder | Immobilization for long-term | 182 | 48.1 |
Diabetes mellitus | 155 | 41 | |
Shoulder trauma | 155 | 41 | |
Thyroid disease | 65 | 17.2 | |
Hyperlipidemia | 44 | 11.6 | |
Autoimmune diseases | 38 | 10.1 | |
Depression increases the risk of getting a frozen shoulder | Yes | 134 | 35.4 |
No | 244 | 64.6 | |
Anxiety increases the risk of getting a frozen shoulder | Yes | 167 | 44.2 |
No | 211 | 55.8 |
Factors correlated with shoulder pain were assessed in Table 4. Shoulder pain has a significant correlation with age (p<0.001), income (p<0.001), and working style (p<0.001) of the participants. A higher prevalence of shoulder pain was observed in participants aged 35 to 44 years, with income from 6000 to 10000 SAR, and retired participants. However, the gender and education level of the participants showed no significant correlation with shoulder pain.
Table 4. Correlation between the shoulder pain and respondents' characteristics:
Factors | Shoulder pain N (%) | p-value | ||
Yes | No | |||
Age (Years) | 16-24 | 4 (7.4) | 50 (92.6) | <0.001 |
25-34 | 18 (32.1) | 38 (67.9) | ||
35-44 | 35 (42.2) | 48 (57.8) | ||
More than or equal to 45 | 67 (36.2) | 118 (63.8) | ||
Gender | Male | 63 (30.4) | 144 (69.6) | 0.280 |
Female | 61 (35.7) | 110 (64.3) | ||
Income (SAR) | Less than 6000 | 17 (18.1) | 77 (81.9) | <0.001 |
From 6000 to 10000 | 45 (45.9) | 53 (54.1) | ||
More than 10000 | 62 (33.3) | 124 (66.7) | ||
Educational level | Uneducated | 5 (55.6) | 4 (44.4) | 0.469 |
High school student | 23 (29.9) | 54 (70.1) | ||
College student | 17 (30.9) | 38 (69.1) | ||
Graduated | 79 (33.3) | 158 (66.7) | ||
Working style | Unemployed | 19 (20.2) | 75 (79.8) | <0.001 |
Office-based | 36 (34.3) | 69 (65.7) | ||
Field-based | 27 (28.1) | 69 (71.9) | ||
Retired | 42 (51.2) | 40 (48.8) |
Additionally, regarding individuals' habits and comorbidities (Table 5), practicing bodybuilding [odds ratio(OR)=1.42, p=0.035], having diabetes (OR=1.88, p<0.001), and having comorbidities (OR=2.27, p<0.001) showed a significant correlation with shoulder pain. However, smoking status showed no significant correlation with shoulder pain.
Table 5. Association between shoulder pain and the habits and diseases of the participants.
Factors | Shoulder pain N (%) | p-value | ||
Yes | No | |||
Smoking | Yes | 33 (36.3) | 58 (63.7) | 0.420 |
No | 196 (68.3) | 91 (31.7) | ||
Doing sports such as bodybuilding | Yes | 33 (42.9) | 44 (57.1) | 0.035 |
No | 91 (30.2) | 210 (69.8) | ||
Having diabetes | Yes | 50 (50) | 50 (50) | <0.001 |
No | 74 (26.6) | 204 (73.4) | ||
Having other comorbidities | Yes | 67 (51.9) | 62 (48.1) | <0.001 |
No | 57 (22.9) | 192 (77.1) |
Concerning associated factors with increased awareness of frozen shoulder (Table 6), no significant correlation was seen between the individuals' characteristics and shoulder pain except for age (P=0.026). The participants aged 25 to 34 years (13, 23.2%) had the highest knowledge about frozen shoulders.
Table 6. Correlated factors associated with knowledge about frozen shoulder.
Factors | Knowledge about frozen shoulder N (%) | p-value | ||
Yes | No | |||
Age (Years) | 16-24 | 7 (13) | 47 (87) | 0.026 |
25-34 | 13 (23.2) | 43 (76.8) | ||
35-44 | 18 (21.7) | 65 (78.3) | ||
More than or equal to 45 | 19 (10.3) | 166 (89.7) | ||
Gender | Male | 34 (16.4) | 173 (83.6) | 0.421 |
Female | 23 (13.5) | 148 (86.5) | ||
Income (SAR) | Less than 5000 | 12 (12.8) | 82 (87.2) | 0.228 |
From 6000 to 10000 | 20 (20.4) | 78 (79.6) | ||
More than 10000 | 25 (13.4) | 161 (86.6) | ||
Educational level | Uneducated | 3 (33.3) | 6 (66.7) | 0.492 |
High school student | 11 (14.3) | 66 (85.7) | ||
College student | 8 (14.5) | 47 (85.5) | ||
Graduated | 35 (14.8) | 202 (85.2) | ||
Working style | Unemployed | 17 (18.1) | 77 (81.9) | 0.815 |
Office-based | 14 (13.3) | 91 (86.7) | ||
Field-based | 14 (14.6) | 82 (85.4) | ||
Retired | 12 (14.6) | 70 (85.4) |
Regarding the impact of habits and having comorbidities on frozen shoulder knowledge (Table 7), a significant correlation between being a smoker (OR=2.14, p=0.002), practicing bodybuilding (OR=2.47, p<0.001), having diabetes (1.89, p=0.010), and having comorbidities (OR=1.87, p=0.010) with higher knowledge about frozen shoulder.
Table 7. Association between the habits and diseases of the participants and knowledge about frozen shoulder.
Factors | Knowledge about frozen shoulder N (%) | p-value | ||
Yes | No | |||
Smoking | Yes | 23 (25.3) | 68 (74.7) | 0.002 |
No | 34 (11.8) | 253 (88.2) | ||
Practicing bodybuilding | Yes | 22 (28.6) | 55 (71.4) | <0.001 |
No | 35 (11.6) | 266 (88.4) | ||
Having diabetes | Yes | 23 (23) | 77 (77) | 0.010 |
No | 34 (12.2) | 244 (87.8) | ||
Having other comorbidities | Yes | 28 (21.7) | 101 (78.3) | 0.010 |
No | 29 (11.6) | 220 (88.4) |
Discussion
This study aimed to assess the prevalence of shoulder pain and awareness of frozen shoulders among the general population in Taif City, Saudi Arabia. The prevalence of shoulder pain in Taif City was (124, 32.8%). Shoulder pain significantly correlated with age, income, working style of the participants, practicing bodybuilding, diabetes, and comorbidities. Additionally, age, smoking status, bodybuilding, diabetes, and comorbidities showed a significant correlation with knowledge about frozen shoulders.
According to our study, shoulder pain in Taif City, Saudi Arabia, was (124, 32.8%), similar to Japan's (30%) [11]. However, the prevalence in Taif City was higher than in the urban areas of Bauru [12](24%) and the urban regions of India (2%), as well as in rural areas of India (7.4%) [13]. Conversely, the prevalence in Taif City was lower than in the Netherlands [14](48%) and China [15] (48.7%). These variations in prevalence rates may be because there is no uniform definition for the clinical condition and anatomical area of the cervical and shoulder regions across different studies [12].
Our research indicated that shoulder pain is commonly experienced by individuals aged 35-44 years, 45 years or older, and those who retire (above 60 years of age). These findings are similar to studies conducted in Bauru [13] and the Netherlands [16], which also reported that shoulder pain was linked with people aged 60 years or older. However, shoulder pain was observed more frequently in Japan in young adults [16]. The increased prevalence of shoulder pain in older adults can be attributed to degenerative changes in muscles, tendons, ligaments, and joints that naturally occur with aging, chronic overload for the elderly worker, and prolonged exposure to occupational risk factors [16].
Unfortunately, (321, 84.9%) of individuals in Taif did not know frozen shoulders. However, in a previous study in Aseer in Saudi Arabia, 69.31% had sufficient knowledge about frozen shoulders [6]. Regarding the symptoms of frozen shoulders, the Aseer region study [6], reported that about half believed that multiple symptoms aligned with our study, where most participants reported all symptoms (shoulder pain, start decreasing shoulder range of motion (ROM), stiffness, and swelling). Additionally, the most reported risk factors in our study for a frozen shoulder were immobilization for the long term, diabetes mellitus, thyroid diseases, and shoulder trauma, which is per the published literature [17,18]. In our study, a low percentage agreed that anxiety and depression increase the risk of a frozen shoulder, which was in contrast to Aseer's study, which demonstrated that a much higher percentage of individuals thought that depression and anxiety could increase the chance of shoulder diseases [6].
In our study, age was a significant factor impacting the awareness about frozen shoulders in Taif City, where the participants aged from 25 to 34 years had higher knowledge. However, the Aseer region study [6]. reported that gender was a significant factor in awareness about frozen shoulders. It could return to the culture of regions in Saudi. Additionally, smoking, practicing bodybuilding, having diabetes, and other comorbidities had a higher knowledge about frozen shoulders than others. It could return to the possibility of having frozen shoulders with such factors.
Limitations
These results were obtained only from Taif City and cannot be generalized to the entire Saudi population. More extensive studies may help better understand the factors influencing the prevalence of shoulder pain and awareness about frozen shoulders in Saudi Arabia.
Conclusions
Our findings have shown widespread shoulder pain among the general population in Taif City. Certain habits and comorbidities had an impact on the prevalence of shoulder pain. Additionally, most of Taif's population had a low awareness of frozen shoulders. Therefore, it is essential to provide campaigns to increase awareness about frozen shoulders, their symptoms, habits, and diseases affecting shoulder pain.
The authors have declared that no competing interests exist.
Author Contributions
Acquisition, analysis, or interpretation of data: Mohammed H. Alfaqih , Ahmed A. Alghamdi, Eyad H. Alfaqih, Mohammed A. Alamri, Layal H. Alfaqih, Mohab S. Almadani
Drafting of the manuscript: Mohammed H. Alfaqih
Concept and design: Ahmed A. Alghamdi, Hussein H. Mufti
Critical review of the manuscript for important intellectual content: Ahmed A. Alghamdi, Eyad H. Alfaqih, Mohammed A. Alamri, Layal H. Alfaqih, Hussein H. Mufti , Mohab S. Almadani
Supervision: Ahmed A. Alghamdi
Human Ethics
Consent was obtained or waived by all participants in this study. The Research Ethics Committee of Armed Forces Hospitals issued approval 2023-822. The Research and Ethics Committee of Armed Forces Hospitals has reviewed the manuscript entitled, "The Prevalence of Shoulder Pain and Awareness of Frozen Shoulder among the General Population in Taif City, Saudi Arabia" with the application number (2023-822), and approved the project under the expedited/ normal procedure.
Animal Ethics
Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue.
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