Nigerian Journal of Clinical Practice

ORIGINAL ARTICLE
Year
: 2021  |  Volume : 24  |  Issue : 11  |  Page : 1573--1581

Prevalence and risk factors associated with musculoskeletal disorders among pregnant women in Enugu Nigeria


NO Onyemaechi1, CO Chigbu2, EO Ugwu2, NI Omoke3, OA Lasebikan4, BC Ozumba2,  
1 Department of Surgery, College of Medicine, University of Nigeria, Ituku-Ozalla, Enugu, Nigeria
2 Department of Obstetrics and Gynaecology, College of Medicine, University of Nigeria, Ituku-Ozalla, Enugu, Nigeria
3 Department of Surgery, Ebonyi State University/Federal Teaching Hospital Abakaliki, Nigeria
4 Department of Orthopaedic Surgery, National Orthopaedic Hospital Enugu, Nigeria

Correspondence Address:
Dr. N O Onyemaechi
Department of Surgery, College of Medicine, University of Nigeria, Ituku-Ozalla, Enugu
Nigeria

Abstract

Background: Pregnancy usually triggers a wide range of changes that result in a variety of musculoskeletal disorders (MSDs). The scope and burden of these disorders in Nigeria are not known. Aim: The study aimed to determine the prevalence and risk factors of pregnancy-related MSDs in Enugu. Patients and Methods: A cross-sectional study of pregnant women attending antenatal clinics at three tertiary hospitals in Enugu, Nigeria, was done using an observer-administered questionnaire. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 22. Results: A total of 317 participants were studied. A majority of the participants (93.1%) had one or more MSDs. Low back pain (LBP) and muscle cramps were the two most common pregnancy-related MSDs with prevalence rates of 56.8 and 54.8%, respectively. Increasing gestational age (P = 0.001), previous pregnancies (P = 0.027), and occupation (P = 0.018) were associated with increased risk of MSDs. A majority of the MSDs were of mild and moderate severity and 10.4% of the participants had significant impairment of their daily activities. Conclusion: MSDs are common in pregnancy with LBP and muscle cramps as the most prevalent conditions. Increasing gestational age, multigravidity, and occupation increased the risk of MSDs among our cohorts. Preventive and therapeutic measures should be instituted when necessary to ensure optimal maternal health during pregnancy.



How to cite this article:
Onyemaechi N O, Chigbu C O, Ugwu E O, Omoke N I, Lasebikan O A, Ozumba B C. Prevalence and risk factors associated with musculoskeletal disorders among pregnant women in Enugu Nigeria.Niger J Clin Pract 2021;24:1573-1581


How to cite this URL:
Onyemaechi N O, Chigbu C O, Ugwu E O, Omoke N I, Lasebikan O A, Ozumba B C. Prevalence and risk factors associated with musculoskeletal disorders among pregnant women in Enugu Nigeria. Niger J Clin Pract [serial online] 2021 [cited 2021 Nov 28 ];24:1573-1581
Available from: https://www.njcponline.com/text.asp?2021/24/11/1573/330469


Full Text



 Introduction



During pregnancy, many hormonal and anatomical changes occur that affect the musculoskeletal system in women. These changes may cause various musculoskeletal problems that may alter the course of the preexisting conditions or predispose to injury.[1],[2] Biomechanical factors such as postural changes (lumbar hyperextension) play a major role and together with hormonal changes produce musculoskeletal symptoms in pregnancy.[3] Mechanical stress on the axial skeleton and pelvic girdle associated with pregnancy may lead to painful and neurologic disorders and other musculoskeletal conditions.

A majority of pregnant women experience some degree of musculoskeletal pain during pregnancy and at least 25% have temporarily disabling symptoms.[4] The common musculoskeletal disorders (MSDs) during pregnancy include low back pain (LBP), carpal tunnel syndrome (CTS), De Quervain's tenosynovitis, pelvic girdle pain (PGP), muscle cramps, joint pains, varicose veins, and urinary stress incontinence.[1],[5] MSDs could be influenced by some factors such as level of activity, gestational age, cultural influences, and environmental factors.[5]

LBP is one of the most common MSDs associated with pregnancy.[6],[7],[8] An estimated 50–90% of the women will experience some type of back pain during their pregnancies, making this experience so common that it has been accepted as an almost inevitable problem in pregnancy.[6],[7],[8],[9] About 50–55% of women worldwide are affected by lower limb varicose veins during pregnancy which is more common in multigravida and is either reversible or decreases or is after delivery.[10] Muscle cramping is another common musculoskeletal complaint that occurs during the second half of pregnancy in 15–30% of women.[1] Albert et al.[11] in a prospective epidemiologic cohort study reported a prevalence of 20.1% among pregnant Danish women. The pelvic girdle syndrome was 6%, symphysiolysis 2.3%, one-sided sacroiliac syndrome 5.5%, and double-sided sacroiliac syndrome 6.3%.[11]

MSDs can have a significant impact on the quality of life during pregnancy and may be of variable duration and intensity. There are limited guidelines for the diagnosis and management of MSDs during pregnancy.[12],[13] This may be attributable to the belief by many healthcare providers that these conditions are normal in pregnancy and pose no serious health risk to the mother or fetus.[12],[13] There is evidence that MSDs have both biomechanical and psychosocial consequences which may influence the quality of life of pregnant mothers.[5],[14],[15] Providers of antenatal care should be able to recognize these MSDs and institute prompt preventive and therapeutic measures. The prevalence and severity of pregnancy-related MSDs vary among different populations.[16] There is a paucity of data on the prevalence and risk factors of pregnancy-related MSDs in Enugu, southeast Nigeria. Consequently, the burden and scope of this problem in our environment are not known. The aim of the study is to describe the scope and pattern of pregnancy-related MSDs and the associated risk factors in our setting.

 Methods



Study design and setting

This was a cross-sectional study of pregnant women receiving antenatal care at three tertiary health facilities in the Enugu State, southeastern Nigeria, from June to December 2017. The health facilities were the University of Nigeria teaching hospital, Ituku-Ozalla, Enugu, Military Hospital Enugu, and Ntasi-Obi specialist hospital Trans-Ekulu Enugu.

The University of Nigeria teaching hospital serves a mix of urban and rural populations and also serves as a referral center for the southeastern Nigerian states of Enugu, Imo, Anambra, Abia, Ebonyi as well as Benue state in north-central Nigeria. The Military Hospital, Enugu and Ntasi-Obi specialist hospital Trans-Ekulu Enugu are tertiary hospitals in the Enugu metropolis and serve a mix of low and middle socioeconomic populations. These three hospitals provide antenatal care to a majority of pregnant women in Enugu.

Study population and sampling

The study population comprised pregnant women who attended antenatal clinics (ANC) at the study sites within the study period. The participants recruited for the study were pregnant women between the ages of 18 and 45 years. The participants needed to be up to 18 years to ensure skeletal maturity while participants older than 45 years were excluded to eliminate degenerative MSDs associated with aging. Other exclusion criteria were the presence of any MSD before the onset of pregnancy; the presence of any musculoskeletal deformities of the joints, limbs, or spine prior to pregnancy; history of traumatic injury to the musculoskeletal system 1 year before the pregnancy and refusal to give informed consent.

The sample size was calculated using the Krejcie and Morgan sample size estimation formula (1970)[17] and was approximated at 317. Using stratified random sampling, recruitment of participants from each study site was done in proportion to the population of antenatal attendees at each site. One hundred and sixty-seven participants were recruited from the University of Nigeria teaching hospital; 58 from the Military hospital, Enugu, and 92 from the Ntasi-Obi Specialist Hospital Trans-Ekulu Enugu.

Data collection

A 19-item observer-administered structured questionnaire was used for data collection. The content was validated by two experts from the field of orthopedic surgery and obstetrics and gynecology. The questionnaire was pretested on 10 pregnant women in various trimesters for comprehensiveness and content validity, and the final version was developed after corrections. Informed consent was obtained from each participant before recruitment. The questionnaire was used to obtain data on demographics, gestational age, body mass index (BMI), parity, specific MSDs, onset and severity of the MSDs, the impact of the MSDs on daily activities, and presence of any comorbidities. The severity of pain and discomfort was assessed using a self-reported four-point Likert scale (1 = no pain; 2 = mild; 3 = moderate; and 4 = severe). For urinary incontinence, the severity was assessed using the frequency of urine leak: 1–4 times a month = mild; 1–6 times a week = moderate; once a day = severe; more than once a day = very severe.[18]

Data analysis

The data from the completed questionnaires were entered into the Statistical Package for the Social Sciences (SPSS) version 22 for analysis. Descriptive statistics were employed to summarize data and were expressed as means, standard deviations (SDs), frequencies, and percentages. Inferential statistics were employed to test for associations between variables. Chi-square tests were used to test for associations between the categorical variables. The variables that had significant associations were subjected to multiple logistic regression analysis to test the strength of association between the MSDs and demographic characteristics. The P value of less than 0.05 was considered statistically significant.

Ethics approval: Ethical clearance was obtained from the Research and Ethics Committee of the University of Nigeria Teaching Hospital Ituku-Ozalla Enugu, Nigeria.

 Results



A total of 317 pregnant women were studied. Their ages ranged from 18 to 42 years with a mean age of 29.6 SD 5.4 years. The mean gestational age of the participants was 27.2 SD 6.9 weeks with a range of 12–40 weeks. The majority, 127 (40.1%), of the participants were overweight, 96 (30.3%) had normal weight, 2 (0.6%) were underweight while 92 (29%) were obese. More than half of the participants 179 (56.6%) received tertiary education; 115 (36.3%) received at least secondary education; 9 (2.8%) had only primary education, while 14 (4.4%) received no formal education [Table 1]. The prevalence of multiple pregnancies among the participants was (27) 8.5%. Only 88 (27.8%) participants were primigravida mothers, 218 (68.8%) were multigravida while 11 (3.5%) were grand multigravida.{Table 1}

A majority of the participants (93.1%) had one or more MSDs, only 6.9% had no MSD. LBP and muscle cramps were the most prevalent MSDs with prevalence rates of 56.8 and 54.8%, respectively. The least prevalent MSDs were CTS (23%) and urinary incontinence (24%) [Table 2]. About 32.4% of participants had both LBP and PGP. A majority of the subjects were in their 3rd trimester of pregnancy [Table 2]. Joint pain was reported in the following joints: hip 101 (66.9%); knee 27 (17.9%); wrist 17 (11.3%); ankle 3 (2.0%) and shoulder 3 (2.0%). The dominant hand was involved in 91% of the participants with De Quervain's tenosynovitis and was bilateral in 12% of the participants. The CTS was noted to affect the dominant hand in 65% of the participants and bilateral in 32%. Leg varicose veins were reported in 29% of the participants; 32.1% of whom had varicose veins in previous pregnancies. The condition was asymptomatic in 78.4% of the participants and aggravated in 45.3% of all the participants who had leg varicose veins in previous pregnancies. Stress urinary incontinence was the commonest type of urinary incontinence (14.8%), followed by urge incontinence (6.5%), and mixed type (2.9%).{Table 2}

Age (P = 0.770); overweight and obesity (P = 0.173); and parity (0.078) did not affect the prevalence of leg varicose veins among the participants. Increasing maternal age was associated with joint pains (P = 0.027) and LBP (P = 0.008). There was also a significant association between the occupation of the participants and the prevalence of LBP, muscle cramps, PGP, De Quervain's tenosynovitis, varicose veins, and urinary incontinence. The proportion of farmers who had muscle cramps (P = 0.007); LBP (P = 0.03); De Quervain's tenosynovitis (P = 0.04); varicose veins (P = 0.009), and PGP (P = 0.034) was higher than the other occupations. There was also a significant association between sedentary workers such as tailors and bankers and the incidence of urinary incontinence (P = 0.02). Increasing gestational age was associated with the incidence of joint pains, LBP, PGP, varicose veins, and urinary incontinence.

The incidence of PGP and De Quervain's tenosynovitis was significantly associated with multigravidity (P = 0.02). There was also a strong correlation between overweight and obesity, and the incidence of LBP among the participants (P = 0.03). Increased BMI was, however, not associated with the occurrence of joint pains, muscle cramps, PGP, varicose veins, or CTS. Multiple pregnancies, the presence of comorbidities, and the level of education of participants did not influence the prevalence of any MSDs. Increasing gestational age (3rd trimester) was a risk factor for developing joint pains (hip and knees), urinary incontinence, varicose veins, and LBP. Also, the risk of developing PGP and De Quervain's tenosynovitis was significant in the participants who had more than three previous pregnancies [Table 3]. The regression analysis of all the MSDs showed that participants in their 3rd trimester were mostly at risk of developing MSDs with an odds ratio of 5.52 (P = 0.001). The occupation of the participants was also a risk factor for MSDs (OR = 1.28, P = 0.018). In addition, participants who had three previous pregnancies had an increased risk of MSDs (OR = 1.68, P = 0.027).{Table 3}

A majority of the participants had either mild or moderate conditions [Table 4]. The most severe MSDs were urinary incontinence, joint pains, and LBP; while CTS was the least severe condition. Between 2.7 and 9.9% of the participants had severe pain or discomfort while only 0–3.9% had very severe pain. The activities of daily living (ADL) were significantly affected in 10.4% of the participants.{Table 4}

 Discussion



Low back pain

LBP (56.8%) was the most prevalent MSD in this study. LBP has been reported to be the most prevalent pregnancy-related MSD with a mean prevalence rate of greater than 50% in many studies.[7],[9],[19] The pathophysiology of LBP in pregnancy appears to be a combination of factors such as hormonal, biomechanical, and impaired motor control. We noted that increasing gestational age was associated with an increased risk of LBP. As the fetus grows, the enlarging uterus causes a shift in the maternal center of gravity anteriorly. There is also increased lumbar lordosis which further increases stress on the lower back that increases the risk of developing LBP. Relaxin in pregnancy has been associated with pelvic ligamentous laxity which contributes to the increased prevalence of LBP.[20] In this study, the active participants had a higher incidence of LBP. This is in consonance with other studies that have also reported that patients who have physically demanding occupations have a higher risk of developing LBP during pregnancy.[21]

We also observed that LBP was associated with increased maternal age. The reason for this is not clear but may be related to the increased risk of degenerative lumbar spine diseases associated with increasing age.

Overweight and obese participants had a higher incidence of LBP. Previous studies have reported increased mechanical loading of the lumbar spine with consequent biomechanical changes that result in an increased incidence of mechanical LBP in pregnant women and obese and overweight participants.[22],[23] MSDs such as LBP may occur both in pregnancy and non-pregnant states. A thorough diagnostic workup is therefore important to identify other non-pregnancy-related causes such as sub-clinical rheumatic disease. The etiology of MSDs in pregnancy should not be restricted to pregnancy-related changes in the musculoskeletal system.[24]

Muscle cramps

The prevalence of muscle cramps was 54.8%. This is similar to the prevalence of 54.7% reported by Sohrabvand et al.,[25] however, it was lower than the prevalence of 65.8% reported in an Indian study.[5] Ireland et al.[1] reported a much lower prevalence of 15–30% in the second half of pregnancy. We observed that the muscle cramps occurred more in the calf than the high muscles. This is similar to the report by Ramachandra et al.[5]

Farmers and tailors were noted to have a higher incidence of calf muscle cramps. Fatigue of the calf muscle which occurs in these occupational groups may explain the higher prevalence among these groups of workers.

The prevalence was also higher in participants in their 3rd trimesters. The imbalance between the absorption and elimination of serum electrolytes such as magnesium seen with increasing gestational age which causes changes in the activities of motor neurons may explain this observation.[25],[26] In addition, dehydration may also be responsible for muscle cramps in the 3rd trimester.[27] Maternal age, parity, and BMI of the participants did not affect the prevalence of muscle cramps among the participants.

Joint pains (Arthralgia)

The prevalence of arthralgia in our study is comparable to the report by Ramachandra et al.[5] who reported a prevalence of 50.5%. Only the lower limb joints were involved and the knee joint (20.1%) was more prevalent than the ankle (14.6%) and hip joints (9.9%). The risk of joint pains increased significantly with gestational age. Previous studies have reported an increased weakness of muscles, weaker proprioception, and laxity of the ligaments as pregnancy progresses.[25],[28]

We also noted that the prevalence of arthralgia in pregnancy was associated with increasing maternal age. This may be explained by the increased risk of degenerative joints diseases associated with increasing age. In contrast to some studies, overweight and obesity were not modifiable risk factors for arthralgia among pregnant women in this study.

Pelvic girdle pain

The prevalence of PGP was 47.9% and was most commonly reported in the 3rd trimester. This is similar to reports from other studies with a prevalence rate of 45%.[29]

PGP may coexist with LBP in pregnancy and the prevalence of both MSDs may range from 4 to 90%.[29],[30] In our study, 32.4% of our participants had both LBP and PGP. Multiparity increased the risk of PGP among our participants. Several risk factors for PGP have been reported, including genetic predisposition, pelvic trauma, multiparity, increased BMI, abnormal pelvic girdle biomechanics, strenuous work, and excessive abduction.[11],[30],[31],[32]

A majority of our participants developed PGP in their 3rd trimester of pregnancy. Symphysis pubic dysfunction (SPD) was more common than sacroiliac syndrome. This pattern of PGP has also been reported by other authors.[25],[33]

Increased pelvic ligament laxity associated with multiparity and increased gestational age may result in changes in the biomechanics of the pelvic girdle that cause PGP. Strenuous activities by farmers, and hip abduction which is a common working posture for tailors, may explain the increased risk in these occupational groups.

De Quervain's tenosynovitis

The most prevalent hand disorders in pregnancy are De Quervain's tenosynovitis and CTS.[34] The prevalence of De Quervain's tenosynovitis in this study was 30% with an increased risk among the participants with previous pregnancies. The reason for this is not clear, however, a higher prevalence of the disease has been reported during the second and 3rd trimesters, and during lactation which has been attributed to fluid retention associated with hormonal changes in pregnancy and lactation.[4],[34]

In this study, the proportion of farmers and multiparous women who developed De Quervain's tenosynovitis was significantly higher than in the other groups with the dominant hand being predominantly affected. The hormonal etiology and mechanical factors such as repetitive microtrauma and local acute trauma may explain these observations.

Carpal tunnel syndrome

CTS is a common cause of hand pain in pregnancy which is most frequently diagnosed during the 3rd trimester. The prevalence of CTS in our study was 23% and was predominantly diagnosed in the 3rd trimester. A recent systematic review of CTS in pregnancy found that the incidence of CTS using electrophysiological studies was 7–43% while the incidence of clinically diagnosed CTS was 31–62%.[35] Thirty-two (10.1%) participants had both De Quervain's tenosynovitis and CTS. This may be explained by the common hormonal etiology which results in fluid retention in pregnancy and causes entrapment of the median nerve between the carpal bones and overlying transverse carpal ligament.[4],[34],[36]

The dominant hand was more commonly affected probably due to associated mechanical factors resulting from the frequent use of the hand. Age, parity, occupation, and BMI did not affect the prevalence of CTS in our study.

Varicose veins

The prevalence of leg varicose veins in the index pregnancy was 29%. This is comparable to 28% reported by Dindelli et al.[37] It is not clear whether pregnancy merely accelerates the onset of varicose veins in susceptible individuals or whether it is an independent risk factor. We noted an increased risk of varicose veins in participants in their 3rd trimester. Several theories have been used to explain the pathomechanism of varicose veins in pregnancy. Increased intra-abdominal pressure occurs during pregnancy and in addition to the direct pressure of the gravid uterus on the iliac veins will lead to back pressure on the distal venous system resulting in varicose veins.[37] This may explain the observation in our study where increasing gestational age was associated with a higher prevalence of varicose veins. In addition, the hormonal theory postulates that the estrogen and progesterone receptors in the saphenous veins mediate venous dilatation and valve failure in pregnancy resulting in varicose veins.[38]

Data on the risk factors for varicose veins in pregnancy are not consistent. Some authors have reported a higher prevalence of varicose veins with increasing maternal age.[37],[39] However, our study did not show any significant association between maternal age and varicose veins. In addition, this study did not reveal any association between parity and obesity, and varicose veins in contrast to the studies by Dindelli et al.[37] who reported a positive association with parity but not with obesity, and Abramson et al.[40] who noted that obesity increased the risk of varicose veins in pregnancy. The reasons for these different observations are not clear but can be elucidated by further study.

Urinary incontinence

The prevalence of urinary incontinence in this study was much lower than reports from Norway (58.1%)[41] and Spain (39.1%).[39] Findings from this study seem to support the previous studies that reported a higher prevalence of urinary incontinence in Caucasians than Blacks during pregnancy.[42],[43] The period prevalence of urinary incontinence during pregnancy in a Danish study was 19.9–24.1% and is similar to findings from our study.[44] Stress incontinence was the commonest type of urinary continence among our participants as reported earlier by Sangsawang et al.[45]

We also noted that the risk of urinary incontinence increased with gestational age. This may be explained by mechanical and hormonal factors. The increasing weight of the fetus is said to exert local pressure on the bladder reducing the bladder capacity which predisposes to stress incontinence. In addition, the urodynamic studies have demonstrated progressive loss of the posterior urethrovesical angle and detrusor instability as pregnancy progresses.[43],[45]

Whereas some studies conducted among Caucasian pregnant women reported multiparity, obesity, and maternal age as independent risk factors for urinary incontinence in pregnancy[42],[46]; our study noted that increased gestational age and sedentary work were strongly associated with incontinence among our cohorts.

In this study, up to 9.9% of the participants had severe pain and discomfort, while ADL was significantly affected in 10.4% of the participants. It is therefore imperative to institute therapeutic measures in pregnant women with MSDs. We recommend that MSDs in pregnancy should be managed by a multidisciplinary team of obstetricians, orthopedic surgeons, physiotherapists, and radiologists. For severe and disabling conditions, imaging, and other diagnostic workup is required for proper diagnosis. Conservative symptomatic therapy with analgesics, bed rest, muscle relaxants, and orthotic devices are usually sufficient. Preventive measures should also be instituted for patients who have a significant risk for MSDs.

Limitations of the study

A major limitation of this study is the hospital-based study design. This has possible selection bias and may have limited the scope of the study. Pregnant women who do not attend ANCs may not have been sampled. For future research, we recommend a wider community-based study to address this limitation, and to assess the impact of pregnancy-related MSDs on pregnancy outcomes. Despite the limitations, the study has highlighted the pattern and risk factors of pregnancy-related MSDs in our environment.

 Conclusion



LBP, muscle cramps, and joint pains were the leading MSDs among our cohorts. A majority of pregnant women will experience one or more MSDs during pregnancy with a prevalence rate ranging from 23 to 56.8%. However, most of these conditions are of mild to moderate intensity with about 12% having severe pains and discomfort. Increasing gestational age, multigravidity, and occupation were risk factors for MSDs in pregnancy among our participants. This will help attending physicians to be able to institute early preventive measures for the high-risk group and appropriate therapeutic measures to minimize the biomechanical and psychosocial impact of MSDs on pregnancy.

Disclosure

Ethics Approval and Consent to Participate: The Research and Ethics Committee of University of Nigeria Teaching Hospital Ituku-Ozalla gave approval for the study.

Consent for publication: Not applicable

Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Authors' contributions: NOO and BCO were involved in conceptualizing the study. NOO, COC and EOV were involved in the study design and data collection. NIO, OAL and COC were involved in data analysis and interpretation. NOO drafted the manuscript. COC, NIO, BCO, EOV and OAL were involved in critical revisions of the manuscript. All authors read and approved the final manuscript.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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