Correlation of Low Back Pain with Core Muscle Strength in Primigravida Indian Females

Low back Pain in Primigravida Indian Females

International Journal of Health and Rehabilitation Sciences Volume 3 Issue 1

March 2014

Abstract:

Background: Core stability of trunk is a basic function of both the local and global muscles. But there is insufficient research based data to determine the cause or ascertain how low back pain might be related to any of the particular features of pregnancy especially the core muscle strength.

Objective: To study correlation between low back pain and core muscle strength amongst the pregnant females.

Materials and Methods: 148 primigravida females (mean age 21.36 ± 1.54) in their 2nd trimester with complaints of backache were given VAS and Roland Morris Questionnaire to fill in. The core strength was assessed using pressure biofeedback unit while performing ‘drawing in’ maneuver in supine crook lying.

Results: Study showed negative correlation between core muscle strength and intensity of low back pain [r = - 0.489, p < 0.05] and negative correlation between core muscle strength and disability related to low back pain [r = - 0.536, p < 0.05]

Conclusion: Core muscle strength is an important factor for modulation of pain as well as for controlling its other associated disabilities. Thus, this may support the importance of Ante-natal exercises which includes core strengthening, to alleviate back pain and disability related to it during pregnancy.

Keywords: Low back pain, Core muscle strength, Pregnancy, Roland Morris disability questionnaire.

INTRODUCTION:

Pregnancy is a period of drastic physiological and anatomical changes in almost all the body organs of a pregnant female. The increase in the abdominal girth as a result of enlarging uterus leads to stretching of the abdominal muscles thus reducing their efficacy of contraction. The discomfort caused by the low back pain can have substantial impact on life during pregnancy; this can interfere with activity that ranges from basic activities of daily living such as walking and dressing to many work related functions. 

Core stability of trunk is a basic function of both the local and global muscles. But more so over, the local muscles have higher tasks in maintaining core stability and may be directly related to back pain. Abdominal muscle exercises are the key component of prenatal and post natal physiotherapy programs. The ability to perform these exercises during pregnancy and immediately post pregnancy has been questioned due to musculoskeletal structural adaptations occurring in the trunk. 

There is general consensus in the literature that there is reduction in the core muscle strength in the 2nd and the 3rd trimester. But there is insufficient research based data to determine the cause or ascertain how low back pain might be related to any of the particular features of the gestation process or the pregnancy especially the core muscle strength. And though several studies have quoted that there is reduction in core muscle strength in normal individuals with low back pain, there is no evidence to state whether this is true in case of pregnancy related low back pain. Thus this study aimed at assessing the correlation of low back pain with core muscle strength.

MATERIALS AND METHODS

Ethical approval was taken from the institutional ethical committee and only 2nd trimester females were included. 148 pregnant primigravida females with mean age 21.36 ± 1.54 (Table 1) were selected conveniently from primary and secondary health care centers. 2nd trimester primigravida nulliparous females between 20– 30 years of age were included and any females with history of low backache before conceiving; history of abortion or any other complication; twin pregnancy; history of any abdominal surgery; history of mechanical dysfunctions like prolapse intervertebral disc; lysthesis were excluded. After taking written consent from primigravida pregnant females; general information was documented. 

All the subjects were given the Visual Analogue Scale (VAS) and the Roland Morris Disability Questionnaire (Self informed) to fill, in their desired languages. All the subjects had to answer the questionnaire depending on their present status in terms of severity of pain and disability. The visual analogue scale meets the scientific criteria and is suitable for the objective measurement of intensity of pain and self-assessment measures are known to have better correlation with pain and disability than objective measures which use physical performance test. Therefore to assess low back pain related disability in pregnant women we used Roland Morris Disability Questionnaire which is a validated scale that reflects limitations in different activities of daily living in subjects with low back pain. 

Core Muscle Strength Evaluation All the subjects were asked to empty their bladder before the test. Subjects were positioned supine crook lying with hip flexed at 45 degrees. Subjects were given proper instructions about how to activate transverses abdominis muscle. The activation of transverses abdominis was confirmed with palpation. The inflatable cuff of the pressure biofeedback unit was placed under the hollow of the lumbar spine (between L1 and S1). The cuff was inflated to the baseline pressure of 40mmHg. The subjects were then asked to take a relaxed breath and while expiration to draw in the abdominal wall towards the spine so as to contract the deep abdominal muscles, raising the pressure up to 10mmHg and recommence the breathing and hold up to 10 seconds. The pressure biofeedback unit (Chattanooga Group, USA.) used in the abdominal drawing in maneuver with palpation has been shown to be reliable method in measuring the transverses recruitment.

The examiner observed for the pressure changes in the biofeedback unit dial, the pelvis and trunk for any movements and palpated for the correct activation of transverses abdominis placing the thumb, medial and inferior to the anterior superior iliac spine. If the pressure raised up to 10 mmHg in the absence of spinal or pelvic movement and without bulging of the abdomen, the test was said to be performed optimally. The test was repeated three times and the maximum pressure only was recorded. 3 minutes rest was given after each test.

Statistical Analysis

Data were analyzed using SPSS version 17.0. Spearman’s correlation test was applied to establish the correlations of low back pain with core muscle strength. A 5% level of probability was used to indicate statistical significance.

RESULTS

In Table 1, the descriptive statistics regarding Age, Week of pregnancy, VAS score, Roland Morris Disability score and Core Muscle strength of the Subjects is depicted. Figure 1 and 2 shows negative correlation between core muscle strength and intensity of low back pain [r = - 0.489, p < 0.05] and negative correlation between core muscle strength and disability related to low back pain [r = - 0.536, p < 0.05] respectively.

DISCUSSION

There is reduction in core muscle strength in normal individuals with low back pain but there is no evidence to state whether this is true in case of pregnancy related low back pain. This study assessed the correlation of low back pain with core muscle strength in 148 primigravida Indian females.

There is fair linear and negative correlation between core muscle strength and intensity of low back pain in the 2nd trimester. (Figure 1) As the abdominal muscles stretch to accommodate the growing fetus, their ability to help stabilize the lumbo-pelvic region decreases. With the anterior shift of the center of gravity, there is increase in the moment arms of the deep core stabilizers putting them at a mechanical disadvantage. The burden of stability shifts to the paraspinal muscles, which get strained at the time when they may be shortened from the increased lordosis of the lumbar spine leading to low back pain. Anterior pelvic tilt increases with increased lumbar lordosis. This altered biomechanics, in combination with relaxation of the pelvic and sacroiliac joints under the influence of hormone relaxin may further increase the strain on the pelvis and low back giving rise to pain.

Although this might be true, the fair correlation between core muscle strength and intensity of pain suggests that there might be factors other than core muscle strength which might be responsible for the pain in the 2nd trimester. A review on back pain in pregnancy has suggested a hypothesis that the muscle fatigue accumulates throughout the day and culminates in the low back pain. A study on postural changes associated with pregnancy showed a significant inverse relation of changes in lordosis and low back pain during pregnancy.

There is good correlation between core muscle strength and disability related to low back pain in the 2nd trimester of pregnancy which is linear and negative. (Figure 2) With common concept of leading normal life throughout pregnancy, the pregnant women are forced into performing demanding tasks. Although these females may sustain such demanding tasks in their thresholds such as long hours of standing, lifting heavy weights, frequent bending and other household chores in the early 2nd trimester, but as the pregnancy progresses it may become difficult for them to cope up with the same demands with other musculoskeletal complaints setting in. These instrumental activities require good proximal stability which can only be provided by the deep or local core stabilizers of the trunk. One study states that core stability is an essential component while performing any tasks, especially those tasks which are demanding and requires sustenance of posture for long. In absence of this, it becomes difficult to sustain postures of long or perform heavy tasks, reducing the productivity, giving rise to complaints of low back pain due to increased stresses on the spine.

This correlation shows that disability indirectly suggests reduced core muscle strength or inability of the local core system to stabilize the spine. A review on pregnancy related low back pain states that as the pregnancy advances, the abdominal muscles lose their ability to perform function of maintaining body posture, causing the lower back to support the majority of the increased weight of the torso. This explains the negative linear correlation of core strength with disability in the 2nd trimester, which simply means better the core strength, less the disability and vice versa.

CONCLUSION:

There is significant correlation of Core muscle strength and Intensity of low back pain as well as significant correlation of Core muscle strength and Disability associated with the low back pain in 2nd trimester of pregnancy. Therefore we can say that core muscle strength is an important factor for modulation of pain as well as for controlling its other associated disabilities. Thus, this may support the importance of Ante-natal exercises which includes core strengthening, to alleviate back pain and disability related to it during pregnancy.

Zende Devyani S, Shimpi Apurv P

www.ijhrs.com

References and Article at:

http://www.scopemed.org/fulltextpdf.php?mno=158591