ORIGINAL ARTICLE
Year : 2017 | Volume
: 11 | Issue : 2 | Page : 58--65
Movement control impairment tests in patients with low back pain and healthy controls and its correlation with clinical measures
Alagappan Thangamani Ramalingam1, SN Senthilkumar2, Shaikh Rahila Banu Mohammed Hanif1, Solanki Krutikaben Rameshbhai1, Surti Aatekabanu Mohamed Kasim1,
1 Department of Physiotherapy, Sarvajanik College of Physiotherapy, Surat, Gujarat, India
2 Department of Physiotherapy, SJ Nursing Home, Nagercoil, Tamil Nadu, India
Correspondence Address:
Alagappan Thangamani Ramalingam
Lecturer in Physiotherapy, Sarvajanik College of Physiotherapy, Surat, Gujarat
India
Abstract
BACKGROUND: To find out whether there is any movement impairment difference in the normal mechanics of musculoskeletal system between low back pain (LBP) patients and healthy individuals, applying battery of movement control impairment (MCI) tests and also relationship of diagnosis to major clinical measures.
METHODS: Design is a case–control study. Three-trained physiotherapists executed a test battery of six tests, for which the reliability has been shown to be acceptable. A total of 180 participants, ninety LBP patients and ninety age-matched normal individuals were recruited to participate in the study after given consent. The differences between the groups were analyzed using the effect size (ES) (d). Chi-square test with cross-tabulation was done to find out odds and risk ratios of the participants to represent or remain in the patient group. A correlation analysis was done between all the movement impairment tests and the clinical measures such as numerical pain rating scale, straight leg raising, pain location, flexion, and extension ROM and pain duration.
RESULTS: This study results demonstrated that there is a difference between participants with and without back pain which could be a diagnostic and in clinical practice may help to identify subgroups of patients in LBP. Tests such as one leg standing, rocking backward, and prone knee flexion are negatively related to back pain functional outcome indicating more difficulty in function if they are positive with LBP patients. There was no difference found regarding the presence or positive test result between the acute and chronic pain patients.
CONCLUSION: The present study concluded that there was a significant difference between patients with LBP and normal individuals without back pain in actively controlling the movements of the low back. The ES between patients with LBP and healthy controls in movement control is large. Moreover, the pain score and extension range of motion are not related to any of the MCI tests.
How to cite this article:
Ramalingam AT, Senthilkumar S N, Mohammed Hanif SR, Rameshbhai SK, Mohamed Kasim SA. Movement control impairment tests in patients with low back pain and healthy controls and its correlation with clinical measures.Physiother - J Indian Assoc Physiother 2017;11:58-65
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How to cite this URL:
Ramalingam AT, Senthilkumar S N, Mohammed Hanif SR, Rameshbhai SK, Mohamed Kasim SA. Movement control impairment tests in patients with low back pain and healthy controls and its correlation with clinical measures. Physiother - J Indian Assoc Physiother [serial online] 2017 [cited 2023 Mar 23 ];11:58-65
Available from: https://www.pjiap.org/text.asp?2017/11/2/58/223699 |
Full Text
Introduction
Low back pain (LBP) is one of the major cause for disability, work absenteeism in developed and developing countries alike which incurs enormous expenditure in the current health-care setting.[1],[2],[3],[4],[5] Epidemiological studies have reported that 50%–80% of adults in the general population will suffer from LBP at some stage in their lifetime.[6] Etiopathogenetic studies have reported that most individuals will recover within a month,[7] most people will have the recurrence of pain episodes within a 12-month period.[8],[9] The possible underlying reason for the remission after a period could be as previously postulated by Sahrmann that impaired movement control and lack of awareness of maladaptive patterns perpetuated LBP.[10] Research studies have reported variously on this thorough evaluation of motor control impairment among LBP patients toward identifying a valid and reliable diagnostic criteria and classification system. Dankaerts et al. reported on interobserver reliability of MC tests, while Van Dillen et al. used a whole package of the physical examination items to categorize in an impairment dysfunction group. Both the above studies evaluated on patients suffering from LBP.[11],[12] While Luomajoki et al. in a blinded-observational study evaluated ten movement control tests in patients with LBP on MC tests and subsequently evaluated a battery of MC tests for its reliability on comparing both LBP and non-LBP patients.[13]
Movement control impairment (MCI) tests involve various positions during testing and a normal response based on biomechanics is expected. The clinical examination of the low back predominantly involves examination of patients in both standing and lying position. In standing, therapist can observe whether patient is in correct position or not, and the therapist can check spasm, tenderness, and swelling in back region. Range of motion (ROM) assessment of spine is done in standing position. In prone or supine lying down position, straight leg raising (SLR) test, neurological examination, and assessment of adjacent joint such as SI joint can also be done. Hence, positional or postural assessment of spine and appendages of the body might give an understanding of what is otherwise a normal reference position. This assessment in turn might give a clue of deviation through motor control impairment tests as motor control impairment tests are commonly done in the abovementioned positions in addition to few other positions such as sitting. We expect that exploring this further might help in classification of LBP of nonspecific category (NSLBP).[14]
The classification of LBP is very much varied in different, and no widely accepted single system of classification is being used.[15],[16],[17] However, to the review done by us, classification of LBP based on the distribution of pain as predominately axial (localized pain to the low back) or radicular (pain radiating to the lower limbs in a dermatomal pattern with or without accompanying LBP) is particularly relevant because to know the distribution of pain is necessary for proper diagnosis and treatment. This simple classification system might provide a clinically focused framework to drive the diagnostic and therapeutic decision-making processes that arise in the routine care of patients with LBP in a much better way.[18],[19] However, the differential diagnosis of LBP is broad but commonly involves lumbar spine structures that include the intervertebral discs, facet joints, SI joints, and paraspinal muscles.[20] In patients of axial LBP, the intervertebral disc can be a source of pain in up to 40% of cases, and these patients tend to be younger (age <45 years).[18],[21],[22] Axial LBP attributed to the lumbar facet joints is affect almost 15% to 30% of patients, and the onset of pain of lumbar facet is generally insidious and it occurs more frequently in population with age of >65 years.[18],[23] In some patients, pain may be localized to the paraspinal muscle region with or without radiation to the groin area, thigh, or occasionally distal to the knee.[24],[25] SI joint pain occurs in 15% to 30% of population with axial LBP.[26] Patients of LBP will often complain of pain in the gluteal or paraspinal (below the fifth lumbar vertebra) regions with or without radiation to the thigh, but some patients may have referral pain distal to the knee and that is about 28%. Similar to axial LBP, the differential diagnosis of radicular LBP is broad, but approximately, 90% of cases in the nonelderly are caused by a herniated intervertebral disc at the L4–L5 or L5–S1 level of spine.[27],[28] Hence, it would be appropriate to add location of pain as a relevant clinical indicator and analyze whether movement impairment tests would identify it, which is why this clinical indicator is added into this study.
The movement impairment patterns of low back are important for physiotherapists when we consider that the detection of faulty movement is a key competence of physiotherapy in LBP. Moreover, the evidence of a difference between movement patterns in patients with LBP and individuals without LBP is limited.[10],[13] For movement impairment patterns, motor control dysfunctions [29],[30] and MCI [31],[32] are used synonymously. O'Sullivan [31] describes that in patients with LBP, reduced MC, and excessive movement increases pain. Sahrmann [10] theory of “relative flexibility” suggests that movement occurs through the pathway, in which resistance is so minimal, for example, if movement of hip is relatively stiff compared to that of the low back, then movement is more likely to occur in the back, leading to a back pain problem. In patients with back pain, reliable observation of variations in the movement control of the low back is very important,[10],[29],[30],[31] and reliability of movement control tests has been evaluated in the earlier studies. Dankaerts et al.[11] reported an almost perfect agreement with k = 0.96 and percentage agreement 97% between two examiners rating a classification of motor control dysfunction. White and Thomas [33] study of the reliability of the Movement System Balance's, 16 tests approach developed by Sahrmann, found a satisfactory reliability between raters. However, the difference between movement patterns in patients with back pain and individuals without LBP received little attention from these previous studies of these tests. In a previous study, Luomajoki et al.[13] reported of significant differences in effect sizes (ESs) in this battery of tests on a scientific underpinning that this analysis amounts to clinical trials of Phase I diagnostic research in which patients with LBP compared against controls without LBP.
Hence, in this study, we attempted to find the ES of the differences and evaluate whether there is a difference between patients with LBP and healthy controls in a test battery (six tests) score for movement control of the lumbar spine in a different set of population. Furthermore, we wanted to explore whether there is an association between all the movement impairment tests and the clinical measures such as pain (numerical pain rating scale), SLR, pain location, flexion and extension ROM, and pain duration.
Methods
Study design
The hypothesis was tested using a case–control study design. The participants were observed in standardized manner by performing a set of six active movement control test for lower back in the patients of LBP and healthy individual after informed consent was obtained from all patients. The testing therapists were not blinded to the patient and healthy groups. Ethical approval was obtained from the Institution. We except that undertaking this observational case–control study may add further evidence toward diagnostic criteria in the assessment of nonspecific LBP and correlation to clinical measures. Furthermore, this may throw light into the subgroup of nonspecific LBP and criteria for diagnostic tests.
Subject
A total of 90 participants from the different private physiotherapy clinics were included in the study. Exclusion criteria were serious pathologies such as nonhealed fractures, anomalies, tumors, and acute trauma. The patients with very acute LBP excluded as well, as the pain may have prevented them from accomplishing the tests. The remaining ninety participants were a mix of people recruited voluntarily from those friends, relatives accompanying patients to the clinics mentioned above and friends, relatives of physiotherapy colleagues working in the institution where the study is conducted.
Tools
Movement control impairment tests
Three-trained physiotherapists who had good experience in musculoskeletal practice scored the performance of the participants using six movement control tests resulting in score of 0–6 positive tests. Given the statistical significance and biomechanical significance of the battery of tests through the tests done in the previous study, we chose the same battery of tests in this population [Appendix 1 [SUPPORTING:1]].[13] Participants had never performed any of the tests before, and they were given standardized instructions. If any of the patients were not able to understand how to perform any of the tests, it was explained repeatedly by the therapist and even demonstrated by the therapist. We had permitted free trials for every MCI tests. Three trained physiotherapists watched the patients individually and independently rated test performance.[13]
Numeric Pain Rating Scale
The Numeric Pain Rating Scale (NPRS) which is being used as a standardized psychopathologic marker for severity of pain in most research studies is used in this study to measure pain intensity in adults with acute and chronic pain.[34],[35] NPRS is numeric version of visual scale, in which the participants selects a whole number from 0 to 10. And that number will show the intensity of the pain of the participant. The NPRS scale contains 11 points which ranges from 0 to 10. In which, 0 represents one pain extreme (e.g., no pain) and 10 represents other pain extreme (e.g., worst pain you can tolerate.[36] Therapist asked the patient how severe the pain was and asked to indicate the value numeric value that describes the pain intensity.[37]
Straight leg raising test
Neurodynamic tests check the mechanical movement of the neurological tissues as well as mechanical stress or compression. In SLR test, the therapist lifts the leg of the patient from the hip until patient complains of pain in the back or tightness in the back of the leg [38] SLR is a neural tension test which is also used to rule out neural tissue involvement because of space-occupying lesion such as lumbar disc herniation.[39]
The Back Pain Function Scale of Stratford
Stratford et al. developed the Back Pain Function Scale to evaluate functional ability in patients with back pain. The authors are from McMaster University Appalachian Physical Therapy (Georgia) and Virginia Commonwealth University.[40] The tool has a good test–retest reliability and high-internal consistency has been used a standardized tool for assessing functional ability in patients suffering from back pain.
Range of motion
Measurement of ROM of lumbar spine was done using a standard, flexible tape measure. Various techniques have been described for using measure tape, but generally, it involves measuring change in linear distance between two landmarks after movement is done (Schober's method).[41],[42]
Pain duration
Pathogenicity of an injury defined on the basis of pain duration and the widely prevalent accepted form of classification is acute, subacute, and chronic. We used the same classification here in our study, that, any pain within 6 weeks is that injury is in acute phase, any pain between 6–12 weeks as subacute phase, and any pain lasting beyond 6 weeks to be chronic injury.
Statistical analyses
Data collected were cleaned for paucity before the analysis and the categorical variables presented in percentages and numerical variables in terms of mean and standard deviations for the demographical and clinical outcomes. We compared the mean number of positive tests in the two groups. The differences between the groups were analyzed by the ES (d). The ES (d) is the difference of the means divided by the mean standard deviation of the groups. ES with d<0.2 are considered small, d >0.5 moderate and d >0.8 large.[43] Chi-Square test with cross-tabulation was done to find out odds and risk ratios of the participants to represent or remain in the patient group. A correlation analysis was done between all the movement impairment tests and the clinical measures such as numerical pain rating scale, SLR, pain location, flexion and extension ROM, and pain duration. Logistic regression analysis was done to find the presence of the movement control tests in acute and chronic back pain patients. Data were analyzed using IBM SPSS Statistics for Windows, Version 20.0. Armonk, NY: IBM Corp. Statistical significance was set at P < 0.05 (two-tailed).
Results
The present study collected data from 180 participants, in which 90 are patients with symptoms of LBP defined and mentioned in the classification in our study and other 90 are age-matched normal individuals. The personal demographical and clinical data of the participants are given in [Table 1]. Moreover[Table 2] and [Table 3] show the presence or absence of six MCI tests among the LBP patients and normal individuals as well as the odds and risk ratios for being present in either of one group [Figure 1], [Figure 2], [Figure 3], only three test results are graphically shown]. The result indicates that except the pelvic tilt tests all the other five MCI tests are significantly positive more among LBP patients than normal individuals without back pain. [Table 4] shows the relationship between MCI tests and clinical and functional measures in LBP patients represented as correlation index.{Figure 1}{Figure 2}{Figure 3}{Table 1}{Table 2}{Table 3}{Table 4}
Discussion
This study was undertaken with an aim to study a battery of MCI tests involving movements of the lumbar spine in its ability to identify movement impairments in patients with and without LBP. Furthermore, we wanted to explore whether the set of movement impairment tests and the clinical measures such as pain (numerical pain rating scale), SLR, pain location (centralized/peripheralized), flexion and extension ROM, and pain duration(acute/chronic) are related.
The tests assess flexion, extension, side flexion, and rotation movement control of lumbar spine. The tests were performed in the order mentioned above after piloting on 10 participants to study the face validity of the tests. Our results were also done in the same order as the previous study based on the pilot study. However, except for all the tests but for one, the pelvic tilt most of the participants in the patient and control group reported of difficulty in comprehending the performance. Moreover, it was reported in the earlier study by Luomajoki et al. that evaluators of these tests to have sufficient experience in musculoskeletal physiotherapy to assess with confidence.[13] Despite our attempts with our assessors having experience in musculoskeletal physiotherapy as well as fluency in the native language as the patients were not able to comprehend pelvic tilt. The other tests were performed well-reflecting better reliability like the previous study.
[Table 2] reflects the clinical outcome data after performance of the tests. Our results show three tests (one leg stance, sitting knee extension, and prone knee flexion) with relatively high number of positive tests (>65%) than the other three tests in other words, possibly high sensitivity among all the tests used to study. Luomajoki et al. reported of adequate construct validity of the battery of tests used as a clinical instrument.[13] However, results from our study suggest only 3 out of 6 tests to be adequately better in identifying the pathology of the condition in low back problems. The remaining three tests, waiter's bow, rocking backward, and pelvic tilt are less efficient than the other three in picking the number of positives in this given population. Luomajoki et al. mentioned about the necessity of the gold standard instrument to substantiate the findings of MC tests in his study after analyzing the face and construct validity of this battery of tests. Hence, the inference of our results for the three positive tests need to weighed with caution until further substantial evidence on MC tests are established.
[Table 4] reports of correlation between the MC tests and clinical measurements commonly used in the examination of patients suffering from LBP. Among the clinical measurements, NPRS and none of the MC tests showed any effective correlation suggesting that most of the patient group were able to perform the test given the movement impairment. The patient population in our sample consisted of 69% chronic low back problems, but the chronicity did not have any significant effect on performance of the tests. Moreover, equally most of the patients with regard to the functional scale fell into the category of moderately functional (77%). Tests such as one leg standing, rocking backward, and prone knee flexion are negatively related to back pain functional outcome indicating more difficulty in function if they are positive with LBP patients. As we did not categorize this group of NSLBP, we cannot be sure of the exact pathology of the patient population we had taken for this study, and it is unsure whether MC tests we applied were on patients with less structural deviation. Hence, whether the effect of MC tests as a structural differentiation tests need to be studied further. The other clinical measures have weak correlation (0.2–0.4) with the MC tests implicating whether these battery of tests were effective a clinical instrument in the diagnosis of the patients suffering from LBP, which need to be studied further.
The ES between patients with LBP and healthy controls in movement control is Cohen's d is 3.4 calculated through mean difference and pooled standard deviation or partial η2 = 0.731 calculated through variance for patients which is very huge and large.[43],[44] This indicates that the battery of tests is capable of being present with chronic LBP patients. The ES was calculated only for five tests excluding pelvic tilt as the participants both patients and normal individuals were having difficulty in understanding and performing the pelvic test. As this study is a case–control study, the odds and risk ratios were calculated to know the ES difference between LBP patients and normal controls [Table 3]. The values were indicating that the movement control tests present with back pain patients than normal controls.[45]
Luomajoki et al. study also reported a significant difference between patients with LBP and participants without back pain regarding their ability to actively control the movements of the low back. The ES between patients with LBP and healthy controls in movement control was also almost similar like the present study.[13] This study results demonstrated that there is a difference between participants with and without back pain which could be a diagnostic and we did not classify a subgroup of patients in LBP. If the pain duration is more or chronic condition one leg stance and prone knee flexion tests are going to be sensitive with those patients.[35] Moreover, one leg stance test was positively correlated with peripheralization of pain. Sitting knee extension test and prone knee flexion negatively related indicated that whoever had <80° of SLR range showed positive for the above tests. Moreover, the flexion ROM of lumbar spine contributed negatively to the test results of flexion movement control tests such as waiter's bow, sitting knee extension, and prone knee flexion indicating more of lumbar flexion observed with positive test results. This supports the theory of relative flexibility by Sahrmann.[10] However, the pain intensity and extension ROM were not at all related to MCI tests. According to O'Sullivan, up to one-third of patients with LBP are estimated to have MCI.[32] Moreover, overall from the findings of our study, there was no difference found regarding the presence or positive test result between the acute and chronic pain patients. Further studies need to be done with subgroup analysis to identify on the group of NSLBP patients that these MC control tests are effective.
Conclusion
The present study concluded that there was a significant difference between patients with LBP and normal individuals without back pain in actively controlling the movements of the low back. The ES between patients with LBP and healthy controls in movement control is large. However, most of the clinical measurements used in the assessment of LBP are not related to any of the MCI tests, and further studies are required to establish as to which subgroup of NSLBP were these MC tests are effective.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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