http://informahealthcare.com/ptp ISSN: 0959-3985 (print), 1532-5040 (electronic) Physiother Theory Pract, Early Online: 1–10 ! 2014 Informa Healthcare USA, Inc. DOI: 10.3109/09593985.2014.959144
RESEARCH REPORT
Comparing core stability and general exercise on chronic low back pain patients using three functional lumbopelvic stability tests MohammadBagher Shamsi, PhD, PT1,2, Javad Sarrafzadeh, PhD, PT1, and Aliashraf Jamshidi, PhD, PT1 Physiotherapy Department, School of Rehabilitation Sciences, Iran University of Medical Sciences (IUMS), Tehran, Iran, 2Rehabilitation and Sport Medicine Department, School of Paramedicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Abstract
Keywords
It is a matter of controversy whether core stability exercise is preferred to other types of exercise for chronic low back pain. Lumbopelvic stability is an important element in low back pain. No study was found using lumbopelvic stability tests in comparing core stability and other exercises. The single leg squat, dip test, and runner pose test appear to be suitable as tests for lumbopelvic stability. The aim of this study was to compare ‘‘core stability’’ and ‘‘traditional trunk exercise’’ using these tests and also the Oswestry disability questionnaire and pain intensity. Twenty-nine non-specific chronic low back pain subjects were alternately allocated in one of the two exercise groups. For both groups, a 16-sessions exercise program was provided. Before and after training: (1) video was recorded while subjects performed the tests; (2) Oswestry disability questionnaire was completed; and (3) pain intensity was measured by visual analogue scale. The test videos were scored by three physiotherapists. Statistical analysis revealed a significant improvement in stability test scores (p ¼ 0.020 and p ¼ 0.041) and reduction in disability (p50.001) and pain (p50.001) within each group. No significant difference was seen between two groups in the three outcomes p ¼ 0.41, p ¼ 0.14, and p ¼ 0.72. Insignificant differences between the two groups may indicate either non-specificity of CSE to increase lumbopelvic stability or equal effectiveness of TTE and CSE on improving LPS. The non-significant differences may also be attributable to the lack of sensitivity of our tests to assess stability change in two groups after training given the relatively small sample size.
Core stability exercise, dip test, lumbopelvic stability, runner pose test, single leg squat, traditional trunk exercise
Introduction The vast majority of low back pain (LBP) patients (up to 90%) are labelled as having non-specific LBP, which is defined as symptoms without a clear specific cause, that is, LBP of unknown origin (van Tulder and Koes, 2007). Non-specific LBP is usually classified according to its duration as acute (less than 6 weeks), sub-acute (between 6 weeks and 3 months), or chronic (longer than 3 months) LBP (Refshauge and Maher, 2006). Most clinical practice guidelines endorse exercise for chronic LBP (CLBP) treatment (Costa et al, 2009), however, there is little evidence that a particular type of exercise is any better than another (van Tulder, Malmivaara, Esmail, and Koes, 2000). Strengthening trunk muscles is a common component of exercise programs for CLBP (Liddle, Baxter, and Gracey, 2004). Also, core stability exercise (CSE) has been considered as a treatment for LBP in recent years. The biological rationale for CSE is fundamentally based on the idea that the stability and control of the spine are altered in people with LBP (Costa et al, 2009). The aim of this exercise is re-education of the co-activation pattern in back muscles. Initial low-level isometric contraction of trunk stabilizing muscles (i.e. multifidus, transversus abdominis, and internal oblique) and their progressive integration into functional tasks is the essence of CSE (Richardson, Hodges, and Hides, 2004).
Address correspondence to Javad Sarrafzadeh, Physiotherapy Department, School of Rehabilitation Sciences, Iran University of Medical Sciences (IUMS), Tehran, Iran. E-mail: j.sarrafzadeh@ gmail.com
History Received 28 May 2013 Revised 17 June 2014 Accepted 21 June 2014 Published online 15 October 2014
It is a matter of controversy whether CSE is preferable to general exercise that includes traditional trunk exercises (TTE) for abdominal and back muscle strength. Some systematic reviews indicate that CSE is more effective than other types of therapy for the treatment of CLBP (Lederman, 2010). However, other studies state that both CSE and general exercises are equally effective. These suggest that improvements are due to the positive effects that physical exercise may have on the patient rather than on improvements in spinal stability (Lederman, 2010). Good evidence exists regarding benefits of exercise (generally) in CLBP (Hayden, Van Tulder, Malmivaara, and Koes, 2005; Henchoz and So, 2008). In the 1990s, traditional strengthening exercises were more popular than other types of exercise for patients with CLBP (Kasai, 2006). TTE could be expected to have positive effects and they were used in clinics, therefore, this exercise was chosen as control for the CSE in our study. Clinically, there is a belief that lumbopelvic stability (LPS) is an important element of injury prevention, and training of LPS will help to recovery from injury and improve performance (Willardson, 2007). LPS could be defined as the following: ‘‘The ability of an individual to attain and then maintain optimal body segment alignment of the spine (lumbar and thoracic), the pelvis, and the thigh in both a static position and during dynamic activity. Stability is attained and maintained by passive structures and with optimal muscle recruitment patterns, that is, without substitution strategies’’ (Perrott, Pizzari, Opar, and Cook, 2012). It is important to assess LPS properly. A number of functional tests for LPS have been reported in the literature. Some of these tests have a low level of validity, since the ballistic nature makes
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assessing them clinically difficult (Perrott, Pizzari, Opar, and Cook, 2012). Of the reported clinical tests for LPS, the single leg squat (SLS), dip test (DT), and runner pose test (RPT) appear to assess body segment alignment of the trunk, pelvis, and thigh in multiple planes, so they are suitable as tests for LPS (Perrott, Pizzari, Opar, and Cook, 2012). SLS and RPT are widely used and accepted for evaluation of injured runners (Plastaras et al, 2005). Interrater reliability of SLS has been reported as low to fair in some studies (DiMattia et al, 2005). Although visual-observation clinical tests do not have high reliability, they are used in clinics as a basis for clinical decision making (DiMattia et al, 2005). In a survey of the literature, lumbopelvic stability was not assessed with this type of functional test in studies comparing CSE and other types of exercises. Some authors consider the lack of a measure of stability in their studies on exercise for trunk stabilization as a limitation (Sherry and Best, 2004). The aim of the present study was to compare the effect of the two different exercise programs (CSE and TTE) using LPS, assessed using three functional tests, as the primary outcome measure. Patient disability and pain intensity were compared before and after the training as secondary outcome measures. The second aim of this study was to determine inter-rater reliability of the results for three assessors who scored the videos of participants performing the tests.
Materials and methods
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5 min). Based on the previous recommendations, a staged approach was followed for both groups (Appendix) (Koumantakis, Watson, and Oldham, 2005). This approach contained eight exercise levels of progressively increasing difficulty. In the first session, the exercises were explained and demonstrated to the participants. Core stability exercise In the CSE group, anatomy and function of local back stabilizing muscles and the way they could be activated were taught. The first four sessions were on local muscle contraction recognition. Then, low-load activation of these muscles was administered isometrically in minimally loading positions. Progressively, integration with dynamic function (activities that required spinal or limb movements) through incorporation of co-contraction of the stabilizing muscles into light functional tasks was included (Appendix). Heavier-load functional tasks with exercises similar to those performed by the participants in the TTE group were progressively introduced in the last six sessions of the program. To ensure correct activation of the transversus abdominis muscle, it was emphasized to the participants that the lower part of the anterior abdominal wall below the umbilical level needed to be ‘‘drawn in’’ with the action of this muscle. Also, bulging action of the multifidus muscle needed to be felt under the therapist’s fingers when they were placed on either side of the spinous processes of lumbar vertebrae, directly over the belly of this muscle (Richardson, Hodges, and Hides, 2004).
Study design The study design was a quasi-randomized controlled trial. Approval for the research was obtained from the ethics committee of Tehran University of Medical Sciences (TUMS). Participants As we used a new rating method for the functional tests (Perrott, Pizzari, Opar, and Cook, 2012), no relevant standard deviation value was found for sample size calculation. We made the assumption that 20 participants would be sufficient, so the study was started with 19 people in one and 20 in the other group. For functional tests, the standard deviation of all our participants at pre-intervention assessment was 9.04. Using this value, to detect a difference between groups with confidence interval of 8.5 (27.44–35.94) for power of 80% and a significance level of 0.05, a sample of 18 was calculated to be sufficient. Inclusion criteria for participants were having LBP for more than 3 months, age of 18–60 years, and pain intensity from 3 to 6 in the VAS scale. Participants had no history of having pathology or anomaly in lower limbs such as malignancy, inflammatory diseases, severe osteoporosis, arthritis, or bone diseases. Participants were classified as having CLBP based on history, imaging, and pain provocation tests. Pain provocation tests are claimed to be the most reliable of the palpatory tests in chronic non-specific LBP diagnosis and were our main clinical test (Airaksinen et al, 2006). Accompanying history, imaging and pain provocation test findings enabled us to confirm the classification as non-specific CLBP. Participants were assigned a number in the order that they entered the study. Those with odd numbers were assigned to the core stability exercise (CSE) group and those with even numbers to the TTE group. At the time of admission, the study was explained to participants and their informed consent was obtained. Interventions Common components of the two programs included a warm-up period (eight stretching exercises and stationary bicycling for
TTE For the TTE group, exercises activating the extensor (paraspinals) and flexor (abdominals) muscle groups were used. They were performed in a lying position commencing with simple movements and progressing to more difficult exercises (e.g. on a Swiss ball) (Appendix). An attempt was made to equalize the exercise dose for each group. In each session, the participants were instructed to perform their exercises as many times as they could with rest periods in between in the same session. However, the pure exercise time for each CSE and TTE group session was set to 20 and 14 (a total of 320 and 224) min, respectively. Based on the previous studies (Danneels et al, 2001), these times were selected to balance the groups estimated total trunk muscle force output. Participants who were absent for three consecutive, or five sessions in total were excluded. Participants were blinded in the sense that they were unaware of the existence of the two groups, however, they did know the exercises they were performing. Each group performed three exercise sessions for a week, a total of 16 sessions. An experienced physiotherapist was responsible for supervising both groups to perform the exercises correctly in the defined time duration. Outcomes Lumbopelvic functional tests Three LPS functional tests: (1) SLS (Figure 1); (2) DT (Figure 2); and (3) RPT (Figure 3) were used. Before and after the 16 training sessions, videos were recorded from a distance of approximately 3 m to the participants while performing these tests. Three physiotherapists (PhD candidates) with 3–10 years of practical experience were selected to score the tests. They had not participated in the study design and were not authors of this study. Before the observation, they received written instruction and an explanation on how scoring of the tests should be performed. They were blinded to which group each patient had been assigned.
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DOI: 10.3109/09593985.2014.959144
Figure 1. Single leg squat.
Exercise for chronic low back pain patients
Figure 2. Dip test.
Rating criteria for scoring the tests were based on a previous study (Perrott, Pizzari, Opar, and Cook, 2012). Fourteen key factors were defined for the tests’ scoring (DT and SLS: five each, and RPT four factors) (Tables 1–3). Each of the key factors for the tests had descriptive performance characteristics that represented either good or poor stability (Perrott, Pizzari, Opar, and Cook, 2012). Regarding rating criteria, three assessors rated the 14 key factors as good or poor for each participant. Each good factor was recorded as one and each poor factor as zero. In order to convert from a nominal to a continuous variable, the sum of scores (good ratings) for 14 factors from all three assessors (total test score) constituted the participant’s overall test score. Disability and pain All participants completed the Persian translated version of the Oswestry Disability Questionnaire (Mousavi et al, 2006) (0 ¼ no disability, 100 ¼ totally disabled), and their pain intensity was measured by visual analogue scale (VAS) (0 ¼ no pain, 100 ¼ pain as bad as it could be) before and after training. Statistical analysis Cohen’s kappa coefficient was used to assess inter-rater reliability of the three assessors’ test results. Independent-sample t-test was used to compare disability level, pain intensity, and participant’s test scores between the two groups: first, at the start of the study to confirm equality of samples; and second, at the end of the study to assess whether or not the changes in these variables during intervention were statistically different in the two groups. Paired t-test was used to investigate whether the three variables were changed by the intervention. Effect size for each group was calculated as the difference between mean values before and after the intervention divided by the standard deviation for
Figure 3. Runner pose test.
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Table 1. Single leg squat.
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Good 1. Overall impression Smooth, good-quality movement General control Controlled change-over between repetitions Ease of movement 2. Weight transfer Minimal translation of centre of mass Upright trunk 3. Lumbar Spine & Pelvic Alignment Minimal movement in all three planes Frontal plane: ASIS level Sagittal plane: minimal A-P tilt, rotation Lateral view: stable lordosis, minimal trunk flexion 4. Leg alignment Minimal movement out of the starting plane of movement. This takes into account the alignment of the limb, influenced by pelvic width, and Q angle at the knee 5. Foot alignment Neutral foot position – remains stable during movement
Poor Staggered movement Increased speed to attempt to control movement Effort to control movement Trunk ‘‘wobble’’ Discernible translation of centre of mass Trunk leaning forward or to side Extended time to transfer Discernible movement with pelvis tilting up or down Rotating toward or away from weight bearing leg, tilting in anterior or posterior direction Lumbar lordosis increasing or trunk flexion occurring Discernible movement out of the starting plane of movement Excessive pronation of foot during squat descent Externally rotated starting position of lower leg/foot
Table 2. Dip test. Good 1. Overall Impression Smooth, good-quality movement General control Controlled change-over between repetitions 2. Weight distribution Minimal weight on back leg Back leg remains oriented in the sagittal plane (i.e. no movement in frontal plane) Upright trunk 3. Lumbar and pelvic alignment Minimal movement in all three planes Frontal plane: ASIS level Sagittal plane: minimal A-P tilt, rotation Lateral view: stable lordosis, minimal trunk flexion 4. Leg alignment Minimal movement out of the starting plane of movement. This takes into account the alignment of the limb, influenced by pelvic width, and Q angle at the knee 5. Foot alignment Neutral foot position – remains stable during movement
Poor Staggered movement Increased speed to attempt to control movement Effort to control movement Trunk ‘‘wobble’’ Excessive weigh on back leg Abduction of back leg Trunk leaning forward or to side Discernible movement with pelvis tilting up or down, Rotating toward or away from weight bearing leg, tilting in anterior or posterior direction Discernible movement out of the starting plane of movement Excessive pronation of foot during squat descent Externally rotated starting position of lower leg/foot
Table 3. Runner pose test. Good 1. Overall Impression Smooth, good-quality movement General control 2. Weight distribution Minimal translation of centre of mass 3. Pelvic alignment Hip dissociation from pelvis – minimal pelvic movement Minimal A-P movement (anterior pelvic tilt) Minimal tilt in frontal plane (ASIS level) 4. Trunk alignment No rotation of trunk Trunk upright
the data. Between group effect size was the difference between two means divided by a pooled standard deviation. Minimal important difference (MID) for test scores was defined as one half a standard deviation (Norman, Sloan, and
Poor Jerky movement Effort to control movement Excessive trunk movement Inability to maintain centre of mass over weight-bearing leg Discernible movement of pelvis with the hip – no dissociation Discernable tilt in frontal plane Trunk rotation Forward flexion of trunk Trunk locked in extension
Wyrwich, 2003). Minimal detectable change (MDC) at the 90% confidence level was calculated using the formula (Stratford, 2004): MDC ¼ 1.96 standard error of measurement square root of 2.
Exercise for chronic low back pain patients
DOI: 10.3109/09593985.2014.959144
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Results Five out of 44 participants fulfilling the inclusion criteria dropped out during the study and 39 participants remained (19 participants in CSE and 20 in TTE group). Participant characteristics are presented in Table 4. There was a difference in age between groups with the TTE cohort being significantly older (p ¼ 0.015). Mean kappa coefficient value for inter-rater assessors reliability in both pre and post-training test scores was 0.30, indicating poor agreement (Table 5). There was no statistical significant difference between the groups on entry to the trial in test scores (p ¼ 0.79), disability (p ¼ 0.74), and pain (p ¼ 0.83). Statistical analysis revealed a significant improvement in LPS test scores (p ¼ 0.02) for both the CSE and the TTE group (p ¼ 0.041) and reduction in disability level (p50.001) and pain intensity (p50.001) within each group after the intervention period (Table 6). With regard to changes in outcomes (the difference between before and after treatment values), no significant difference was seen between CSE and TTE groups in the three variables of LPS (p ¼ 0.41), disability (p ¼ 0.14), and pain (p ¼ 0.72) (Table 6). The effect size due to CSE was 0.44 for LPS test scores, 1.50 for disability, and 3.34 for pain, and the effect size due to TTE was 0.23, 1.13, and 3.20, respectively. Between group effect sizes for LPS test scores, disability, and pain were 0.04, 4.88, and 1.18 all in favor of the CSE group (Table 6). MID for test scores at pre-intervention period for both groups was 4.6, and MDC for the CSE and TTE groups was 17.6 and 15.2, respectively.
Discussion This study compared core stability exercise and TTE in patients with chronic non-specific LBP. Over the course of 16 training sessions both groups improved LPS, as well as disability and pain Table 4. Participant characteristics.
Gender: Male Female Age/mean (SD) Height (cm)/mean (SD) Weight (kg)/mean (SD)
Core stability exercise group
Traditional trunk exercise group
6 13 38.5 (11.9) 166.7 (8.6) 68.9 (15.7)
6 14 47.7 (10.4) 163.7 (8.3) 73.1 (8.9)
Table 5. Inter-rater assessors’ reliability. Raters 1 and 2
Raters 1 and 3
Raters 2 and 3
Mean
0.26 0.28
0.30 0.25
0.34 0.37
0.30 0.30
Before intervention test After intervention test
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scores indicating that both forms of exercise were beneficial. This is a good outcome for both groups of participants. There were no overall between-group effects on these outcomes. However, our small sample size may have contributed to type two error. The effects of CSE in people with CLBP have been investigated in some studies. In a meta-analysis comparing CSE and TTE for CLBP (searching papers from 1970 to 2007) (Wang et al, 2012), in five clinical trials which fulfilled the criteria for this study, CSE was better than TTE for reducing pain and disability in short-term follow-up. However, no significant differences were observed between CSE and TTE in reducing pain at 6 and 12 months. No stability outcome measures were considered in this meta-analysis. In general, our results were consistent with the findings of the meta-analysis. However, some studies have shown better outcomes from CSE in comparison with TTE (Ferreira et al, 2007; O’Sullivan, Phyty, Twomey, and Allison, 1997). Stability of the spine is provided by the integrated relationship of three sub-systems: (1) active, (2) passive, and (3) control (Panjabi, 1992). While the function of each of these subsystems can be weakened through injury or disuse, it is hypothesized that training the active sub-system can re-establish function (Mills, Taunton, and Mills, 2005). The rationale for CSE is restoration of the ability of the neuromuscular system to control and protect the spine from injury. To achieve this, exercises are used to restore the coordination and control and also the capacity (i.e., strength and endurance) of the trunk muscles (Hodges, 2003). Although the essence of CSE is re-education of local or deep intrinsic lumbopelvic muscles, many believe that most torso muscles, and not only local ones, are important and their level of importance depends on their activity (McGill, 2001). In spite of the rationale for CSE, other authors (Koumantakis, Watson, and Oldham, 2005) believe that insignificant improvement in the CSE group outcomes versus TTE in their studies may indicate that CSE is more related to LBP patients who suffer from either gross spinal instability symptoms or pronounced sideto-side differences in the size of the multifidus muscle than to patients who do not present any signs and symptoms of clinical instability. As mentioned earlier, in spite of low reliability of visualobservation clinical tests, they can be used as a basis for clinical decision making (DiMattia et al, 2005). Intrarater reliability for the tests was not examined. One strength of the current study was the use of a total test score that most likely improved the ability to demonstrate a change in LPS that occurred rather than using a categorical rating method. This is important in clinical decision making but may have reduced the interrater reliability, as good reliability is difficult to obtain when raters are required to make fine discriminations (McHugh, 2012). Although the aim of CSE is enhancing spinal stability, insignificant differences between the two groups may indicate either non-specificity of CSE to increase lumbopelvic stability or
Table 6. Means, standard deviations (SD), effect size, and within and between group differences for the exercise groups following the intervention period. Core stability group Outcome measures
Before
a
After
Total test score 27.8 (9.2) 31.6 (7.9) Oswestry disability 51.1 (12.7) 33.3 (11.0) Pain intensity 52.4 (9.2) 15.9 (12.4) a
Sum of three raters’ score.
p Value for difference Effect size p ¼ 0.020 p50.001 p50.001
p Value for difference p Value for Effect between Between group difference size groups effect size
Traditional trunk exercise group
0.44 1.49 3.34
Before
After
27.1 (9.1) 29.3 (9.9) 49.8 (10.8) 37.4 (11.1) 53.0 (9.2) 14.9 (14.1)
p ¼ 0.041 p50.001 p50.001
0.23 1.13 3.20
p ¼ 0.41 p ¼ 0.14 p ¼ 0.72
0.04 4.88 1.18
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equal effectiveness of TTE and CSE on improving LPS. The non-significant differences may also be attributable to the lack of sensitivity of our tests to assess stability change in two groups after training given the relatively small sample size. Core stability components including strength, endurance, flexibility, motor control, and function have already been measured in previous studies. There are many functional tests that measure these factors. In addition, the pressure biofeedback unit was developed to assess the ability of the abdominal muscles to actively stabilize the lumbar spine (Jull et al, 1993). No study was found in the literature using tests of core stability as an outcome measure in comparing the effects of CSE and TTE. It is claimed that none of the studies on CSE actually has shown a relationship between improvement in LBP and spinal stabilization or core control (Lederman, 2010). Outcome measurements in previous studies have been pain, disability, LBP episodes, and health-related quality of life (Lederman, 2010). We believe that the novelty of our study lies in trying to specifically measure LPS to judge the effectiveness of these exercises on CLBP Limitations The intervention was a prolonged process lasting about 1.5 months. It was difficult to recruit sufficient participants who met the inclusion and exclusion criteria who were willing to participate for 6 weeks. The mean age was higher in TTE (48.7) than CSE (39.3) group (p ¼ 0.015), which can be considered as a drawback of systematic sampling (alternative allocation of participants in two groups). To have a more clear insight on the impact of different exercises on LPS, it is suggested that further studies be conducted using other methods to measure LPS such as biomechanical models, other functional LPS tests, and pressure biofeedback unit to more reliably assess the impact of different exercises on LPS.
Conclusion The present results provide evidence that both types of training enhance LPS and reduce pain and disability. However, there is no evidence that one type of exercise is more effective than the other in doing so.
Acknowledgements The authors thank Iran University of Medical Sciences Physiotherapy, Ph.D. students, Mr. Mehdi Zamanlou, Mr. Mahmood Akbari, and Mr. Mohammad Reza Pourahmadi for their kind assistance in test video scoring; Dr. Ali Amiri and his colleagues in the Physiotherapy Department of Rasool Akram Hospital (Tehran, Iran) for their cooperation; Dr. Amir Hosein Hashemian for his statistical advice; and Dr. Bahman Mehraban for his grammatical correction on the manuscript.
Declaration of interest The authors report that they have no conflict of interest. This work was part of a PhD project supported by the grants from Iran University of Medical Sciences.
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Appendix Stage 1
Core Stability Group
General Exercise Group
Isolated lumbar stabilizing muscle training Classic abdominal and back extensor training Physiother Theory Pract Downloaded from informahealthcare.com by Dokuz Eylul Univ. on 11/06/14 For personal use only.
Session Development of the percepon of the isolated isometric specific contracon of the stabilizing muscles Transversus abdominis muscle from: 4-point kneeling and lying posions, trying to hollow the lower abdomen
1-2
Mulfidus muscle from: stepping acvity while standing and raising contralateral arm, trying to feel the contracon of the opposite-side mulfidus muscle or from sing posion with therapist’s hands over the muscle
Precise repeon of the isolated isometricspecific co-contracon of the stabilizing muscles, increasing their contracon me Transversus abdominis and mulfidus muscles together from: sing and standing posions
3-4
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Upper and oblique abdominals from lying posion: with Knees straight (hands filling space between low back and exercise mat) and knees bent
Back extensors: liing trunk to neutral from prone posion with pillow under stomach and arms by the side Coordinaon: pelvic lng from lying, sing, and standing posions
Upper and oblique abdominals from lying posion: with knees straight, knees bent Back extensors: liing trunk to neutral from prone posion with pillow under stomach and arms by the side Exercises performed as illustrated for sessions 1 and 2
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Stage 2
Core Stability Group Session
General Exercise Group
Integraon of lumbar stabilizing muscle Classic abdominal and back extensor training acvity into light dynamic funconal tasks Control of neutral lumbopelvic postures Isolated movement of adjacent body areas, maintaining lumbar spine stability (ie, moving only hip or thoracic spine)
Abdominals from lying posion: heel slides, lower abdominal crunches
Control of neutral lumbopelvic postures and aggravang postures
Abdominals from lying: heel slides, leg slides, lower abdominal crunches
Stabilizing muscle isometric co-contracons with addion of external load to lumbar spine
Back extensors: bridging, liing trunk to neutral( prone posion with arms elevated), single-leg extensions from prone and 4-point kneeling posions
Back extensors: bridging, liing trunk to neutral from prone posion and arms in elevaon
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5-6
Hip horizontal abducon, heel slides, leg slides from crook-lying posion
7-8 Aggravang postures
Lumbopelvic control during movements and aggravang movements Sing on unstable base of support (hip extension movement only, lumbar spine only, thoracic only), 3-plane movement, cocontracons during normal-speed walking and other acvies
9-10
Abdominals from lying posion: straight leg lis toward ceiling, cycling exercises, leg slides, lower abdominal crunches Obliques: hip li from side-lying posion Back extensors: as in sessions 7-8
Exercise for chronic low back pain patients
DOI: 10.3109/09593985.2014.959144
Stage 3
Core Stability Group Session
General Exercise Group
Integration of lumbar stabilizing muscle Classic abdominal and back extensor training activity into heavy-load dynamic functional tasks Isometric co-contracons with addion of heavier external loads to lumbar spine Bridging exercise, co-contracons during leg cycling from supine posion, single-leg extensions from 4-point kneeling posion
Abdominals from lying posion: full abdominal crunches, straight leg lis toward ceiling, cycling exercises, leg slides Obliques: hip li from side-lying posion
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Back extensors: alternate arm/leg extensions from 4point kneeling and lying posions, single-leg bridging Swiss ball coordinaon exercises: alternate arm/leg lis sing on ball
11-12
Increasing complexity and load of exercises maintaining lumbar spine stability Single-leg bridging exercise, bridging exercise with an unstable base of support
13-14
Alternate arms/leg extensions from 4-point kneeling and lying posions and arm/leg lis sing on Swiss ball Funconal co-contracons during walking (increasing speed) and other acvies
Abdominals from lying posion: same leg and arm liing-lowering, full abdominal crunches, straight leg lis toward ceiling, cycling exercises, leg slides Obliques: advanced hip li from side-lying posion Back extensors: as in sessions 11-12 Swiss ball coordinaon exercises: abdominal curls on ball from prone posion, pulling legs toward chest
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Coordinaon exercises Single-leg bridging exercise with an unstable base of support, bridging exercise with rotator self-resistance, simultaneous arm and leg movements from supine posion maintaining lumbar spine stability, funconal cocontracons during walking (changing speeds) and other acvies
Abdominals from lying posion: same leg and arm liing-lowering, cycling exercises Obliques: full oblique abdominal crunches, li from side-lying posion Back extensors: as in sessions 11-12 Swiss ball co-ordinaon exercises: oblique abdominal curls on ball from prone posion, single-leg bridging
15-16
This appendix is a modificaon of the appendix of Koumantakis GA et al 2005 arcle.
RESEARCH REPORT
Comparing core stability and general exercise on chronic low back pain patients using three functional lumbopelvic stability tests MohammadBagher Shamsi, PhD, PT1,2, Javad Sarrafzadeh, PhD, PT1, and Aliashraf Jamshidi, PhD, PT1 Physiotherapy Department, School of Rehabilitation Sciences, Iran University of Medical Sciences (IUMS), Tehran, Iran, 2Rehabilitation and Sport Medicine Department, School of Paramedicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Abstract
Keywords
It is a matter of controversy whether core stability exercise is preferred to other types of exercise for chronic low back pain. Lumbopelvic stability is an important element in low back pain. No study was found using lumbopelvic stability tests in comparing core stability and other exercises. The single leg squat, dip test, and runner pose test appear to be suitable as tests for lumbopelvic stability. The aim of this study was to compare ‘‘core stability’’ and ‘‘traditional trunk exercise’’ using these tests and also the Oswestry disability questionnaire and pain intensity. Twenty-nine non-specific chronic low back pain subjects were alternately allocated in one of the two exercise groups. For both groups, a 16-sessions exercise program was provided. Before and after training: (1) video was recorded while subjects performed the tests; (2) Oswestry disability questionnaire was completed; and (3) pain intensity was measured by visual analogue scale. The test videos were scored by three physiotherapists. Statistical analysis revealed a significant improvement in stability test scores (p ¼ 0.020 and p ¼ 0.041) and reduction in disability (p50.001) and pain (p50.001) within each group. No significant difference was seen between two groups in the three outcomes p ¼ 0.41, p ¼ 0.14, and p ¼ 0.72. Insignificant differences between the two groups may indicate either non-specificity of CSE to increase lumbopelvic stability or equal effectiveness of TTE and CSE on improving LPS. The non-significant differences may also be attributable to the lack of sensitivity of our tests to assess stability change in two groups after training given the relatively small sample size.
Core stability exercise, dip test, lumbopelvic stability, runner pose test, single leg squat, traditional trunk exercise
Introduction The vast majority of low back pain (LBP) patients (up to 90%) are labelled as having non-specific LBP, which is defined as symptoms without a clear specific cause, that is, LBP of unknown origin (van Tulder and Koes, 2007). Non-specific LBP is usually classified according to its duration as acute (less than 6 weeks), sub-acute (between 6 weeks and 3 months), or chronic (longer than 3 months) LBP (Refshauge and Maher, 2006). Most clinical practice guidelines endorse exercise for chronic LBP (CLBP) treatment (Costa et al, 2009), however, there is little evidence that a particular type of exercise is any better than another (van Tulder, Malmivaara, Esmail, and Koes, 2000). Strengthening trunk muscles is a common component of exercise programs for CLBP (Liddle, Baxter, and Gracey, 2004). Also, core stability exercise (CSE) has been considered as a treatment for LBP in recent years. The biological rationale for CSE is fundamentally based on the idea that the stability and control of the spine are altered in people with LBP (Costa et al, 2009). The aim of this exercise is re-education of the co-activation pattern in back muscles. Initial low-level isometric contraction of trunk stabilizing muscles (i.e. multifidus, transversus abdominis, and internal oblique) and their progressive integration into functional tasks is the essence of CSE (Richardson, Hodges, and Hides, 2004).
Address correspondence to Javad Sarrafzadeh, Physiotherapy Department, School of Rehabilitation Sciences, Iran University of Medical Sciences (IUMS), Tehran, Iran. E-mail: j.sarrafzadeh@ gmail.com
History Received 28 May 2013 Revised 17 June 2014 Accepted 21 June 2014 Published online 15 October 2014
It is a matter of controversy whether CSE is preferable to general exercise that includes traditional trunk exercises (TTE) for abdominal and back muscle strength. Some systematic reviews indicate that CSE is more effective than other types of therapy for the treatment of CLBP (Lederman, 2010). However, other studies state that both CSE and general exercises are equally effective. These suggest that improvements are due to the positive effects that physical exercise may have on the patient rather than on improvements in spinal stability (Lederman, 2010). Good evidence exists regarding benefits of exercise (generally) in CLBP (Hayden, Van Tulder, Malmivaara, and Koes, 2005; Henchoz and So, 2008). In the 1990s, traditional strengthening exercises were more popular than other types of exercise for patients with CLBP (Kasai, 2006). TTE could be expected to have positive effects and they were used in clinics, therefore, this exercise was chosen as control for the CSE in our study. Clinically, there is a belief that lumbopelvic stability (LPS) is an important element of injury prevention, and training of LPS will help to recovery from injury and improve performance (Willardson, 2007). LPS could be defined as the following: ‘‘The ability of an individual to attain and then maintain optimal body segment alignment of the spine (lumbar and thoracic), the pelvis, and the thigh in both a static position and during dynamic activity. Stability is attained and maintained by passive structures and with optimal muscle recruitment patterns, that is, without substitution strategies’’ (Perrott, Pizzari, Opar, and Cook, 2012). It is important to assess LPS properly. A number of functional tests for LPS have been reported in the literature. Some of these tests have a low level of validity, since the ballistic nature makes
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assessing them clinically difficult (Perrott, Pizzari, Opar, and Cook, 2012). Of the reported clinical tests for LPS, the single leg squat (SLS), dip test (DT), and runner pose test (RPT) appear to assess body segment alignment of the trunk, pelvis, and thigh in multiple planes, so they are suitable as tests for LPS (Perrott, Pizzari, Opar, and Cook, 2012). SLS and RPT are widely used and accepted for evaluation of injured runners (Plastaras et al, 2005). Interrater reliability of SLS has been reported as low to fair in some studies (DiMattia et al, 2005). Although visual-observation clinical tests do not have high reliability, they are used in clinics as a basis for clinical decision making (DiMattia et al, 2005). In a survey of the literature, lumbopelvic stability was not assessed with this type of functional test in studies comparing CSE and other types of exercises. Some authors consider the lack of a measure of stability in their studies on exercise for trunk stabilization as a limitation (Sherry and Best, 2004). The aim of the present study was to compare the effect of the two different exercise programs (CSE and TTE) using LPS, assessed using three functional tests, as the primary outcome measure. Patient disability and pain intensity were compared before and after the training as secondary outcome measures. The second aim of this study was to determine inter-rater reliability of the results for three assessors who scored the videos of participants performing the tests.
Materials and methods
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5 min). Based on the previous recommendations, a staged approach was followed for both groups (Appendix) (Koumantakis, Watson, and Oldham, 2005). This approach contained eight exercise levels of progressively increasing difficulty. In the first session, the exercises were explained and demonstrated to the participants. Core stability exercise In the CSE group, anatomy and function of local back stabilizing muscles and the way they could be activated were taught. The first four sessions were on local muscle contraction recognition. Then, low-load activation of these muscles was administered isometrically in minimally loading positions. Progressively, integration with dynamic function (activities that required spinal or limb movements) through incorporation of co-contraction of the stabilizing muscles into light functional tasks was included (Appendix). Heavier-load functional tasks with exercises similar to those performed by the participants in the TTE group were progressively introduced in the last six sessions of the program. To ensure correct activation of the transversus abdominis muscle, it was emphasized to the participants that the lower part of the anterior abdominal wall below the umbilical level needed to be ‘‘drawn in’’ with the action of this muscle. Also, bulging action of the multifidus muscle needed to be felt under the therapist’s fingers when they were placed on either side of the spinous processes of lumbar vertebrae, directly over the belly of this muscle (Richardson, Hodges, and Hides, 2004).
Study design The study design was a quasi-randomized controlled trial. Approval for the research was obtained from the ethics committee of Tehran University of Medical Sciences (TUMS). Participants As we used a new rating method for the functional tests (Perrott, Pizzari, Opar, and Cook, 2012), no relevant standard deviation value was found for sample size calculation. We made the assumption that 20 participants would be sufficient, so the study was started with 19 people in one and 20 in the other group. For functional tests, the standard deviation of all our participants at pre-intervention assessment was 9.04. Using this value, to detect a difference between groups with confidence interval of 8.5 (27.44–35.94) for power of 80% and a significance level of 0.05, a sample of 18 was calculated to be sufficient. Inclusion criteria for participants were having LBP for more than 3 months, age of 18–60 years, and pain intensity from 3 to 6 in the VAS scale. Participants had no history of having pathology or anomaly in lower limbs such as malignancy, inflammatory diseases, severe osteoporosis, arthritis, or bone diseases. Participants were classified as having CLBP based on history, imaging, and pain provocation tests. Pain provocation tests are claimed to be the most reliable of the palpatory tests in chronic non-specific LBP diagnosis and were our main clinical test (Airaksinen et al, 2006). Accompanying history, imaging and pain provocation test findings enabled us to confirm the classification as non-specific CLBP. Participants were assigned a number in the order that they entered the study. Those with odd numbers were assigned to the core stability exercise (CSE) group and those with even numbers to the TTE group. At the time of admission, the study was explained to participants and their informed consent was obtained. Interventions Common components of the two programs included a warm-up period (eight stretching exercises and stationary bicycling for
TTE For the TTE group, exercises activating the extensor (paraspinals) and flexor (abdominals) muscle groups were used. They were performed in a lying position commencing with simple movements and progressing to more difficult exercises (e.g. on a Swiss ball) (Appendix). An attempt was made to equalize the exercise dose for each group. In each session, the participants were instructed to perform their exercises as many times as they could with rest periods in between in the same session. However, the pure exercise time for each CSE and TTE group session was set to 20 and 14 (a total of 320 and 224) min, respectively. Based on the previous studies (Danneels et al, 2001), these times were selected to balance the groups estimated total trunk muscle force output. Participants who were absent for three consecutive, or five sessions in total were excluded. Participants were blinded in the sense that they were unaware of the existence of the two groups, however, they did know the exercises they were performing. Each group performed three exercise sessions for a week, a total of 16 sessions. An experienced physiotherapist was responsible for supervising both groups to perform the exercises correctly in the defined time duration. Outcomes Lumbopelvic functional tests Three LPS functional tests: (1) SLS (Figure 1); (2) DT (Figure 2); and (3) RPT (Figure 3) were used. Before and after the 16 training sessions, videos were recorded from a distance of approximately 3 m to the participants while performing these tests. Three physiotherapists (PhD candidates) with 3–10 years of practical experience were selected to score the tests. They had not participated in the study design and were not authors of this study. Before the observation, they received written instruction and an explanation on how scoring of the tests should be performed. They were blinded to which group each patient had been assigned.
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DOI: 10.3109/09593985.2014.959144
Figure 1. Single leg squat.
Exercise for chronic low back pain patients
Figure 2. Dip test.
Rating criteria for scoring the tests were based on a previous study (Perrott, Pizzari, Opar, and Cook, 2012). Fourteen key factors were defined for the tests’ scoring (DT and SLS: five each, and RPT four factors) (Tables 1–3). Each of the key factors for the tests had descriptive performance characteristics that represented either good or poor stability (Perrott, Pizzari, Opar, and Cook, 2012). Regarding rating criteria, three assessors rated the 14 key factors as good or poor for each participant. Each good factor was recorded as one and each poor factor as zero. In order to convert from a nominal to a continuous variable, the sum of scores (good ratings) for 14 factors from all three assessors (total test score) constituted the participant’s overall test score. Disability and pain All participants completed the Persian translated version of the Oswestry Disability Questionnaire (Mousavi et al, 2006) (0 ¼ no disability, 100 ¼ totally disabled), and their pain intensity was measured by visual analogue scale (VAS) (0 ¼ no pain, 100 ¼ pain as bad as it could be) before and after training. Statistical analysis Cohen’s kappa coefficient was used to assess inter-rater reliability of the three assessors’ test results. Independent-sample t-test was used to compare disability level, pain intensity, and participant’s test scores between the two groups: first, at the start of the study to confirm equality of samples; and second, at the end of the study to assess whether or not the changes in these variables during intervention were statistically different in the two groups. Paired t-test was used to investigate whether the three variables were changed by the intervention. Effect size for each group was calculated as the difference between mean values before and after the intervention divided by the standard deviation for
Figure 3. Runner pose test.
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Table 1. Single leg squat.
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Good 1. Overall impression Smooth, good-quality movement General control Controlled change-over between repetitions Ease of movement 2. Weight transfer Minimal translation of centre of mass Upright trunk 3. Lumbar Spine & Pelvic Alignment Minimal movement in all three planes Frontal plane: ASIS level Sagittal plane: minimal A-P tilt, rotation Lateral view: stable lordosis, minimal trunk flexion 4. Leg alignment Minimal movement out of the starting plane of movement. This takes into account the alignment of the limb, influenced by pelvic width, and Q angle at the knee 5. Foot alignment Neutral foot position – remains stable during movement
Poor Staggered movement Increased speed to attempt to control movement Effort to control movement Trunk ‘‘wobble’’ Discernible translation of centre of mass Trunk leaning forward or to side Extended time to transfer Discernible movement with pelvis tilting up or down Rotating toward or away from weight bearing leg, tilting in anterior or posterior direction Lumbar lordosis increasing or trunk flexion occurring Discernible movement out of the starting plane of movement Excessive pronation of foot during squat descent Externally rotated starting position of lower leg/foot
Table 2. Dip test. Good 1. Overall Impression Smooth, good-quality movement General control Controlled change-over between repetitions 2. Weight distribution Minimal weight on back leg Back leg remains oriented in the sagittal plane (i.e. no movement in frontal plane) Upright trunk 3. Lumbar and pelvic alignment Minimal movement in all three planes Frontal plane: ASIS level Sagittal plane: minimal A-P tilt, rotation Lateral view: stable lordosis, minimal trunk flexion 4. Leg alignment Minimal movement out of the starting plane of movement. This takes into account the alignment of the limb, influenced by pelvic width, and Q angle at the knee 5. Foot alignment Neutral foot position – remains stable during movement
Poor Staggered movement Increased speed to attempt to control movement Effort to control movement Trunk ‘‘wobble’’ Excessive weigh on back leg Abduction of back leg Trunk leaning forward or to side Discernible movement with pelvis tilting up or down, Rotating toward or away from weight bearing leg, tilting in anterior or posterior direction Discernible movement out of the starting plane of movement Excessive pronation of foot during squat descent Externally rotated starting position of lower leg/foot
Table 3. Runner pose test. Good 1. Overall Impression Smooth, good-quality movement General control 2. Weight distribution Minimal translation of centre of mass 3. Pelvic alignment Hip dissociation from pelvis – minimal pelvic movement Minimal A-P movement (anterior pelvic tilt) Minimal tilt in frontal plane (ASIS level) 4. Trunk alignment No rotation of trunk Trunk upright
the data. Between group effect size was the difference between two means divided by a pooled standard deviation. Minimal important difference (MID) for test scores was defined as one half a standard deviation (Norman, Sloan, and
Poor Jerky movement Effort to control movement Excessive trunk movement Inability to maintain centre of mass over weight-bearing leg Discernible movement of pelvis with the hip – no dissociation Discernable tilt in frontal plane Trunk rotation Forward flexion of trunk Trunk locked in extension
Wyrwich, 2003). Minimal detectable change (MDC) at the 90% confidence level was calculated using the formula (Stratford, 2004): MDC ¼ 1.96 standard error of measurement square root of 2.
Exercise for chronic low back pain patients
DOI: 10.3109/09593985.2014.959144
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Results Five out of 44 participants fulfilling the inclusion criteria dropped out during the study and 39 participants remained (19 participants in CSE and 20 in TTE group). Participant characteristics are presented in Table 4. There was a difference in age between groups with the TTE cohort being significantly older (p ¼ 0.015). Mean kappa coefficient value for inter-rater assessors reliability in both pre and post-training test scores was 0.30, indicating poor agreement (Table 5). There was no statistical significant difference between the groups on entry to the trial in test scores (p ¼ 0.79), disability (p ¼ 0.74), and pain (p ¼ 0.83). Statistical analysis revealed a significant improvement in LPS test scores (p ¼ 0.02) for both the CSE and the TTE group (p ¼ 0.041) and reduction in disability level (p50.001) and pain intensity (p50.001) within each group after the intervention period (Table 6). With regard to changes in outcomes (the difference between before and after treatment values), no significant difference was seen between CSE and TTE groups in the three variables of LPS (p ¼ 0.41), disability (p ¼ 0.14), and pain (p ¼ 0.72) (Table 6). The effect size due to CSE was 0.44 for LPS test scores, 1.50 for disability, and 3.34 for pain, and the effect size due to TTE was 0.23, 1.13, and 3.20, respectively. Between group effect sizes for LPS test scores, disability, and pain were 0.04, 4.88, and 1.18 all in favor of the CSE group (Table 6). MID for test scores at pre-intervention period for both groups was 4.6, and MDC for the CSE and TTE groups was 17.6 and 15.2, respectively.
Discussion This study compared core stability exercise and TTE in patients with chronic non-specific LBP. Over the course of 16 training sessions both groups improved LPS, as well as disability and pain Table 4. Participant characteristics.
Gender: Male Female Age/mean (SD) Height (cm)/mean (SD) Weight (kg)/mean (SD)
Core stability exercise group
Traditional trunk exercise group
6 13 38.5 (11.9) 166.7 (8.6) 68.9 (15.7)
6 14 47.7 (10.4) 163.7 (8.3) 73.1 (8.9)
Table 5. Inter-rater assessors’ reliability. Raters 1 and 2
Raters 1 and 3
Raters 2 and 3
Mean
0.26 0.28
0.30 0.25
0.34 0.37
0.30 0.30
Before intervention test After intervention test
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scores indicating that both forms of exercise were beneficial. This is a good outcome for both groups of participants. There were no overall between-group effects on these outcomes. However, our small sample size may have contributed to type two error. The effects of CSE in people with CLBP have been investigated in some studies. In a meta-analysis comparing CSE and TTE for CLBP (searching papers from 1970 to 2007) (Wang et al, 2012), in five clinical trials which fulfilled the criteria for this study, CSE was better than TTE for reducing pain and disability in short-term follow-up. However, no significant differences were observed between CSE and TTE in reducing pain at 6 and 12 months. No stability outcome measures were considered in this meta-analysis. In general, our results were consistent with the findings of the meta-analysis. However, some studies have shown better outcomes from CSE in comparison with TTE (Ferreira et al, 2007; O’Sullivan, Phyty, Twomey, and Allison, 1997). Stability of the spine is provided by the integrated relationship of three sub-systems: (1) active, (2) passive, and (3) control (Panjabi, 1992). While the function of each of these subsystems can be weakened through injury or disuse, it is hypothesized that training the active sub-system can re-establish function (Mills, Taunton, and Mills, 2005). The rationale for CSE is restoration of the ability of the neuromuscular system to control and protect the spine from injury. To achieve this, exercises are used to restore the coordination and control and also the capacity (i.e., strength and endurance) of the trunk muscles (Hodges, 2003). Although the essence of CSE is re-education of local or deep intrinsic lumbopelvic muscles, many believe that most torso muscles, and not only local ones, are important and their level of importance depends on their activity (McGill, 2001). In spite of the rationale for CSE, other authors (Koumantakis, Watson, and Oldham, 2005) believe that insignificant improvement in the CSE group outcomes versus TTE in their studies may indicate that CSE is more related to LBP patients who suffer from either gross spinal instability symptoms or pronounced sideto-side differences in the size of the multifidus muscle than to patients who do not present any signs and symptoms of clinical instability. As mentioned earlier, in spite of low reliability of visualobservation clinical tests, they can be used as a basis for clinical decision making (DiMattia et al, 2005). Intrarater reliability for the tests was not examined. One strength of the current study was the use of a total test score that most likely improved the ability to demonstrate a change in LPS that occurred rather than using a categorical rating method. This is important in clinical decision making but may have reduced the interrater reliability, as good reliability is difficult to obtain when raters are required to make fine discriminations (McHugh, 2012). Although the aim of CSE is enhancing spinal stability, insignificant differences between the two groups may indicate either non-specificity of CSE to increase lumbopelvic stability or
Table 6. Means, standard deviations (SD), effect size, and within and between group differences for the exercise groups following the intervention period. Core stability group Outcome measures
Before
a
After
Total test score 27.8 (9.2) 31.6 (7.9) Oswestry disability 51.1 (12.7) 33.3 (11.0) Pain intensity 52.4 (9.2) 15.9 (12.4) a
Sum of three raters’ score.
p Value for difference Effect size p ¼ 0.020 p50.001 p50.001
p Value for difference p Value for Effect between Between group difference size groups effect size
Traditional trunk exercise group
0.44 1.49 3.34
Before
After
27.1 (9.1) 29.3 (9.9) 49.8 (10.8) 37.4 (11.1) 53.0 (9.2) 14.9 (14.1)
p ¼ 0.041 p50.001 p50.001
0.23 1.13 3.20
p ¼ 0.41 p ¼ 0.14 p ¼ 0.72
0.04 4.88 1.18
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equal effectiveness of TTE and CSE on improving LPS. The non-significant differences may also be attributable to the lack of sensitivity of our tests to assess stability change in two groups after training given the relatively small sample size. Core stability components including strength, endurance, flexibility, motor control, and function have already been measured in previous studies. There are many functional tests that measure these factors. In addition, the pressure biofeedback unit was developed to assess the ability of the abdominal muscles to actively stabilize the lumbar spine (Jull et al, 1993). No study was found in the literature using tests of core stability as an outcome measure in comparing the effects of CSE and TTE. It is claimed that none of the studies on CSE actually has shown a relationship between improvement in LBP and spinal stabilization or core control (Lederman, 2010). Outcome measurements in previous studies have been pain, disability, LBP episodes, and health-related quality of life (Lederman, 2010). We believe that the novelty of our study lies in trying to specifically measure LPS to judge the effectiveness of these exercises on CLBP Limitations The intervention was a prolonged process lasting about 1.5 months. It was difficult to recruit sufficient participants who met the inclusion and exclusion criteria who were willing to participate for 6 weeks. The mean age was higher in TTE (48.7) than CSE (39.3) group (p ¼ 0.015), which can be considered as a drawback of systematic sampling (alternative allocation of participants in two groups). To have a more clear insight on the impact of different exercises on LPS, it is suggested that further studies be conducted using other methods to measure LPS such as biomechanical models, other functional LPS tests, and pressure biofeedback unit to more reliably assess the impact of different exercises on LPS.
Conclusion The present results provide evidence that both types of training enhance LPS and reduce pain and disability. However, there is no evidence that one type of exercise is more effective than the other in doing so.
Acknowledgements The authors thank Iran University of Medical Sciences Physiotherapy, Ph.D. students, Mr. Mehdi Zamanlou, Mr. Mahmood Akbari, and Mr. Mohammad Reza Pourahmadi for their kind assistance in test video scoring; Dr. Ali Amiri and his colleagues in the Physiotherapy Department of Rasool Akram Hospital (Tehran, Iran) for their cooperation; Dr. Amir Hosein Hashemian for his statistical advice; and Dr. Bahman Mehraban for his grammatical correction on the manuscript.
Declaration of interest The authors report that they have no conflict of interest. This work was part of a PhD project supported by the grants from Iran University of Medical Sciences.
References Airaksinen O, Brox JL, Cedraschi C, Hildebrandt J, Klaber-Moffett J, Kovacs F, Mannion AF, Reis S, Staal JB, Ursin H, Zanoli G; COST B13 Working Group on Guidelines for Chronic Low Back Pain 2006 European guidelines for the management of chronic nonspecific low back pain. European Spine Journal 15: S192–S300. Costa LO, Maher CG, Latimer J, Hodges PW, Herbert RD, Refshauge KM, McAuley JH, Jennings MD 2009 Motor control exercise for chronic low back pain: A randomized placebo-controlled trial. Physical Therapy 89: 1275–1286. Danneels LA, Vanderstraeten GG, Cambier DC, Witvrouw EE, Bourgois J, Dankaerts W, De Cuyper HJ 2001 Effects of three
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Exercise for chronic low back pain patients
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van Tulder M, Koes B 2007 Evidence-based medicine for low back pain. In: van Goethem J, van den Hauwe L, Parizel P (eds) Spinal imaging: Diagnostic imaging of the spine and spinal cord. New York, NY, Springer Publishing Company. van Tulder M, Malmivaara A, Esmail R, Koes B 2000 Exercise therapy for low back pain: A systematic review within the framework of the Cochrane Collaboration Back Review Group. Spine 25: 2784–2796.
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Appendix Stage 1
Core Stability Group
General Exercise Group
Isolated lumbar stabilizing muscle training Classic abdominal and back extensor training Physiother Theory Pract Downloaded from informahealthcare.com by Dokuz Eylul Univ. on 11/06/14 For personal use only.
Session Development of the percepon of the isolated isometric specific contracon of the stabilizing muscles Transversus abdominis muscle from: 4-point kneeling and lying posions, trying to hollow the lower abdomen
1-2
Mulfidus muscle from: stepping acvity while standing and raising contralateral arm, trying to feel the contracon of the opposite-side mulfidus muscle or from sing posion with therapist’s hands over the muscle
Precise repeon of the isolated isometricspecific co-contracon of the stabilizing muscles, increasing their contracon me Transversus abdominis and mulfidus muscles together from: sing and standing posions
3-4
7
Upper and oblique abdominals from lying posion: with Knees straight (hands filling space between low back and exercise mat) and knees bent
Back extensors: liing trunk to neutral from prone posion with pillow under stomach and arms by the side Coordinaon: pelvic lng from lying, sing, and standing posions
Upper and oblique abdominals from lying posion: with knees straight, knees bent Back extensors: liing trunk to neutral from prone posion with pillow under stomach and arms by the side Exercises performed as illustrated for sessions 1 and 2
8
M. B. Shamsi et al.
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Stage 2
Core Stability Group Session
General Exercise Group
Integraon of lumbar stabilizing muscle Classic abdominal and back extensor training acvity into light dynamic funconal tasks Control of neutral lumbopelvic postures Isolated movement of adjacent body areas, maintaining lumbar spine stability (ie, moving only hip or thoracic spine)
Abdominals from lying posion: heel slides, lower abdominal crunches
Control of neutral lumbopelvic postures and aggravang postures
Abdominals from lying: heel slides, leg slides, lower abdominal crunches
Stabilizing muscle isometric co-contracons with addion of external load to lumbar spine
Back extensors: bridging, liing trunk to neutral( prone posion with arms elevated), single-leg extensions from prone and 4-point kneeling posions
Back extensors: bridging, liing trunk to neutral from prone posion and arms in elevaon
Physiother Theory Pract Downloaded from informahealthcare.com by Dokuz Eylul Univ. on 11/06/14 For personal use only.
5-6
Hip horizontal abducon, heel slides, leg slides from crook-lying posion
7-8 Aggravang postures
Lumbopelvic control during movements and aggravang movements Sing on unstable base of support (hip extension movement only, lumbar spine only, thoracic only), 3-plane movement, cocontracons during normal-speed walking and other acvies
9-10
Abdominals from lying posion: straight leg lis toward ceiling, cycling exercises, leg slides, lower abdominal crunches Obliques: hip li from side-lying posion Back extensors: as in sessions 7-8
Exercise for chronic low back pain patients
DOI: 10.3109/09593985.2014.959144
Stage 3
Core Stability Group Session
General Exercise Group
Integration of lumbar stabilizing muscle Classic abdominal and back extensor training activity into heavy-load dynamic functional tasks Isometric co-contracons with addion of heavier external loads to lumbar spine Bridging exercise, co-contracons during leg cycling from supine posion, single-leg extensions from 4-point kneeling posion
Abdominals from lying posion: full abdominal crunches, straight leg lis toward ceiling, cycling exercises, leg slides Obliques: hip li from side-lying posion
Physiother Theory Pract Downloaded from informahealthcare.com by Dokuz Eylul Univ. on 11/06/14 For personal use only.
Back extensors: alternate arm/leg extensions from 4point kneeling and lying posions, single-leg bridging Swiss ball coordinaon exercises: alternate arm/leg lis sing on ball
11-12
Increasing complexity and load of exercises maintaining lumbar spine stability Single-leg bridging exercise, bridging exercise with an unstable base of support
13-14
Alternate arms/leg extensions from 4-point kneeling and lying posions and arm/leg lis sing on Swiss ball Funconal co-contracons during walking (increasing speed) and other acvies
Abdominals from lying posion: same leg and arm liing-lowering, full abdominal crunches, straight leg lis toward ceiling, cycling exercises, leg slides Obliques: advanced hip li from side-lying posion Back extensors: as in sessions 11-12 Swiss ball coordinaon exercises: abdominal curls on ball from prone posion, pulling legs toward chest
9
10
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Physiother Theory Pract, Early Online: 1–10
13-14
Physiother Theory Pract Downloaded from informahealthcare.com by Dokuz Eylul Univ. on 11/06/14 For personal use only.
Coordinaon exercises Single-leg bridging exercise with an unstable base of support, bridging exercise with rotator self-resistance, simultaneous arm and leg movements from supine posion maintaining lumbar spine stability, funconal cocontracons during walking (changing speeds) and other acvies
Abdominals from lying posion: same leg and arm liing-lowering, cycling exercises Obliques: full oblique abdominal crunches, li from side-lying posion Back extensors: as in sessions 11-12 Swiss ball co-ordinaon exercises: oblique abdominal curls on ball from prone posion, single-leg bridging
15-16
This appendix is a modificaon of the appendix of Koumantakis GA et al 2005 arcle.
