THE EFFECT OF CORE STABILITY EXERCISES ON VARIATIONS DISABILITY DURING AN EPISODE OF ACUTE NONSPECIFIC LOW BACK PAIN: APILOT CLINICAL TRIAL

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1 THE EFFECT OF CORE STABILITY EXERCISES ON VARIATIONS IN ACCELERATION OF TRUNK MOVEMENT, PAIN, AND DISABILITY DURING AN EPISODE OF ACUTE NONSPECIFIC LOW BACK PAIN: APILOT CLINICAL TRIAL Augustine Aluko, PhD, a Lorraine DeSouza, PhD, b and Janet Peacock, PhD c ABSTRACT Objective: The purpose of this preliminary study was demonstrate if it was feasible to evaluate variations in acceleration of trunk movement, pain, and disability during an episode of acute nonspecific low back pain comparing regular trunk exercises to regular exercises in addition to core stability exercises. Methods: A pilot randomized controlled trial was used to evaluate 33 participants recruited from a National Health Service physiotherapy musculoskeletal provider in the London district of Hillingdon. Participants were allocated to 2 groups; a regular exercise group (male, 2; female, 15) with a mean (SD) age of 35.8 (9.1) years and intervention group (male, 3; female, 13) with a mean (SD) age of 36.2 (9.8) years. The regular exercise group received exercise that consisted of a core stability class including both specific and global trunk exercises. The intervention group, in addition to these core exercises, received further instruction on 8 specific stabilization muscles involving the transversus abdominis and the lumbar multifidus. Trunk sagittal acceleration, pain, and disability were measured using a Lumbar Motion Monitor, pain visual analog scale, and Roland Morris Disability Questionnaire, respectively. Measures were taken at baseline, 3 and 6 weeks, and a 3-month follow-up. Multiple regression with adjustment for baseline value was used to analyze each outcome. All outcomes were log transformed to correct skewness and so presented as ratio of geometric means with 95% confidence interval. Results: Differences in mean trunk sagittal acceleration between the regular exercise and intervention groups was not statistically significant at any time point (ratio of means [95% confidence interval]: 3 weeks 1.2 [ ], P =.2; 6 weeks 1.1 [ ], P =.7; 3 months: 1.2 [ ], P =.9). Similarly, the effects on neither pain score nor disability score were significant (pain score: 3 weeks 1.3 [ ], P =.3); 6 weeks 1.2 [ ], P =.6; 3 months 1.0 [ ], P = 1.0); disability score: 6 weeks 1.0 [ ], P = 1.0; 3 months 1.3 [ ], P =.3). Outcome measures for both groups improved over time. Conclusions: This pilot study demonstrated that a study of this nature is feasible. Both the regular exercise and the intervention groups demonstrated improvements in mean trunk sagittal acceleration at 3, 6, and 12 weeks. The preliminary findings showed that evidence was inconclusive for the beneficial effect of adding specific core stability exercises for acute low back pain. The results of this study demonstrated an increase in acceleration accompanied by a reduction in pain, which may suggest that acute nonspecific low back pain may induce the pain-spasm-pain model rather than the pain adaptation model. (J Manipulative Physiol Ther 2013;36: e3) Key Indexing Terms: Low Back Pain; Exercise; Biomechanics a Lecturer in Physiotherapy, Centre for Research and Rehabilitation, School of Sciences and Social Care, Brunel University, London, UK. b Head of School and Professor of Rehabilitation, Centre for Research and Rehabilitation, School of Sciences and Social Care, Brunel University, London, UK. c Professor of Medical Statistics, Department of Primary Care and Public Health Sciences, Kings College London, London, UK. Submit requests for reprints to: Augustine Aluko, PhD, Lecturer in Physiotherapy, Timberdown Ecchinswell, Nr Newbury, Berkshire RG20 4UH, UK ( toks@askaphysio.com). Paper submitted July 2, 2012; in revised form December 11, 2012; accepted December 27, /$36.00 Copyright 2013 by National University of Health Sciences

2 498 Aluko et al Journal of Manipulative and Physiological Therapeutics October 2013 The core of the torso is described as the lumbopelvic region, and it has been suggested that exercises to facilitate integrity within musculature in this area improve spinal segment stability. 1,2 However, there is no clinically recognized definition of core stability exercises (CSEs) and therefore no standardized recommendation for any specific grouping of exercises. 3 The belief systems that underpin the current use of CSEs as a treatment of conditions such as nonspecific mechanical low back pain (NSLBP) suggests that focus should be on the lumbar multifidus and transversus abdominus muscles. 4 Indeed, depending on the frequency of the exercises an increase in the cross-sectional area of the lumbar multifidus as a direct result of CSE can be demonstrated within 6 weeks. 5 Earlier work suggests that NSLBP is correlated to poor lumbar segment stability, 6 and thus, CSEs have become a popular choice of intervention for its treatment. 1,2 Core stability exercises are said to assist in the activation of the deep fibers of the lumbar multifidus through low loaded isometric activity. 4,3 However, their overall effectiveness remains uncertain. 7,8 The effectiveness of CSEs in the management of chronic NSLBP is ambiguous because the effects may not be more than that of other methods of management involving activity. 8 However, there is paucity of literature to evaluate its effect during an acute episode of NSLBP. This may be because it is assumed that the effects of stabilization exercises in enhancing neuromuscular control and rectifying dysfunction 9-11 may not be required during an acute phase of low back pain (LBP). This assertion is further compounded by the belief that most episodes of LBP resolve within 3 months in 90% of cases 12 and persistent back pain will resolve by the sixth week after onset. 13,14 However, there is increasing evidence to suggest that although NSLBP as a symptom may resolve, there may remain unresolved biomechanical indicators for poor lumbar function, 15,16 which may result in further lumbar instability. It is purported that CSEs have an influence on these indicators. A recent systematic review of stabilization exercises as an intervention for LBP 8 based the findings on outcomes mainly associated with measures of either pain or disability. The tools used were the visual analog scale (VAS) or McGill pain questionnaire and questionnaires such as the Oswestry Disability Index or Roland Morris Disability Questionnaire (RMDQ), respectively. The VAS is reliable and valid as an outcome measure, 17 especially with LBP 18 ; however, the reliability of the score depends on the rigor of the protocol to ensure that recall bias 19 is minimized. Furthermore, the RMDQ is regarded to be the preferable measure of disability 20,21 and is both valid and reliable. 22 In contrast, the Oswestry Disability Index has low internal consistency (Cronbach α =.77) containing a mixture of both capacity and performance based items. 23 Low back pain can be quantified using instantaneous objective measures using a Lumbar Motion Monitor (LMM) 24 to evaluate 3-dimensional spinal kinematics It is therefore possible to use a similar protocol as that used within the aforementioned studies to evaluate the effectiveness of CSEs minimizing the reliance upon other measures. Therefore, this preliminary study aimed to quantify the effect of CSEs on trunk sagittal acceleration during an episode of acute NSLBP and offer an insight to how stabilization exercises may influence trunk functional movement. METHODS This study was a randomized controlled trial and received ethical approval from the School of Health Sciences and Social Care Ethics committee, Brunel University, London, UK, and the Oxfordshire NREC ethics committee (Reference No. 07/H0606/102). The participants (n = 33) were recruited between July 2008 and June 2010 from within a primary care musculoskeletal physiotherapy service provider within the London Borough of Hillingdon. This unit provided a central base of treatment for patients across the Borough who were referred by their general practitioners. All participants gave informed consent to participate in the study. The study was for a 6-week period with a 3-month follow-up. Participants were excluded if they demonstrated evidence of any of the following: degenerative conditions affecting the spine, 29 diabetes, 30 pregnancy, 31 underlying neurologic conditions, 32 active treatment of an ongoing spinal condition, 33 active legal/compensation procedures, 34 having a history of depression, 34 having a history of multiple recurrent episodes of LBP, 34 and involvement in other research studies. 35 Participants who did not have English as their primary language were also excluded. The participants were randomly allocated to either a routine care (n = 17) or an intervention (n = 16) group (Table 1). The randomization was done by a colleague independent and blind to the study using concealed envelopes within which the group description was randomly placed within them. The envelopes were numbered sequentially and chosen by the participants in the order in which they were recruited. All participants were referred for treatment of an onset of acute NSLPB (anslbp) with a maximum duration of 6 weeks. Twenty-two (67%) had a previous episode of anslbp. The onset of the symptoms varied within the participants; 6 participants described the onset of their symptoms as being sudden, 25 gradual, and 2 insidious. All patients referred for treatment of anslbp within physiotherapy service providers were assessed and subsequently offered a place in a core stability class consisting of both specific and global trunk exercises (Appendix 1).

3 Journal of Manipulative and Physiological Therapeutics Volume 36, Number 8 Aluko et al 499 Table 1. Study group descriptive Regular exercise group (male, 2; female, 15) Intervention (male, 3; female, 13) Age (y), mean (SD) Height (cm), mean (SD) Weight (kg), mean (SD) 35.8 (9.1) (9.0) 73.3 (15.6) 36.2 (9.8) (10.6) 75.9 (18.0) Participants in both groups received this protocol as minimum intervention. The intervention group received further instruction on 8 specific stabilization muscle involving the transversus abdominis (TrA) and the lumbar multifidus (LM). Equipment The LMM was used to evaluate trunk sagittal acceleration. The LMM has been demonstrated to be a valid and reliable 36 tool for trunk sagittal acceleration evaluation. The reliability was repeated for a single measure (intra-class correlation coefficient, 0.96; 95% confidence interval [CI], ), 16 and laboratory calibration tests of the LMM have demonstrated only a 2% discrepancy between actual measurement and recorded data. 37 Core Stability Exercises There is no formal definition of CSEs or recommendation for any specific grouping of CSEs. 3 There is also no justification for the choice, combination of, or the number of repetitions and frequency of the chosen exercises. 3 The selection of exercises used in this study therefore relied on current belief systems suggesting that the isolation of the TrA and LM is important for trunk stability 4 (Appendix 2). These exercises were as follows: abdominal hollowing in prone lying, alternate straight-leg raise in supine, abdominal hollowing in sitting, Crook lying alternate heel slide, 4-point kneeling pelvic shift (side to side), trunk curl in crook lying, pelvic tilt in sitting, and alternate knee raise in sitting. The exercises met suggested criteria for safety; these included the avoidance of active hip flexion with fixed feet positioning and pulling with the hands behind the head and ensuring knee and hip flexion during all upper body exercises. 38 The intervention group participants were required to perform 10 repetitions of each of the above exercises 3 times a day. To facilitate compliance, participants were required to complete a compliance diary. The diary method was chosen to avoid adding to the participants' perceived barrier to exercise by impinging on the available time that they have to do the exercise routine. 39 Protocol Initial evaluation of outcome measures of trunk sagittal acceleration ( /s 2 ) using the LMM, pain (mm) using a VAS comprising of a 100-mm line with no numbers, and disability using the RMDQ was taken at the start of the study and at 3, 6, and 12 weeks subsequently (Fig 1). Data were collected by the researcher who was therefore not blinded to the grouping of any of the participants. At the initial visit, those allocated to the intervention group were given an individual initial specific CSE instruction by the researcher and a diary large enough to contain only 3 weeks' entry data. This ensured that the participants within this group would have to request more sheets to complete the following 3 weeks. At time point, the participants in the intervention group were asked to demonstrate the exercises to ensure that they had mastered the routine. Care was taken to ensure that each participant felt that he/she was given equal access to the researcher throughout the study. The standard LMM protocols for a 5-task evaluation 27 and a single-task evaluation 29 have been adequately described elsewhere. This study used the single-task evaluation method. The LMM protocol required the participants to perform as many sagittal trunk flexion-extension movements as possible for 8 seconds. The movement was executed at the participants' preferred speed and within their preferred range of movement. It has been demonstrated that experimental pain can alter neuromuscular responses during a trunk flexion-extension task. 40 No encouragement verbal, nonverbal, or otherwise was offered. Although LBP increases the time for trunk muscles to reach peak force during a contraction, 41 no warm-up exercise was performed because the interest of the study lay within the natural muscle recruitment process to effect functional movement without prior warning. All trunk measurements were therefore also taken before each scheduled core stability class. All participants completed the evaluation, and none reported an exacerbation of their symptoms. The RMDQ score was not obtained at 3 weeks. Statistics In the absence of a known published clinically significant difference for the primary outcome measure of mean trunk sagittal acceleration resulting from CSEs, it was not possible to use a standardized calculation to determine an appropriate sample size. The sample size was therefore derived from a similar study previously published. 42 Although the participants were randomly allocated as they were recruited and blinded to the study, it was not possible to blind the assessment process. Analysis The outcome data were analyzed using multiple regression analysis where the baseline value was included as a covariate for each analysis. Because all outcomes were

4 500 Aluko et al Journal of Manipulative and Physiological Therapeutics October 2013 Fig 1. Study flow diagram. LMM, Lumbar Motion Monitor; RMDQ, Roland Morris Disability Questionnaire; VAS, visual analog scale. skew, data were log transformed, and therefore, results are presented as the ratio geometric means with 95% CI. These are interpreted as showing the percentage difference in mean value between the 2 groups; for example, a ratio of 1.20 for the intervention/regular exercise group indicates that the intervention group was on average 20% greater than the regular exercise group. An intention-to-treat analysis 43 was used with missing data replaced with the Last Observation Carried Forward 44 for incomplete data sets. This process was deemed appropriate for this study because the trend of the raw data demonstrated either a sequential improvement or status quo in the outcome measures within both groups of participants. All data analyses were conducted using SPSS (V. 15; SPSS, Chicago, IL). RESULTS Data were collected from both the regular exercise group, which had a mean (SD) age of 35.8 (9.1) years, with a mean (SD) height of (9.0) cm and a mean (SD) weight of 73.3 (15.6) kg, and the intervention group, which had a mean (SD) age of 36.2 (9.8) years with a mean (SD) height of (10.6) cm and mean (SD) weight of 75.9 (18.0) kg (Table 1). The data required logarithm transformation and further analysis by regression to determine differences between the groups (Table 2). Within 3 weeks, improvement in mean trunk sagittal acceleration in the intervention group was 20% greater than in the regular exercise group, after adjusting for baseline, but this was not statistically significant (95% CI, ; P =.2) (Table 2). Similar improvements of 10% and 20%, respectively, could be seen at 6 weeks (95% CI, ; P =.7) and 3 months (95% CI, ; P =.9). These results were not statistically significant (Table 2). Mean pain scores were similar in both groups at each stage of the study; the differences in mean pain scores between the groups adjusted for baseline were not statistically significant at 3 weeks (30%; 95% CI, ; P =.3), 6 weeks (20%; 95% CI, ; P =.6), or 3 months (0%; 95% CI, ; P = 1.0) (Table 2). Mean pain score analysis between 3 months and 6 weeks was not possible because of the effect of missing data and the small sample size. The differences in disability scores between the groups adjusted for baseline were also statistically nonsignificant

5 Journal of Manipulative and Physiological Therapeutics Volume 36, Number 8 Aluko et al 501 Table 2. Results by outcome measure Disability, mean (SD) (RMDQ 0-24) Pain score (mm), mean (SD) (VAS 1-100) Sagittal acceleration ( /s 2 ), mean (SD) P Intervention (n = 16) Regular exercise (n = 17) P Intervention (n = 16) Regular exercise (n = 17) P Intervention (n = 16) Regular exercise (n = 17) Baseline (110.2) (133.7) 31.4 (22.0) 36.4 (23.2) 10.5 (5.0) 8.6 (5.0) Analysis 3 wk (95.5) (163.4) 25.3 (23.5) 26.0 (22.0) Difference between groups adjusted 1.2 ( ) ( ).3 for baseline at 3 wk. Ratio of geometric means (95% CI) 6 wk (99.1) (178.0) 26.7 (26.0) 31.8 (23.6) 9.4 (5.8) 7.4 (5.4) Difference between groups adjusted 1.1 ( ) ( ) ( ) 1.0 for baseline at 6 wk. Ratio of geometric means (95% CI) 3 mo (99.5) (177.5) 27.1 (26.7) 25.9 (23.2) 8.4 (6.2) 6.8 (5.1) 1.2 ( ) ( ) ( ).3 Difference between groups adjusted for baseline at 3 mo. Ratio of geometric means (95% CI) RMDQ, Roland Morris Disability Questionnaire; VAS, visual analog scale. at 6 weeks (0%; 95% CI, ; P = 1.0) and 3 months (30%; 95% CI, ; P =.3) (Table 2). DISCUSSION Both the regular exercise and the intervention groups demonstrated improvements in mean trunk sagittal acceleration of 2.8% and 29.2%, respectively, at 3 weeks; 15.1% and 29.4%, respectively, at 6 weeks; and 13% and 37%, respectively, at 12 weeks. The increase in cross-sectional area of the TrA and LM shown to increase within a 6-week period 5 may therefore be directly related to improvement in mean trunk sagittal acceleration. Although the results suggest that the improvement demonstrated is not statistically significant, this size of effect is of clinical significance and so, if shown to be conclusively true, would be important. Low back pain impedes trunk acceleration 15,16 ; early intervention may therefore be productive in influencing the natural course of anslbp. The improvement in mean sagittal acceleration was maintained within the intervention group at 12 weeks, suggesting that CSE may not only improve trunk sagittal acceleration but also help to maintain it. This would have considerable clinical significance if CSEs were conclusively shown to have an integral role in reducing the risk of anslbp becoming chronic. Good posture is an important factor in managing, preventing, or facilitating recovery from an episode of LBP. However, the actual detail of the mechanics of posture is largely ignored. The range of lumbar lordosis 45 plays an important role in this because it alters according to posture. 46,47 The range of lumbar lordosis is suggested to be directly proportional to the changes in acceleration. 45 Thus, improved acceleration will increase the available range by which the lumbar lordosis is able to accommodate axial compressive forces. These results suggest that CSEs may be able to facilitate this mechanism. However, this would not be true if there was structural trunk stiffness caused by underlying natural pathology such as natural degenerative change. 48,3 It is these underlying natural pathologies that may have influenced the results of previous studies and subsequent systematic reviews to evaluate the effectiveness of stabilization exercises. This study did not demonstrate a causal relationship between the improvement in trunk sagittal acceleration and pain, although a negative correlation between pain and trunk performance has been previously reported. 45 It has been suggested that the pain adaptation model reduces trunk velocity 49 ; however, this study demonstrates an increase. The findings of this study therefore suggest that an NSLBP may induce the pain-spasm-pain model 50 rather than the pain adaptation model because the results of this study demonstrate an increase in acceleration accompanied by a reduction in pain. 50 Clinically, this could be very

6 502 Aluko et al Journal of Manipulative and Physiological Therapeutics October 2013 important because treatment/intervention for anslbp could be more effective if it is aimed at reducing the excitability of the α-neurons or reducing muscle spindle activity. 51 It is possible that CSEs are able to do this efficiently. The sensitivity of the RMDQ in quantifying disability may not be as high for the participants within this study because they were not back pain disabled ; they did not have the pain long enough to decide that certain movements caused pain unlike individuals with chronic LBP. 52 The difference in disability between the groups was neither statistically nor clinically significant because the difference was less than 30%. 53 However, the regular exercise group appeared to maintain a higher mean disability score than the intervention group. This does suggest that CSEs may facilitate a reduction in disability, albeit the depth of this facilitation is not categorical. The trend of the results was not in keeping with 2 previous studies that demonstrated significant improvement in disability after intervention at 6 weeks (50%) and at 3- month (67%) and 12-month (56%) follow-up periods. 54 Another study demonstrated a 43.2% improvement after 4 weeks. 55 It may be that the rigor applied to this study influenced the result, but this must be put in context of the smaller sample size. LIMITATIONS AND FUTURE RESEARCH The small sample size was a limitation. Also, all participants were from a wide area within the Borough, but the participants may not have been a true reflection of anslbp prevalence in the district or London in general. Further limitations include the inability to remove all possible sources of bias; the researcher not only collected the data and did the analysis but also administered the first CSE instruction. Furthermore, the study only evaluated 1 plane of trunk movement, whereas functional trunk movement is 3 dimensional. 25 There were also limitations in that there was no indication for how long a rest period should be between exercises and how the exercise routine should be distributed through the day. Also, both groups received therapeutic exercise; thus, it may be difficult to separate the effects of these 2 therapies or the additive effect of the CSE to regular therapeutic exercises. At present, it is not possible to propose a difference in trunk sagittal acceleration below which an episode of anslbp may develop. If possible such information would be useful. Further work to investigate the changes in trunk performance over time will also be beneficial. This information will be useful in identifying the cohort of individuals who may therefore benefit from early intervention of CSEs as a preventative measure. The implications of which may be significant for the cost of health care delivery. The Swiss ball is an effective rehabilitative tool for patients with LBP. 56 Further work to evaluate CSEs using this rehabilitative method may provide a greater depth of evaluation of this approach and provide greater understanding of trunk response to perturbation during an episode of anslbp. CONCLUSION Trunk sagittal acceleration appears to be sensitive to an onset of anslbp. The clinically meaningful sizes of effect were observed, which, if shown to be real in a larger study, would be important. This requires further investigation, although improvement in trunk sagittal acceleration and thus its performance was not conclusively demonstrated. Similarly, although reduction in disability and pain as a result of CSEs as an intervention may not be statistically significant between groups, the sizes of effect observed were clinically significant. Practical Applications Both the regular exercise and intervention groups demonstrated improvements in mean trunk sagittal acceleration at 3, 6, and 12 weeks. The results of this study demonstrated an increase in acceleration accompanied by a reduction in pain, which may suggest that anslbp may induce the pain-spasm-pain model rather than the pain adaptation model. FUNDING SOURCES AND POTENTIAL CONFLICTS OF INTEREST No funding sources or conflicts of interest were reported for this study. REFERENCES 1. Willardson JM. Core stability training for healthy athletes: a different paradigm for fitness professionals. Strength Cond J 2007;29: Willardson JM. Core stability training: applications to sports conditioning programs. J Strength Cond Res 2007;21: Standaert CJ, Weinstein SM, Rumpeltes J. Evidence-informed management of chronic low back pain with lumbar stabilization exercises. Spine J 2008;8: MacDonald DA, Moseley GL, Hodges PW. The lumbar multifidus: does the evidence support clinical beliefs. Man Ther 2006;11: Sokunbi O, Watt P, Moore A. A randomized controlled trial (RCT) on the effects of frequency of application of spinal stabilization exercises on multifidus cross sectional area

7 Journal of Manipulative and Physiological Therapeutics Volume 36, Number 8 Aluko et al 503 (MFCSA) in participants with chronic low back pain. Physiother Singapore 2008;11: Panjabi MM. Lumbar spine instability: a biochemical challenge. Curr Orthop 1994;8: Standaert CJ, Herring SA. Expert opinion and controversies in musculoskeletal and sports medicine: core stabilization as a treatment for low back pain. Arch Phys Med Rehabil 2007; 88: May S, Johnson R. Stabilisation exercises for low back pain: a systematic review. Physiotherapy 2008;94: Richardson C, Jull G, Hodges P, Hides J. Therapeutic exercises for spinal segmental stabilisation in low back pain. Edinburgh: Churchill Livinstone; Norris CM. Back stability. Champaign: Human Kinetics; Mcgill S. Low back disorders. Evidence-based prevention and rehabilitation. Champaign: Human Kinetics; Croft PR, Macfarlane GJ, Papageorgiou AC, Thomas E, Silman AJ. Outcome of low back pain in general practice. Br MedJ 1998;316: Jayson MIV. 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8 504 Aluko et al Journal of Manipulative and Physiological Therapeutics October Johansson H, Sojka P. Pathophysiological mechanisms involved in genesis and spread of muscular tension in occupational muscle pain and in chronic musculoskeletal pain syndromes: a hypothesis. Med Hypotheses 1991;35: Beurskens AJHM, De Vet HCW, Kök AJA. Responsiveness of functional status in low back pain: a comparison of different instruments. Pain 1996;65: Jordan K, Dunn KM, Lewis M, Croft P. A minimal clinically important difference was derived for the Roland-Morris Disability Questionnaire for low back pain. J Clin Epidemiol 2006;59: Rasmussen-Barr E, Nilsson-Wikmar L, Arvidsson I. Stabilizing training compared with manual treatment in sub-acute and chronic low-back pain. Man Ther 2003;8: Brennan GP, Fritz JM, Hunter SJ, Thackeray A, Erhard RE. Identifying subgroups of patients with acute/subacute nonspecific low back pain. Results of a randomised clinical trial. Spine 2006;31: Marshall PW, Murphy BA. Evaluation of functional and neuromuscular changes after exercise rehabilitation for low back pain using a Swiss ball: a pilot study. J Manipulative Physiol Ther 2006;29:

9 Journal of Manipulative and Physiological Therapeutics Volume 36, Number x Aluko et al 504.e1 APPENDIX 1. REGULAR EXERCISE GROUP EXERCISES Reprinted by permission from Norris CM. Back stability. CD-ROM, release 1.0. Champaign, IL: Human Kinetics; Human Kinetics, 1607 North Market Street, PO Box 5076, Champaign, IL ; pages 85 (abdominal hollowing sitting and abdominal hollowing lying), 110 (straight leg raise), 126 (trunk curl), 157 (pelvic tilt reeducation, sitting), 170 (heel slide), 174 (4-point pelvic shift), and 183 (sitting knee raise).

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11 Journal of Manipulative and Physiological Therapeutics Volume 36, Number 8 Aluko et al 504.e3 APPENDIX 2. INTERVENTION GROUP EXERCISES: CSES Reprinted with permission from PhysioTools Ltd. Viinikankatu 1 C, FIN Tampere, Finland.