Abstract
Background The effectiveness of Pilates exercise for treating people with chronic low back pain (CLBP) is yet to be established. Understanding how to identify people with CLBP who may benefit, or not benefit, from Pilates exercise and the benefits and risks of Pilates exercise will assist in trial design.
Objectives The purpose of this study was to establish a consensus regarding the indications, contraindications, and precautions of Pilates exercise and the potential benefits and risks of Pilates exercise for people with CLBP.
Methods A panel of 30 Australian physical therapists experienced in the use of Pilates exercise were surveyed using the Delphi technique. Three electronic questionnaires were used to collect participant opinions. Answers to open-ended questions were analyzed thematically, combined with research findings, and translated into statements about Pilates exercise. Participants then rated their level of agreement with statements using a 6-point Likert scale. Consensus was achieved when 70% of panel members agreed or disagreed with an item.
Results Thirty physical therapists completed the 3 questionnaires. Consensus was reached on 100% of items related to the benefits, indications, and precautions of Pilates exercise, on 50% of items related to risks, and on 56% of items related to contraindications. Participants agreed that people who have poor body awareness and maladaptive movement patterns may benefit from Pilates exercise, whereas those with pre-eclampsia, unstable spondylolisthesis, or a fracture may not benefit. Participants also agreed that Pilates exercise may improve functional ability, movement confidence, body awareness, posture, and movement control.
Limitations The findings reflect the opinions of only 30 Australian physical therapists and not all health professionals nationally or internationally. These findings, therefore, need to be verified in future research trials.
Conclusions These findings contribute to a better understanding of the indications, contraindications, and precautions of Pilates exercise and the benefits and risks of Pilates exercise for people with CLBP. This information can assist in design of future trials examining the effectiveness of Pilates exercise.
Chronic low back pain (CLBP) is common, affecting approximately 23% of people in their lifetime.1–3 This condition leads to significant disability and is associated with a large socioeconomic burden.3–5 A common treatment intervention for people with CLBP is Pilates exercise.6–8 Pilates exercise is a mind-body intervention that focuses on core stability, posture, flexibility, strength, breathing, and movement control.6
Despite its popularity, the effectiveness of Pilates exercise in people with CLBP is debated in the literature.8 Conflicting research findings may be explained by the small number and variable methodological quality of research trials and the variation in the application of Pilates exercise in treating people with CLBP.8,9 Alternatively, different results may be due to the heterogeneity of people with CLBP, where some people may respond favorably to Pilates exercise and others may not.8,9
To our knowledge, there is only one published study that has explored how to identify people with CLBP who may benefit from Pilates exercise.10 A clinical prediction rule was proposed where if people with CLBP had pain for less than 6 months, reduced trunk mobility, a body mass index of 25 kg·m2 or greater, no leg pain, or moderately mobile hips, they were likely to benefit from Pilates exercise. These results, however, were developed from review of results in a case series and require validation in randomized controlled trials (RCTs).11
When considering whether to use Pilates exercise to treat people with CLBP, it is important to review its potential benefits and risks.12,13 Although its efficacy is yet to be confirmed, some RCTs have suggested that Pilates exercise may reduce pain and disability in people with CLBP and may improve their physical and psychosocial functioning and their general health.14–17 It is unknown, however, whether these outcomes encompass all of the potential benefits of Pilates exercise.
Meanwhile, there is little mention of risks of harm with Pilates exercise in the literature. Reported ill-effects of Pilates exercise include single cases of diaphragmatic rupture, cervical disk herniation, and dislodgement of a breast implant.18–20 None of these adverse events, however, occurred in people with CLBP.
Given the dearth of literature available, a Delphi survey was undertaken to develop expert consensus regarding the indications, contraindications, and precautions of Pilates exercise for people with CLBP and the potential benefits and risks of Pilates exercise. This Delphi survey may provide direction for future research evaluating the efficacy of Pilates exercise. Survey findings also may provide interim guidelines for clinical practice, although opinions will require validation with RCTs.
Method
Design Overview
A Delphi survey was used to establish consensus opinion among 30 Australian physical therapists who were experienced in using Pilates exercise to treat people with CLBP. A series of electronic questionnaires were used to collect participant opinions. Consensus was defined as when 70% of the participants agreed or disagreed with an item. The strength of agreement or disagreement was evaluated through grading of responses with a Likert response scale.21–23
Ethics and Recruitment
Participants were recruited via purposive and snowball sampling to ensure multiple, informed opinions were sought.21,24 Potential participants were e-mailed an invitation to participate, project information, and screening and informed consent forms. To participate, physical therapists returned completed screening and consent forms to the primary researcher (C.W.), who verified information and confirmed recruitment.
Potential participants were identified through review of online, publicly available lists of physical therapists who had completed Pilates instructor training with Dance Medicine Australia Clinical Pilates or Polestar Pilates.25,26 Physical therapists who provided these instructor training courses for physical therapists in Pilates exercise also were invited to participate, along with those who reported a special interest in Pilates in the Australian Physiotherapy Association online directory.27 Potential participants also were invited to nominate interested colleagues and forward project information to them.
Selection Criteria
To be included in the study, participants needed to:
Be registered with the Physiotherapy Board of Australia to currently practice as a physical therapist without restrictions in Australia. The decision to include only registered physical therapists in Australia was to guarantee similar standards of practice of participants, as training and standards vary internationally.28
Treat people with CLBP with Pilates exercise at least weekly or have published research on Pilates exercise and CLBP in a peer-reviewed journal. The decision to include people who were knowledgeable about and experienced in using Pilates exercise to treat people with CLBP was to increase the usefulness of responses.23,29
Be able to commit to completing at least 3 rounds of the Delphi survey over 4 months. Participants needed to be proficient in the use of the English language, be computer literate, have access to e-mail and the Internet, and be able to commit time to complete questionnaires.
Survey Process
Three electronic questionnaires were e-mailed to participants between March and July 2012. The questionnaires were set up so participants could submit responses only if they had attempted to respond to every question. Participants were asked to complete each questionnaire within 2 weeks, but 2 to 4 weeks of additional time was given to maximize response rates. Once 30 responses to a questionnaire were received, the next questionnaire was e-mailed to the participants.
Questionnaires
The first questionnaire (eAppendix 1) consisted of multiple-choice questions to collect demographic information and open-ended questions to record participant opinions. Responses to open-ended questions were summarized qualitatively using thematic analysis.30 This analysis involved 2 researchers (C.W. and A.B.) identifying and condensing themes through repeated review of responses. Consultation between the reviewers was undertaken to ensure themes were not overlooked. Themes were used to generate statements about Pilates exercise and people with CLBP. Participants then ranked their level of agreement with these statements in the second questionnaire.
The second questionnaire (eAppendix 2) was developed from consideration of identified themes of participant responses to the first questionnaire, and relevant research findings.21,30 Participants were asked to rank their level of agreement with statements about Pilates exercise and people with CLBP using a 6-point Likert response scale (“strongly agree,” “agree,” “somewhat agree,” “somewhat disagree,” “disagree,” and “strongly disagree”). Open-ended questions also were used to ensure participants could clarify or expand on their opinions.
The third questionnaire (eAppendix 3) included only questions requiring a response with the Likert response scale. New themes identified from open-ended questions in the second questionnaire were used to generate additional statements for participants to rank their level of agreement with in the third questionnaire. Questions that did not reach consensus during the second questionnaire were repeated. This procedure was in accordance with Delphi survey methods, where participants are given the opportunity to reflect and change their responses over time.21 A summary of de-identified group responses from the second questionnaire was provided to the participants.
Data Analyses
Participant information.
The number of participant responses for each questionnaire was summated and monitored for dropouts. Demographic data regarding participants were summarized using descriptive statistics.
Open-ended questions.
Responses to open-ended questions were summarized qualitatively using thematic analysis.30 The number of identified themes was noted, and the themes were used to formulate questions for subsequent questionnaires.
Likert response scale questions.
The number of responses of “strongly agree,” “agree,” or “somewhat agree” were summated and expressed as a percentage of agreement. Similarly, the number of responses of “strongly disagree,” “disagree,” or “somewhat disagree” were summated and expressed as a percentage of disagreement.
Items with and without consensus.
Items with and without consensus were identified in the final 2 questionnaires, where consensus was defined as when the percentage of agreement or disagreement for questions was 70% or greater.21,31 Monitoring of any change in consensus for repeat questions in the 2 questionnaires was undertaken to observe variation in the opinions over time.31
Strength of agreement or disagreement.
Responses on the 6-point Likert scale were translated into numerical scores to summarize the strength of agreement of participants for each item.32 A score of 1 represented “strongly agree,” a score of 2 represented “agree,” and so on until a score of 6 represented “strongly disagree.” The median score and interquartile range of responses for these questions were then calculated. The median score was chosen over the mean due to the tendency of responses to converge with a Delphi survey.31,32 Items where the median score indicated that participants “strongly agreed” were considered to be particularly important.
Results
Participant Recruitment
Thirty-seven participants provided consent to participate, but only 30 participants completed all of the questionnaires (eFigure), which represents a participation rate of 81.1% (30/37).33 We were unable to calculate a response rate in relation to the number of e-mail invitations sent to potential participants due to the use of snowball and purposive sampling.33,34 In the final questionnaire, 3 additional reminders and a 4-week extension period were required to collect 30 responses.
Participant Demographics
Demographic information of the participants who returned the first questionnaire (n=33) is provided in Table 1. Apart from the selection criteria information, there were no demographic details collected from participants who did not respond to the first questionnaire (n=4). The majority of participants were female physical therapists who had undergone formalized training to become Pilates exercise instructors.
Participant Characteristics (n=33)
Thematic Analysis of Questionnaires
From 12 open-ended questions, a total of 109 themes were identified. These themes were used to generate questions for subsequent questionnaires regarding the indications, contraindications, precautions, and benefits and risks of using Pilates exercise in people with CLBP.
Items With and Without Consensus
After 3 questionnaires, consensus levels of agreement were reached on 87.2% (95/109) of the questions.
Indications.
With regard to indications to use Pilates exercise to treat people with CLBP, participants reached consensus on 100% (15/15) of the items (Tab. 2). Participants strongly agreed that a lack of body awareness and maladaptive movement patterns suggest a person with CLBP may benefit from undertaking Pilates exercise.
Indications for Using Pilates Exercise in People With Chronic Low Back Pain
Contraindications.
Consensus was achieved on only 55.5% (12/22) of the suggested contraindications for undertaking Pilates exercise (Tab. 3). Participants strongly agreed that diagnoses of pre-eclampsia and unstable fractures contraindicated the use of Pilates exercise to treat people with CLBP. There were several contraindications, however, that did not achieve consensus (n=10).
Contraindications of Pilates Exercise for People With Chronic Low Back Pain
Precautions.
Participants reached consensus on 100% (21/21) of precautions to undertaking Pilates exercise (Tab. 4). Participants strongly agreed that if a person with CLBP had unstable spondylolisthesis, or significant radiculopathy, Pilates exercise should only be undertaken with caution.
Precautions of Pilates Exercise for People With Chronic Low Back Pain
Benefits of Pilates exercise.
Consensus was reached on 100% (19/19) of questions related to the potential benefits of Pilates exercise for people with CLBP (Tab. 5). Participants strongly agreed that Pilates exercise may benefit people with CLBP by increasing their functional ability and their confidence with movement, exercise, and activities. Other proposed benefits included improvements in body awareness, postural control, and movement patterns and the provision of adjustable resistance with Pilates exercise equipment.
Potential Benefits of Pilates Exercise for People With Chronic Low Back Pain
Consensus also was reached in 100% (12/12) of questions relating to the rationale underlying the benefits of Pilates exercise, including questions on the active self-management approach of Pilates exercise and provision of low-impact, graded, individualized, and functionally relevant exercises for the back. Education regarding technique, supervision of exercises, and the use of trained and experienced instructors was theorized to explain the benefits of Pilates exercise for people with CLBP.
Risks of Pilates exercise.
Consensus was reached regarding 50.0% (4/8) of suggested risks of harm for people with CLBP undertaking Pilates exercise (Tab. 6). Participants did not strongly agree regarding the importance of any risk. Nevertheless, participants did agree that people with CLBP undertaking Pilates exercise may experience adverse events, such as increased low back pain, aggravation of their condition, injury, or excessive muscle tension.
Potential Risks of Pilates Exercise for People With Chronic Low Back Pain
Consensus was reached in 100% (12/12) of questions relating to the rationale underlying the risks of Pilates exercise, including those related to poor client concentration and technique; inadequate training of instructors, client education, exercise supervision, or equipment safety measures; inappropriate exercise prescription, rapid exercise progression, and excessive loads; or an overemphasis on core muscle activation, pain over function, and physical rather than psychosocial factors.
Repeated Questions
Items without consensus in the second questionnaire were repeated in the third questionnaire. A total of 9 items were repeated that related to the contraindications of Pilates exercise for people with CLBP (n=5) and the risks of Pilates exercise for people with CLBP (n=4). With repeat questioning, consensus was still not obtained for these items (Tabs. 2 and 6).
Concluding the Delphi Survey
A fourth questionnaire was not undertaken, as there were too few items without consensus (14/109). The majority of items without consensus also had been asked in both the second and third questionnaires (n=9). Meanwhile, the increasing number of reminders and extra time needed to receive 30 responses in the last questionnaire suggested participants were fatiguing in answering questionnaires.21
Discussion
This Delphi survey was a part of a larger survey that investigated the definition and application of Pilates exercise in people with CLBP.9 With regard to this Delphi survey, 30 physical therapists reached consensus after 3 questionnaires for 87.2% (95/109) of the questions. Consensus agreement was obtained for all items related to the indications, precautions, and potential benefits of using Pilates exercise to treat people with CLBP. Consensus agreement was reached on only 55.5% of items relating to contraindications and 50.0% of items referring to risks of Pilates exercise.
Indications
Participants strongly agreed that people with CLBP who have poor body awareness and maladaptive movement patterns may benefit from undertaking Pilates exercise. People with CLBP who have these deficits may be considered to have a “motor control impairment.”35–37 Future RCTs, therefore, could explore the efficacy of Pilates exercise in people with CLBP with and without a motor control impairment.
Contraindications to Pilates Exercise
Participants reached consensus regarding 55.5% of contraindications for people with CLBP undertaking Pilates exercise. Participants strongly agreed that pre-eclampsia was a contraindication to Pilates exercise. This contraindication is supported in the literature whereby women diagnosed with this condition are advised not to exercise due to the risk of morbidity and mortality to themselves and their fetus.38 Participants also strongly agreed that Pilates exercise was contraindicated in people with unstable fractures. This finding also is supported by research findings that unstable fractures require immobilization.39
Participants did not reach consensus regarding 44.5% of suggested contraindications (Tab. 3). These contraindications included both spinal pathologies (eg, spondylolisthesis) and other medical conditions not necessarily associated with CLBP (eg, hypertension). Future research should examine whether these contraindications to Pilates exercise are valid. In the meantime, it may be prudent to obtain medical clearance before people with these proposed contraindications undertake Pilates exercise.
Precautions to Pilates Exercise
Participants reached consensus on 100% of precautions to undertaking Pilates exercise in people with CLBP (Tab. 4). Participants strongly agreed that significant radiculopathy and unstable spondylolisthesis represent precautions for undertaking Pilates exercise. Pilates exercise trials thus far have focused on people with nonspecific CLBP, where symptoms cannot be attributed to a specific pathology.40 Future research, therefore, should explore the safety of Pilates exercise in people with a specific low back pain diagnosis.
It is acknowledged in the literature, however, that people with specific lumbar spine pathology and neurological issues should be treated differently from people with nonspecific CLBP.41,42 For example, a person with unstable spondylolisthesis may require stabilizing exercises and surgery.43 Similarly, a person with increasing neurological symptoms and signs requires a medical review.44
Potential Benefits of Pilates Exercise
Participants strongly agreed that Pilates exercise may increase the functional ability in people with CLBP and improve their confidence in moving, exercising, and daily activities. Research trials have reported improvements in functional ability, self-efficacy, fear-avoidance beliefs, and pain catastrophizing in people with CLBP.14–17 These improvements, however, may only be in the short term and may be equivalent to those achieved with other forms of exercise.15–17
Participants also strongly agreed that Pilates exercise may improve body awareness, posture, and movement patterns in people with CLBP. Currently, there are no research trials that have assessed changes in body awareness, dynamic posture, and movement patterns. There are reports, however, that Pilates exercise can reduce the degree of nonstructural scoliosis and improve the anticipatory postural adjustments of stabilizing trunk musculature with rapid arm movement.14,45 Further research is needed to explore changes in body awareness, postural kinematics, and movement patterns in people with CLBP.
Finally, participants strongly agreed that the use of specialized Pilates equipment, such as the Clinical Reformer (Balanced Body, Sacramento, California), provides benefit to people with CLBP. Specialized Pilates equipment has adjustable spring resistance, which allows the difficulty of exercises to be adapted according to an individual's ability.6,8 Future trials, therefore, should compare outcomes achieved with and without the use of specialized equipment to verify its importance.
Potential Risks of Pilates Exercise
Participants did not strongly agree regarding any risks of harm for people with CLBP undertaking Pilates exercise (Tab. 6). Documented cases of harm with Pilates exercise in the literature involved people without low back pain.18–20 One adverse event related to the breathing technique used in Pilates exercise, and another may be linked to the excessive loading of the cervical spine in flexion. The potential for risk of harm with Pilates exercise for people with CLBP, therefore, warrants further investigation.
Participants did agree that Pilates exercise may increase low back pain and aggravate pathology in people with CLBP. An increase in low back pain has been reported as an adverse event for people with CLBP undertaking exercise.41,42 Although 4% to 7% of people with LBP may experience ill-effects with exercise, only 0.06% will experience a serious adverse event, such as joint damage, a fracture, or herniated disk.41 Nevertheless, if a person has significant other comorbidities as well as CLBP, the incidence of adverse events with exercise may be higher.41
Participants did not reach consensus regarding 50.0% of the proposed risks of Pilates exercise in people with CLBP. These included the risk of not improving, causing injury to others, falling, or becoming anxious or hypervigilant. Future research needs to explore and quantify these risks for people with CLBP who undertake Pilates exercise.
Strengths
This is the first Delphi survey, to our knowledge, that has established consensus regarding the indications, contraindications, precautions, benefits, and risks of Pilates exercise in people with CLBP. There was a high participation rate in this survey (81.1%), with only 7 out of 37 participants dropping out the study. Findings were unlikely to be affected, as 4 of the participants who dropped out did not return any questionnaires.31
Thirty participants were deemed sufficient for this Delphi survey, as participants were similarly trained.46 Having a sample size greater than this may increase attrition and management issues, without improving the reliability of results.47 For example, responses of 23 participants in a well-defined knowledge area were reported to be stable in a Delphi survey with augmented sampling of 1,000 to 2,000 iterations.48
In Delphi surveys, the representativeness of results also is determined by the qualities of the participants.21,23,49 The credibility of findings is consequently enhanced by the education, experience, and training of participants (Tab. 1).21,23,50 All participants were registered physical therapists and had undertaken physical therapy education at university. In addition, 45.5% of the participants had undertaken postgraduate physical therapy study, and the average number of years of physical therapy work experience was almost 11 years.50
The design of this Delphi survey also ensured the quality and integrity of participants' responses.21,22 The use of open-ended and Likert response scale questions, multiple rounds of questionnaires, and repetition of questions without consensus allowed participants to reconsider and clarify their opinions as required.21,22,29 In addition, the provision of a summary of de-identified group responses encouraged participants to reflect on answers without pressure from individual group members.21,22
Consensus was defined a priori as 70% participant agreement or disagreement, which is similar to other Delphi surveys.21,31,32 Items of consensus were ranked in order of importance by a comparison of median scores for questions with a Likert response scale.32,51 Finishing the survey after 3 rounds was supported by the relative small number of items without consensus (14/109). Considering 9 of these questions were asked twice and the median responses did not differ between the second and third survey, it was unlikely that any subsequent surveys would produce different results.
Limitations
A Delphi survey assists in the development of a consensus of expert opinion, which represents a low level of evidence with potential for bias and thus may not be accurate.21,52 The iterative process of a Delphi survey may encourage participants to agree, even with de-identification of group responses.21,22 Findings, therefore, need to be validated and tested in subsequent clinical research.
Findings were based on the opinions of 30 Australian physical therapists experienced in Pilates exercise and thus cannot be generalized to reflect the opinions of all Australian physical therapists. The decision to include only Australian physical therapists also may limit the external validity of findings. Physical therapists from other countries, or other health professionals, may have different, but equally important, opinions that are not represented.21,22 Verification of the survey findings across various health professions and countries, therefore, is needed.
The majority of participants were female (n=30). This sex imbalance may reflect the Australian physical therapy workforce where the ratio of females to males is approximately 3:1.53 When responses between the sexes were compared, no consistent differences were noted. Given the size of the sample, however, it is difficult to rule out the influence of sex on the respondents' opinions.
It is possible that the 2 participants without formalized Pilates exercise instructor training may have provided opinions with less validity compared with participants who had undertaken courses. These participants, however, did have a postgraduate degree in physical therapy and significant physical therapy work experience (greater than 18 years). Future research, therefore, could examine the impact of differences in Pilates training on the clinical practice of physical therapists.
The suggested indications, contraindications, and precautions of Pilates exercise for people with CLBP have not been discussed in the literature. For example, poor body awareness and maladaptive movement patterns were not mentioned as predictors of success with Pilates exercise in the recently published clinical prediction rule for people with CLBP.10 The lack of information in the literature makes it difficult to triangulate Delphi survey findings with research and highlights the need for further clinical trials exploring this area.
Several of the proposed benefits and risks of Pilates exercise for people with CLBP also have not been verified by clinical trials.8 Some benefits, such as increased body awareness, do not have specific outcome measures that have appropriate psychometric properties in people with CLBP.54 Although the development of appropriate outcome measures may assist in determining the effectiveness of Pilates, the relevance of these benefits to people with CLBP should be examined.8,55 With regard to risks of harm with Pilates exercise, potential adverse events and the likelihood of them occurring in people with CLBP also need to be examined.
Implications
This Delphi survey provides insight into characteristics of people with CLBP who may benefit, or not benefit, from undertaking Pilates exercise. This information may be used by clinicians to enhance the safety and effectiveness of Pilates exercise interventions. The validity of the suggested indications, contraindications, and precautions, however, needs to be confirmed with further research. Future research also should examine items without consensus, such as the contraindications of Pilates exercise for people with CLBP.
This survey provides valuable information regarding the potential benefits and risks of Pilates exercise for people with CLBP. The list of potential benefits may assist clinicians and researchers in the selection of relevant outcome measures to estimate the treatment effect of Pilates in people with CLBP. Meanwhile, the list of potential risks of harm of Pilates exercise for people with CLBP highlights the importance of screening for comorbidities and of monitoring and preventing adverse events.
Footnotes
Ms Wells, Dr Kolt, and Dr Bialocerkowski provided concept/idea/research design and data analysis. All authors provided writing. Ms Wells and Dr Bialocerkowski provided data collection. Ms Wells, Dr Marshall, and Dr Bialocerkowski provided project management. Dr Kolt and Dr Bialocerkowski provided consultation (including review of manuscript before submission).
The Human Research Ethics Committee of the University of Western Sydney provided ethical approval for this study.
A poster presentation summarizing some of the findings of the study was presented at the Eighth Interdisciplinary World Congress on Low Back and Pelvic Pain; October 27–31, 2013; Dubai.
- Received November 20, 2013.
- Accepted March 1, 2014.
- © 2014 American Physical Therapy Association