|Ahead of print publication
Effectiveness of pelvic proprioceptive neuromuscular facilitation on trunk stability and gait parameter in stroke patients: A systemic review
Smit R Shah1, Heta Doshi2, Chaitali Shah3
1 Assistant Professor at Shrimad Rajchandra College of Physiotherapy, M. P.T In Neurology And Psychosomatic Disorders, Uka Tarsadia University, Surat, Gujarat, India
2 Assistant Professor at Neotech Institute of Physiotherapy, M. P.T In Musculoskeletal & Sports, Vadodara, Gujarat, India
3 Associate Professor, M.P.T (Neurology), At Parul Institute of Physiotherapy, Parul University, Gujarat, Gujarat, India
|Date of Submission||22-Jul-2020|
|Date of Decision||15-Oct-2020|
|Date of Acceptance||26-Mar-2021|
Smit R Shah,
Assistant Professor at Shrimad Rajchandra College of Physiotherapy, M. P.T In Neurology And Psychosomatic Disorders, Uka Tarsadia University, Surat
Source of Support: None, Conflict of Interest: None
Background and Purpose: Neurological deficits after stroke are impaired motor functions including balance and gait. Such gait deviations are associated with decreased gait velocity followed by a change in the timing and distance with each step cover. The pelvic proprioceptive neuromuscular facilitation (PNF) facilitates the trunk and lower extremity motion and also provides the stability of trunk. The aim of this review is to systematically evaluate the effectiveness of Pelvic PNF on gait and trunk stability in stroke patients. Methods and Analysis: This systematic review was conducted according to the Preferred Reporting Items for Qualitative Systematic Reviews guidelines. The electronic databases were searched for a quality assessment from the start of databases with all studies of review interest being “Pelvic PNF” exercise, and the outcome of interest was related to trunk function and gait parameters. The characteristics of each study are outlined in Population, Intervention, Comparison and Outcome, and the findings using the Critical Appraisal Skills program for Randomized Controlled Trials were used to assess methodological quality. Results: The reviews in these studies were interest-related “Pelvic PNF.” The results of these reviews of all studies suggest that Pelvic PNF significantly improves trunk stability as well as gait parameters which proves this technique to be most applicable in stoke patients. Conclusion: This review had looked at the Pelvic PNF exercises to physiotherapy care for treatment of hemiparetic patients and demonstrated significant improvement in trunk stability and gait parameters such as cadence, gait velocity, and stride length.
Keywords: Critical Appraisal Skills Program, gait parameters, pelvic proprioceptive neuromuscular facilitation, PICO, stroke, trunk stability
|How to cite this URL:|
Shah SR, Doshi H, Shah C. Effectiveness of pelvic proprioceptive neuromuscular facilitation on trunk stability and gait parameter in stroke patients: A systemic review. Med J DY Patil Vidyapeeth [Epub ahead of print] [cited 2021 Dec 6]. Available from: https://www.mjdrdypv.org/preprintarticle.asp?id=327820
| Introduction|| |
The World Health Organization (WHO) defines stroke as “Rapidly developing clinical signs of focal (or global) disorder of cerebral functions, with symptoms lasting 24 h or longer or leading to death, with no apparent cause other than vascular origin.” Stroke is one of the major causes of morbidity and mortality worldwide, described as the sudden development of a neurological deficit caused by blood supply abnormalities. The incidence of stroke in India was 130/100,000 people/year, according to the WHO (November 16, 2011). The annual incidence rate of stroke in India is 124/100,000, with a prevalence of 136/100,000 in urban areas and 165/100,000 in rural populations. The Indian Medical Research Council estimates that, among noncommunicable diseases, stroke contributes 41% of deaths and 72% of life-adjusted disability.
Common problems after stroke are impaired motor functions including balance and gait, contralateral sensory impairment, altered tone of trunk muscles, abnormal synergy patterns, abnormal reflexes, altered coordination and balance, lack of postural control, perceptual deficits, cognitive limitations, visual deficits, aphasia, and depression. Neurological deficits that lead to loss of leg strength and impaired balance are two factors that correlate to walking ability.,
In stroke patients, loss of trunk muscle control is frequently found because trunk control is the capacity of the trunk muscle to keep the body upright, adjust the weight change, and execute selective trunk motion to keep the Center of mass (COM) within the base of support during static and dynamic postural adjustments. The trunk is a part of pelvis which combines and supports the extensor motion. The motion of pelvis occurs by the trunk muscles because the pelvis pattern depends on the amount of trunk motion. Lower trunk and hip muscle co-activity provides the pelvis with stability, serving the purpose of postural stabilization and transforming the load to the lower limbs during standing.,
The modified recruitment of hip abductors and extensors on the most impacted leg affects the strength of the pelvis which leads more in lateral and anterior pelvic, and the major impairment that decreased hip extension during stance phase of walking following stroke. Such gait deviations are associated with decreased gait velocity, followed by a change in the timing and distance with each step cover. Patients who survive strokes experience improvement in stride length, gait velocity, cadence, step length, single-limb support, stride time, and stance over time. Gait was analyzed using comprehensive parameters which were measurements determined from bilateral lower extremity, which include gait velocity, cadence, stride length, and stance phase duration.
The method of proprioceptive neuromuscular facilitation (PNF) is a neurophysiological model-based approach which is widely used clinically to improve the gait of patients with hemiplegia. This method is based on the use of maximum resistance to movement, which is executed in diagonal and spiral directions in proprioceptors to promote a larger neuromuscular response that improves the strength, flexibility, and balance of muscles and tendon by stimulating the muscle spindle and Golgi tendon., The Pelvic PNF facilitates the trunk and lower extremity motion and also provides the stability to trunk. It also promotes the exploration of postural reflexes and prioritizes eccentric muscle contraction, stimulating agonist activity.
The purpose of this review is to systematically evaluate the effectiveness of pelvic PNF on gait and trunk stability in stroke patients.
| Methods and Analysis|| |
Types of studies
This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The inclusion criteria for this review were all clinical trial studies (with or without a control group), cross-sectional studies, and quasi-experimental studies, which examined the effects of pelvic PNF. The exclusion criteria for this review were qualitative and meta-analysis studies, non-English articles, and nonfull text articles. All articles included in this study were reviewed without time restrictions.
Types of participants
This study review involves patients of any age with ischemic or hemorrhagic stroke. Stroke must be diagnosed according to the WHO definition (rapidly developing clinical signs of focal [or global] disturbance of cerebral function, lasting more than 24 h or leading to death, with no apparent cause other than that of vascular origin) or confirmed by computed tomography or magnetic resonance imaging. This study had no limitation for relation of time from the onset of stroke. Patients having subarachnoid hemorrhage or subdural hematoma were excluded from the study.
In this study included all data were first electronically searched in databases for a quality assessment from the start of databases to December; 2020.
These databases included Google Scholar, PubMed, EBSCO Host, and Cochrane Library. Keywords used included pelvic PNF in stroke and exercise. The prepared search strategy used the MESH terms (Medical Subject Headings). Details on the study selection process are reported in a flowchart [Figure 1]. Further details with regard to search strategies used for each database were as follows:
- EBSCO host: “Pelvic PNF,” “Stroke” Refined by: academic, peer-reviewed journals and Language: English
- Cochrane Library: “Pelvic PNF,” “Stroke”
- Google Scholar: “Pelvic PNF,” “Stroke” (Title/Abstract)
- PubMed: “Pelvic PNF,” “Stroke” (full-text articles).
There was no restriction in the assessment of physical and psychological symptoms. The exposure of interest was “Pelvic PNF” exercise, and the outcome of interest was related to trunk function and gait parameters. Ethical approval was not required for this study because no primary data was collected [Figure 2].
The risk of bias for all the included studies was independently assessed by two authors following the criteria of the Cochrane risk-of-bias tools and taking into consideration the differences in study designs.
Two reviewers (SS, BP) independently undertook the search of each database to ensure consistency and reproducibility. The reviewers compared the number of “hits” after each database search, where discrepancies occurred, the error was identified and the search re-run until there were no errors. The results from each database were exported into the industry-standard bibliographic software tool Endnote™ to separate database folders. All folders were then combined and duplicates were removed. The remaining studies were imported to Covidence, a data management software for systematic reviews, where two rounds of screening took place. In the first round, both reviewers (SS, BP) independently screened all study titles and abstracts. Any disagreement that arose was resolved using the following system: Maybe + Yes = Yes, Maybe + Maybe = Yes, Maybe + No = No, Yes + No = conflict. Both reviewers met to discuss and resolve any conflicts. Full text was obtained for all studies where there was insufficient detail in the abstract to determine eligibility, where there was no available abstract, or where the study was likely to be included based on title and abstract. A second round of screening of the full text of each study against the eligibility criteria was then undertaken by the same one reviewer (CS) and reasons for exclusions were recorded.
Risk of bias
The methodological quality of each included study was assessed independently by all the three reviewers using the Critical Appraisal Skills Program (CASP) Randomized Controlled Trial critical appraisal tool and Clinical Prediction Rule. Initially, reviewers met to discuss the agreed interpretation of items in the CASP, where a scoring system of yes = 1, no and can't tell = 0, was used. Reviewers then met to compare findings of each CASP and any disagreements were discussed until consensus was reached. Potential methodological and reporting biases were not formally assessed by the CASP but also independently considered by two team reviewers and then discussed to resolve any conflicts. The hierarchy of all studies was assessed according to the National Health and Medical Research Council (NHMRC) designation of levels of evidence. An agreed interpretation of results was previously established by all research team members and disagreements were resolved through discussion with the project supervisor.
The data were extracted by all reviewers and collected into a specifically customized template which included information related to the population, intervention, comparator, outcome measures, and results. The process of data extraction using this template was previously tested with one study by both reviewers together to ensure data would be interpreted and extracted consistently. Data extraction of the remaining studies was then completed independently, and findings were compared between the same two reviewers before the process of condensing and refining was implemented. A narrative analysis of included studies was subsequently performed as the small number of studies and variability in outcome measurement a meta-analysis was not appropriate. The statistical effects of the interventions on validated measures for gait parameters and trunk function were presented and compared using P values with an alpha level set at 0.05 or using 95% confidence intervals.
A review team utilized the NHMRC FORM methodology to grade and provides a framework for synthesis of the evidence from the literature. The NHMRC FORM methodology considers the evidence provided in all studies to assist in the development of a specific recommendation. There are five main components:  quantity and quality of the evidence, consistency, clinical Impact, generalizability, and applicability. This framework provided a basis for evidence-based recommendations for implementation in clinical practice and identified where care may need to be taken in the application of the findings.
| Results|| |
The search strategy generated 23 “hits” through all sources. Following removal of duplicates, title and abstract screening, and screening of full-text versions, nine studies were included in the review. [Figure 2] and [Figure 3] provides an overview of the study selection process.
Ranking and methodological quality
An overview of the NHMRC designation of levels of evidence and a summary of the collated findings and consensus agreement from all the researchers for the critical appraisal for individual studies are presented in [Table 1] and [Table 2]. All studies scored between 5 and 9 out of a possible total score of 10 [Table 1] and [Table 2].
The CASP analysis revealed several inherent methodological biases across the studies. All studies had focused questions, treated the intervention and comparator groups equally, and presented results that could be applied and would be considered beneficial. None of the study participants were blinded to the treatment, which is not surprising due to the nature of both interventions and comparators. Studies scored “0” on the fourth CASP item if they did not employ an intention-to-treat analysis or did not provide explanations for participant dropout in randomized controlled trial study. Only studies by Patni and Ribeiro et al. demonstrated the potential for a comparative study bias.
Finally, all studies provided some statistical measure of the significance of results. The team members acknowledged the potential for other biases not formally assessed by the CASP to affect the validity of results. All studies were potentially subject to the Hawthorne effect because both the intervention and comparator involved supervision by an educated therapist. The potential for attention bias must also be acknowledged because in each study, the intervention group received a longer supervised session than that of the control group. This was due to the additional exercises involved in the intervention. In addition, no explicit mention of the training provided to therapists was provided in any study, potentially contributing to proficiency bias. It was difficult to determine the impact of contamination bias due to a lack of reported restrictions preventing exposure of control groups to the intervention.
A total of nine studies with publication dates of the included studies ranged from 2012 to 2019. They consisted of seven randomized controlled trials and two comparative studies. The characteristics of each study were outlined in PICO with findings in terms of author, research aims, sample, measurement tools used, type and duration of exercise and types of research [Table 3].,,,,,,,
The participants in the studies ranged from 40 to 70 years' age group and all studies included both male and female participants having stroke.
Type of intervention
Across all studies, the treatment protocol for the comparator consisted of Pelvic PNF and trunk stability exercises (truncal exercises), while the intervention protocol included the Pelvic PNF exercises. All studies clearly stated the intervention to include Pelvic PNF and truncal exercises. The intervention periods across the studies for intervention and comparator and or other groups consisted of 3, 4, and 6 or, 12 week's treatment programs, with training frequency ranging from 3 to 5 sessions/week. However, consistent significant differences in any one of the outcomes were found between all the studies. Pelvic PNF included anterior elevation and posterior depression, with techniques used being rhythmic initiation, slow reversal and agonist reversal, whereas truncal exercises were performed as bridging, trunk flexion, extension, and rotation in all studies.
Summary of result
[Table 4] summarizes a review of the results all the nine articles on all outcomes related to gait parameters and trunk functions.,,,,,,,
NHMRC body of evidence framework
[Table 5] synthesizes the results of the included studies using the NHMRC FORM framework. The included studies, despite being classified as high-level evidence forms, could only be considered as moderate quality due to methodological concerns involving lack of blinding and true randomization.
| Discussion|| |
This systemic review aimed to evaluate the effectiveness of Pelvic PNF on trunk stability and gait parameters in stroke patients' studies undertaken within a qualitative social science framework, to consider the contribution and limitation of time and purpose for future directions.
We did not aim to conduct a meta-analysis, methodologies for which are now being developed to synthesize qualitative research findings of the systemic review related to this study.
Hence, this review focused on the different techniques of PNF, that is, pelvic PNF that are currently applied in stroke survivors to explore their influence on trunk movement and gait performance.
Pelvic PNF has been a relevant approach in therapeutic techniques for years. More recently, the focus on trunk stability has allowed the techniques of PNF, that is, pelvic PNF to become an integral part of this type of exercise programming. Pelvic PNF should be incorporated into any gait parameters and trunk movements. This systemic review investigated the effectiveness of Pelvic PNF exercises on trunk movement and gait parameter in stroke patients.
All the nine studies demonstrated significant improvement in trunk stability and gait parameters such as cadence, gait velocity, and stride length. No adverse effects of treatment were reported in any of the nine studies. The results of this review are most applicable to stoke patients.
According to one of the review article refer by Kabat et al., the probable mechanism with the use of PNF to facilitate the neuromuscular mechanism, that by stimulating the proprioceptors, and results that a higher motor response can be achieved by using facilitating techniques when we additionally add more resistance. Facilitation techniques followed from various factors such as use of specific movement patterns, application of stretch, and to induce irradiation use of more resistance. These facilitatory techniques may assist with encouraging movement and stability of trunk, thus increasing the motor control and motor learning, thereby enhancing the participant's performance in posttreatment group.
Shinde and Ganvir have conducted a meta-analysis and stated that the number of sensory stimulation coming from periphery was higher in PNF position than that in normal position which produces change in pyramidal tract excitability. In PNF, Shimura has reported stronger excitation of the cortical areas, leading to alterations in thresholds of various numbers of motor neurons, which was reflected in motor-evoked potentials that required a sensory input from the periphery.
The Pelvic PNF approach to treatment uses the principle that control of motion proceeds from proximal to distal body regions. Facilitation of trunk control, therefore, was used to influence the extremities. The specific pattern of Pelvic PNF consisting anterior elevation and posterior depression is an integral aspect when gait swing is considered. As this movement pattern of the pelvis is reinforced, it increases motor response and motor learning that occurs due to the facilitatory techniques along with resistance, thus leading to the improvement in the gait parameters. All these techniques help to facilitate pelvic motion and stability and enhance gait performance indirectly through irradiation, thereby improving performance of participants in stroke patients. The result of the present study found that pelvic PNF enhances trunk stability and gait parameters in stroke patients.
The systematic review has several limitations related to review processes, study outcomes, and methodology. A comprehensive search strategy including searching studies from related systematic reviews gleaned nine studies that met the inclusion criteria. Included studies involved a small number of participants, were at unclear-to-high risk of bias, and were highly heterogeneous in terms of study design and characteristics of intervention (exercise type and duration). Due to the different affects of these interventions and different exercise type and duration, findings from that study are prone to bias. Therefore, publication bias cannot be excluded. Common methodological concerns included lack of blinding to treatment, which is difficult in an ongoing physiotherapy program. Included studies were also mostly medium to low-level research designs (NHMRC Level II and III Interventions). For all the studies main outcomes related to trunk movements and gait parameters, different outcome measures were used, resulting in an inability to undertake a meta-analysis, thus preventing combining the data from a number of studies to identify the overall effect. Although the articles whose publication language is not English and the full text is not available for could not be reached.
| Conclusion|| |
Overall, it can be concluded pelvic PNF significantly improves gait and trunk stability in stroke patients.
This study discovered that there is necessity of further research into clinical application of Pelvic PNF particularly in stroke rehabilitation with wider variety of patient groups and higher methodological quality to provide stronger evidence base for future practice. Surveys on the attitude of the physiotherapy practitioners would also be helpful to investigate the current status of Pelvic PNF practice in stroke rehabilitation.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]