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Trial registered on ANZCTR


Registration number
ACTRN12618000446268
Ethics application status
Approved
Date submitted
28/02/2018
Date registered
28/03/2018
Date last updated
26/07/2019
Date data sharing statement initially provided
26/07/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Is pelvic floor dysfunction associated with development of transient low back pain during prolonged standing?
Scientific title
Is there an aberrant trunk muscle coactivation in women with stress urinary incontinence that is associated with development of transient low back pain during prolonged standing?
Secondary ID [1] 294183 0
Nil Known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
stress urinary incontinence 306818 0
Low Back Pain 306819 0
Condition category
Condition code
Musculoskeletal 305925 305925 0 0
Other muscular and skeletal disorders
Neurological 306111 306111 0 0
Other neurological disorders
Renal and Urogenital 306113 306113 0 0
Other renal and urogenital disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This is a self-controlled case series design (SCCS), a method used for investigating the association between a transient exposure (prolonged standing) and an adverse event (development of back pain). SCCS is considered to be a superior design to cohort or case-control studies when there is uncertainty over control of fixed confounders (Petersen, Douglas, & Whitaker, 2016), in this case UI. Participants will be positioned on a 0.50 x 0.46 m force platform and instructed to stand in their usual manner for prolonged standing (120 min). They must stay within the confines of the force platform borders and may not rest limbs on the tray in front of them. Participants will be given a set of tasks similar to those performed in prolonged standing occupations, such as, ‘computer work’, ‘card dealing’, ‘checkout scanning’ and ‘small object assembly’ (Nelson-Wong et al., 2008). This protocol has been established as a valid tool for predicting risk for chronic LBP in apparently healthy populations (Nelson-Wong & Callaghan, 2010; Nelson-Wong & Callaghan, 2014). The intervention is simply the prolonged time spent standing and will be administered to all participants. It will be administered by one of the study investigators and overseen by a physiotherapist.
Intervention code [1] 300610 0
Diagnosis / Prognosis
Intervention code [2] 300611 0
Lifestyle
Comparator / control treatment
The control group are approx 30 apparently healthy women over the age of 18 with no reported history of UI or Low Back Pain. They will undergo the same intervention of prolonged standing of 120min.
Control group
Active

Outcomes
Primary outcome [1] 304958 0
First primary outcome is Low Back Pain. Measured at baseline and each 10min interval. Pain level will be measured on a 100 mm visual analogue scale (VAS) with end-points of ‘no-pain’ (far left) and ‘worst pain imaginable’ (far right) (Huskisson, 1974). Pain quality is assessed at the primary timepoint via McGill Pain Questionare (Melzack, 2005; Trudeau et al. 2012)
Timepoint [1] 304958 0
Baseline and repeated every 10 minutes to 120 minutes (primary timepoint).
Primary outcome [2] 304959 0
muscle coactivation coefficients between the PFM and IO/TrA. Muscle activation will be measured by surface electromyography (sEMG). Raw EMG will be sampled at 1000Hz from electrodes adhered bilaterally as per international guidelines (SENIAM; Hermens et al., 2000). The EMG signal will be processed as per Nelson-Wong, Gregory, Winter & Callaghan, 2008 to examine the signal overlap between muscle pairs. Cross-correlation analyses will be used to quantify coactivation between the muscle pairs, the coefficient of co-activation will be expressed as a % for each block (Nelson-Wong et al., 2010).
Timepoint [2] 304959 0
Baseline and repeated every 10 minutes to 120 minutes (primary timepoint).
Primary outcome [3] 305141 0
Postural sway, measured as the range of CoP trajectory. Centre of pressure (CoP) displacement in the anterior-posterior and mediolateral directions will be recorded from a force platform samplig at 1000Hz with amplifier gain of 4000 (AMTI, Watertown, MA). We will compare the CoP range for each block as well as dynamic structure of the CoP characterized by sample entropy (SampEn) (Rhea, Kiefer, Haran, Glass, & Warren, 2014).
Timepoint [3] 305141 0
Baseline and every 10 min to 120min (primary timepoint)
Secondary outcome [1] 343742 0
[This is a primary outcome] Muscle coactivation patterns gluteus medius bilaterally as coefficient of coactivation (%). Muscle activation will be measured by surface electromyography (sEMG). Raw EMG will be sampled at 1000Hz from electrodes adhered bilaterally as per international guidelines (SENIAM; Hermens et al., 2000). The EMG signal will be processed as per Nelson-Wong, Gregory, Winter & Callaghan, 2008 to examine the signal overlap between muscle pairs. Cross-correlation analyses will be used to quantify coactivation between the muscle pairs, the coefficient of co-activation will be expressed as a % for each block (Nelson-Wong et al., 2010).
Timepoint [1] 343742 0
[This is a primary outcome measure so will be measured at baseline and every 10 min to 120min (primary timepoint)]
Secondary outcome [2] 344304 0
Assessment of Pelvic Stability will be made via active straight leg raise test as per Mens et al., 1999;2001. Quality/ability of movement will be assessed as per Mens and colleagues using a six-point scale to rate the level of difficulty: "not difficult at all = 0; minimally difficult = 1; somewhat difficult = 2; fairly difficult = 3; very difficult = 4; unable to do = 5" (2001, p. 1169).
Timepoint [2] 344304 0
Measured at baseline and at primary timepoint 1.
Secondary outcome [3] 344731 0
Assessment of general physical ability and fitness using a 4-week activity scale measured via Minnesota Leisure Time Physical Activity Questionnaire (Folsom et al., 1986)
Timepoint [3] 344731 0
Baseline
Secondary outcome [4] 344732 0
Assessment of trunk stability will me made by measuring time to fatigue in side support as per Hicks et al., 2005 & McGill et al., 1999.
Timepoint [4] 344732 0
Baseline
Secondary outcome [5] 344929 0
Pelvic Asymmetry Ratio will be measured by the following equation as per Al-Eisa et al., 2006 (ASIS height difference/ASIS width) + (PSIS height difference/PSIS width).
Timepoint [5] 344929 0
Baseline

Eligibility
Key inclusion criteria
Inclusion Criteria for UI group:
Participants will be included if they have current Stress Urinary Incontinence symptoms (QUID), experiencing leakage at least once per month (min score of 1 point (out of 32) for the Total M-ISI Severity Domain). Continence type will be evaluated with the Questionnaire for Urinary Incontinence Diagnosis (QUID), which is a valid and reliable tool to assess the potential for pelvic floor dysfunction (Bradley et al., 2010). Symptom severity will be assessed with the Michigan Incontinence Symptom Index (M-ISI).
Inclusion Criteria for Healthy Controls:
Healthy with no history of UI symptoms and Michigan Incontinence Symptom Index (M-ISI) score of 0.
Minimum age
18 Years
Maximum age
65 Years
Gender
Females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Exclusion Criteria for Both groups:
Any lifetime event of LBP sufficient to cause > 3 days of missed work/school/sport or seeking attention/treatment from medical personnel either physiotherapy, osteopathy, medical doctor or chiropractor; hip pain or pathology including previous hip surgery; current pregnancy or within 6 months’ post-partum; those with severe allergies or upper respiratory infections.
Exclusion Criteria for UI Group:
UI that is deemed from the QUID outcome to be urge UI or mixed UI;

Study design
Purpose of the study
Diagnosis
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

The people administering the treatment/s

Intervention assignment
Single group
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Sample size was calculated as needed to achieve beta = 0.85 with alpha = 0.05, utilising a relative risk incidence of rho = 3 and ratio of risk to observation period of r = 0.142 (sourced from previous studies Bussey et al., 2016; Nelson-Wong & Callaghan, 2010).
The statistical analysis will be undertaken with R (version 2.15.3, R core team, 2012). To determine whether co-activation patterns of the pelvic floor and trunk muscles can predict transient low back pain during the prolonged standing task a logistic regression model will be used. For this, Pain status (Pain and No Pain) will be entered in the model as the response variable and muscle coactivation coefficients, CoP, parity history and BMI as the predictors. To determine whether UI status predicts pain outcome a linear regression model with a predictor variable of UI status and the response variable ‘greatest change in VAS score’.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 9636 0
New Zealand
State/province [1] 9636 0
Otago

Funding & Sponsors
Funding source category [1] 298817 0
University
Name [1] 298817 0
University of Otago Researach Committee
Address [1] 298817 0
362 Leith St, North Dunedin, Dunedin, New Zealand, 9016
Country [1] 298817 0
New Zealand
Primary sponsor type
Individual
Name
Melanie Bussey
Address
55 Union Street West, Dunedin, New Zealand, 9054
Country
New Zealand
Secondary sponsor category [1] 298011 0
Individual
Name [1] 298011 0
Daniela Aldabe
Address [1] 298011 0
270 Great King Street, Department of Anatomy, University of Otago, Dunedin, New Zealand, 9016
Country [1] 298011 0
New Zealand
Secondary sponsor category [2] 298013 0
Individual
Name [2] 298013 0
Daniel Ribeiro
Address [2] 298013 0
325 Great King St, School of Physiotherapy, University of Otago, Dunedin, New Zealand, 9016
Country [2] 298013 0
New Zealand
Secondary sponsor category [3] 298014 0
Individual
Name [3] 298014 0
Stephanie Madill
Address [3] 298014 0
1121 College Dr, School of Physical Therapy, University of Saskatchewan, Saskatoon, Canada, SK S7N.
Country [3] 298014 0
Canada
Other collaborator category [1] 279972 0
Individual
Name [1] 279972 0
Niels Hammer
Address [1] 279972 0
270 Great King Street, Department of Anatomy, University of Otago, Dunedin, New Zealand, 9016
Country [1] 279972 0
New Zealand
Other collaborator category [2] 279973 0
Individual
Name [2] 279973 0
Stephanie Woodley
Address [2] 279973 0
270 Great King Street, Department of Anatomy, University of Otago, Dunedin, New Zealand, 9016
Country [2] 279973 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 299764 0
University of Otago Human Ethics Committee (Health)
Ethics committee address [1] 299764 0
362 Leith St, North Dunedin, Dunedin 9016
Ethics committee country [1] 299764 0
New Zealand
Date submitted for ethics approval [1] 299764 0
18/01/2018
Approval date [1] 299764 0
05/02/2018
Ethics approval number [1] 299764 0
H18/009

Summary
Brief summary
Prolonged standing has been associated with an increased prevalence of back pain in both laboratory and epidemiologic studies (Andersen et al 2007) and is recognised as a potential workplace hazard for employees who may stand for up to 75% of their work time such as, retail staff, assembly line workers, and healthcare personnel, among others (“Standing Problem,” 2005; Parent-Thirion et al., 2012).
Recent research indicates that prolonged standing might lead to transient LBP in workers without previous history of back injury (Gallagher et al 2014; Marshall et al 2011; Nelson-Wong et al, 2010). Those individuals who developed pain during standing work usually experience first symptoms within 15 to 45 min, in conjunction with significant muscle co-activation anomalies, such as high co-activation of the gluteus medius, compared to non-pain developers. Transient back pain by definition exists solely during the exposure time and dissipates quickly once the standing ceased. However, Nelson-Wong and Callaghan (2014) found that transient LBP developers were 3 times more likely to experience chronic LBP over the next 24 months, seek medical care within 3 years of their participation, and report multiple episodes of chronic LBP. Although LBP during the 2-hour standing protocol is transient in nature, it has been shown to be a positive predictor for future chronic and recurrent LBP (Callaghan et al., 2015; Nelson-Wong & Callaghan, 2014).
LBP is more prevalent in women than men (Schneider, Randoll, & Buchner, 2006). Further, many recent studies have highlighted an association between LBP and urinary incontinence (UI) (Arab, Behbahani, Lorestani, & Azari, 2010; Bush et al., 2013; Cassidy et al., 2017; Eliasson, Elfving, Nordgren, & Mattsson, 2008). In fact, women with UI are more than twice as likely to experience frequent back pain as those without UI (Smith, Russell, & Hodges, 2009). Additionally, women with greater severity of UI also report an increased severity and greater disability related to their back pain (Kim et al., 2011). The function of the pelvic floor muscles in supporting continence is well known (Dumoulin, 2010; Price, Dawood, & Jackson, 2010). However, the pelvic floor muscles play important roles in spinal stability as they naturally coactivate with other trunk muscles such as the transvers abdominis (Hodges, Sapsford, & Pengel, 2007). Given the pelvic floor muscles’ dual roles, it is logical to hypothesize a relationship between pelvic floor function, continence status and the development of lower back pain.
The primary objective of this research is to improve work-related health outcomes for women by elucidating significant predictors of LBP during prolonged standing. The main purpose of the study is to determine whether co-activation patterns between the pelvic floor and trunk muscles during a 2-hour prolonged standing task can predict transient low back pain in healthy women with and without pelvic floor dysfunction.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 81494 0
Dr Melanie Bussey
Address 81494 0
55 Union St West, School of Physical Education Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand, 9054
Country 81494 0
New Zealand
Phone 81494 0
+6434798981
Fax 81494 0
Email 81494 0
melanie.bussey@otago.ac.nz
Contact person for public queries
Name 81495 0
Dr Melanie Bussey
Address 81495 0
55 Union St West, School of Physical Education Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand, 9054
Country 81495 0
New Zealand
Phone 81495 0
+6434798981
Fax 81495 0
Email 81495 0
melanie.bussey@otago.ac.nz
Contact person for scientific queries
Name 81496 0
Dr Melanie Bussey
Address 81496 0
55 Union St West, School of Physical Education Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand, 9054
Country 81496 0
New Zealand
Phone 81496 0
+6434798981
Fax 81496 0
Email 81496 0
melanie.bussey@otago.ac.nz

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
We are undecided at this time.
What supporting documents are/will be available?
Study protocol
How or where can supporting documents be obtained?
Type [1] 3445 0
Study protocol
Citation [1] 3445 0
Bussey, M. D., Aldabe, D., Ribeiro, D. C., Madil, S., Woodley, S., & Hammer, N. (2019). Is pelvic floor dysfunction associated with development of transient low back pain during prolonged standing? A protocol. Clinical Medicine Insights: Women's Health, 12. doi: 10.1177/1179562X19849603
Link [1] 3445 0
Email [1] 3445 0
Other [1] 3445 0
Attachment [1] 3445 0
Summary results
No Results