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Trial registered on ANZCTR


Registration number
ACTRN12620001243909
Ethics application status
Approved
Date submitted
5/09/2020
Date registered
20/11/2020
Date last updated
2/06/2022
Date data sharing statement initially provided
20/11/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
The effect of isometric versus isotonic exercise on pain and strength in people with hamstring tendon pain.
Scientific title
A randomised, cross-over trial of the effect of isotonic and isometric exercise on pain and strength in proximal hamstring tendinopathy
Secondary ID [1] 299622 0
Nil known
Universal Trial Number (UTN)
U1111-1242-4645
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Proximal hamstring tendinopathy 314930 0
Condition category
Condition code
Musculoskeletal 313283 313283 0 0
Other muscular and skeletal disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Isometric and Isotonic exercise

Isometric exercise:
One session of isometric exercise (5 repetitions of 45 seconds), administered face-to-face by an experienced physiotherapist. Intervention will take place at LaTrobe University.

Participants will be asked to perform a prone hamstring curl, with the knee at 45 degrees of flexion.
Isometric exercise will be undertaken at 50-65% of maximum voluntary isometric contraction, with the intensity measured using a Biodex dynamometer.
The duration of the intervention is approximately 15 minutes including rest periods between repetitions.

Participants will be asked to attend three sessions in total.
Session one is an orientation session to the testing equipment. Sessions two and three are either of the isometric or isotonic intervention (the order is randomised). There is a 3-7 day washout period between all sessions.

The total time commitment for session one is approximately 30-45 minutes

The total time commitment for sessions two and three is approximately 90 minutes, including approximately 15 minutes of intervention.
Intervention code [1] 317639 0
Rehabilitation
Comparator / control treatment
Isotonic exercise:
One session of isotonic exercise (5 sets of 9 repetitions), administered face-to-face by an experienced physiotherapist. Intervention will take place at LaTrobe University.

Participants will be asked to perform a prone hamstring curl using the Biodex dynamometer, with the knee angle varying from 0 to 60 degrees. A two second concentric and a three second eccentric contraction will be used.
The total duration of intervention is approximately 15 minutes including rest periods between sets.
The level of intensity for isotonic exercise is at 100% of the participant's best effort across 9 repetitions, i.e their 9 repetition maximum.
Control group
Active

Outcomes
Primary outcome [1] 323876 0
Pain (measured on a 100 mm Visual Analogue Scale) during a functional task (modified arabesque)
Timepoint [1] 323876 0
Session 1 (orientation): baseline
Sessions 2 and 3: pre-intervention, and 0, 45 minutes and 24 hours after each intervention session (primary timepoint is 0 minutes after intervention)
Primary outcome [2] 323877 0
Knee flexion strength, measured with a Biodex dynamometer
Timepoint [2] 323877 0
Session 1 (orientation): baseline
Sessions 2 and 3: pre-intervention, and 0 and 45 minutes after intervention session (primary timepoint is 0 minutes after intervention).
Secondary outcome [1] 383129 0
Sitting pain, measured with a Patient Specific Functional Scale (PSFS)
Timepoint [1] 383129 0
Session 1 (orientation): baseline
Sessions 2 and 3: pre-intervention, and 24 hours after each intervention session
Secondary outcome [2] 387647 0
Steadiness of contraction using analysis of torque data from Biodex dynamometer
Timepoint [2] 387647 0
During isometric intervention session only
Secondary outcome [3] 387648 0
Victorian Institute of Sport - Hamstring (VISA-H) score
The VISA-H measures pain, function and sporting activity in people with PHT
Timepoint [3] 387648 0
Session 1: at start of session
Sessions 2 and 3: at start of session

Eligibility
Key inclusion criteria
Initial Phone Screening. Participants must meet all of the following criteria:
1. Reports of localised (defined as an area smaller than a tennis ball) ischial tuberosity region pain of gradual onset and at least 3 months in duration
2. Willingness to participate in three sessions of testing and intervention as part of the trial, over a 9 to 21 day period
3. Age between 18 and 60 inclusive
4. Fluency in English sufficient to complete questionnaires and to enable understanding to the intervention.
5. Agreeing to refrain from other interventions wherever possible for the treatment period of the trial, aside from consultation with medical practitioners and medication.
6. Agreeing to refrain from activity that would aggravate symptoms for 48 hours prior to each session.
Clinical examination screening
7. Positive findings (reproduction of lower buttock pain) with single leg arabesque AND with 2 or more of three additional diagnostic criteria:
o Supine single leg bridge with heel on standardised height platform (bent knee)
o Prolonged sitting >30 minutes
o Modified bent-knee hamstring stretch test (Cacchio, 2012)
(Symptoms must be >=2/10 with arabesque only)
8. A clear increase in activity levels precipitating onset of symptoms


A group of control participants without PHT are also being recruited. The inclusion criteria for this group is:
1. Willingness to participate in two sessions of testing and intervention as part of the trial, over a 3 to 7 day period
2. Age between 18 and 60 inclusive
3. Fluency in English sufficient to complete questionnaires and to enable understanding to the intervention.

Clinical examination screening
4. Negative findings (lower buttock pain) with single leg arabesque AND with all three additional diagnostic criteria:
o Supine single leg bridge with heel on standardised height platform (bent knee)
o Prolonged sitting >30 minutes
o Modified bent-knee hamstring stretch test (Cacchio, 2012)
(Symptoms must be >=2/10 with arabesque only)
Minimum age
18 Years
Maximum age
60 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Initial Phone Screening
1. Previous surgery to the hamstring complex, as we wish to study treatment effects independent to the effects of surgical procedures.
2. Previous injection to the hamstring tendon within the last 6 weeks, as we wish to study treatment effects independent to the effects of injections.
3. Previous imaging (MRI, Ultrasound) performed since onset of symptoms showing normal hamstring tendon appearance, as a radiologically normal tendon is unlikely to be pain generating.
4. Treatment with ESWT for PHT in the last 3 months, as we wish to study treatment effects independent to the effects of ESWT.
5. Current pregnancy, or recent childbirth (within 6 months) as this could impair ability to undertake testing and intervention.
6. Diagnosis with autoimmune disease as we do not wish to evaluate tendon response where there is a potential autoimmune influence
7. Previous imaging (MRI, ultrasound) showing perineural sciatic nerve oedema as this suggests a pain generator that is not the proximal hamstring tendon
Clinical examination screening
8. Pain that is predominantly due to lumbar dysfunction including lumbar spine radiculopathy, or lumbar spine somatic referral
9. Pain that is reasoned from clinical examination to be predominantly due to other structures or conditions, including sciatic nerve entrapment, ischiofemoral impingement, hip joint, local sciatic nerve irritation, and adductor magnus tendinopathy

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sequentially numbered sealed opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer generated block randomisation sequence, transferred to sealed opaque envelopes. .
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Sample size

We are aiming to recruit 40 participants (20 with PHT and 20 healthy controls) for this trial. As the first RCT to investigate the difference between isometric and isotonic strengthening for PHT, there was no precise data to guide sample size calculations. Trials relating to other tendinopathies have shown significant effects with similar or smaller sample sizes, while others have failed to show effects. In the absence of conclusive data relating to likely effects and variance in this population, combined with no data relating to feasibility of recruiting this population, a sample of 20 was therefore considered justified.

Data analysis

Analysis will focus on detecting the difference in outcomes following isometric versus isotonic treatment conditions. For pain and strength data, we will assess for normality using visual analysis of histograms and a Shapiro-Wilks test. An assumption of negligible carryover effects from the intervention will be evaluated using paired t tests to compare pain and VISA-H scores at the start of session 1 and 2 in each participant.
All analyses will be undertaken using repeated measures linear mixed models. Exercise type (isotonic vs isometric) and time (pre, immediately post, and 45 minutes post intervention) will be independent factors, with pain, strength and PSFS the dependent variables.
Further analyses will be undertaken to compare the proportion of patients who demonstrated a clinically relevant pain reduction following each intervention, using relative risks (with 95% confidence intervals), Chi-square testing, and Number Needed to Treat (NNT). We will define a clinically relevant difference in pain as 20 mm on a 100 mm VAS, or 2 points on the PSFS, for these analyses.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
30/11/2020
Actual
19/04/2021
Date of last participant enrolment
Anticipated
1/12/2022
Actual
Date of last data collection
Anticipated
12/12/2022
Actual
Sample size
Target
40
Accrual to date
14
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment postcode(s) [1] 30330 0
3083 - La Trobe University

Funding & Sponsors
Funding source category [1] 304100 0
University
Name [1] 304100 0
LaTrobe University
Country [1] 304100 0
Australia
Primary sponsor type
University
Name
LaTrobe University
Address
Plenty Rd & Kingsbury Dr, Bundoora VIC 3086
Country
Australia
Secondary sponsor category [1] 304315 0
None
Name [1] 304315 0
n/a
Address [1] 304315 0
n/a
Country [1] 304315 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 304588 0
La Trobe University Human Research Ethics Committee
Ethics committee address [1] 304588 0
Plenty Rd & Kingsbury Dr, Bundoora VIC 3086
Ethics committee country [1] 304588 0
Australia
Date submitted for ethics approval [1] 304588 0
26/02/2020
Approval date [1] 304588 0
14/05/2020
Ethics approval number [1] 304588 0
HEC20089

Summary
Brief summary
Proximal hamstring origin tendinopathy (PHT) is a common condition in the active and sporting population, particularly in sports involving sprinting, jumping, kicking or distance running. It was first described in 1988 (Puranen & Orava, 1988) as ‘Hamstring Syndrome’. The condition presents as localized lower buttock pain, and is typically aggravated by prolonged sitting, running or walking (particularly uphill), lunging and squatting.
The primary aim of this study is to compare the immediate effect of isometric and isotonic exercise on pain and strength in individuals with proximal hamstring tendinopathy.
A secondary aim of this study is to examine force steadiness in isometric contraction in a population with proximal hamstring tendinopathy compared to a matched population without the condition.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 97494 0
A/Prof Jon Ford
Address 97494 0
C/O LaTrobe University
Plenty Rd & Kingsbury Dr, Bundoora VIC 3086
Country 97494 0
Australia
Phone 97494 0
+61 422244183
Fax 97494 0
Email 97494 0
[email protected]
Contact person for public queries
Name 97495 0
Mr Aidan Rich
Address 97495 0
c/o Advance Healthcare Boronia
1/157 Scoresby rd Boronia Vic 3155
Country 97495 0
Australia
Phone 97495 0
+61 428506126
Fax 97495 0
Email 97495 0
[email protected]
Contact person for scientific queries
Name 97496 0
Mr Aidan Rich
Address 97496 0
c/o Advance Healthcare Boronia
1/157 Scoresby rd Boronia Vic 3155
Country 97496 0
Australia
Phone 97496 0
+61 428506126
Fax 97496 0
Email 97496 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Deidentified participant information data will be available including a/ Baseline demographic information, b/ Baseline Questionnaire information (on hamstring function), c/ strength and functional testing results, d/ strength intervention results, e/ symptoms after testing
When will data be available (start and end dates)?
Upon completion of trial, available with no end date.
Available to whom?
Only researchers who provide a methodologically sound proposal.
Available for what types of analyses?
Purpose as agreed to by the prinicipal investigator
How or where can data be obtained?
access subject to approvals by Principal Investigator, [email protected]


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
8027Study protocol    The study protocol will be submitted for publicati... [More Details]



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