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Trial registered on ANZCTR


Registration number
ACTRN12614001164684
Ethics application status
Approved
Date submitted
24/10/2014
Date registered
6/11/2014
Date last updated
3/06/2016
Type of registration
Prospectively registered

Titles & IDs
Public title
The effectiveness of quadriceps strengthening with and without blood flow restriction in the treatment of knee cap pain (patellofemoral pain)
Scientific title
The effectiveness of quadriceps strengthening with and without blood flow restriction in the treatment of patellofemoral pain
Secondary ID [1] 285537 0
Nil known
Universal Trial Number (UTN)
Nil
Trial acronym
Nil
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Patellofemoral pain 293354 0
Condition category
Condition code
Musculoskeletal 293629 293629 0 0
Other muscular and skeletal disorders
Physical Medicine / Rehabilitation 293691 293691 0 0
Physiotherapy

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The intervention group will perform Low intensity blood flow restriction training on the affected leg only.

This group will perform 15 minutes (total) of exercises on the stationary bicycle, leg press and leg extension. These exercises will be performed 3 times per week for 8 weeks.

The cycling will be for 5 minutes based at an intensity that the participant considers "light".

The blood flow restriction training group will perform exercises at 30 % of their maximum strength for 4 sets. The sets will consist of repetitions of 30, 15, 15 and 15. Each repetition will take 3 seconds, and there will be a 30 second rest between each set.

Physiotherapists will prescribe the exercises. The blood flow restriction will be applied using a pneumatic cuff with a handheld sphygmomanometer (width 10cm). The cuff will be applied to the proximal thigh. The cuff will be applied only for the leg press and leg extension exercises and will remain on between sets of exercises, but removed after the exercise is completed (cuff will remain on for approximately 4 minutes for leg press and 4 minutes for leg extension, with a 2 minute break between exercises with the cuff off).

Arterial occlusion pressure will be measured with Doppler ultrasound on initial assessment, by placing the ultrasound over the tibial artery at the ankle, and the cuff around the proximal thigh. The cuff will be inflated until the artery is occluded (this process is the equivalent of taking a blood pressure reading). The pressure of the cuff to be used during exercises will be 60% of the arterial occlusion pressure.

Participants will tick off which exercises were completed on each session in an exercise log to monitor adherence to the program.
Intervention code [1] 290485 0
Rehabilitation
Intervention code [2] 290530 0
Treatment: Other
Comparator / control treatment
The strengthening group (comparator group) will perform exercises prescribed by physiotherapists at 70 % of their maximum for 3 sets of 12 repetitions, or to volitional fatigue. With a 30 second rest between sets.

This group will perform 15 minutes (total) of exercises on the stationary bicycle, leg press and leg extension. These exercises will be performed 3 times per week for 8 weeks.

The cycling will be for 5 minutes at an intensity that the participant considers "light". Leg press and leg extension will each take approximately 4 minutes to complete, and there will be a 2 minute rest between exercises.

Participants will tick off which exercises were completed on each session in an exercise log to monitor adherence to the program.
Control group
Active

Outcomes
Primary outcome [1] 293444 0
Patellofemoral pain (VAS), worst pain in the past week. 100mm scale.
Timepoint [1] 293444 0
4, 8, and 24 weeks.
Primary outcome [2] 293445 0
Nil
Timepoint [2] 293445 0
4, 8 and 24 weeks.
Primary outcome [3] 293529 0
Kujala anterior knee pain scale- measures of patellofemoral pain and function.
Timepoint [3] 293529 0
4, 8 and 24 weeks
Secondary outcome [1] 311068 0
Quadriceps muscle size- measured with real time ultrasound as muscle thickness (cm) at the mid thigh and distal thigh.
Timepoint [1] 311068 0
0 and 8 weeks
Secondary outcome [2] 311181 0
Isometric quadriceps muscle strength measured with a Humac Dynamometer at 60 degrees of flexion.
Timepoint [2] 311181 0
0 and 8 weeks
Secondary outcome [3] 324474 0
Global rating of change in pain, rated as 1. Much worse, 2. Worse, 3. Same, 4. Improved, 5. Much Improved
Timepoint [3] 324474 0
24 weeks
Secondary outcome [4] 324475 0
Patellofemoral pain with daily activity (VAS). Worst pain with squatting, stairs, or prolonged sitting on a 100mm scale.
Timepoint [4] 324475 0
4, 8, and 24 weeks

Eligibility
Key inclusion criteria
Pain at the front of the knee for 8 weeks or longer
Atraumatic onset of symptoms
Pain with any two of running, squatting, prolonged sitting, jumping, kneeling.
Minimum age
18 Years
Maximum age
40 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Knee ligament injury, knee surgery, dislocation/subluxation Inflammatory arthritis
Participated in strengthening exercises with leg weights for longer than 4 weeks in the past 6 months.

Cardiovascular conditions, including high blood pressure (>140/90), diabetes, unexplained chest pain or heart condition, fainting or dizzy spells during physical activity/exercise that causes loss of balance, pregnancy or other contra-indications to exercise.

Conditions affecting blood flow or blood clotting

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)
Subjects responding to posters in sports medicine clinics, or online call or email the investigator.

Participants will be screened by phone and on presentation to the testing room to determine if they are eligible to participate.

Allocation will be done off site by an independent person who has been assigned this role.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A random number generator will be used with Microsoft Excel
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
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
SPSS will be used for all statistical analysis (statistical significance P<.05). One way ANOVA will be used to assess if differences are present at baseline between groups for age, gender, body mass index (BMI) and symptom duration.

To determine group differences over time Repeated Measures Analysis of variance (ANOVAs) or Generalised Estimating Equations will be performed for scores on pain(visual analogue scale (VAS)), and function (Kujala anterior knee pain scale), quadriceps muscle strength and quadriceps muscle thickness at 0, and 8 weeks; VAS and Kujala anterior knee pain scale will also be assessed at 4, 24 and 52 weeks.

Power analysis with G Power suggested 70 participants were required to detect a large effect size between the groups. Significance <.05. alpha error prob 0.95.



Recruitment
Recruitment status
Active, not 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 in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 290146 0
University
Name [1] 290146 0
La Trobe University Lower Extremity and Gait Studies
Address [1] 290146 0
La Trobe University, Bundoora, Vic, 3086
Country [1] 290146 0
Australia
Primary sponsor type
Individual
Name
Lachlan Giles
Address
Department of physiotherapy, La Trobe University, Bundoora, Vic, 3086
Country
Australia
Secondary sponsor category [1] 288855 0
Individual
Name [1] 288855 0
Kate Webster
Address [1] 288855 0
Department of occupational therapy, School of Allied Health, La Trobe University, Bundoora, Vic, 3086
Country [1] 288855 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 291854 0
La Trobe University Faculty Human Ethics Committee
Ethics committee address [1] 291854 0
La Trobe University, Bundoora, Vic 3086
Ethics committee country [1] 291854 0
Australia
Date submitted for ethics approval [1] 291854 0
Approval date [1] 291854 0
25/09/2014
Ethics approval number [1] 291854 0
14/200

Summary
Brief summary
Patellofemoral pain is common in people who participate in activities and sports that involve running. Improved treatment outcomes in patellofemoral pain are required as recent research has established a link between patellofemoral pain and future osteoarthritis of the knee. Common interventions such as quadriceps strengthening exercises are effective at reducing pain for many people with patellofemoral pain.

Quadriceps strengthening is likely to have an effect in improving patellofemoral pain because of resultant increases in quadriceps size and strength. However some people with patellofemoral pain are unable to perform exercises with a resistance that significantly strengthens the quadriceps because pain limits their ability to perform the exercises. Blood flow restricted training can increase muscle size and strength at lower resistance than typical strengthening programs, and may therefore be a suitable method of improving quadriceps size and strength in those unable to perform traditional quadriceps strengthening exercises effectively.

Blood flow restricted training involves placing an inflatable cuff around a limb before performing strengthening exercises. The placement of the cuff reduces blood flow within the limb during the exercise. It is hypothesised that limited blood flow causes the muscle to work harder than in normal blood flow conditions, and therefore improvements in muscle size and strength can be obtained at lower resistance than conventional exercises.


This study will compare 8 weeks of low resistance quadriceps strengthening with blood flow restriction to the current gold standard treatment of 8 weeks of quadriceps strengthening. Participants will be assessed at 0, 4, 8, 24 and 52 weeks.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 52262 0
Mr Lachlan Giles
Address 52262 0
Department of Physiotherapy, La Trobe University, Bundoora, Vic, 3086
Country 52262 0
Australia
Phone 52262 0
+61394795871
Fax 52262 0
Email 52262 0
lsgiles@students.latrobe.edu.au
Contact person for public queries
Name 52263 0
Mr Lachlan Giles
Address 52263 0
Department of Physiotherapy, La Trobe University, Bundoora, Vic, 3086
Country 52263 0
Australia
Phone 52263 0
+61394795871
Fax 52263 0
Email 52263 0
lsgiles@students.latrobe.edu.au
Contact person for scientific queries
Name 52264 0
Mr Lachlan Giles
Address 52264 0
Department of Physiotherapy, La Trobe University, Bundoora, Vic
Country 52264 0
Australia
Phone 52264 0
+61394795871
Fax 52264 0
Email 52264 0
lsgiles@students.latrobe.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary