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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Jumper's knee: does exercise decrease pain and increase participation in basketball?
Scientific title
Isometric and isotonic leg extensions program: does either exercise decrease morbidity of patellar tendinopathy in basketball players when performed regularly during a playing season?
Secondary ID [1] 289274 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Patellar tendinopathy 298859 0
Condition category
Condition code
Musculoskeletal 298927 298927 0 0
Other muscular and skeletal disorders

Study type
Description of intervention(s) / exposure
The intervention exercises will be conducted four times per week at participants usual training session with equipment provided by the investigators. Players can do their exercise before or after training.
The exercise program will be individualised and delivered electronically to participants with exercise prescription software. the repetitions and sets will be consistent in all participants, the weight will be individualised to each participant and to each leg of each participant to account for differences in muscle strength. Participants will record on the software the number of times each week they complete the session and the weights that they use for the exercise session.
The intervention will be offered for the length of the season, this can vary between 6 and 10 months depending on the competition and the country.
Isometric protocol: Participants will complete isometric holds on a leg extension machine. These consist of 5 x 45 second holds at 70% maximum voluntary contraction (MVC) with 2 minutes recovery between holds.
Isotonic protocol: Participants will complete the isotonic exercise on a leg extension machine using established protocols (4 x 8 contractions at 70% MVC). The rest period between sets will be 1 minute.
Intervention code [1] 294823 0
Treatment: Other
Comparator / control treatment
The isotonic group will serve as the control group,
Control group

Primary outcome [1] 298391 0
OSTRC outcome measure. This validated tool measures that includes 4 simple questions,quantifies the impact of overuse injuries on function and is used for all overuse injuries.
Timepoint [1] 298391 0
Monthly for the length of the season, this will vary depending on country and league and will be between 6 and 10 months.
Primary outcome [2] 298393 0
VISA-P that assesses the amount of pain and dysfunction in people with anterior knee pain. The questions are designed to measure symptoms of jumper's knee, but the questionnaire is not diagnostic.
Timepoint [2] 298393 0
Monthly for the length of the season, this will vary depending on country and league and will be between 6 and 10 months.
Primary outcome [3] 298396 0
Participants will complete a global rating of change in knee pain and function on a seven point scale from very much worse to very much better.
Timepoint [3] 298396 0
End of the competitive season that will be between 6 and 10 months after the start of the intervention depending on the competition level and country.
Secondary outcome [1] 324019 0
The change in the amount of patellar tendon pathology will be assessed using UTC tendon imaging.
Timepoint [1] 324019 0
End of the competitive season that will be between 6 and 10 months after the start of the intervention depending on the competition level and country.

Key inclusion criteria
1. Have current or previous patellar tendinopathy
2. Playing basketball at an elite or semi-elite level that will ensure they are training more than 4 times a week.
3. Over 18 years until they are no longer playing at an elite or sub-elite level, this is usually up to 35 years but occasionally players can be older
Minimum age
18 Years
Maximum age
35 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Insufficient English language ability to understand informed consent and follow study protocol .

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sealed opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Whole teams will be block randomised to one intervention
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
Generalised estimating equation (group and time)
Previous study (van Ark et al 2015) showed improvement with both exercise interventions, to show a difference between exercise interventions with an alpha of .05 and a beta of >8 128 participants will be required.

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment outside Australia
Country [1] 7892 0
United States of America
State/province [1] 7892 0
Wshington DC. Milwaukee, Tulane, Louisiana, New York

Funding & Sponsors
Funding source category [1] 293654 0
Commercial sector/Industry
Name [1] 293654 0
NBA/GE Orthopaedics and Sports Medicine collaboration
Address [1] 293654 0
General Electric Healthcare
43614 Westridge Lane
Northville, MI 48167 USA
Country [1] 293654 0
United States of America
Primary sponsor type
La Trobe university
Kingsbury Drive
Bundoora 3086
Secondary sponsor category [1] 292490 0
Name [1] 292490 0
Address [1] 292490 0
Country [1] 292490 0

Ethics approval
Ethics application status
Ethics committee name [1] 295091 0
La Trobe university Human ethics committee
Ethics committee address [1] 295091 0
Kingsbury Drive
3086 Victoria Australia
Ethics committee country [1] 295091 0
Date submitted for ethics approval [1] 295091 0
Approval date [1] 295091 0
Ethics approval number [1] 295091 0

Brief summary
The impact of patellar tendinopathy is underestimated as many athletes continue to participate with pain that affects performance in games and capacity to train. This study aims to determine if we can change the natural history of pain and impaired performance with exercise;

Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 66086 0
Prof Jill Cook
Address 66086 0
La Trobe University
Kingsbury Drive
3086, Victoria, Australia
Country 66086 0
Phone 66086 0
+61 3 94792774
Fax 66086 0
Email 66086 0
Contact person for public queries
Name 66087 0
Prof Jill Cook
Address 66087 0
La Trobe University
Kingsbury Drive
3086, Victoria, Australia
Country 66087 0
Phone 66087 0
+61 3 94792774
Fax 66087 0
Email 66087 0
Contact person for scientific queries
Name 66088 0
Prof Jill Cook
Address 66088 0
La Trobe University
Kingsbury Drive
3086, Victoria, Australia
Country 66088 0
Phone 66088 0
Fax 66088 0
Email 66088 0

No information has been provided regarding IPD availability
Summary results
No Results