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Trial registered on ANZCTR


Registration number
ACTRN12609000678291
Ethics application status
Approved
Date submitted
5/08/2009
Date registered
10/08/2009
Date last updated
24/07/2013
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effect of femoral head size on dislocation following total hip replacement
Scientific title
The effect of a large 36 mm vs standard 28 mm articulation in a total hip prosthesis on the incidence of dislocation one year following total hip replacement
Secondary ID [1] 282899 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
dislocation following total hip replacement 243460 0
Condition category
Condition code
Musculoskeletal 239759 239759 0 0
Osteoarthritis
Musculoskeletal 239760 239760 0 0
Other muscular and skeletal disorders
Surgery 239761 239761 0 0
Surgical techniques

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Total hip replacement using a 36 mm metal on highly cross-linked polyethylene articulation. This is a surgical procedure where the femoral head is removed and replaced by a metal prosthetic femoral head (which in this situation has a diameter of 36 mm), which is attached to a femoral stem inserted into the femur. The head then articulates with a plastic (highly cross-linked polyethylene) liner in a metal acetabular shell, which is inserted into the acetabulum. The duration of the operation is between about 45 minutes and 4 hours, depending on the complexity of the operation.
Intervention code [1] 237074 0
Treatment: Surgery
Comparator / control treatment
Total hip replacement using a 28 mm metal on highly cross-linked polyethylene articulation. This is a surgical procedure where the femoral head is removed and replaced by a metal prosthetic femoral head (which in this situation has a diameter of 28 mm), which is attached to a femoral stem inserted into the femur. The head then articulates with a plastic (highly cross-linked polyethylene) liner in a metal acetabular shell, which is inserted into the acetabulum. The duration of the operation is between about 45 minutes and 4 hours, depending on the complexity of the operation.
Control group
Active

Outcomes
Primary outcome [1] 240522 0
Dislocation of the total hip prosthesis.
Patients complete a Hip Instability Questionnaire, which asks whether they have experienced a number of symptoms of instability or a dislocation. A Hospital Visit Questionnaire is also completed, which documents every admission or attendance to the Emergency Room of a hospital.
A radiograph of the dislocated hip is required for confirmation of dislocation.
Timepoint [1] 240522 0
one year following total hip replacement
Secondary outcome [1] 257076 0
Polyethylene wear, which is measured from standard radiographs, using PolyWare, a computer-based analysis program for measuring wear.
Timepoint [1] 257076 0
two years following total hip replacement
Secondary outcome [2] 257077 0
Acetabular cup migration, which is measured from standard radiographs, using Einbild Roentgen Analyse (EBRA), a computer-based analysis program for measuring acetabular cup migration.
Timepoint [2] 257077 0
two years following total hip replacement

Eligibility
Key inclusion criteria
undergoing primary total hip replacement involving a metal on polyethylene articulation, through a posterior surgical approach, for osteoarthritis, rheumatoid or other inflammatory arthritis, or previous fracture/dislocation/surgery to the hip; or
undergoing revision total hip replacement (involving a metal on polyethylene articulation) of a hemiarthroplasty or revision of a total hip replacement
Minimum age
50 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
age <60 years (revisions: <50),
neuromuscular disease,
abnormal abductor mechanism,
abnormal acetabulum (primaries only),
revision for instability or infection (revisions only)

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)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A listing of all possible combinations of allocations in blocks of 2 to 8 was prepared (eg for a block of 4: 28,28,36,36; 36,36,28,28, 36,28,36,28 etc) and each combination was allocated a number. Then a random number generator was used to choose the combination sequence for the block sizes required in each stratum.
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Patients are stratified for a number of factors that may affect primary and secondary outcomes (eg age, diagnosis).
Blocked randomisation is then undertaken within strata, with patients being randomised to receive a total hip prosthesis with either a 28 mm or 36 mm articulation.
Phase
Type of endpoint(s)
Efficacy
Statistical methods / analysis

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)
NSW,SA,VIC
Recruitment outside Australia
Country [1] 1934 0
United Kingdom
State/province [1] 1934 0

Funding & Sponsors
Funding source category [1] 237453 0
Government body
Name [1] 237453 0
National Health Medical Research Council (NHMRC)
Address [1] 237453 0
Level 1,
16 Marcus Clarke St
Canberra ACT 2601
Country [1] 237453 0
Australia
Funding source category [2] 237454 0
Commercial sector/Industry
Name [2] 237454 0
Zimmer
Address [2] 237454 0
1800 W Center St
Warsaw IN 46580
Country [2] 237454 0
United States of America
Funding source category [3] 237455 0
University
Name [3] 237455 0
University of Adelaide
Address [3] 237455 0
North Tce
Adelaide SA 5005
Country [3] 237455 0
Australia
Funding source category [4] 237456 0
Hospital
Name [4] 237456 0
Royal Adelaide Hospital
Address [4] 237456 0
North Tce
Adelaide SA 5000
Country [4] 237456 0
Australia
Funding source category [5] 237457 0
Other Collaborative groups
Name [5] 237457 0
Australian Orthopaedic Association
Address [5] 237457 0
Ground Floor
William Bland Centre
229 Macquarie St
Sydney NSW 2000
Country [5] 237457 0
Australia
Primary sponsor type
Individual
Name
Prof Donald Howie
Address
Department of Orthopaedics and Trauma
Level 4, Bice Building
Royal Adelaide Hospital
North Tce
Adelaide SA 5000
Country
Australia
Secondary sponsor category [1] 236942 0
Individual
Name [1] 236942 0
Dr Oksana Holubowycz
Address [1] 236942 0
Department of Orthopaedics and Trauma
Level 4, Bice Building
Royal Adelaide Hospital
North Tce
Adelaide SA 5000
Country [1] 236942 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 239580 0
Royal Adelaide Hospital Human Research Ethics Committee
Ethics committee address [1] 239580 0
Royal Adelaide Hospital
North Tce
Adelaide SA 5000
Ethics committee country [1] 239580 0
Australia
Date submitted for ethics approval [1] 239580 0
Approval date [1] 239580 0
Ethics approval number [1] 239580 0

Summary
Brief summary
This randomised controlled trial aims to determine whether a total hip replacement with a larger 36 mm diameter prosthetic femoral head significantly reduces the incidence of dislocation one year following total hip replacement, compared to total hip replacement with a standard 28 mm diameter prosthetic femoral head. The effect of the larger femoral head on both polyethylene wear and acetabular cup migration is also being assessed.
Trial website
Trial related presentations / publications
Howie DW, Holubowycz OT, Middleton R, The Large Articulation Study Group. Large femoral heads decrease the incidence of dislocation after total hip arthroplasty. A randomized controlled trial. J Bone Joint Surg Am. 2012;94:1095-102.
Public notes

Contacts
Principal investigator
Name 30012 0
Prof Donald Howie
Address 30012 0
Department of Orthopaedics and Trauma
Level 4, Bice Building,
Royal Adelaide Hospital
North Tce
Adelaide SA 5000
Country 30012 0
Australia
Phone 30012 0
+61 8 8222 5563
Fax 30012 0
Email 30012 0
donald.howie@health.sa.gov.au
Contact person for public queries
Name 13259 0
Dr Dr Oksana Holubowycz
Address 13259 0
Department of Orthopaedics and Trauma
Level 4, Bice Building
Royal Adelaide Hospital
North Tce
Adelaide SA 5000
Country 13259 0
Australia
Phone 13259 0
+61 8 8222 5760
Fax 13259 0
Email 13259 0
oksana.holubowycz@health.sa.gov.au
Contact person for scientific queries
Name 4187 0
Dr Dr Oksana Holubowycz
Address 4187 0
Department of Orthopaedics and Trauma
Level 4, Bice Building
Royal Adelaide Hospital
North Tce
Adelaide SA 5000
Country 4187 0
Australia
Phone 4187 0
+61 8 8222 5760
Fax 4187 0
Email 4187 0
oksana.holubowycz@health.sa.gov.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