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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
Comparison of three approaches for primary Total Hip Arthroplasty
Scientific title
Comparison of outcome measures and complication rates following three different approaches for primary Total Hip Arthroplasty. A pragmatic randomised controlled trial.
Secondary ID [1] 291022 0
nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis 301807 0
Condition category
Condition code
Musculoskeletal 301490 301490 0 0
Surgery 301657 301657 0 0
Surgical techniques

Study type
Description of intervention(s) / exposure
Primary Total Hip Arthroplasty (THA) will be compared using three different surgical approaches. Anterior, Lateral and Posterior. Each approach has approximately the same surgical time of 90-120 minutes.

Posterior Approach:
This approach is the most common approach for THA worldwide today, made popular by Moore in 1959. This approach also allows excellent visualisation of the femoral shaft but involves detachment of the short external rotators of the hip with a posterior capsulotomy.
Hardinge Approach:
This was first described by Hardinge in 1982. This approach requires the reflection of gluteus medius and minimus muscles off the greater trochanter.
Anterior Approach:
Initial description of this approach to the hip joint was by Smith-Petersen. It utilises the anatomic internervous plane between the superior gluteal nerve laterally and femoral nerve medially and has recently been popularised for THR, but it’s first reported use dates back to 1947 in France by Judet and colleagues.

Patients will be randomised to surgical approach for THA.
Each consultant surgeon will perform the approach which is their usual standard of care.
Pre-operatively and post-operatively PROMs (OHS, VAS) will be taken at 6 weeks, 6, 12 and 24 months.
Complications will be monitored, specifically dislocation, infection and revision.
Intervention code [1] 296995 0
Treatment: Surgery
Comparator / control treatment
This is a three-arm randomised controlled trial. Three arms will be compared directly.
The null hypothesis is that there will be no difference between approaches.
It is not possible to use one approach as the surgical control.
Control group

Primary outcome [1] 300883 0
Patient reported outcome measures (Oxford Hip Score)
Timepoint [1] 300883 0
6 weeks, 6 months, 12 months and 24 months post THA
Primary outcome [2] 301050 0
Visual Analogue Scale for pain
Timepoint [2] 301050 0
Pre-operatively then 6 weeks, 6, 12 and 24 months post-operatively
Secondary outcome [1] 331111 0
Residual pain - using Visual Analogue Scale and locating site of pain (trochanteric, gluteal or groin)
Complications including dislocation, infection, revision - defined by complication recorded in the medical record, return to theatre or patient reports complication occurring on follow up questioning.
Timepoint [1] 331111 0
6 weeks, 6 months, 12 months and 24 months post THA

Key inclusion criteria
Primary osteoarthritis of the hip requiring total hip replacement
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Prior bony procedures on hip
Indication for THA is fracture, malignancy or developmental dysplasia

Study design
Purpose of the study
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)
Masking / blinding
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint/s
Statistical methods / analysis
The null hypothesis for this study is that patient reported outcomes following three different approaches for THA are no different when directly compared after 24 months post-procedure. In addition we hypothesise that complication rates are the same between approaches. There is no randomised controlled trial that directly compares these three approaches for THA. We are hence designing our study as a superiority study looking for a significant difference in OHS and VAS between the different trial arms.

The randomization list will be computer-generated by an independent statistician. A stratified block permuted randomization will be used with the Kellgren-Lawrence grading scale (grade 0-2 vs. grade 3-4) as the stratification variable. The block size will not be disclosed to ensure concealment. Randomization will be enabled through a secure, web-based application.
The trial investigators will perform patient enrolment and random assignment. Patients will be randomised to one of three operative types within the patient’s Kellgren-Lawrence grading stratum.

The nine surgeons performing the operation will be assigned to an operation type according to their expertise. Each surgeon will perform a single operation type and each operation type will be conducted by three surgeons.
A patient will be managed by one of the three surgeons corresponding to the treatment group the patient is randomly assigned to with the actual surgeon depending on the surgeons’ roster at the time the patient presents him/herself for the operation. It is anticipated that each surgeon will treat roughly the same number of patients
The study will enrol a total of 243 patients to be treated by nine orthopaedic surgeons at Western Health or 81 patients per operation type.

The primary hypothesis will be examined by three contrasts evaluating the change from pre-operation to 24 months post-procedure in OHS overall score for the posterior versus Hardinge approach, the posterior versus anterior approach, and the Hardinge versus anterior approach using an alpha level of 1.67% for each contrast to allow for the three comparisons. The primary hypothesis will be rejected if at least one of the three comparisons reaches statistical significance using the two-sided Holm-Bonferroni-adjusted alpha level. An estimate and corresponding two-sided multiplicity-adjusted 98.33% confidence interval will be provided for each comparison. This analysis method uses a model-based approach to handle missing data providing valid inference if the missing data mechanism is ignorable (i.e., missing completely at random or missing at random). A range of sensitivity analyses to examine the robustness of the primary model results will be performed to explore the impact of the results of different missing data techniques under the same and under different missingness assumptions.

Recruitment status
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 hospital [1] 7394 0
Western Hospital - Footscray
Recruitment postcode(s) [1] 15189 0
3011 - Footscray

Funding & Sponsors
Funding source category [1] 295450 0
Name [1] 295450 0
Western Health Orthopaedic Department
Country [1] 295450 0
Primary sponsor type
Western Health
Level 1 South,
Footscray Hospital
Gordon St,
Footscray VIC 3011
Secondary sponsor category [1] 294272 0
Name [1] 294272 0
Address [1] 294272 0
Country [1] 294272 0

Ethics approval
Ethics application status
Ethics committee name [1] 296782 0
Melbourne Health HREC
Ethics committee address [1] 296782 0
Office for Research
The Royal Melbourne Hospital Level 2 South West
300 Grattan Street
Parkville VIC 3050
Ethics committee country [1] 296782 0
Date submitted for ethics approval [1] 296782 0
Approval date [1] 296782 0
Ethics approval number [1] 296782 0

Brief summary
This is a project analysing three surgical approaches for the same orthopaedic procedure, total hip arthroplasty (THA).
This study will be conducted as a pragmatic randomised controlled trial comparing three approaches to the hip joint for this procedure – anterior, posterior and direct lateral (Hardinge) approaches.
The null hypothesis is there will be no difference in outcomes between three approaches in terms of patient satisfaction with the procedure. We will measure this via validated scores: patient reported outcome measures (PROMs).
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 72038 0
Mr Phong Tran
Address 72038 0
Orthopaedic Department
Level 1 South
Footscray Hospital
Gordon Street, Footscray VIC 3011
Country 72038 0
Phone 72038 0
Fax 72038 0
Email 72038 0
Contact person for public queries
Name 72039 0
Ms Libby Spiers
Address 72039 0
Orthopaedic Department
Level 1 South
Footscray Hospital
Gordon Street, Footscray VIC 3011
Country 72039 0
Phone 72039 0
Fax 72039 0
Email 72039 0
Contact person for scientific queries
Name 72040 0
Dr Adrian Talia
Address 72040 0
Orthopaedic Department
Level 1 South
Footscray Hospital
Gordon Street, Footscray VIC 3011
Country 72040 0
Phone 72040 0
Fax 72040 0
Email 72040 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
Not relevant at this early stage

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.