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Trial registered on ANZCTR


Registration number
ACTRN12617000063314
Ethics application status
Approved
Date submitted
17/10/2016
Date registered
12/01/2017
Date last updated
15/11/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Comparison of patient outcomes following total hip arthroplasty via an anterior or posterior approach: a prospective randomised controlled trial
Scientific title
Comparison of patient outcomes following total hip arthroplasty via an anterior or posterior approach: a prospective randomised controlled trial
Secondary ID [1] 290344 0
Nil
Universal Trial Number (UTN)
Trial acronym
PATHRS
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis 300622 0
Condition category
Condition code
Surgery 300467 300467 0 0
Surgical techniques
Musculoskeletal 300498 300498 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Comparison of a surgical approach for total hip replacement surgery. Participants will be randomised into 2 groups Group 1 posterior approach to total hip replacement performed by an orthopaedic consultant surgeon and Group 2 anterior approach to total hip replacement performed by an orthopaedic consultant surgeon.
Intervention code [1] 296158 0
Treatment: Surgery
Comparator / control treatment
Comparison of a surgical approach for total hip replacement surgery. Participants will be randomised into 2 groups Group 1 posterior approach to total hip replacement performed by an orthopaedic consultant surgeon and Group 2 anterior approach to total hip replacement performed by an orthopaedic consultant surgeon.
Control group
Active

Outcomes
Primary outcome [1] 299903 0
length of hospital stay assessed by review of medical records.

Timepoint [1] 299903 0
12 months post procedure
Secondary outcome [1] 330627 0
Rate of complications, including surgical and medical complications.
Participants will be assessed for complications at time of surgery, and at each post operative review.
Timepoint [1] 330627 0
3,6,12 months post procedure
Secondary outcome [2] 330664 0
Dislocation via symptoms of pain and immobility and radiology
Timepoint [2] 330664 0
3,6,12 months at out patient review
Secondary outcome [3] 340565 0
Requirement of blood transfusions. The number of transfusions will be documented from the medical chart of the participant 2 weeks after discharge.
Timepoint [3] 340565 0
2 weeks
Secondary outcome [4] 340566 0
Estimated Blood loss. Estimated blood loss is calculated at time of surgery by assessing amount of blood in suction canister, along with number of soaked sponges/raytecs to give an estimate.
Timepoint [4] 340566 0
Time of surgery
Secondary outcome [5] 340567 0
Pain (via VAS)
Timepoint [5] 340567 0
Day 1, Day 2 post op, 2 weeks, 6 weeks, 3 months, 6 months, 12 months
Secondary outcome [6] 340568 0
Analgesia requirement. All medications given during hospital admission are recorded in the medical record. The total opioid analgesia requirement will be determined by converting opioid medications to equivalent oral morphoine dose.
Post hospital discharge, participants will be required to record analgesia taken in a study participant diary.
Timepoint [6] 340568 0
Day 1 and 2 post op.
1,2, and 6 weeks post op.
3 months post op
Secondary outcome [7] 340569 0
Mobility at discharge. Less requirement for an aide suggest improved post operative recovery.
Mobility is assessed as:
- requiring no aides
- requiring single point stick
- requiring 4wheeled walker
- requiring hopper frame
- wheelchair bound.
Timepoint [7] 340569 0
Discharge from hospital
Secondary outcome [8] 340570 0
Discharge destination
Timepoint [8] 340570 0
Discharge from hospital
Secondary outcome [9] 340571 0
28-day hospital re-admission. Any presentation to emergency departments, or readmission to hospital is considered a positive result. Assessment is via direct questioning of participant and checking presentations to QLD Health facilities via use of 'The viewer" medical application.
Timepoint [9] 340571 0
4 weeks post operative
Secondary outcome [10] 340572 0
Harris Hip score
Timepoint [10] 340572 0
The score will be administered pre-operatively, and post-operatively at three, six and 12 months post-operatively.
Secondary outcome [11] 340573 0
Oxford Hip Score
Timepoint [11] 340573 0
The OHS will be administered pre-operatively, and at three, six and 12 months post-operatively.
Secondary outcome [12] 340574 0
EuroQol 5 dimension (EQ-5D) Quality of life outcome measure
Timepoint [12] 340574 0
The EQ-5D will be administered pre-operatively, and at three, six and 12 months post-operatively
Secondary outcome [13] 340575 0
Rate of secondary interventions. Secondary intervention is defined as a further operation related to the primary total hip arthroplasty. It will be assessed via review of medical records.
Timepoint [13] 340575 0
Assessed at 2 and 6 weeks post-operatively, then 3 months, 6 months, 12 months and 2 years.
Secondary outcome [14] 340576 0
Post-operative step count. Activity will be monitored with a fibit® zip activity monitor which will be given to each participant at initial contact. Participants will be instructed to wear the pedometer for the entirety of the week prior to operation, and for six weeks post-operatively. Data from the fibit® zip activity monitor will be downloaded at the six week post-operative review.
The post-operative step count will be compared between treatment groups.
Timepoint [14] 340576 0
6 weeks
Secondary outcome [15] 340577 0
Radiographic positioning of components.
Assessment of positioning of implants and leg length discrepancy will be performed by a senior orthopaedic surgeon and radiologist not involved in the surgical care of participants in the study using EOS biplanar radiography at six months post surgical intervention. EOS is a low-dose bi-planar radiography system that has been shown to be more accurate than CT and conventional radiographs in the assessment of leg length, and has successfully been used to measure leg length and offset following THA. The assessor will be blinded to participant treatment group. All images will be viewed via Picture Archiving and Communication System (PACS) using AFGA IMPAX v 6.5.3.1005 software. Acetabular components will be assessed for inclination and anteversion and measured to the nearest degree. Femoral components will be assessed for stem orientation and classified as valgus, neutral or varus.
Timepoint [15] 340577 0
6 months
Secondary outcome [16] 340578 0
Hip muscle volume.
Hip muscle volume and adiposity will be assessed via 3T Magnetic Resonance Imaging (MRI) scanner. Capturing high resolution fat and water images will enable the quantification of adiposity within a muscle, as has been performed by members of our team previously. An estimate of muscle volume for gluteus minimus, medius, maximus, tensor fascia lata and rectus femoris will be obtained from MRI scans as described previously (good inter-rater reliability ICC=0.80-0.98). De-identified images will be stored on a CD for offline processing, where the fascial border of each muscle will be traced manually in each axial slice using MATLAB (The MathWorks, Inc, Natick, MA); then summed to estimate muscle volume. The final estimate will be normalized to bodyweight. Due to artefact from the THR prosthesis, volume estimates are unreliable for gluteus minimus, so only measures of cross-sectional area will be obtained from this muscle at one-third the distance between the iliac crest and the greater trochanter.
Timepoint [16] 340578 0
6 months
Secondary outcome [17] 340579 0
Isometric Hip strength.
Isometric hip strength of all participants will be assessed with hand-held dynamometry.
Timepoint [17] 340579 0
pre-operatively and 6 months post-operatively
Secondary outcome [18] 340580 0
Spatio-temporal gait parameters.
This is a composite test.
Spatio-temporal gait parameters including walking speed, cadence and stride-length will be recorded using a GAITRite® walkway (Electronic Walkway, CIR Systems Inc., USA).
Timepoint [18] 340580 0
Pre-operatively, and 6 months post-operatively
Secondary outcome [19] 340581 0
Physical function testing. This is a composite testing battery.
Physical function tests recommended for hip osteoarthritis including; 30 sec chair stand test (number of sit-to stands performed in 30 seconds, 40 metre fast paced walk; and stair climb test.
Timepoint [19] 340581 0
pre-operatively, and 6 months post-operatively
Secondary outcome [20] 340582 0
Hip muscle adiposity.
Adiposity will be quantified with MRI. We will use an established 3D multi-echo gradient echo acquisition, which collects the data required for the analysis of phase related to the precessional differences in fat and water. This technique has been validated with the gold standard, biopsy. A muscle-fat index will be calculated as the proportion of fat to total muscle (fat/fat+muscle). This will be quantified at three sites along the length of each muscle based on previous qualitative adiposity gradings of the hip. Given the segmental nature of gluteus minimus and gluteus medius, this value will be determined for two separate segments of gluteus medius and minimus (anterior and posterior). A customized program has been developed by this research team to process these images with MATLAB (The MathWorks, Inc, Natick, MA).
Timepoint [20] 340582 0
6 months

Eligibility
Key inclusion criteria
Age greater than 50 years
Osteoarthritis requiring total hip arthroplasty
Provision of informed consent
Minimum age
50 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. condition other than osteoarthritis as reason for requiring THR
2. Patient with significant injuries on ipsilateral limb affecting treatment and rehabilitation
3. Retained metalware of affected acetabulum/proximal femur
4. Pre-existing neurological deficit of limb
5. Pregnancy
6. Insufficient English Proficiency to give informed consent
7. Cognitive impairment impeding ability to give informed consent

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)
Patients consenting to participate in the trial will be randomized to either DAA or PA, and will be allocated via the sequence generation as stated in the appropriate section. sealed opaque envelopes will hold the relevant sequences for each stratum.

Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomization sequence will be generated by an independent study coordinator with no additional involvement in the study. The sequence will be stratified by age (50-74 years and >74 years) and BMI (<35 and 35 and over) and allocated in random blocks of two, six, and eight.
For example, a patient with BMI of 35 would be in the 35 and over category.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


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
A sample size was calculated using the primary outcome of length of hospital stay. Malek et al. reported a LOS following DAA with mean of 3.7 (estimated SD 1.2) and a LOS following PA with mean of 4.2 (estimated SD 1.0). Using a 2 sample, 2-sided t-test, with a power of 80% and a significance value of 0.05, a sample size of 78 in each study group was determined. To account for missing values and clinical effects, an annual attrition rate of 10% per year is assumed, which inflates the sample size to 98 participants in each group which we further round up to 100 participants per group.

All data will be manually extracted from the patient record and entered into a password protected excel database. The data will be cleaned and then coded for statistical analysis Data will be analysed using the Statistical Package for Social Sciences (SPSS) version 22.0. Data will be reported on following CONsolidated Standards Of Reporting Trials (CONSORT) guidelines.
Baseline characteristics will be assessed for differences between treatment groups. Normality of continuous data will be assessed by a Komogorov-Smirnov test. Continuous nonparametric data will be assessed via the Mann-Whitney U test. Continuous parametric data will be assessed with the Students’ t-test. Nominal and categorical data will be assessed with Fisher’s Exact and chi-squared tests respectively. A p-value of <0.05 will be used as threshold of statistical significance.
The primary analysis will include logistic regression to establish the relationship between treatment group and length of stay. Secondary analysis will include logistic regression with multivariate analysis to establish relationship between treatment group and secondary outcome measures.
An attempt will be made to minimise missing data by ensuring adherence to follow up. Multiple contact details will be taken for participants at recruitment to ensure ability to contact in cases of failure to attend appointments. If greater than 10% of data is missing, data will be imputed.

Recruitment
Recruitment status
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)
QLD
Recruitment hospital [1] 6830 0
Princess Alexandra Hospital - Woolloongabba
Recruitment postcode(s) [1] 14495 0
4102 - Woolloongabba

Funding & Sponsors
Funding source category [1] 294727 0
Hospital
Name [1] 294727 0
Princess Alexandra Hospital
Address [1] 294727 0
Princess Alexandra Hospital
199 Ipswich Rd
Woolloongabba 4102
Country [1] 294727 0
Australia
Primary sponsor type
Hospital
Name
Princess Alexandra Hospital
Address
199 Ipswich Rd Woolloongabba
Queensland 4102
Country
Australia
Secondary sponsor category [1] 293570 0
None
Name [1] 293570 0
None
Address [1] 293570 0
None
Country [1] 293570 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 296145 0
Metro South HREC
Ethics committee address [1] 296145 0
199 Ipswich Rd
Woolloongabba
Queensland 4102
Ethics committee country [1] 296145 0
Australia
Date submitted for ethics approval [1] 296145 0
13/10/2016
Approval date [1] 296145 0
03/10/2017
Ethics approval number [1] 296145 0

Summary
Brief summary
To compare patient outcomes between patients admitted for total hip replacement surgery via a posterior approach compared to total hip replacement surgery via an anterior approach. The study hypothesis is that an anterior approach to total hip replacement may lead to a reduced stay in hospital compared to the traditionalposterior approach to hip replacement
Trial website
N/A
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 69730 0
Dr Cameron Cooke
Address 69730 0
Princess Alexandra Hospital
199 Ipswich Rd
Woolloongabba
Queensland 4102
Country 69730 0
Australia
Phone 69730 0
+61 7 31762111
Fax 69730 0
+61 7 31765156
Email 69730 0
cameron.cooke@health.qld.gov.au
Contact person for public queries
Name 69731 0
Dr Paul Tuckett
Address 69731 0
Princess Alexandra Hospital
199 Ipswich Rd
Woolloongabba 4102
Queensland
Country 69731 0
Australia
Phone 69731 0
+61 7 31762111
Fax 69731 0
+61 7 31765156
Email 69731 0
paul.tuckett@health.qld.gov.au
Contact person for scientific queries
Name 69732 0
Dr Paul Tuckett
Address 69732 0
Princess Alexandra Hospital
199 Ipswich Rd
Woolloongabba 4102
Queensland
Country 69732 0
Australia
Phone 69732 0
+61 7 31762111
Fax 69732 0
+61 7 31765156
Email 69732 0
paul.tuckett@health.qld.gov.au

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