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Trial registered on ANZCTR


Registration number
ACTRN12615000796583
Ethics application status
Approved
Date submitted
13/07/2015
Date registered
31/07/2015
Date last updated
31/07/2015
Type of registration
Prospectively registered

Titles & IDs
Public title
Evaluation of anatomical head center, gait and bone re-modelling after Total hip replacement – Randomized controlled trial of neck preserving versus conventional hip prosthesis
Scientific title
A Single Centre, Participant-Blinded, Randomized, 12 Month, Parallel Group, Trial Of The Anatomical Head Center, Gait And Bone Remodelling After Total Hip Replacement Using Cementless Neck Preserving Versus Conventional Hip Prosthesis
Secondary ID [1] 287068 0
nil
Universal Trial Number (UTN)
U1111-1172-0486
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis 295566 0
Total Hip Replacement 295670 0
Condition category
Condition code
Musculoskeletal 295834 295834 0 0
Osteoarthritis
Surgery 295947 295947 0 0
Surgical techniques

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The intervention involves the surgical replacement of the hip joint performed by an orthopaedic surgeon using the Minihip Stem (Corin Ltd) hip prosthesis. This stem is designed as a femoral neck preserving, short prosthesis with the philosophy of bone preservation in the proximal area (metaphysis) of the femur.
Surgical approach will be via the direct anterior approach. Approximate duration of the surgical procedure is 60-90 minutes.
Intervention code [1] 292301 0
Treatment: Devices
Intervention code [2] 292427 0
Treatment: Surgery
Comparator / control treatment
The control intervention involves the surgical replacement of the hip joint performed by an orthopaedic surgeon using the Metafix Stem (Corin Ltd) hip prosthesis. This stem is a conventional hip stem prosthesis, that does not preserve the femoral neck. Conventional hip stems are the most commonly utilised femoral prostheses and are standard of care.
Surgical approach will be via the direct anterior approach. Approximate duration of the surgical procedure is 60-90 minutes.
Control group
Active

Outcomes
Primary outcome [1] 295524 0
Anatomical Centre of Rotation defined by Horizontal Femoral Offset (mm), Horizontal Centre of Rotation (mm), Vertical Centre of Rotation (mm), Vertical Femoral Offset (mm), and Anteversion (degrees), leg length will be measured using plain radiographs (A-P and modified Budin views)
Timepoint [1] 295524 0
Pre-Operative and 3 months post operative
Secondary outcome [1] 315774 0
Bone Density (T Score) using DEXA scan of the femur
Timepoint [1] 315774 0
Immediate Post Operative and 1 year
Secondary outcome [2] 315775 0
Gait Analysis; velocity (m/s), cadence (m), step length (m), gait cycle duration (seconds), stance phase duration (seconds), swing phase duration (seconds), double and single support duration (seconds). Data for gait analysis will be acquired using the BTS G-Walk (patient wearable device) and managed through the compatible software, BTS G-Studio Software.
Timepoint [2] 315775 0
Pre Operative, 3 months, 1 year, 2 years and 5 years
Secondary outcome [3] 315776 0
Quality of life assessed through patient-reported health survey; the Short Form (36) Health Survey (SF36)
Timepoint [3] 315776 0
Pre Operative, 3 months, 1 year, 2 years and 5 years
Secondary outcome [4] 316163 0
Quality of life assessed through patient-reported health survey; the Oxford Hip Score (OHS).
Timepoint [4] 316163 0
Pre Operative, 3 months, 1 year, 2 years and 5 years

Eligibility
Key inclusion criteria
1. Eligible for a primary total hip replacement
2. Dorr type A femur
3. Willing to comply with the protocol
4. Willing and competent to consent
Minimum age
30 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. Not meeting the inclusion criteria
2. Any patient with a revision / resurfacing or a hemi hip replacement
3. Patients with a Dorr type B or C femur
4. Cemented hip replacement
5. Medically Unfit for surgery
6. Not willing to comply with the protocol
7. Not willing or competent to 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)
Participants will be randomly assigned to either group with a 1:1 allocation as per a computer generated randomization schedule by using permuted blocks of random sizes. The block sizes will not be disclosed, to ensure concealment. Participants will be randomized using the Interactive Voice response System provided by the NHMRC Clinical Trials Center, which is an online central randomization service. Allocation concealment will be ensured, as the service will not release the randomization code until just before the patient is going to be operated has been recruited into the trial, which takes place after all baseline measurements have been completed. The investigators will obtain this code just before the start of the surgery.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The allocation sequence will be generated by the IVRS by the NHMRC-CTC applying a permuted block design with random blocks stratified by age. The randomization list remains with them for the whole duration of the study. Thus, randomization will be conducted without any influence of the principal investigators.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Baseline patient demographic (age, sex, ethnicity, other) and clinical characteristics (height, weight, BMI, ROM, leg length) will be summarised for each study arm using means and SD, or medians and interquartile ranges for continuous variables and percentages for categorical variables.

Pilot data available for 20 patients has been used to conservatively estimate the difference in horizontal femoral offset (baseline - 3 month) between the groups is 7mm, with a standard deviation of 6. Based on this information, the sample size required for this study has been calculated as 32 patients (16 patients per group) to detect a statistically significant difference in the mean difference in the horizontal femoral offset at 3 months compared to baseline (primary outcome) between the study groups using the independent t-test. Taking into account the possibility of cross-overs from the NPP arm to standard arm and drop outs we have increased the sample size estimation to 20 patients per group.
This sample size will allow us to reject the null hypothesis that this response difference is zero with probability (power) 0.90. The Type I error probability associated with this test of this null hypothesis is 0.05.

Recruitment
Recruitment status
Not yet 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
Recruitment hospital [1] 4029 0
Norwest Private Hospital - Bella Vista
Recruitment hospital [2] 4030 0
Macquarie University Hospital - Macquarie Park
Recruitment hospital [3] 4031 0
Sydney Adventist Hospital - Wahroonga

Funding & Sponsors
Funding source category [1] 291627 0
Commercial sector/Industry
Name [1] 291627 0
CORIN (Australia) Pty Ltd
Address [1] 291627 0
17 Bridge St
Pymble NSW 2073
Country [1] 291627 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
CORIN (Australia) Pty Ltd
Address
17 Bridge St
Pymble NSW 2073
Country
Australia
Secondary sponsor category [1] 290299 0
None
Name [1] 290299 0
Address [1] 290299 0
Country [1] 290299 0
Other collaborator category [1] 278519 0
Individual
Name [1] 278519 0
Aditya Khemka
Address [1] 278519 0
Norwest Advanced Orthopedics
Suite G 3 B, Norwest Private Hospital,
9 Norbik Drive, Bella Vista, NSW – 2153
Australia
Country [1] 278519 0
Australia
Other collaborator category [2] 278520 0
Individual
Name [2] 278520 0
Munjed Al Muderis
Address [2] 278520 0
Norwest Advanced Orthopedics
Suite G 3 B, Norwest Private Hospital,
9 Norbik Drive, Bella Vista, NSW – 2153
Australia
Country [2] 278520 0
Australia
Other collaborator category [3] 278521 0
Individual
Name [3] 278521 0
Sally Lord
Address [3] 278521 0
School of Medicine,
Sydney,
University of Notre Dame Australia
160 Oxford Street,
Darlinghurst, NSW, 2010
Country [3] 278521 0
Australia
Other collaborator category [4] 278523 0
Individual
Name [4] 278523 0
Zelda Doyle
Address [4] 278523 0
School of Medicine,
Sydney,
University of Notre Dame Australia
160 Oxford Street,
Darlinghurst, NSW, 2010
Country [4] 278523 0
Australia
Other collaborator category [5] 278524 0
Individual
Name [5] 278524 0
Belinda Bosley
Address [5] 278524 0
Norwest Advanced Orthopedics
Suite G 3 B, Norwest Private Hospital,
9 Norbik Drive, Bella Vista, NSW – 2153
Australia
Country [5] 278524 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293158 0
The University of Notre Dame
Ethics committee address [1] 293158 0
19 Mouat street
Fremantle WA 6959
Ethics committee country [1] 293158 0
Australia
Date submitted for ethics approval [1] 293158 0
01/05/2015
Approval date [1] 293158 0
09/07/2015
Ethics approval number [1] 293158 0
014160S

Summary
Brief summary
This clinical study is a single centre, prospective, randomized, participant-blinded trial enrolling 40 patients to receive either a Cementless Neck Preserving stem or a Conventional Hip stem Prosthesis.
Neck preserving prostheses to offer a more physiological load transmission across the femur, the nature of achieving a stable press-fit means that the stem must adapt to the geometry of the bone. As patient anatomy is highly variable, there is limited ability to adjust the femoral offset, centre of rotation, femoral anteversion and leg length. It is unclear whether anatomical restoration, offered by neck preserving prostheses is comparable to conventional prostheses. The success of the neck preserving systems relies on the precise positioning and sizing of the implant and the excellent long-term durability of the ceramic bearings.
Hence, we propose a randomized comparative study to assess and compare the anatomical head centre, gait analysis and bone remodelling of two parallel groups receiving either a Neck preserving or a Conventional hip stem prosthesis by the direct anterior approach.
Antero-posterior and modified Budin x-rays will be analysed at preoperatively, 3 months, 12 months, 2 years and 5 years to assess femoral head offset, stem orientation and leg length.
DEXA (bone density) scans will be assessed pre-operatively and 12 months to measure femoral bone density, with the aim of assessing bone remodelling after total hip replacement.
Spatial-Temporal gait analysis will be used to quantify measurement of standard gait (6 minute walking test – 6MWT) and sit-to-stand preoperatively, 3 months and 12 months.
Standard, functional parameters will be assessed pre-operatively, 3 months, 12 months, 2 years and 5 years.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 58702 0
Dr Munjed Al Muderis
Address 58702 0
Norwest Advanced Orthopedics
Suite G 3 B, Norwest Private Hospital,
9 Norbik Drive, Bella Vista, NSW – 2153
Australia
Country 58702 0
Australia
Phone 58702 0
1800-907-905
Fax 58702 0
Email 58702 0
munjed@me.com
Contact person for public queries
Name 58703 0
Ms Belinda Bosley
Address 58703 0
Norwest Advanced Orthopedics
Suite G 3 B, Norwest Private Hospital,
9 Norbik Drive, Bella Vista, NSW – 2153
Australia
Country 58703 0
Australia
Phone 58703 0
1800-907-905
Fax 58703 0
Email 58703 0
belindabosley@gmail.com
Contact person for scientific queries
Name 58704 0
Dr Aditya Khemka
Address 58704 0
Norwest Advanced Orthopedics
Suite G 3 B, Norwest Private Hospital,
9 Norbik Drive, Bella Vista, NSW – 2153
Australia
Country 58704 0
Australia
Phone 58704 0
1800-907-905
Fax 58704 0
Email 58704 0
adk_sun@hotmail.com

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