Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12609001019291
Ethics application status
Approved
Date submitted
22/11/2009
Date registered
24/11/2009
Date last updated
10/10/2017
Type of registration
Retrospectively registered

Titles & IDs
Public title
Prospective randomised clinical trial assessing the subsidence and rotation of two modular cementless femoral stems
Scientific title
Prospective randomised clinical trial assessing the subsidence and rotation of the K2 and Apex modular cementless femoral stems following primary total hip replacement
Secondary ID [1] 293105 0
nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
End-stage Hip Osteoarthritis 252253 0
Condition category
Condition code
Surgery 252441 252441 0 0
Other surgery
Musculoskeletal 252442 252442 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This study will compare post-operative radiological and clinical outcomes in patients who undergo primary total hip replacement surgery, using two different modular cementless femoral stems (K2 and Apex stems).

K2 (Global Orthopaedic Technology, Sydney Australia) modular hip system’s geometry comprises a dual longitudinal taper with rectangular cross-section. The rationale is to provide axial stability through the dual longitudinal taper and rotational stability through compaction of cancellous bone and the contact between the femoral cortex and the corners of the stem. Apex (Global Orthopaedic Technology, Sydney Australia) modular hip system’s geometry comprises a modular titanium construction with circumferential proximal porous coating of the “fit and fill” body section.

A standard posterior surgical approach will be employed for both stems, while surgical duration should not differ.
Intervention code [1] 241585 0
Treatment: Surgery
Comparator / control treatment
This study will compare outcomes following primary total hip replacement surgery, in combination with two modular cementless femoral stems. Both stems (K2 and Apex) are used routinely in hip replacement surgery.
Control group
Active

Outcomes
Primary outcome [1] 253313 0
Roentgen Stereophotogrammetric Analysis (RSA) is the primary outcome measure, and is the gold standard for assessing the stability of implants within bone. Small tantalum beads will be implanted into the patient's bone to measure micromotion (< 1 mm) at the bone/implant interface. In doing so, we will measure permanent implant migration and instantaneous inducible displacements created by external loading. The pattern of micromotion exhibited by various prostheses and fixation techniques within the first two post-operative years has been shown to be predictive of the long-term fixation of the component to bone.
Timepoint [1] 253313 0
1-week, 3-months, 1-year, 2-years, 5-years and 10-years post-surgery.
Primary outcome [2] 253314 0
Dual X-ray Absorptiometry (DEXA) will be used to calculate bone mineral content (BMC) and density (BMD) in the peri-prosthetic bone of the total joint arthroplasties. The combination of BMD information with RSA derived implant micromotion will enable a comprehensive assessment of the processes which determine implant fixation and long-term survival.
Timepoint [2] 253314 0
Pre-surgery and 1-year, 2-years, 5-years and 10-years post-surgery.
Secondary outcome [1] 262383 0
Harris Hip Score (HHS): The Harris hip score is a disease-specific test used to provide an evaluation system for various hip disabilities and methods of treatment. The HHS gives a maximum of 100 points and the domains include pain, function, deformity and motion.
Timepoint [1] 262383 0
Pre-surgery and 6-weeks, 3-months, 1-year, 2-years, 5-years and 10-years post-surgery.
Secondary outcome [2] 262384 0
Short-Form Health Survey (SF-12): The multi-purpose 12 item questionnaire looks at physical and mental scores for patients undergoing clinical trials.
Timepoint [2] 262384 0
Pre-surgery and 6-weeks, 3-months, 1-year, 2-years, 5-years and 10-years post-surgery.
Secondary outcome [3] 262385 0
Oxford Hip Score (OHS): The Oxford hip score is a disease-specific assessment that evaluates hip pain, symptoms and related function.
Timepoint [3] 262385 0
Pre-surgery and 6-weeks, 3-months, 1-year, 2-years, 5-years and 10-years post-surgery.

Eligibility
Key inclusion criteria
Inclusion Criteria
1.The individual has signed a Patient Informed Consent, specific to this study, and approved by the Institutional Ethics Review Board.
2.The individual is between the ages of 21 and 75 years.
3.The individual clinically qualifies for total hip arthroplasty (THA) surgery based on physical examination and history.
4.The individual is diagnosed with a primary diagnosis of Non Inflammatory Degenerative Joint Disease (osteoarthritis, traumatic arthritis, avascular necrosis, slipped capital epiphysis, pelvic fracture, femoral fracture, failed fracture fixation or diastrophic variant).
5.The individual is physically and mentally willing and able to comply with postoperative scheduled clinical and radiographic evaluations and rehabilitation (i.e., not currently being treated for a psychiatric disorder, senile dementia, Alzheimer’s disease, presence of alcohol/substance abuse).
6.The individual is skeletally mature.
Minimum age
21 Years
Maximum age
75 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Exclusion Criteria
1.The individual is classified as morbidly obese (>40 Body Mass Index).
2.The individual has an active infection within the affected hip joint.
3.The individual has a diagnosed systemic disease that would affect the subject’s welfare or overall outcome of the study (i.e., moderate to severe osteoporosis, Paget's disease, renal osteodystrophy), is immunologically suppressed, or receiving steroids in excess of physiologic dose requirements.
4.The individual is pregnant.
5.The individual is a prisoner.
6.The individual has plans to relocate to another geographic area before study completion.

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)
Once patients have been assessed by the orthopaedic surgeon for the associated inclusion/exclusion criteria, are well informed about the study and provide their written, informed consent, randomisation will be undertaken. Allocation is concealed, and involves contacting the holder of the allocation schedule who is located at an independent office “off-site”.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A ‘random number generator’ using Microsoft Excel will create a random list numbers (1=K2 stem; 2=Apex stem).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Stopped early
Data analysis
Data analysis is complete
Reason for early stopping/withdrawal
Participant recruitment difficulties
Date of first participant enrolment
Anticipated
1/08/2009
Actual
21/09/2009
Date of last participant enrolment
Anticipated
Actual
18/11/2011
Date of last data collection
Anticipated
Actual
29/11/2013
Sample size
Target
260
Accrual to date
Final
95
Recruitment in Australia
Recruitment state(s)
WA

Funding & Sponsors
Funding source category [1] 244064 0
Commercial sector/Industry
Name [1] 244064 0
Global Orthopaedic Technology
Country [1] 244064 0
Australia
Funding source category [2] 244065 0
Hospital
Name [2] 244065 0
Hollywood Private Hospital
Country [2] 244065 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
Global Orthopaedic Technology
Address
PO Box 7745, Baulkham Hills BC NSW 2153
Country
Australia
Secondary sponsor category [1] 251410 0
None
Name [1] 251410 0
Address [1] 251410 0
Country [1] 251410 0
Other collaborator category [1] 968 0
University
Name [1] 968 0
University of Western Australia
Address [1] 968 0
Stirling Highway, Crawley, WA, 6009
Country [1] 968 0
Australia
Other collaborator category [2] 969 0
Hospital
Name [2] 969 0
Sir Charles Gairdner Hospital
Address [2] 969 0
Hospital Avenue, Nedlands, WA, 6009
Country [2] 969 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 258164 0
Hollywood Private Hospital Ethics Committee
Ethics committee address [1] 258164 0
Monash Avenue, Nedlands, WA, 6009
Ethics committee country [1] 258164 0
Australia
Date submitted for ethics approval [1] 258164 0
Approval date [1] 258164 0
18/06/2009
Ethics approval number [1] 258164 0
HPH277

Summary
Brief summary
This research project sought to assess the migration patterns and rotational stability of two modular cementless femoral stems (K2 and Apex, Global Orthopaedic technology) used routinely for hip replacement surgery.
Trial website
Trial related presentations / publications
Publications
1. Edmondson M, Ebert J, Nivbrant O, Wood D. Prospective randomised clinical trial assessing subsidence and rotation, using radiostereometric analysis, of two modular cementless femoral stems (Global K2 and Apex). J Orthop. 2014;11(2):96-102.
2. Kent M, Edmondson M, Ebert J, et al. Stem Migration and Fretting Corrosion of the Antirotation Pin in the K2/Apex Hip System. J Arthroplasty. 2015.
Public notes

Contacts
Principal investigator
Name 30537 0
Prof David Wood
Address 30537 0
Perth Orthopaedic Institute
Country 30537 0
Australia
Phone 30537 0
+61 08 93869961
Fax 30537 0
Email 30537 0
[email protected]
Contact person for public queries
Name 13784 0
Dr Dr Jay Ebert
Address 13784 0
Perth Orthopaedic Institute
Gate 3, Verdun Street,
Nedlands, WA, 6009
Country 13784 0
Australia
Phone 13784 0
+61 8 9386 9961
Fax 13784 0
+61 8 9346 6462
Email 13784 0
[email protected]
Contact person for scientific queries
Name 4712 0
Dr Dr Jay Ebert
Address 4712 0
Perth Orthopaedic Institute
Gate 3, Verdun Street,
Nedlands, WA, 6009
Country 4712 0
Australia
Phone 4712 0
+61 8 9386 9961
Fax 4712 0
+61 8 9346 6462
Email 4712 0
[email protected]

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

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