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Trial registered on ANZCTR


Registration number
ACTRN12618000107224
Ethics application status
Approved
Date submitted
11/12/2017
Date registered
24/01/2018
Date last updated
24/01/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
Fixation of polyethylene knee replacement tibial components in patients with osteoarthritis aged 18-60
Scientific title
Migration characteristics of the Profix all-polyethylene tibial component in patients with osteoarthritis aged 18-60
Secondary ID [1] 293587 0
none
Universal Trial Number (UTN)
U1111-1206-5052
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
knee osteoarthritis 305831 0
Condition category
Condition code
Musculoskeletal 305045 305045 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Routine total knee replacement using a Profix (Smith & Nephew, USA) implant. All-polyethylene implant used in all patients.

Standard surgical procedure of 60-90 minutes duration.
Intervention code [1] 299840 0
Treatment: Surgery
Comparator / control treatment
Historical control.Norgren, B., Dalen, T., and Nilsson, K. G.: All-poly tibial component better than metal-backed: a randomized RSA study. Knee. 11:189-196, 2004. Authors previous study used same implant and study design in patients aged greater than 60 years. Previous study randomised 21 patients to receive an all-polyethylene tibial component or a modular metal-backed component. Surgery performed in Umea 1999-2000
Control group
Historical

Outcomes
Primary outcome [1] 304206 0
Migration of tibial component measured with radiostereometric analysis (RSA)
Timepoint [1] 304206 0
Immediate post op, 12 months, 24 months, and 10 years
Secondary outcome [1] 341252 0
Excessive tibial migration:
Components classified as stable or unstable by a composite categorical endpoint determined by;
1. tibial components were classified into being non-migrating (stable) or continuously migrating (unstable) migration greater than 200um by RSA.
2. presence and size of radiolucent lines at the tibial component interface as described by the Knee Society assessment of plain films.
Timepoint [1] 341252 0
immediate post operative, 1, 2 and 10 years

Eligibility
Key inclusion criteria
osteoarthritic patients booked to have knee replacement surgery
Minimum age
18 Years
Maximum age
60 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
previous surgery
weight > 120kg
inflammatory arthritis
severe anatomical abnormalities
non-metropolitan residence

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
none
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
comparison to authors historical series of older patients
Phase
Phase 4
Type of endpoint(s)
Safety/efficacy
Statistical methods / analysis
descriptive measures of migration
secondary analysis with comparison of means to historical controls

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)
SA
Recruitment hospital [1] 9529 0
Calvary Wakefield Hospital - Adelaide
Recruitment postcode(s) [1] 18279 0
5000 - Adelaide

Funding & Sponsors
Funding source category [1] 298204 0
Self funded/Unfunded
Name [1] 298204 0
Address [1] 298204 0
Country [1] 298204 0
Primary sponsor type
Individual
Name
David Campbell
Address
Wakefield Orthopaedic Clinic
270 Wakefield Street
Adelaide
5000
Country
Australia
Secondary sponsor category [1] 297303 0
None
Name [1] 297303 0
Address [1] 297303 0
Country [1] 297303 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 299212 0
Wakefield Hospital Ethics Committee
Ethics committee address [1] 299212 0
250 Wakefield street
Adelaide
South Australia 5000
Ethics committee country [1] 299212 0
Australia
Date submitted for ethics approval [1] 299212 0
03/08/2005
Approval date [1] 299212 0
14/11/2005
Ethics approval number [1] 299212 0
05 CHREC-1411

Summary
Brief summary
All-polyethylene (AP) tibial components in patients aged greater than 60 years have stable tibial migration patterns and favorable survival rates when compared to identical metal-backed (MB) designs. Tibial component fixation in patients aged less than 60 years was measured with radiostereometric analysis (RSA) and compared to a previous cohort of AP and MB tibial components of identical design in patients aged greater than 60 years.
Methods
A prospective consecutive study examined tibial component migration in 21 patients aged less than 60 years undergoing a cemented total knee arthroplasty with an AP tibial component by RSA to 24 months. Results were compared to the authors previous series of 21 patients aged greater than 60 years that were randomized to either an AP or MB tibial component. The articulating geometry and stem design of the implants were identical as were the operative technique and post-operative regime
Results
At 2-years both age groups of patients implanted with an all-polyethylene component had stable migration patterns with no patient having greater than 0.2 degree rotation or 0.5mm maximum total point motion. Five of 11 metal-backed tibial components displayed continued migration between 1 and 2 years. Median internal/external rotation was greater with MB components; 0.15, 0.08, 0.28, AP < 60 years, AP > 60 years, and MB cohorts. Subsidence significantly greater for MB implants; median subsidence 0.17, 0.10, 0.25, AP < 60 years, AP > 60 years, and MB cohorts. Median maximum total point motion was greater for the MB cohort 0.34, 0.33, 0.61mm, AP < 60 years, AP > 60 years, and MB cohorts
Conclusions
Young patients implanted with an all-polyethylene tibial component had stable tibial migration patterns comparable to older patients with the same all-polyethylene implant. Regardless of age, all-polyethylene tibial components were at least as stable as metal-backed tibial components. The study will continue until 10-years.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 79674 0
A/Prof David Campbell
Address 79674 0
Wakefield Orthopaedic Clinic
270 Wakefield Street
Adelaide
South Australia, 5000
Country 79674 0
Australia
Phone 79674 0
+61 8 8236 4196
Fax 79674 0
+61 8 8236 4180
Email 79674 0
hipknee@tpg.com.au
Contact person for public queries
Name 79675 0
Mrs Chris Schultz
Address 79675 0
Wakefield Orthopaedic Clinic
270 Wakefield Street
Adelaide
South Australia 5000
Country 79675 0
Australia
Phone 79675 0
+61 8 8236 4196
Fax 79675 0
+61 8 8236 4180
Email 79675 0
cschutz@woc.com.au
Contact person for scientific queries
Name 79676 0
A/Prof David Campbell
Address 79676 0
Wakefield Orthopaedic Clinic
270 Wakefield Street
Adelaide
South Australia 000
Country 79676 0
Australia
Phone 79676 0
+61 8 8236 4196
Fax 79676 0
+61 8 8236 4180
Email 79676 0
hipknee@tpg.com.au

No data has been provided for results reporting
Summary results
Have study results been published in a peer-reviewed journal?
Yes
Journal publication details
Publication date and citation/details [1] 897 0
early 2019
The Knee
citation details tab
Attachments [1] 897 0
Other publications
Have study results been made publicly available in another format?
No
Results – basic reporting
Results – plain English summary
All-Polyethylene Tibial Components In Young Patients Have Stable Fixation; A comparison RSA Study
Abstract
All-polyethylene (AP) tibial components in patients aged greater than 60 years have stable tibial migration patterns and favorable survival rates when compared to identical Metal-backed (MB) designs. Tibial component migration in younger patients has not been reported. The aim of this study was to examine the migration characteristics of patients aged less than 60 years compared to a previous cohort of AP and MB tibial components of identical design in older patients.
Methods
A prospective consecutive study examined tibial component migration in 21 patients aged less than 60 years undergoing a cemented total knee arthroplasty with an AP tibial component by radiostereometric analysis (RSA) to 24 months. Results were compared to the authors previous series of 21 patients aged greater than 60 years that were randomized to either an AP or MB tibial component. The articulating geometry and stem design of the implants were identical as were the operative technique and post-operative regime.
Results
Both age groups of patients implanted with an AP component had stable migration patterns with no patient having greater than 0.2 degree rotation or 0.2mm maximum total point motion. Five of 11 MB tibial components displayed continued migration between 1 and 2 years. Subsidence was similar in all groups, maximum total point motion was greater for the MB cohort (0.34mm, 0.33mm, 0.61mm; AP<60, AP>60, MB) .
Conclusions
Young patients implanted with an AP tibial component had stable tibial migration patterns comparable to older patients with the same AP implant. Regardless of age, AP tibial components were at least as stable as MB tibial components.