Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625000956404
Ethics application status
Approved
Date submitted
21/04/2025
Date registered
1/09/2025
Date last updated
1/09/2025
Date data sharing statement initially provided
1/09/2025
Type of registration
Retrospectively registered

Titles & IDs
Public title
Trial comparing fixed versus mobile bearing medial unicompartmental knee replacements
Scientific title
Fixed versus mobile bearing medial unicompartmental knee replacements: A randomised trial looking at clinical outcomes and complications with a minimum of 10-year follow-up
Secondary ID [1] 314141 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Knee arthrosis 336956 0
Condition category
Condition code
Musculoskeletal 333428 333428 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The long-term results of fixed versus mobile bearing medial unicompartmental knee replacements will be compared. The intervention will be delivered by fellowship trained knee surgeons and the minimum number of patients required for that study will be determined by the sample size calculation performed based on the Oxford score. The procedures will be performed at the Southmead Hospital. The fixed bearing medial unicompartmental knee replacement differs from the mobile bearing replacement due to the fact that there is no mobile bearing component. The anticipated duration of surgery is 1-1.5 hours.
Intervention code [1] 330728 0
Treatment: Surgery
Comparator / control treatment
Mobile bearing medial unicompartmental knee replacements will be considered as control group in this study. Mobile bearing medial unicompartmental knee replacement allow the insert to rotate and translate slightly in relation to both the femoral component and the tibial tray during knee flexion and extension. The intervention will be delivered by fellowship trained knee surgeons and the minimum number of patients required for that study will be determined by the sample size calculation performed based on the Oxford score. The procedures will be performed at the Southmead Hospital.
Control group
Active

Outcomes
Primary outcome [1] 340997 0
Knee pain and function.
Timepoint [1] 340997 0
The primary outcomes will be assessed at 2, 5, 8, 10 (primary timepoint), 12 and 15 years post-operatively.
Primary outcome [2] 342038 0
Knee pain and function.
Timepoint [2] 342038 0
The primary outcomes will be assessed at 2, 5, 8, 10 (primary timepoint), 12 and 15 years post-operatively.
Primary outcome [3] 342039 0
Knee pain and function.
Timepoint [3] 342039 0
The primary outcomes will be assessed at 2, 5, 8, 10 (primary timepoint), 12 and 15 years post-operatively.
Secondary outcome [1] 445739 0
Secondary outcomes will include the assessment of complications (eg reoperations and component revisions).
Timepoint [1] 445739 0
The secondary outcomes will be assessed at 2, 5, 8, 10, 12 and 15 years post-operatively.
Secondary outcome [2] 451682 0
Evaluation of complications
Timepoint [2] 451682 0
The secondary outcomes will be assessed at 2, 5, 8, 10, 12 and 15 years post-operatively.

Eligibility
Key inclusion criteria
Inclusion criteria were male or female patients under 70 years of age undergoing medial unicompartmental knee replacement. Also, patients’ ability to provide consent form and cooperate throughout the study were necessary.
Minimum age
18 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion criteria were inflammatory arthritis, significant anterior or lateral knee pain, ACL deficiency, fixed flexion deformity more than 15 degrees, fixed varus deformity, lateral tibial subluxation, flexion range less than 90 degrees, arthritis of the patellofemoral or lateral femorotibial joint of Grade 2 or more. Also, patients with neuropathic arthropathy and / or active sepsis were ruled out. What is more patients with earlier ipsilateral knee surgery other than arthroscopy, meniscectomy or chondroplasty were not considered.

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)
Sealed envelopes containing the randomized group will be opened intraoperatively. The patients will be informed of which group they were in after the operation. Written consent will be obtained from all patients.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
The sample size will be calculated based upon the primary outcome of this study (ie Oxford score), with a p value of 0.5 and power set to 90%. The student’s t-test will be used to compare the results between the fixed and mobile bearing groups, with the p value being 0.05. Survivorship will be analysed by means of Kaplan-Meier’s method.

Recruitment
Recruitment status
Active, not recruiting
Date of first participant enrolment
Anticipated
Actual
21/07/2006
Date of last participant enrolment
Anticipated
Actual
29/10/2014
Date of last data collection
Anticipated
30/04/2030
Actual
Sample size
Target
208
Accrual to date
Final
163
Recruitment outside Australia
Country [1] 26949 0
United Kingdom
State/province [1] 26949 0
Bristol

Funding & Sponsors
Funding source category [1] 318651 0
Commercial sector/Industry
Name [1] 318651 0
Corin LTD
Country [1] 318651 0
United Kingdom
Primary sponsor type
Commercial sector/Industry
Name
Corin LTD
Address
Country
United Kingdom
Secondary sponsor category [1] 321071 0
None
Name [1] 321071 0
Address [1] 321071 0
Country [1] 321071 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 317262 0
Frenchay Research Ethics Committee
Ethics committee address [1] 317262 0
Ethics committee country [1] 317262 0
United Kingdom
Date submitted for ethics approval [1] 317262 0
01/06/2006
Approval date [1] 317262 0
02/06/2006
Ethics approval number [1] 317262 0
06/Q2007/21

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 140498 0
Mr Kostas Tsikopoulos
Address 140498 0
NBT North Bristol NHS Trust, Southmead Rd, Bristol BS10 5NB
Country 140498 0
United Kingdom
Phone 140498 0
+441174148131
Fax 140498 0
Email 140498 0
[email protected]
Contact person for public queries
Name 140499 0
Rachel Bray
Address 140499 0
NBT North Bristol NHS Trust, Southmead Rd, Bristol BS10 5NB
Country 140499 0
United Kingdom
Phone 140499 0
+441174148131
Fax 140499 0
Email 140499 0
[email protected]
Contact person for scientific queries
Name 140500 0
Kostas Tsikopoulos
Address 140500 0
NBT North Bristol NHS Trust, Southmead Rd, Bristol BS10 5NB
Country 140500 0
United Kingdom
Phone 140500 0
+441174148131
Fax 140500 0
Email 140500 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


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.