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Trial registered on ANZCTR


Registration number
ACTRN12616000604404
Ethics application status
Approved
Date submitted
27/04/2016
Date registered
10/05/2016
Date last updated
13/04/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
KBARS Study: The effect of knee prosthesis design on knee biomechanics during locomotion following knee replacement surgery
Scientific title
KBARS Study: The effect of knee prosthesis design on knee biomechanics during locomotion following knee replacement surgery
Secondary ID [1] 289085 0
Nil
Secondary ID [2] 289150 0
Nil
Universal Trial Number (UTN)
U1111-1182-3836
Trial acronym
KBARS
Linked study record

Health condition
Health condition(s) or problem(s) studied:
knee osteoarthritis 298540 0
Condition category
Condition code
Musculoskeletal 298624 298624 0 0
Osteoarthritis
Surgery 298732 298732 0 0
Other surgery

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
1. Patients implanted with a medial pivot prosthesis design, an cruciate sacrificing design characterised by high-conformity in the medial compartment (socket on the insert, as well as anterior and posterior lips to prevent femoral translation) and a flatter tibial surface on the lateral side to facilitate tibiofemoral rotation with an axis located on the medial side. Alternative designs such as cruciate-retaining (CR) do not feature medial-lateral differences in geometry and retain the posterior-cruciate ligament. Posterior stabilized knees (PS) also sacrifice the cruciate ligaments, but maintain stability through a post and cam system.

2. Each participant will be followed up for a one-hour session at a minimum follow-up of 12months post knee replacement surgery.
Intervention code [1] 294593 0
Not applicable
Comparator / control treatment
1. Patients implanted with a cruciate-retaining (control group 1) or posterior-stabilizing (control group 2) prosthesis design. A cruciate-retaining design retains the posterior cruciate ligament, while the posterior-stabilized design sacrifices both cruciate ligaments and maintains stability with a post and cam arrangement.
2. Each participant will be followed up for a one-hour session at a minimum follow-up of 12months post knee replacement surgery.
Control group
Active

Outcomes
Primary outcome [1] 298120 0
tibial rotation during locomotion (walking and stepping) measured by optoelectronic motion capture (9-camera Vicon) in a laboratory environment
Timepoint [1] 298120 0
during a single session at least 12months after knee replacement
Secondary outcome [1] 323222 0
Muscle activity amplitude, assessed by electromyography
Timepoint [1] 323222 0
during a single session at least 12months after knee replacement
Secondary outcome [2] 323223 0
knee pain and function, assessed using the Oxford Knee Score
Timepoint [2] 323223 0
during a single session at least 12months after knee replacement

Eligibility
Key inclusion criteria
Patients receiving a knee replacement a minimum of 12months prior to testing
BMI <35kg/m2
Able to walk on a treadmill for >120sec; step up/down on a 20cm step
Minimum age
45 Years
Maximum age
90 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Primary language other than English
Pregnant women
Children or young adults
Persons diagnosed with neurological disorders that would preclude safely performing locomotion in a laboratory environment
Persons with intellectual or mental impairments
People highly dependent on medical care

Study design
Purpose
Natural history
Duration
Cross-sectional
Selection
Case control
Timing
Prospective
Statistical methods / analysis
A power analysis conducted with GPower (v3.1.9) (Faul, Erdfelder, Buchner, & Lang, 2009) suggests that a total sample size of 66 (22 in each group; CR; PS; Evolution) is required to detect a “large” difference in tibial rotation between prosthesis types using a one-way analysis of variance (ANOVA) with power of 80% and alpha set at 5%. To account for any technical issues with data collection an additional 2 patients per group (10%) will be recruited for a total sample of 72.

Aim 1
The first aim of the study will be addressed by the use of two alternative techniques. The first assumes that each patient has been appropriately matched for age, gender, BMI and surgery to followup delay across each of the implant design groups. Therefore, each of the 25 patients recruited into the medial-pivot group will be compared to a matched control in the PS and CR groups. A one-way ANOVA will be performed comparing tibiofemoral rotation and muscle activation amplitude on each trio of patients (N = 25) and the proportion of significant differences calculated for each dependent variable. The alternative will be to aggregate the data within each group and compare the three groups with a one-way ANOVA. In both techniques, significant confounders identified will be included as a covariate.
Aim 2
A significant relationship between tibiofemoral motion and muscle activity will be assessed using a form of multivariate multilinear regression with self-reported questionnaires (VR-12, OKS) as dependent variables and the kinematic and electromyography measures as independent variables. The average knee biomechanics data from each partipant will be included in the model (N = 66 – 75) and a partial least squares regression model will be used to examine the relationship between the independent and dependent variables.

Recruitment
Recruitment status
Completed
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] 5748 0
Lake Macquarie Private Hospital - Gateshead
Recruitment hospital [2] 5749 0
North Shore Private Hospital - St Leonards
Recruitment hospital [3] 5750 0
Mater Sydney - North Sydney
Recruitment postcode(s) [1] 13175 0
2067 - Chatswood
Recruitment postcode(s) [2] 13217 0
2065 - Crows Nest
Recruitment postcode(s) [3] 13218 0
2065 - St Leonards
Recruitment postcode(s) [4] 13219 0
2290 - Gateshead

Funding & Sponsors
Funding source category [1] 293462 0
Charities/Societies/Foundations
Name [1] 293462 0
Sydney Orthopaedic Research Institute
Address [1] 293462 0
Level 1, 445 Victoria Avenue, Chatswood, NSW, 2067
Country [1] 293462 0
Australia
Funding source category [2] 293464 0
Commercial sector/Industry
Name [2] 293464 0
Therapy Specialties
Address [2] 293464 0
3/17 Rodborough Rd,
Frenchs Forest, NSW, 2086, Australia
Country [2] 293464 0
Australia
Primary sponsor type
Charities/Societies/Foundations
Name
Sydney Orthopaedic Research Institute
Address
Level 1, 445 Victoria Avenue, Chatswood, NSW, 2067
Country
Australia
Secondary sponsor category [1] 292285 0
None
Name [1] 292285 0
Address [1] 292285 0
Country [1] 292285 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 294905 0
Northern Sydney Local Health District
Ethics committee address [1] 294905 0
Kolling Building, Level 13, Royal North Shore Hospital, St Leonards, NSW, 2065
Ethics committee country [1] 294905 0
Australia
Date submitted for ethics approval [1] 294905 0
09/11/2015
Approval date [1] 294905 0
18/02/2016
Ethics approval number [1] 294905 0
HREC/15/HAWKE/429

Summary
Brief summary
The purpose of this study is to determine if knee movement and muscle activity of patients implanted with a medial pivot prosthesis design is more normal compared to crucial-retaining or posterior-stabilized designs during locomotion.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 65410 0
A/Prof David Parker
Address 65410 0
Sydney Orthopaedic Research Institute
Level 1, 445 Victoria Avenue, Chatswood, NSW, 2067
Country 65410 0
Australia
Phone 65410 0
+61 2 9904 7182
Fax 65410 0
Email 65410 0
dparker@sydneyortho.com.au
Contact person for public queries
Name 65411 0
Dr Aaron Beach
Address 65411 0
Sydney Orthopaedic Research Institute
Level 1, 445 Victoria Avenue, Chatswood, NSW, 2067
Country 65411 0
Australia
Phone 65411 0
+61 2 9904 7182
Fax 65411 0
Email 65411 0
abeach@sori.com.au
Contact person for scientific queries
Name 65412 0
Dr Aaron Beach
Address 65412 0
Sydney Orthopaedic Research Institute
Level 1, 445 Victoria Avenue, Chatswood, NSW, 2067
Country 65412 0
Australia
Phone 65412 0
+61 2 9904 7182
Fax 65412 0
Email 65412 0
abeach@sori.com.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary