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Trial registered on ANZCTR


Registration number
ACTRN12616001705471
Ethics application status
Approved
Date submitted
28/11/2016
Date registered
13/12/2016
Date last updated
15/02/2021
Date data sharing statement initially provided
22/03/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Does the use of the Verasense pressure sensor device and alignment method produce a more balanced knee in patients undergoing total knee arthroplasty
Scientific title
Influence of prosthesis alignment: Does kinematic alignment result in a more balanced total knee arthroplasty when utilising the Verasense pressure sensor device?
Secondary ID [1] 290613 0
Nil Known
Universal Trial Number (UTN)
Trial acronym
Verasense KvM
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis 301109 0
Condition category
Condition code
Musculoskeletal 300880 300880 0 0
Osteoarthritis
Surgery 300881 300881 0 0
Surgical techniques

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The procedure being studied is total knee arthroplasty and the method of aligning the total knee arthroplasty tibial (shin bone) and femoral (thigh bone) prostheses. The two alignment methods typically cause changes to the soft tissue envelope around the knee causing changes to loading forces and pressures across the knee. We will using a pressure sensing device called Verasense that is placed between the tibial and femoral prostheses. The procedure itself will take approximately 1.5 hours to complete.

The two arms of the study are the two alignment methods. Arm 1 is a Kinematic Alignment method and Arm 2 is a Mechanical Alignment method. Mechanical alignment is the most widely used and classical method of alignment and thus it will act as the control.

Study Procedures
1) Preoperative Assessment
Once the participant have been consented into the study, they will have their pre-operative assessments performed. Participants will then have their preoperative MRI request given to them to have this testing done. This will then be used to manufacture their patient specific instrumentation (PSI). These instruments are made specific to the patients anatomy so that during the surgery bony cuts can be made accurately according to the preoperative alignment plan.

2) Surgical Procedure
Surgical technique will be standardized with respect to the resection of bone, ligament tension assessment and use of Verasense instrumentation; The Verasense insert will be used intra-operatively to measure the medial compartment (inside side of the knee) pressures and lateral compartment (outside side of the knee) pressures during the prosthesis trialing phase, before any soft tissue releases are performed. If the knee is not balanced, then measured steps will be undertaken to achieve 'balance’. All intra-operative surgical data will be recorded. All participantss will receive a PSI Nexgen Cruciate Retaining (CR) Flex total knee prosthesis, manufactured by Zimmer. Surgery will be performed by consultant orthopaedic surgeons with more than 10 years of operating experience.

Post-operative Assessment
Post-operative participant review will be conducted in person at consultant clinics by the surgeon and their practice nurses at two weeks, six weeks, six months, and then yearly. Standard TKA post-operative radiologic assessment will be undertaken to determine the final prosthesis alignment
Intervention code [1] 296478 0
Treatment: Surgery
Intervention code [2] 296548 0
Treatment: Devices
Comparator / control treatment
As explained the Arm 2 of the study is a Mechanical Alignment method. Mechanical alignment is the most widely used and classical method of alignment and thus it will act as the control.
Alignment method:
a)The pathological or diseased mechanical alignment is first calculated using long leg x-rays of the patient. This is done on a picture archiving and communicating system (PACS). On the programme we use their circle tool to find the centre of rotation of the hip by drawing a circle that matches the femoral (thigh bone) head. The programme already marks the centre of this circle. A line is drawn from this centre to the highest point of the femoral notch (a crest seen on the x ray near the knee). A second line is drawn from the middle of the tibial spines (top of the tibia) down to the middle of the ankle. The angle between these two lines found. The aim is to make the leg straight, that is, to make this angle that we have found to be 180 degrees after surgery. Therefore, a plan is made to make the tibial and femoral cuts to adjust together to make this angle 180 degrees. If they knee is straight, then during surgery this is checked using the Verasense pressure device, that will tell us that the pressure on both sides of the knee i.e. the medial and lateral compartment pressures are equal.

b) this alignment calculation and the surgical procedure itself is carried out by the consultant surgeons who have at least 10 years of surgical experience performing this surgery.

c) The prosthesis (knee replacement) that will be used is a Patient Specific Instrumented (PSI) Nexgen Cruciate Retaining (CR) Flex prosthesis, manufactured by Zimmer.

d)The procedure will take approximately 1.5 hours to complete.
Control group
Active

Outcomes
Primary outcome [1] 300322 0
Compartment pressures (Primary Outcome)
1) Medial compartment and lateral compartment pressure (in pounds per square inch) at 10 degrees, 45 degrees and 90 degrees of flexion of the knee

Method: The Verasense device sits between the thigh and shin bone components of the trial prosthesis before the final prosthesis is placed. It has a separate screen that shows pressures in real-time and where those pressures are located over the device, thus indicating where these pressures will be when the final prosthesis is placed. These change as the knee is taken through its range of motion. Thus we will not the pressures at the difference degrees of flexion of the knee.
Timepoint [1] 300322 0
Intraoperatively
Primary outcome [2] 300374 0
Rollback patterns (Primary Outcome)
a) Lateral Rollback (medial pivot)
b) Equal Rollback (neutral pivot)
c) Medial Rollback (lateral pivot)

Method: As explained above for primary outcome [1], the Verasense device shows how the pressures change and how the contact point of the knee changes as the knee is bent. If the pressures are greater on the lateral side (outside) of the knee, then the medial side (inside) of the knee will tend to roll back instead of rotating. Hence this is called medial roll back. The opposite is true for the Lateral rollback pattern. Finally if they are equal on both sides then they will equally rollback, giving a neutral pivot. This pattern will be noted intraoperatively from the Verasense screen.
Timepoint [2] 300374 0
Intraoperatively
Primary outcome [3] 300375 0
Verasense contact points (Primary Outcome)
at 0 degrees (full extension) and at 90 degrees. Obtained from the contact tracking map

Method:As explained above for primary outcome [1], the Verasense device shows how the pressures change and how the contact point of the knee changes as the knee is bent. The device also shows where the pressure changes are occurring on the device using a "contact tracking map." The contacts of this map will also be recorded from the device screen.
Timepoint [3] 300375 0
Intraoperativley
Secondary outcome [1] 329684 0
Assessment of Knee range of motion in supine position and active motion. This will be assessed using a digital goniometer.
Timepoint [1] 329684 0
Preoperatively, intraoperatively, after 6 weeks, 6 months, 12 months and 24 months
Secondary outcome [2] 329685 0
Hip Knee Ankle (HKA) angle from preoperative, and posteroperative plain x-rays
Timepoint [2] 329685 0
Preoperatively, intraoperatively, after 6 weeks, 6 months, 12 months and 24 months
Secondary outcome [3] 329688 0
Patient reported outcome measures: ED-5Q Questionnaire. Done when patient visits clinic. Questionnaire takes 5minutes to do.
Timepoint [3] 329688 0
Preoperatively, intraoperatively, after 6 weeks, 6 months, 12 months and 24 months
Secondary outcome [4] 329689 0
Long term prosthesis survival/complication rates, including by not limited to, deep vein thrombosis, periprosthetic fracture, aseptic loosening, septic arthritis, post operative chest pain, postoperative cardiac complications, atelectasis, revision surgery, reoperation, manipulation under anaesthesia. This will be noted in the patients study folder as well their medical record when the patients attends clinic for followup.
Timepoint [4] 329689 0
Postoperatively after 6 weeks, 6 months, 12 months and 24 months
Secondary outcome [5] 329815 0
Soft Tissue adjustments and bone resections (Primary Outcome)
a) Ligament releases: Iliotibial band (ITB), Lateral collateral ligament (LCL), lateral retinaculum, popliteus tendon, posterior cruciate ligament (PCL), Medial collateral ligament (MCL), Semimembranosus (SM)
b) Type of release: complete release, pie crusting (light adjustment with needle)
c) Bone resection adjustment: Coronal alignment of distal femoral cut, coronal alignment of proximal tibial cut, Sagittal alignment of proximal tibial cut, medial tibial reduction osteotomy
Timepoint [5] 329815 0
Intraoperatively
Secondary outcome [6] 329816 0
Patient reported outcome measures: KOOS (includes WOMAC) Questionnaire. Done when patient visits clinic. Questionnaire takes 5minutes to do.
Timepoint [6] 329816 0
Preoperatively, intraoperatively, after 6 weeks, 6 months, 12 months and 24 months
Secondary outcome [7] 329817 0
Patient reported outcome measures: Oxford Knee Score Questionnaire. Done when patient visits clinic. Questionnaire takes 5minutes to do.
Timepoint [7] 329817 0
Preoperatively, intraoperatively, after 6 weeks, 6 months, 12 months and 24 months
Secondary outcome [8] 329818 0
Patient reported outcome measures: Knee Society Knee Score (Pain and function) Questionnaire. Done when patient visits clinic. Questionnaire takes 5minutes to do.
Timepoint [8] 329818 0
Preoperatively, intraoperatively, after 6 weeks, 6 months, 12 months and 24 months

Eligibility
Key inclusion criteria
Male or Female
Age 45-80 years of age
BMI<40
Patients who require primary TKA for treatment of osteoarthritis
Minimum age
45 Years
Maximum age
80 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Previous open knee surgery
Previous high tibial osteotomy
Previous ligamentous injury to the collateral ligaments
Previous fracture of the tibia or femur
Varus or valgus deformity >15 degrees
Fixed tibial subluxation due to posterior bone wear
Hyperextension deformity

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)
Recruitment at surgeons rooms at time of booking for surgery
Concealed in opaque envelopes to allocate to groups
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using Microsoft Excel to randomly assign a sequence and then at the time point of recruitment a concealed opaque envelope system
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Sample Size
A recent study(1) looking at kinematic versus mechanical alignment using PSI was found a Knee Society Score change of 12 points and a standard deviation of 18 points. Assuming Type I error (alpha) to 5% (p = 0.05) and Type II error (beta) to 0.2 (power equal to 80%); for a two sided 5% significance level mean difference of 12 points and standard deviation of 12 points, we can use a sample size table to estimate the sample size to 64 knees in each group. We will investigate 70 knees to compensate for 10% expected loss to follow-up. As we have 4 consultants working on the study, for better division of work we will increase this to 80 in each group participants; overall total of 160 participants in the study.
An interim analysis on Verasense intra-operative assessment data between kinematic and mechanical alignment when n=40 will provide an indication on whether the sample size will be sufficient to show significant effect, and after that no further recruitment will be required.

Analysis of data concluded a reduced sample size was required to reach significance, n=124.

Statistical analysis
Data will be de-identified (non-identifiable) and sent to a statistician to perform analysis. Statistical analysis will be performed using Statistical Sciences (SPSS, Version 22). We will do simple means and calculate standard deviations to assess for average and spread of data. For the primary outcomes we will use independant student T test to compare the two groups.

Reference
1. Calliess T, Bauer K, Stukenborg-Colsman C, Windhagen H, Budde S, Ettinger M. PSI kinematic versus non-PSI mechanical alignment in total knee arthroplasty: a prospective, randomized study. Knee Surgery, Sport Traumatol Arthrosc [Internet]. 2016; Available from: http://link.springer.com/10.1007/s00167-016-4136-8

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/02/2017
Actual
27/06/2017
Date of last participant enrolment
Anticipated
1/12/2019
Actual
6/03/2019
Date of last data collection
Anticipated
1/12/2021
Actual
3/03/2020
Sample size
Target
124
Accrual to date
Final
124
Recruitment in Australia
Recruitment state(s)
QLD
Recruitment hospital [1] 6993 0
Mater Hospital Pimlico - Pimlico
Recruitment hospital [2] 6994 0
Cairns Private Hospital - Cairns
Recruitment hospital [3] 6995 0
Cairns Base Hospital - Cairns
Recruitment postcode(s) [1] 14724 0
4810 - Pimlico
Recruitment postcode(s) [2] 14725 0
4870 - Cairns

Funding & Sponsors
Funding source category [1] 295065 0
Charities/Societies/Foundations
Name [1] 295065 0
The Orthopaedic Research Institute of Queensland (ORIQL)
Country [1] 295065 0
Australia
Primary sponsor type
Charities/Societies/Foundations
Name
The Orthopaedic Research Institute of Queensland (ORIQL)
Address
7 Turner Street, Pimlico QLD 4812
Country
Australia
Secondary sponsor category [1] 293876 0
None
Name [1] 293876 0
Nil
Address [1] 293876 0
Nil
Country [1] 293876 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 296408 0
Townsville Hospital and Health Service Human Research Ethics Committee
Ethics committee address [1] 296408 0
Townsville Hospital and Health Service Human Research Ethics Committee
The Townsville Hospital
100 Angus Smith Drive
Douglas QLD 4814
Ethics committee country [1] 296408 0
Australia
Date submitted for ethics approval [1] 296408 0
10/10/2016
Approval date [1] 296408 0
03/11/2016
Ethics approval number [1] 296408 0
HREC/16/QTHS/205

Summary
Brief summary
The primary aim of this project is to determine the influence of two different prosthesis alignment techniques in total knee arthroplasty (TKA) on the soft tissue balance of the knee by using a novel pressure sensor device. Our hypothesis is, that the kinematic alignment of a total knee prosthesis creates a more balanced knee without the need for soft tissue releases.

The secondary aim of the project is to determine what relationship prosthesis alignment technique has on patient satisfaction and on patient reported outcome measures (PROMs).

The proposed research design is a multi-site, single blinded, prospective randomized controlled trial involving four consultant orthopaedic surgeons at the Mater Health Services North Queensland Ltd, Cairns Base Hospital and the Cairns Private Hospital.

Participants will be randomized to either mechanical or kinematic alignment. All participants will undergo the same peri-operative and post-operative protocol process for TKA. All procedures will be planned and performed with the use of patient specific instrumentation (PSI) custom cutting guides based on a pre-operative MRI. These allow the surgeon to make pre-planned bone resections specific to the participant's anatomy. All participants will receive the same total knee prosthesis. The surgical technique will be standardized with respect to the resection of bone, ligament tension assessment and the use of Verasense instrumentation. The Verasense insert will be used intra-operatively to measure pressures across the knee joint during the prosthesis trialing phase, before any soft tissue releases are performed. If the knee is not balanced, then measured steps will be undertaken to achieve balance. All intra-operative surgical data will be recorded. Post-operative patient review will be conducted at two weeks, six weeks, six months, and then yearly. Standard TKA post-operative radiologic assessment will be undertaken to determine the final prosthesis alignment. Outcome measures will include validated clinical pain and function scores such as the WOMAC score, EQ5D, Knee Society Score, the Oxford Knee Score, and the Forgotten Joint Score.

Data collected will be analysed using statistical methods in order to find any statistically significant difference in results between the two alignment strategies. Once collected, data will be de-identified (non-identifiable) and sent to an external statistician to perform statistical analysis. All participants will receive PSI Zimmer Nexgen CR Flex TKA prosthesis.
Trial website
Trial related presentations / publications
Public notes
Attachments [1] 1267 1267 0 0
/AnzctrAttachments/371917-Ammended Verasense KVM Study Protocol Version 24 Oct 2016.docx (Protocol)
Attachments [2] 1268 1268 0 0
/AnzctrAttachments/371917-16QTHS205_3 Approved.pdf (Ethics approval)
Attachments [3] 1269 1269 0 0
/AnzctrAttachments/371917-Patient_Information_Statement_KVM_-_Version_1.2.docx (Participant information/consent)
Attachments [4] 1270 1270 0 0
/AnzctrAttachments/371917-Ammended Consent Form Verasense KVM Version 1.2 .docx (Participant information/consent)
Attachments [5] 1271 1271 0 0
/AnzctrAttachments/371917-Master Unspecified Consent Form.docx (Participant information/consent)
Attachments [6] 1272 1272 0 0
/AnzctrAttachments/371917-Master Withdrawal of Consent Form.docx (Participant information/consent)

Contacts
Principal investigator
Name 70726 0
Mrs Andrea Grant
Address 70726 0
The Orthopaedic Research Institute of Queensland
7 Turner Street
Pimlico QLD 4812
Country 70726 0
Australia
Phone 70726 0
+61747550564
Fax 70726 0
Email 70726 0
[email protected]
Contact person for public queries
Name 70727 0
Andrea Grant
Address 70727 0
The Orthopaedic Research Institute of Queensland
7 Turner Street
Pimlico QLD 4812
Country 70727 0
Australia
Phone 70727 0
+61747550564
Fax 70727 0
Email 70727 0
[email protected]
Contact person for scientific queries
Name 70728 0
Andrea Grant
Address 70728 0
The Orthopaedic Research Institute of Queensland
7 Turner Street
Pimlico QLD 4812
Country 70728 0
Australia
Phone 70728 0
+61747550564
Fax 70728 0
Email 70728 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
The participant data will all remain in a private database.


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.