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Trial registered on ANZCTR


Registration number
ACTRN12620000310965p
Ethics application status
Submitted, not yet approved
Date submitted
10/01/2020
Date registered
6/03/2020
Date last updated
6/03/2020
Date data sharing statement initially provided
6/03/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
Does cooled radiofrequency ablation improve postoperative pain and function in patients undergoing total knee replacement surgery? A randomized controlled trial.
Scientific title
Does cooled radiofrequency ablation improve postoperative pain and function in patients undergoing total knee arthroplasty? A randomized controlled trial.
Secondary ID [1] 300156 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis 315695 0
Total knee arthroplasty 316495 0
Condition category
Condition code
Surgery 313980 313980 0 0
Other surgery
Musculoskeletal 314742 314742 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
All patients will undergo a TKA via the surgeon’s standard technique. All patients will have a general anaesthetic, with intravenous analgesia during the operation as deemed appropriate by the anaesthetist. Antibiotic prophylaxis (cephazolin 2g) will be administered within 30 minutes of skin incision. All patients will be positioned supine on a standard operating table and the skin will be cleaned with antiseptic solution and covered with sterile drapes. For all cases, a tourniquet set at 300mgHg will be used. The operation will be performed using a midline incision and a medial parapatellar approach. Computer navigation software will be used for intra-operative guidance on alignment and prosthesis positioning (as is standard for the surgeon). The patella will be resurfaced in all cases as is routine for the surgeon involved. All patients will have local anaesthetic infiltration using 0.2% ropivacaine; all patients will receive the same dose. No suction drains will be used. The wounds will be closed in layers with an absorbable monofilament used for skin closure.

The intervention will be the use of the cooled radiofrequency ablation (C-RFA) procedure of the knee in conjunction with total knee replacement (TKR) surgery. This is a procedure used for relief of pain and is a procedure commonly performed by the surgeon involved in the study. The procedure will occur in the operating theatre, once the patient is anaesthetised, prior to the commencement of the TKA operation. They will undergo four genicular nerve C-RFA. It is estimated this will add 5-10 minutes to the total operation time. This will be performed using the Avanos Coolief Radiofrequency System which will be performed with the surgeon’s standard technique, in keeping with manufacturer’s guidelines. Using fluoroscopic guidance, the surgeon will identify four anatomical bony landmarks which represent the target sites for the four genicular nerves. An insulated electrode needle will be inserted through the skin and placed within the tissues at this location and target positioning will be confirmed again with fluoroscopy. Sensory and motor testing will be performed to again confirm placement (as is recommended practice). At this stage, the radiofrequency generator will be turned on which will transmit a current of radiofrequency energy at a maximum of 0.5V through the insulated electrode. Due to the friction of charged molecules heating occurs with the generator set temperature of 60 degrees imparting a tissue temperature of 80 degrees celsius, which thermally deactivates the nerves responsible for sending pain signals to the brain. The radiofrequency energy is delivered through water-cooled electrodes, enabling more energy to be safely delivered to the target. The needle is then removed and this process will be repeated for all four locations.

Patients are able to weight-bear as tolerated post-operatively. Standardised post-operative analgesia regimens will be followed and physiotherapy will be commenced on day 1 post-operatively. Patient outcomes (as described) will be recorded.

During the procedure the surgeon responsible, being an investigator in the study, will identify and document any adverse events which occur. At each follow up point in the study an investigator will assess the participant and again document any adverse events which occur.
Intervention code [1] 316430 0
Treatment: Surgery
Comparator / control treatment
All participants will be having total knee replacement surgery. In the control group, participants will undergo standard TKR as described above in addition to a sham intervention (replicating the C-RFA procedure). For this group, at the conclusion of the operation, following wound closure, a 21g needle will be used to pierce the skin at four locations corresponding to those used in RFA. This will be inserted through skin (epidermis) only (not deep as in RFA). This is expected to be less invasive and less traumatic than a simple peripheral intravenous cannula insertion. A large dressing will then be placed over the TKA wound, as well as four small dressings placed over the needle insertion sites. This will ensure blinding of patients is not compromised by recognising RFA pin sites, or lack thereof. Post-operative management will be the same as the intervention group, as described above.
Control group
Placebo

Outcomes
Primary outcome [1] 322404 0
Clinical and functional result assessed via the Western Ontario and McMaster Universities Index (WOMAC) score.
Timepoint [1] 322404 0
This will be assessed at post-operative weeks 2, 6 and 12 (primary timepoint). The WOMAC is a 24-item questionnaire with 3 sub-scales measuring pain, stiffness and physical function. The WOMAC has been validated for measuring outcomes in clinical trials of TKR and takes approximately 10 minutes to complete. This will be completed by a designated assessor at outpatient clinic appointments at the 2, 6 and 12 week mark.
Primary outcome [2] 322405 0
Patient-reported pain scores assessed using the 0-100 Visual Analogue Scale for Pain (VAS Pain).
Timepoint [2] 322405 0
3 months post surgery. This will be assessed at post-operative day 1, post-operative day 2, and weeks 2, 6 and 12 (primary timepoint).
Secondary outcome [1] 378375 0
Functional outcome assessed using the Timed Up & Go Test.
Timepoint [1] 378375 0
This will be assessed at post-operative weeks 2, 6 and 12. The Timed Up & Go Test is measured by timing the patient to move from a sitting position in a chair, to a piece of tape on the floor three meters directly in front of them, and back to a sitting position in a chair (standardised verbal instructions will be provided as well as a single practice at doing this task). This will be assessed by a designated assessor at outpatient clinic appointments at the 2, 6 and 12 week mark.
Secondary outcome [2] 378376 0
Clinical and functional result of the surgery assessed using the Oxford Knee Score (OKS).
Timepoint [2] 378376 0
3 months post surgery. This will be assessed at post-operative weeks 2, 6 and 12 during outpatient clinic appointments. The OKS is a knee joint specific 12-item questionnaire validated for use in randomized controlled trials in TKA. The OKS takes approximately 5 minutes to complete.
Secondary outcome [3] 378377 0
Operative time
Timepoint [3] 378377 0
Operative time will be measured and recorded by a designated staff member in the operative team. This will be recorded at time from initial skin incision to wound closure, or skin incision to final RFA completion in the intervention group.
Secondary outcome [4] 380750 0
Clinical and functional result of the surgery assessed using the SF-12 score.
Timepoint [4] 380750 0
3 months post surgery. This will be assessed at post-operative weeks 2, 6 and 12 during outpatient clinic appointments. The Short-Form 12 (SF-12) is a 12-item health questionnaire to assess general health and well-being.
Secondary outcome [5] 380751 0
Active knee range of motion
Timepoint [5] 380751 0
Active knee range of motion will also be assessed at post-operative weeks 2, 6 and 12 using a goniometer with the patient in the supine position.
Secondary outcome [6] 380752 0
Length of hospital stay
Timepoint [6] 380752 0
Length of hospital stay will be recorded by a designated assessor. This will be done via prospectively collected medical records.

Eligibility
Key inclusion criteria
- Elective primary unilateral TKR surgery performed by A/Prof Paul Harvie
- Diagnosis of knee osteoarthritis
- Age 18-85 years
- Provide consent to participate in the study and comply with the study protocol
Minimum age
18 Years
Maximum age
85 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
- Patients who have had previous osteotomies or fractures of the distal femur or proximal tibia
- Unwillingness or inability to comply with study protocol or follow up requirements
- Subjects taking regular (daily) opiate medication pre-operatively
- Subjects with moderate or severe psychiatric illness
- Subjects deemed by the anaesthetist as not suitable for a general anaesthetic
- Any contraindication to the routine postoperative analgesic medication regimen as outlined in the study protocol or deemed by the anaesthetist to be not suitable for this regimen

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)
Allocation is concealed. Allocation will be done via central computer-generated randomisation. At the time of determining eligibility, the researcher will be unaware of the participant's allocation.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a computer-generated table.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
All analyses will be performed with the use of a statistical software package (SPSS). As our primary outcome measure will be the WOMAC score at 3 months postoperatively, this will be used as the basis of our sample size calculation. A difference in WOMAC scores of 15-points between groups has been suggested as the minimal clinically important difference (Escobar 2007). Based on the statistical power of 80% to detect a significant difference (2-sided, p=0.05), 28 patients will be required in each study group. To account for up to 20% of participants lost to follow of up, 34 patients will be recruited to each group.

All analyses will be conducted according to the intention-to-treat principle. Baseline data will be examined for differences. Student’s t-test will be used for continuous data to determine differences between the two treatment groups. Chi-square tests will be used for analyses of categorical data and when continuous data are not normally distributed.

Recruitment
Recruitment status
Not yet 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)
TAS
Recruitment hospital [1] 15570 0
Royal Hobart Hospital - Hobart
Recruitment postcode(s) [1] 28944 0
7000 - Hobart

Funding & Sponsors
Funding source category [1] 304595 0
Hospital
Name [1] 304595 0
Royal Hobart Hospital
Address [1] 304595 0
Department of Orthopaedics, Royal Hobart Hospital, 48 Liverpool St, Hobart, TAS, 7000.
Country [1] 304595 0
Australia
Primary sponsor type
Hospital
Name
Department of Orthopaedics, Royal Hobart Hospital.
Address
48 Liverpool St, Hobart, TAS, 7000.
Country
Australia
Secondary sponsor category [1] 304885 0
None
Name [1] 304885 0
N/A
Address [1] 304885 0
N/A
Country [1] 304885 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 305017 0
University of Tasmania Tasmania Health and Medical Human Research Ethics Committee
Ethics committee address [1] 305017 0
Office of Research Services, University of Tasmania, Private Bag 1, Hobart, TAS, 7001
Ethics committee country [1] 305017 0
Australia
Date submitted for ethics approval [1] 305017 0
08/11/2019
Approval date [1] 305017 0
Ethics approval number [1] 305017 0

Summary
Brief summary
This study is a prospective randomised controlled trial investigating whether the use of cooled radiofrequency ablation in total knee arthroplasty improves postoperative pain and postoperative function.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 98982 0
Dr Matthew Free
Address 98982 0
Department of Orthopaedics, Box Hill Hospital, 8 Arnold Street, Box Hill, VIC, 3128.
Country 98982 0
Australia
Phone 98982 0
+61 407314302
Fax 98982 0
Email 98982 0
mdfree05@gmail.com
Contact person for public queries
Name 98983 0
Dr Matthew Free
Address 98983 0
Department of Orthopaedics, Box Hill Hospital, 8 Arnold Street, Box Hill, VIC, 3128.
Country 98983 0
Australia
Phone 98983 0
+61 407314302
Fax 98983 0
Email 98983 0
mdfree05@gmail.com
Contact person for scientific queries
Name 98984 0
Dr Matthew Free
Address 98984 0
Department of Orthopaedics, Box Hill Hospital, 8 Arnold Street, Box Hill, VIC, 3128.
Country 98984 0
Australia
Phone 98984 0
+61 407314302
Fax 98984 0
Email 98984 0
mdfree05@gmail.com

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
No other documents available
Summary results
No Results