Trial Review

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12616001706460
Ethics application status
Approved
Date submitted
17/10/2016
Date registered
13/12/2016
Date last updated
16/07/2021
Date data sharing statement initially provided
27/02/2020
Date results information initially provided
27/02/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
In individuals undergoing simultaneous bilateral total knee replacement, does making a lateral skin incision affect skin sensation, ability to kneel and patient satisfaction?
Scientific title
In individuals undergoing simultaneous bilateral total knee replacement, does making a lateral skin incision affect skin sensation, ability to kneel and patient satisfaction.
Secondary ID [1] 289737 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis 299580 0
Total knee arthroplasty 299581 0
Condition category
Condition code
Surgery 299547 299547 0 0
Surgical techniques
Musculoskeletal 299550 299550 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients will undergo a total knee replacement in both knees to treat osteoarthritis. Two different skin incisions will be used. The study exposure called the lateral incision. It is an incision that starts 5cm midline above the patella (knee cap) and as is curved inferiorly (down the knee) and laterally (the outer side edge) around the patella. It finishes curving back once passed the patella towards the midline of the tibia (shin). (Please see study protocol attached to ANZCTR registration form for images.) We hypothesize that the more lateral or towards the outside of the knee the incision is, the less insensate skin on the outer side of the knee will be and the patient will be able to kneel better. The lateral skin incision will be performed with a scalpel. Deeper dissection will be performed with diathermy cautery. Skin flaps will be mobilised. A midvastus medial parapatellar arthrotomy will be done and the knee joint exposed with the patella flipped laterally Computer navigation will be used. The surgery will take 60-90 minutes.
Intervention code [1] 295373 0
Treatment: Surgery
Comparator / control treatment
Patients will undergo a total knee replacement in both knees to treat osteoarthritis. Two different skin incisions will be used, the control group will be the opposite knee with an incision centred in the middle of the knee . Computer navigation will be used. The surgery will take 60-90 minutes.
Control group
Active

Outcomes
Primary outcome [1] 299029 0
Skin sensation to knee area as measured by pin prick testing and area drawn on skin. Photo of area will be taken with scale included in the image. Area will be measured using a open source image analysis software using the scale to calibrate the area.
Timepoint [1] 299029 0
6 months post-operatively, 12 months post-operatively
Primary outcome [2] 299030 0
Kneeling ability- graded using a novel grading system for each knee, defined as able to get to grading position and then get to standing position. Grading is as follows
Grade 1) Partial squat (knee flexes above 90 degrees)
Grade 2) Full squat (knee flexes down past 90 degrees)
Grade 3) Split kneel (study knee on floor flexed to 90 degrees and contralateral knee flexed to 90 degrees with foot on floor)
Grade 4) 90 degrees kneel (both knees flexed to 90 degrees on the floor
Grade 5) Full kneel (both knees on floor, knees flexed past 90 degrees, sitting back on haunches)
Timepoint [2] 299030 0
Baseline (pre-operatively), 6 weeks post-operatively, 12 months post-operatively
Primary outcome [3] 299031 0
Pain relief requirement, graded using the grades:
1) None - nil/ice pack/heat pack
2) Mild - occasional NSAID use
3) Moderate - Regular NSAID use
4) Severe - Regular NSAID use + breakthrough occasional opiate use
5) Very Severe - Regular NSAID use + Opiate Use
Timepoint [3] 299031 0
6 months post-operatively, 12 months post-operatively
Secondary outcome [1] 325903 0
Range of motion (limits of flexion and extension as a composite outcome), as assessed by the surgeon using a digital inclinometer,
Timepoint [1] 325903 0
Baseline (Pre-operative), 6 months post-operatively, 12 months post-operatively
Secondary outcome [2] 325904 0
Length of scar in centimetres
Timepoint [2] 325904 0
6 months post-operatively, 12 months post-operatively
Secondary outcome [3] 325905 0
KOOS - junior (Validated outcome score)
Timepoint [3] 325905 0
Baseline (Pre-operative), 6 months post-operatively, 12 months post-operatively
Secondary outcome [4] 325906 0
Oxford Knee Score (Validated outcome score)
Timepoint [4] 325906 0
Baseline (Pre-operative), 6 months post-operatively, 12 months post-operatively
Secondary outcome [5] 325907 0
Visual-analogue scale pain score (Validated outcome score)
Timepoint [5] 325907 0
Baseline (Pre-operative), 6 months post-operatively, 12 months post-operatively
Secondary outcome [6] 325908 0
Kujala Anterior Knee Pain score (Validated outcome score)
Timepoint [6] 325908 0
Baseline (Pre-operative), 6 months post-operatively, 12 months post-operatively
Secondary outcome [7] 325909 0
Forgotten Joint Score (Validated Outcome Score)
Timepoint [7] 325909 0
Baseline (Pre-operative), 6 months post-operatively, 12 months post-operatively
Secondary outcome [8] 325911 0
5Q-5D (Validated Outcome score)
Timepoint [8] 325911 0
Baseline (Pre-operative), 6 months post-operatively, 12 months post-operatively
Secondary outcome [9] 325913 0
Composite Outcomes collected using Computer assisted surgery data recorded from the Navigation system during the surgery.
1. Navigated alignment
2. Tibial slope
3. Degree of flexion and extension
4. Tibial and femoral cuts
5. Medial and lateral flexion and extension gaps
6. Varus/valgus alignment
7. Internal/external rotation
8. Size of tibial and femoral implant
Timepoint [9] 325913 0
Data will be collected using Navigation intraoperatively

Eligibility
Key inclusion criteria
Patients scheduled to undergo bilateral knee arthroplasty
Male and female
Age 40-90
Able to provide informed consent
Minimum age
40 Years
Maximum age
90 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Conditions causing altered sensation up to knee- Diabetic Neuropathy, regional pain syndrome
Previous open surgical procedure to knee
Patients with inflammatory arthritis
Patients not suitable for patella resurfacing

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 opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
We will generate a random sequence of numbers using an online random number generator. This sequence will be used to allocate participants to a study group.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
We will de-identify data and send it to an external statistician to perform the appropriate statistical testing. To perform a sample size calculation, we used a study by Borely et al. The expected surface area of loss of skin innervation in midline skin incisions in TKA was found to be of mean of 66cm2 with a standard deviation (SD) of 30 cm2. As there is are no published observational data for lateral skin incisions, we assumed the loss of skin sensation of 44cm2 with same SD of 30 cm2 with lateral skin incisions. Assuming Type I error (alpha) to 5% (p = 0.05) and Type II error (beta) to 0.2 (power equal to 80%), the sample size calculated was 30 knees in each group, therefore 60 knees. We will investigate 66 knees to compensate for 10% expected loss to follow-up. As we are using bilateral knees, we will need 33 patients.

We will use SPSS software to analyse the data. For the continuous data such as the area of reduced sensation will use repeated measures ANOVA. The difference in the means of the PROMs data, as well as the kneeling grade will determined using the non-parametric Wilcoxon’s signed- rank test for non-normally distributed data, an unpaired t-test for normally distributed data.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/02/2017
Actual
19/06/2017
Date of last participant enrolment
Anticipated
30/12/2018
Actual
21/03/2019
Date of last data collection
Anticipated
31/03/2020
Actual
21/03/2020
Sample size
Target
33
Accrual to date
Final
33
Recruitment in Australia
Recruitment state(s)
QLD
Recruitment hospital [1] 6655 0
Mater Hospital Pimlico - Pimlico
Recruitment postcode(s) [1] 14280 0
4810 - Pimlico

Funding & Sponsors
Funding source category [1] 294511 0
Other Collaborative groups
Name [1] 294511 0
The Orthopaedic Research Institute of Queensland
Country [1] 294511 0
Australia
Primary sponsor type
Other Collaborative groups
Name
The Orthopaedic Research Institute of Queensland (ORIQL
Address
7 Turner St, Pimlico, QLD 4812
Country
Australia
Secondary sponsor category [1] 293375 0
None
Name [1] 293375 0
Address [1] 293375 0
Country [1] 293375 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 295943 0
Mater Hospital Pimlico Human Research Ethics Committee
Ethics committee address [1] 295943 0
Chairperson
Human Research Ethics Committee
Mater Health Services North Queensland Ltd
21-29 Fulham Rd,
Pimlico, Townsville QLD 4812
Ethics committee country [1] 295943 0
Australia
Date submitted for ethics approval [1] 295943 0
08/08/2016
Approval date [1] 295943 0
14/12/2016
Ethics approval number [1] 295943 0
MHS20161122-01

Summary
Brief summary
The initial skin incision performed to expose the knee during total knee arthroplasty (TKA) is centred over the patella for ease of access to the joint. This places the scar directly over the bony points of the knee that bear load when kneeling, leaving the skin on the lateral side (outside) of the scar with reduced sensation and sometimes the skin on the medial side (inside) of the scar with painfully altered sensation (dysaesthesiae / neuromata). Placing the skin incision lateral to the edge of the patella (kneecap) avoids the necessity of kneeling on a scar and has been shown to reduced dysaesthesiae and neuromata in other knee procedures.

Primary Aim:
To prove that lateral skin incisions improve the ability to kneel in patients following bilateral total knee arthroplasty

Secondary Aim:
1.Investigate whether lateral skin incision has improved retention of skin sensation.
2.Investigate the ability to kneel after TKA.
3.Investigate if there is improved deep flexion.
4.Investigate whether there is decreased pain and better satisfaction as per patient reported outcome measures (PROM)

Research Design:
Prospective, Randomized Controlled Trial.

Patient Demographic: Eligible patients aged between 40-90 years of age with bilateral, tri-compartmental osteoarthritis (OA),undergoing simultaneous bilateral TKA. Patients with previous knee arthrotomy (cut to the joint capsule) will be excluded.

Patients' limbs will be randomized for surgery into two groups; (1) Midline Incision Group and (2) Lateral Incision Group.

Outcomes:measured at, six months, and 12 months post-operatively.
- Knee flexion and extension.
- Kneeling Grade Assessment- a novel grading system has been developed that Grades the ability to kneel from 1-5 depending on how far down the patient can knee.
- Area of skin dysaesthesia (uncomfortable change in skin sensation) will be mapped and analyzed using imaging software.
- Neuroma formation.
- PROMs (patient reported outcome measures).
Trial website
Trial related presentations / publications
Public notes
Attachments [1] 1110 1110 0 0
/AnzctrAttachments/371143-Study Protocol Lateral skin incision v2.3 update 21072016.docx (Protocol)
Attachments [2] 1111 1111 0 0
/AnzctrAttachments/371143-Participant Information Form Lateral Incision version 1.1 updated 21072016.docx (Participant information/consent)

Contacts
Principal investigator
Name 67630 0
Dr Peter McEwen
Address 67630 0
North Queensland Knee, Orthopaedic Research Institute of Queensland (ORIQL)
Suite 3, Level 2, Mater Medical Centre 21-29 Fulham Rd, Pimlico, QLD 4812
Country 67630 0
Australia
Phone 67630 0
+61747794788
Fax 67630 0
Email 67630 0
[email protected]
Contact person for public queries
Name 67631 0
Mrs Andrea Grant
Address 67631 0
The Orthopaedic Research Institute of Queensland
7 Turner Street, Pimlico, QLD 4812
Country 67631 0
Australia
Phone 67631 0
+61747550564
Fax 67631 0
Email 67631 0
[email protected]
Contact person for scientific queries
Name 67632 0
Mrs Andrea Grant
Address 67632 0
The Orthopaedic Research Institute of Queensland
7 Turner Street, Pimlico, QLD 4812
Country 67632 0
Australia
Phone 67632 0
+61747550564
Fax 67632 0
Email 67632 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
All data will remain in a private database, in a de-identified but re-identifiable format.

We have not yet worked out a platform on which to share the data, or the appropriate data to be shared. Our research group is currently in the in the process of coming to an agreement on this.


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
SourceTitleYear of PublicationDOI
EmbaseSkin sensory alteration and kneeling ability following cruciate retaining total knee arthroplasty are not affected by the incision position: A randomised controlled trial of simultaneous bilateral surgery.2023https://dx.doi.org/10.1186/s40634-023-00695-9
N.B. These documents automatically identified may not have been verified by the study sponsor.