Clinical Trial Details
— Status: Active, not recruiting
Administrative data
| NCT number |
NCT03563131 |
| Other study ID # |
PERSONA-RH-18 |
| Secondary ID |
|
| Status |
Active, not recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
August 1, 2018 |
| Est. completion date |
December 31, 2025 |
Study information
| Verified date |
May 2023 |
| Source |
Rigshospitalet, Denmark |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
The purpose of this study:
In a prospective randomized study with 2 years of follow-up we want to compare the migration
of the uncemented trabecular metal (TM) versus the cemented tibial and femoral components of
the new Persona® total knee arthroplasty (TKA) assessed by model based radiostereometric
analysis (MB-RSA). Also, we want to compare the adaptive bone remodeling induced by the
uncemented TM versus the cemented tibial and femoral components of the new Persona® TKA
assessed by dual energy-X-ray (DEXA). Data generated for both above mentioned, will be also
compared with historical RSA and DEXA data for the NexGen TKA using TM tibia modular and
monoblock.
Description:
Detailed Description: Main Hypothesis:
1. The uncemented TM Zimmer Persona® TKA will have migration on the same level as the
cemented Zimmer Persona® TKA.
2. The uncemented TM Zimmer Persona® TKA will have less loss of BMD compared to the
cemented version of the implant.
Material and Methods:
A prospective randomized study where the patients scheduled for TKA are randomized to receive
tibial and femoral components with two different fixation modes:
Group A: an uncemented TM Zimmer Persona® TKA (uncemented tibia and femur components).
Group B: a cemented Zimmer Persona® TKA (cemented tibia and femur components). Operation:
Operation Planning of the operations are performed based upon standing knee X-rays (not
involving the ankle and hip joint) and no preoperative templating is performed. The
operations are performed at the Department of Orthopedic Surgery, Gentofte Hospital by three
experienced TKA surgeons that will be included in the research group. All patellas will be
resurfaced with a cemented all polyethylene patella component. During surgery the patients
participating in the study will be prepared for MB-RSA by insertion of a minimum of 6
Tantalum markers (0.8 mm) in the bone of the proximal tibia and 6 markers in the distal
femur.
Intravenous antibiotics (1.5g Cefuroxim) are administered three times during the first day
and night of surgery and low molecular weight heparin is administered for prevention of deep
venous thrombosis and pulmonary embolism. Local analgesics (Naropin ®, Toradol ®) are
injected in the knee joint and in the soft tissue around the knee during surgery.
Physiotherapy begins on the day of surgery and the patients will be mobilized with full
weight-bearing using crutches.
Research plan
1. Clinical examination (n=60): preoperatively and with follow-up after 1 and 2 years with
evaluation of the knee function using the Knee Society's Knee Scoring System.
2. Patient-reported outcome measurements (n=60). Obtained preoperatively and after 1 and 2
years using the Oxford knee score.
3. Conventional X-rays (n=60) are obtained preoperatively (standing knee X-rays (not
involving the ankle and hip joint)), with classification of the degree of arthrosis
estimating the Ahlbäck score. X-rays are also obtained postoperatively before the
patients are discharged and after 1 year and 2 years with the aim of evaluating knee
alignment, and development of osteolytic lesions.
4. CT-scans (n=60) 3 months postoperatively for measurements of hip-knee-ankle (HKA) angle,
and component slope, rotation, and size matching.
5. Special X-rays suitable for MB-RSA measurements (n=60) of migration of the tibial and
femoral components is performed within the first week after the operation and after 3,
6, 12, and 24 months. The precision of the RSA measurements is estimated from double
examinations in 12 patients of the study. RSA X-rays will be performed using a biplane
RSA arrangement with a 90° angle between the two X-ray tubes (Calibration cage 21; Tilly
Medical Products AB, Lund, Sweden) and analysis of X-rays will be performed by the
MB-RSA commercial software (RSAcore, Department of Orthopedics, Leiden University
Medical Center, Leiden, The Netherlands), available at the Skaane University Hospital,
Lund, Sweden. The manufacturer (Zimmer Biomet) will provide the CAD models.
6. DEXA analysis of the adaptive changes in BMD of the periprosthetic bone of the distal
femur and proximal tibia. DEXA analysis will be performed preoperatively of the distal
femur (lateral projection) and proximal tibia (coronal projection) as baseline, then
again within the first postoperative week and subsequently at 3 months, 6 months, 1
year, and 2 years. The precision of the BMD measurements of the proximal tibia and
distal femur will be estimated from double measurements of patients (n=12) included in
the study.
Calculation of sample size MB-RSA There exist only three previously published studies
measuring femoral component migration. In all studies the marker-based RSA technique was
used, and none of them presented results with mean and standard deviation (SD). However, one
study gave the results as mean MTPM, and we chose the mean MTPM after 2 years of follow-up
(0.88 mm for cemented components) as our primary effect parameter, used in the sample size
calculation. The rationale for using MTPM two years postoperatively, is because it has been
shown to be the best predictor for later aseptic loosening of the tibial component after
primary TKA. SD was estimated from the most recently published study using MB-RSA for
evaluation of cemented tibial component migration. In that study, the mean (+/- SD) MTPM
after 2 years of follow-up was 0.47 (+/- 0.16) and 0.45 (+/-0.21) in the two study groups.
Since the level of MTPM of the tibial components was substantially lower than seen for the
above mentioned femoral components. We adjusted the SD in the sample size calculation to
constitute the same percentages of the mean values as in the tibial component MB-RSA study by
Ejaz et al. (2015). Since the previously published studies measuring femoral component
migration did not find any statistically significant difference between cemented and
uncemneted fixation we selected a relatively low minimum relevant difference (MIREDIF).
Using:
Type I error = 5% Statistical power = 85 % MIREDIF 0.3 mm SD = 0.35 mm Sample size
calculation resulted in a sample size of n = 24 in each group. In the study we have planned
to include and randomize (block-randomization with 10 in each block) a total of 60 patients.
This will secure a high statistical power even if some of the participants should drop out
during the study.
DEXA
The data for the sample size calculations were obtained from new DEXA data for our own
research group: data from a study evaluating the adaptive bone remodeling around the
Vanguard® uncemented porous-coated femoral component with one year of follow-up. Using
one-year follow-up data could be justified because the decrease in BMD seen beyond the first
postoperative year is very limited in most studies. We considered a difference of 8% between
groups to be a clinically relevant difference that we wanted to be able to detect with a high
statistical power:
Using:
Type I error = 5% Statistical power = 90 % MIREDIF 8% SD = 8.4% Sample size calculation
resulted in a sample size of n = 25 in each group.
In the study we have planned to include and randomize (block-randomization with 10 in each
block) a total of 60 patients. This will secure a high statistical power even if some of the
participants should drop out during the study.
Ethical considerations We do not expect that the patients participating in the study will
experience any special side effects or complications related to the use of the two TKAs.
There has not been performed any fundamental changes in implant design compared to other
types of standard TKAs and the implant fixation modes (cemented or uncemented with a TM
ingrowth surface) are well known and in wide spread use.
Radiation dose to the patients from MB-RSA X-rays and DEXA is relatively low compared with
many conventional X-ray examinations.The total accumulated radiation dose to a patient
participating in all examinations during the study is estimated to be approximately 2 mSv.
Tantalum has been used for more than 50 years and is a very biocompatible material without
any tendency to corrosion.Tantalum beads for RSA have been used in several clinical studies
for more than 20 years. More than 20.000 beads have been implanted in more than 2.000
patients and no side effects from Tantalum beads have been observed.
This investigation will be performed in accordance with the principles of the Helsinki
Declaration, and all patients will receive both oral and written information before informed
consent to participate is obtained. At any time being the patient will be able to cancel
participation (also without any explanation) in this investigation. The patient will receive
the best possible treatment in any circumstances. The study will not be started until
approval from the Scientific Ethical Committee of the Capital Region of Denmark and the
Danish Data Protection Agency has been obtained, and it will be registered at
clinicaltrials.gov.
Risks and inconveniences:This investigation will not add to the general risks of getting TKA.
Patients participating must accept some inconvenience in terms of additional examinations and
hence transportation to and from the hospitals.
Adverse events: All adverse events will be recorded in the CRF and will include details
concerning the nature, onset, duration, severity, relationship to the device and relationship
to the operative procedure and outcome. The affected patient(s) will be questioned about any
adverse event(s) at each subsequent follow-up visit.
Patients experiencing adverse events will be relevantly monitored by clinical assessment and
lab examinations decided by the treating physician. All adverse events will be monitored
until recovery or stabilization.
Information and consent Patients who are planned to receive a TKA (and fits within the
inclusion and exclusion criteria of the study) at Gentofte Hospital will be informed about
the trial in the preoperative interview. In addition to the oral information provided, the
patients will be given written information. This conversation will take place in an enclosed
space without distractions or interruptions. The patient will receive adequate verbal and
written information about the purposes, processes, potential benefits and risks including
possible side effects. Investigator will ensure all patients have read and understood the
information and consent form. Patients will be informed that they are entitled to
consideration before consent is given. The subjects will also be informed that it is
voluntary and that they at any time may withdraw from the trial. It is the investigator's
responsibility to ensure the above.
There will be obtained written informed consent from all subjects before enrollment, and a
copy of the information and consent form will be given to the subjects.Existing legislations
made by the Scientific Ethical Committee regarding informed consent will be followed.
Data protection All information will be kept confidential, and all data handled according the
guidelines of the Danish Data Protection agency. The persons involved in this trial are
obliged to professional secrecy. The investigator will maintain a list of identification of
all enrolled patients. This list will contain the patients' full names and dates of birth
(including social security numbers (CPR-numbers)).
Collected data will be recorded in a case report form (CRF). CRFs and the medical records
will be made available to third parties according to Danish law. Patients will be informed in
writing that the results will be stored and analyzed in a computer which preserve patients'
anonymity and that the local laws regarding personal data will be complied.
Patients will also receive written information concerning the possibility of audit from the
public authorities, and patients will be informed that the GCP unit of Copenhagen University
Hospital likewise is granted access.
Investigator ensures that the project will follow the rules of Good Clinical Practice
