2.1 Primary objectiveTo compare the wear rate 24 months after THA of HXLPE stabilized with vitamin E versus conventional UHMWPE for total joint arthroplasty.2.2 Secondary objectives1. To compare the wear rate at 3,12 and 24 months after THA between…
ID
Source
Brief title
Condition
- Joint disorders
- Bone and joint therapeutic procedures
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The primary final study point is the polyethylene wear rates. Measuring is
based on anterior-posterior (AP) radiographs at 3,12 and 24 months using a
computer-assisted edge-detection system (ROGAN Delft, VPX ortho)
The software calculates femoral head displacement (mm) and the angle (°) as a
representation of wear.
Secondary outcome
Harris Hip Score, reflecting both function and pain The subjective variables
are pain activities of daily living. The objective variables are range of
motion and hip positioning which give a total of 100 points. ROM includes
flexion, extension, abduction, adduction, external rotation and internal
rotation measured using a goniometer
Pain level will be determined using a 10-point Visual Analog Scale (VAS), in
which 0 implies no pain and 10 implies the worst possible pain.
The Short-Form 36 (SF-36), is a validated multi-purpose, short-form health
survey with 36 questions, representing eight health domains that are combined
into a physical and a mental component scale.
The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) is a
24-item questionnaire completed by the patient and focusing on joint pain,
stiffness and loss of function related to osteoarthritis of hip.
Functional status and activity level will be assessed with the Short
Questionnaire to Assess Health-Enhancing Physical Activity (SQUASH).
Complication rates: infection, neurovascular injury, malpositioning of the
prosthesis, asceptic loosening of the prosthesis and dislocation.
Background summary
Total hip arthroplasty is a widely successful procedure, nevertheless their
survivorship has been limited by aseptic loosening and osteolysis secondary to
wear of the ultrahigh molecular weight polyethylene (UHMW-PE) in acetubular
components.
In response to the problem of UHMW-PE wear, highly cross-linked polyethylene
(HXLPE) for application in orthopaedic surgery was developed to reduce wear of
UHMW-PE. The wear resistance of HXLPE used in total joint arthroplasty has been
shown improve significantly with cross-linking. Cross-linking of PE is
achieved through the use of ionizing radiation. Ionizing radiation forms free
radicals in polyethylene. These free radicals recombine with each other and
form cross-links in the polymer. However, the free radicals generated during
irradiation become trapped and affect the long-term oxidative stability of the
material, causing embrittlement of the PE component .The most effective method
of stabilization is to melt the irradiated PE, which reduces the concentration
of the residual free radicals to undetectable levels.The method of irradiation
and melting improves the wear resistance and does not compromise the oxidation
resistance of PE. However, the post irradiation melting step reduces the
mechanical properties and fatigue strength of irradiated PE
A new generation of cross-linked PE has been developed by stabilizing PE by
addition of vitamin E, avoiding post irradiation melting. The major
physiological role of vitamin E is to react with free radicals and protect
against oxidative degradation. This would lead to double advantage of
preventing long-term oxidation and preserving mechanical properties.
Study objective
2.1 Primary objective
To compare the wear rate 24 months after THA of HXLPE stabilized with vitamin E
versus conventional UHMWPE for total joint arthroplasty.
2.2 Secondary objectives
1. To compare the wear rate at 3,12 and 24 months after THA between HXLPE
stabilized with vitamin E versus conventional UHMWPE.
2. To assess the effect of increased head size on wear rates in HXLPE
stabilized with vitamin E versus conventional UHMWPE.
3. To assess the effect of activity level (SQUASH activity scale) on wear rates
in HXLPE stabilized with vitamin E versus conventional UHMW polyethylene.
4. To assess the clinical performance (HHS score, WOMAC, SF-36, SQUASH)
preoperative and 3,12 and 24 months after THA between HXLPE stabilized with
vitamin E versus conventional UHMWPE.
5. To assess the rate of complications, revisions and mortality between HXLPE
stabilized with vitamin E versus conventional UHMW polyethylene.
Study design
Randomized controlled trial of 200 patients subjected to a total hip
arthroplasty. The first group involves a HXLPE stabilized with Vitamin E (RM
cementless monoblock pressfit Vitamys® cup, Mathys AG Bettlach). The second
group involves a conventional UHMW polyethylene (RM cementless monoblock
pressfit®, Mathys AG Bettlach). The PE wear will be monitored 3, 12 and 24
months after surgery. The function of the hip will be monitored at regular
interval just before surgery and 3, 12, 24 months after surgery.
Intervention
Total Hip Arthroplasty
Total Hip Arthroplasty will be performed using the RM cementless monoblock
pressfit cup (Mathys AG Bettlach) or the RM cementless monoblock pressfitt
Vitamys cup (Mathys AG Bettlach). Critical aspects of the surgical procedure
will be standardized.
RM Pressfit
RM cementless monoblock pressfit cup is a standard implant.
The implant is made of:
Structure: Elliptical design and a slight polar flattening
Polyethylene: UHMW- PE
Coating material: Pure titanium particles (TiCP)
RM pressfitt Vitamys
RM cementless monoblock pressfit cup stabilized with Vitamin E.
The Vitamys cup is a polyethylene from the same raw material as UHMWPE which
has been highly cross linked and additionally endowed with 0.1% of vitamin E,
an antioxidant also called tocopherol. The average content of Vitamin E in a
Vitamys cup is around 50 mg (max daily amount 400mg) The ingredients are
homogeneously mixed, sintered under pressure, and highly cross-linked by an
irradiation dose of 100kGy.
The implant is made of:
Structure: Elliptical design and a slight polar flattening
Polyethylene: UHMW- PE added with natural anti-oxidant, vitamin E.
Coating material: Pure titanium particles (TiCP)
RM cementless monoblock pressfit Vitamys cup is a CE marked implant and an
approved HXLPE for total hip replacements (according to ISO standards 5834-2).
Study burden and risks
Both treatments that patients can be allocated to are standard of care
treatments. Participants should not expect any personal benefits from their
participation in this study. Their participation may help other people with
primary or secondary arthritis of the hip in the future. All surgeons perform
THA as used in the two groups of this trial. As with any surgical procedure,
potential risks for THA surgery include the following:
- Infection
- Neurovascular injury (injury to the nerves or vessels)
- Death
During the entire study, 5 X-rays will be made as part of Standard Of Care.
There are no other known additional risks involved in this study, aside from
the inconvenience of completing a set of questionnaires, which will take
approximately 15 minutes at each visit. In total, each clinical FU visit will
take 25 minutes. Participants will be informed about any new information that
might affect their
willingness to continue to participate in this research
Bosboomstraat 1
3582 KE Utrecht
Nederland
Bosboomstraat 1
3582 KE Utrecht
Nederland
Listed location countries
Age
Inclusion criteria
All patients scheduled for a total hip arthroplasty. Inclusion criterion, patients diagnosed for coxarthrosis, dysplastic coxarthrosis, rheumatoid arthritis , necrosis of the head of the femur or posttraumatic coxarthrosis. Patients between 20 and 75 years old at the time of inclusion.
Exclusion criteria
Exclusion criteria; patients designated for revision surgery, suffer from sepsis, malignant tumours, severe diabetes mellitus, severe cardiovascular diseases (ASA>II)
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
In other registers
| Register | ID |
|---|---|
| Other | Aangemeld bij Nederlands Trialregister. Binnen 4 weken is NCT nummer bekend. |
| CCMO | NL31682.100.10 |
| OMON | NL-OMON23978 |