Infection and Inflammatory Reaction Clinical Trial
Official title:
Early Diagnosis of Pending Failures of Total Hip Arthroplasty With Hard to Hard Bearings
During last 6 years approximately 10.000 ceramic balls and 5.000 ceramic liners have been
implanted in the region Emilia-Romagna in Italy (4 million Every single year approximately
60.000 hip prostheses are implanted in Italy. Quality of life of patients after surgery is
very good, as widely demonstrated in the literature. On the basis of data produced by the
only complete hip register in Italy that is run in our Lab (RIPO, Register of Orthopedic
Implants in the Regione Emilia-Romagna) survival rate of primary total hip prosthesis is
95.6% at 9 years. Reasons for revision are mainly aseptic loosening of one or both
components (40% of the total) and dislocation (26%), being the latter much more frequent in
the first two years. Less frequently revision is due to sepsis (7% of the total),bone
fracture (11%), prosthesis fracture (3%) or pain (3%). Revision is relates, among the
others, to prosthesis-related factors, such as fixation to bone and articular coupling. In
our experience, during the last ten years 32% of implants had both articular component in
ceramic , 34% had metal head and plastic liner, 24% ceramic head and plastic liner, 10% both
components in metal.
Each solution has strengths and weakness and they have been identified and clinically
applied in order to overcome step by step limitations observed in the previous one. The most
recent are the hard-on-hard bearings, that is ceramic on ceramic and metal on metal. These
two solutions, beside very promising results on wear resistance, show some peculiar
failures: respectively fracture of the ceramic component and hypersensitivity induced by
metal ions.
Aim of research proposal is to investigate two uncommon and less investigated early symptoms
of failure:
- 'noising hip' in ceramic on ceramic total hip arthroplasty
- pain without radiographic signs of loosening in metal on metal total hip arthroplasty
These two situations are extremely relevant, as they prelude to a failure of the
prosthesis. If clearly identified they could represent a powerful tool in early
diagnosis of pending failure To reach this goal our patients wearing hard-on-hard total
hip arthroplasty, suffering for described symptoms will undergone a specific diagnostic
procedure.
The first group will be studied through CT scan of the patients to evaluate impingement or
instability of the prosthesis, and a needle aspiration for synovial fluid. The fluid will be
examined to identify ceramic wear debris, according to a method of separation and analysis
in scanning electron microscopy that was set in our Lab.
Sound will be recorded by means of a wearable sensor set capable of recording the articular
noise produced during level walking. This instrumentation will be coupled to motion analysis
technology.
This would make possible a diagnostic approach able to correlate the involved factors to
clinical occurrences, on the basis of the recorded frequencies.
-Second group will be studied through the dosage of circulating ions, deriving from the
articular surfaces and through the histological classification of vasculitis in periimplant
tissues. There is increasing evidence, indeed that locale release of submicron particles
worn out from articular surfaces can release metal ions (mainly Chromium and Cobalt)
responsible for lymphocyte local infiltration. In particular CD20 positive B lymphocyte and
CD3 positive T lymphocyte and sometimes CD68 positive plasma cells are present. The cells
could justify the development of pseudotumors in metal-on metal hip prosthesis.
Data collected from patients matched to in vitro results will allow us to to avoid or at
least propose a more appropriate timing for revision surgery.
Every single year approximately 60.000 hip prostheses are implanted in Italy. Quality of
life of patients after surgery is very good, as widely demonstrated in clinical experience
and in the literature. On the basis of data produced by the only complete hip register in
Italy, that is run in our Lab (RIPO, Register of Orthopedic Implants in the Regione
Emilia-Romagna https://ripo.cineca.it) survival rate of primary total hip prosthesis is
95.6% at 9 years. Reasons for revision are mainly aseptic loosening of one or both
components (40% of the total) and dislocation (26%), being the latter much more frequent in
the first two years. Less frequently revision is due to sepsis (7% of the total),bone
fracture (11%), prosthesis fracture (3%) or pain (3%).
Revision can be related, among the others, to prosthesis-linked factors, such as fixation to
bone and articular coupling.
In the experience of RIPO, during the last ten years 32% of implants had both articular
component in ceramic, 34% had metal head and plastic liner, 24% ceramic head and plastic
liner, 10% both components in metal.
Each solution has strengths and weakness and they have been identified and clinically
applied in order to overcome step by step limitations observed in the previous one.
Alumina ceramic-on-ceramic (COC) bearings have been shown to produce substantially less wear
debris than traditional metal/ceramic on polyethylene bearings. In addition, the alumina
ceramic material itself is essentially bioinert in both bulk and particulate form . Unlike
metal-on-metal bearings (MOM), this bearing couple does not release metal ions into the body
either from the articulation or from breakdown of wear debris. Weakness of
ceramic-on-ceramic bearings are represented by brittleness of the material. Ceramic can
fracture, even in very few cases, due to trauma or to malpositioning. Beside this occurrence
of noise during gait of patients can be extremely disturbing for patient itself, leading to
request of revision. These two solutions represent more recent proposal that technology
suggested to overcome problem of wear.
Hard components on plastic has the unsolved problem of wear debris, leading to osteolysis
and consequent failure of he im plant. The problem has only partially solved by the
introduction of cross linked polyethylene, aimed to improve tribological behaviour of the
plastic.
Istituto Rizzoli is the only public monospecialistic research hospital in Italy. Nearly 500
hip prosthesis revisions are performed here every year in the structure. Due to its high
specialization difficult cases from all the country are treated here, not on ly when anatomy
of the patient is damaged (dislocation of the hip, post traumatic arthritis) but .even more
frequently when failure of the implant occurred.
Aim of research proposal is to investigate two uncommon and less investigated early symptoms
of failure:
- 'noising hip' in ceramic on ceramic total hip arthroplasty
- pain in metal on metal total hip arthroplasty Even if not numerically so important,
these two situations are extremely relevant, as they prelude to a failure of the
prosthesis. If clearly identified they could represent a powerful tool in early
diagnosis of pending failure.
The first point will be studied through CT scan of the patients to evaluate impingement or
instability of the prosthesis, and a needle aspiration for synovial fluid. The fluid will be
examined to identify ceramic wear debris, according to a method of separation and analysis
in scanning electron microscopy that was set in our Lab.
Sound will be recorded by means of a wearable sensor set capable of recording the articular
noise produced during level walking. This instrumentation will be coupled to motion analysis
technology, so as to provide a temporal correlation between the recorded noise and the gait
cycle. It will be developed in the first phase of the project. In parallel surface analyses
will be conducted on retrievals that are stored in the Lab since 2000, in one of the biggest
retrieval study ever conducted in our country. Type of damage, surface roughness of both
ceramic components will be analysed and compared to clinical data.
Finally the study will be completed in vitro, using an hip simulator, to reproduce the
possible clinical scenarios leading to hip noise, record, and analyse it in a reproducible
and robust manner. This would make possible a diagnostic approach able to correlate the
involved factors to clinical occurrences, on the basis of the recorded frequencies. Second
point will be studied through the dosage of circulating ions, deriving from the articular
surfaces and through the histological classification of vasculitis in periimplant tissues.
There is increasing evidence, indeed that locale release of submicron particles worn out
from articular surfaces can release metal ions (mainly Chromium and Cobalt) responsible for
lymphocyte local infiltration. In particular cluster of differentiation antigen 20 (CD20)
positive B lymphocyte and cluster of differentiation 3 (CD3) positive T lymphocyte and
sometimes cluster of differentiation antigen 68 (CD68) positive plasma cells are present.
The cells could indicate a specific phlogistic condition responsible for pain and eventually
subsequent revision.
Data collected on studied population will allow a better understanding of the two phenomena
and possibly will suggest new therapeutic approaches to the problems.
;
Observational Model: Cohort, Time Perspective: Prospective
| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Completed |
NCT02177097 -
Chronic Pain, Inflammation and Infection After Joint Replacement
|
N/A |