Stryker Triathlon Knee System, Хирургический протокол

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Warnings and Precautions
Indications
General Total Knee Arthroplasty (TKR) Indications
include:
• Painful, disabling joint disease of the knee resulting
from: non-inflammatory degenerative joint disease
(including osteoarthritis, traumatic arthritis or
avascular necrosis) or rheumatoid arthritis.
• Post-traumatic loss of knee joint configuration and
function.
• Moderate varus, valgus, or flexion deformity in which
the ligamentous structures can be returned to
adequate function and stability.
• Revision of previous unsuccessful knee replacement or
other procedure.
• Fracture of the distal femur and/or proximal tibia that
cannot be stabilized by standard fracture management
techniques.
Contraindications
• Any active or suspected latent infection in or about the
knee joint.
• Distant foci of infection which may cause
hematogenous spread to the implant site.
• Any mental or neuromuscular disorder which would
create an unacceptable risk of prosthesis instability,
prosthesis fixation failure, or complications in
postoperative care.
• Bone stock compromised by disease, infection or prior
implantation which cannot provide adequate support
and/or fixation to the prosthesis.
• Skeletal immaturity.
• Severe instability of the knee joint secondary to the
absence of collateral ligament integrity and function.
• Obesity. An overweight or obese patient can produce
loads on the prosthesis which can lead to failure of the
fixation of the device or to failure of the device itself.
See package insert for warnings, precautions, adverse
effects and other essential product information.
Adverse Effects
• While the expected life of total knee replacement
components is difficult to estimate, it is finite. These
components are made of foreign materials which are
placed within the body for the potential restoration of
mobility or reduction of pain. However, due to the
many biological, mechanical and physicochemical
factors which affect these devices but cannot be
evaluated in vivo, the components cannot be expected
to indefinitely withstand the activity level and loads of
normal healthy bone. Surgeons should counsel
patients against having unrealistic expectations about
the lifetime ofthe device.
• Dislocation of the femoral, tibial, or patellar prosthesis
can occur due to inappropriate patient activity,trauma
or other biomechanical considerations.
• Loosening of total knee components can occur. Early
mechanical loosening may result from inadequate
initial fixation, latent infection, premature loading of
the prosthesis, component malalignment or trauma.
Late loosening may result from trauma, infection,
biological complications including osteolysis, or
mechanical problems, with the subsequent possibility
of bone erosion and/or pain.
• Fatigue fracture of total knee components, including
tibial, femoral and patellar components, has occurred
in a small percentage of cases. Knee component
fracture may result due to inadequate support of the
component by the underlying bone or poor
component fixation.
• Peripheral neuropathies, nerve damage, circulatory
compromise and heterotopic bone formation may
occur.
• Serious complications may be associated with any
total joint replacement surgery. These complications
include, but are not limited to: genitourinary
disorders; gastrointestinal disorders; vascular
disorders, including thrombus; bronchopulmonary
disorders, including emboli; myocardial infarction or
death.
• Wear of polyethylene components has occurred and
literature reports have associated its occurrence with
bone resorption, loosening and infection.
• Metal sensitivity reactions have been reported
following joint replacement.
• Adverse effects may necessitate reoperation, revision,
arthrodesis of the involved joint, and/or amputation
of the limb.
• Soft tissue imbalance and/or laxity has been related to
component malalignment, which may result in early
wear and/or failure of the implant.
• With all implant devices, asymptomatic, localized
progressive bone resorption (osteolysis) may occur
around the prosthetic components as a consequence
of foreign-body reaction to the particulate matter of
cement, metal, ultra-high molecular weight
polyethylene (UHMWPE) and/or ceramic. Particulate
is generated by interaction between components, as
well as between components and bone, primarily
through wear mechanisms of adhesion, abrasion and
fatigue. Secondarily, particulate can also be generated
by third-body wear. Osteolysis can lead to future
complications, including loosening, necessitating the
removal and replacement of prosthetic components.
• It is known that very small particles from metal and
polyethylene components can be shed from the
component during normal use and over time.
Although most of this debris stays in the relevant
joint (e.g. contained in the synovium) or is trapped
by surrounding scar tissue, microscopic particles can
possibly travel or migrate outside of the joint to
different parts of the body. Currently, there are
unanswered questions about debris and microscopic
particles that can be generated from these
components. It has been shown that microscopic
debris particles can be disseminated (migrate)
throughout the body and on occasion have been
described as accumulating in lymph nodes and other
parts of the body. Although to date no significant
medical complications have been reported as a result
of these particles, their migration and/or
accumulation in the body have been described in the
literature. Given the insufficient time period during
which patients with these devices have been followed
and the fact that these devices are currently being
used in younger patients and remain in the body for
increasingly longer periods of time, it should be said
that the long-term effects, if any, from these particles,
is unknown. The long-term effects that have been
theorized include:
– Cancer: There is presently no scientific evidence
that links metallic or polyethylene debris with
cancer. However, the possibility cannot be ruled out.
– Lymphadenopathy and Accumulation in Other
Tissues/Organs: There have been a few reports of
the accumulation of wear debris in lymph nodes
(proximate and distal). Although no medical
complications or disease process has been reported
as stemming from these accumulations, their
existence should be recognized to facilitate
diagnosis and avoid confusion with suspicious
lesions, cancerous or otherwise.
– Systemic Disease: There has been some speculation
that there could be an association between
migration of debris and as yet unspecified systemic
effects. No case studies or other reports have been
published suggesting any such possibility. Again,
given the limited time period during which patients
receiving these implants have been followed, it
cannot be scientifically proven that some long-term
effect may not show up in the future. Given the
dearth of scientific data suggesting any association
is by the use of these materials for several decades, it
is strongly believed that the benefits of these devices
clearly outweigh the potential risks for any such
theoretical long-term effect.
Patient Counseling
Surgeons should discuss all relevant contraindications,
adverse effects and the need for post-implantation
protection with their patients.
Triathlon Knee System
Surgical Protocol