The InFix device is manufactured from implantable grade
Ti-6Al-4V alloy that conforms to ASTM F-136. The device is comprised
of two opposing Endplates (provided in 0°, 3°, 6° and 9° angles)
supported by vertical members or “Struts” available in a range of
heights, allowing the surgeon to fix the vertebrae in proper
anatomical alignment and lordosis. Each of the Struts includes a
loadsharing mechanism that allows a limited amount of strain across
the fusion mass while supporting the load bearing surfaces. An Ultra
High Molecular Weight Polyethylene (UHMWPE) Endcap may be placed
inside the device prior to packing it with bone graft. The Endcap
effectively blocks the posterior opening in the device to contain the
material inside. Holes in the Endplates provide space for bone
in-growth while angled spikes penetrate the vertebral endplates and
provide resistance to rotation and migration.
The InFix device is designed for direct placement between two
vertebral bodies. Component sizes and dimensions are shown below. All
dimensions are in millimeters. Strut heights are in 2mm increments.
The InFix device is assembled and locked in-situ; bone graft
is then inserted within the device and up to the anterior rim of the
The InFix device is implanted using a set of specialized
The InFix Device is a vertebral body replacement device
intended for use in the thoracic and/or thoracolumbar spine (T3-L5) to
replace a collapsed, damaged or unstable vertebral body resected or
excised (i.e., partial or total vertebrectomy procedures) due to tumor
or trauma (i.e., fracture). The InFix System is designed to
restore the biomechanical integrity of the anterior, middle and
posterior spinal column even in the absence of fusion for a prolonged
period. The InFix Device is intended to be used with bone graft.
Following are specific warnings, precautions, and adverse effects,
which should be understood by the surgeon and explained to the
patients. These warnings do not include all adverse effects, which can
occur with surgery in general, but are important considerations
particular to metallic internal fixation devices. General surgical
risks should be explained to the patient prior to surgery.
- THE SAFETY AND EFFECTIVENESS OF INTERBODY FUSION HAS BEEN
ESTABLISHED ONLY FOR SPINAL CONDITIONS WITH SIGNIFICANT MECHANICAL
INSTABILITY OR DEFORMITY REQUIRING FUSION WITH INSTRUMENTATION.
These conditions are significant mechanical instability secondary to
degenerative spondylolisthesis with objective evidence of neurologic
impairment, fracture, dislocation, scoliosis, kyphosis, spinal tumor
and failed previous fusion (pseudarthrosis). The safety and
effectiveness of these devices for any other conditions is unknown.
(APPLICABLE ONLY TO INDICATIONS OUTSIDE THE UNITED STATES)
- Potential risks identified with the use of this device system,
which may require additional surgery, include:
- Device component
- Loss of fixation.
- Fracture of the vertebra.
- Neurological injury.
- Vascular or visceral injury.
SELECTION OF THE IMPLANT IS EXTREMELY IMPORTANT. The potential for
satisfactory fixation is increased by the selection of the proper
size, shape and design of the implant. While proper selection can
help minimize risks, the size and shape of human bones present
limitations on the size, shape, and strength of implants. Implants
height should be determined such that adequate decompression and
stability are imparted to the instrumented segment.
NEED FOR SUPPLEMENTAL FIXATION MUST BE DETERMINED BY THE SURGEON
BASED UPON THE AMOUNT OF INSTABILITY IMPARTED BY THE SURGERY, AS
WELL AS THE PATHOLOGY ITSELF. (APPLICABLE ONLY TO INDICATIONS
OUTSIDE THE UNITED STATES)
- IMPLANTS CAN BREAK WHEN
SUBJECTED TO THE INCREASED LOADING ASSOCIATED WITH DELAYED UNION OR
NON-UNION. Internal fixation appliances are load sharing devices
which are used to obtain an alignment until normal healing occurs.
If healing is delayed or does not occur, the implant may eventually
break due to fatigue. The degree or success of union, loads produced
by weight bearing, and activity levels will, among other conditions,
dictate the longevity of the implant. Notches, scratches or bending
of the implant during the course of surgery may also contribute to
early failure. Patients should be fully informed of the risks of
- PATIENT SELECTION. In selecting patients
for internal fixation devices, the following factors can be of
extreme importance to the eventual success of the procedure:
- The patient’s weight. An
overweight or obese patient can produce loads on the device that
can lead to a loss of interbody height or failure of the device
and/or the operation.
- The patient’s occupation or
activity. If the patient is involved in an occupation or
activity that includes substantial walking, running, lifting or
muscle strain, the resultant forces can cause loss of disc
height and/or failure of the device.
- A condition of
senility, mental illness, alcoholism, or drug abuse. These
conditions, among others, may cause the patient to ignore
certain necessary limitations and precautions in the use of the
appliance, leading to implant failure or other
- Certain degenerative diseases. In some
cases, the progression of degenerative disease may be so
advanced at the time of implantation that it may substantially
decrease the expected useful life of the appliance. For such
cases, orthopaedic devices can only be considered a delaying
technique or temporary relief.
- Foreign body
sensitivity. Where material sensitivity is suspected,
appropriate tests should be made prior to material selection or
- Smoking. Patients who smoke have been
observed to experience higher rates of pseudarthrosis following
surgical procedures where bone graft is used.
- These warnings do not include all adverse effects that can occur
with surgery in general. General surgical risks should be explained
to the patients prior to surgery.