The APEX Knee System is designed to provide surgeons with a concise and logical set of options to accurately restore joint mechanics, improve stability and maximize range of motion of the knee. At OMNIlife science we believe that you are uniquely you. For this reason, the APEX Knee replacement was designed from the ground up based on extensive clinical anthropomorphic analysis of male and female anatomy. As a result, the Apex knee is offered in a wide range of primary sizes as well as specifically designed and proportioned intermediate sizes with design characteristics that allow the surgeon to specifically match your unique anatomic requirements whether you are male or female.
In addition to asymmetric component design, additional “plus” sizes are available in size 2+ and 3 + femoral components. These unique femoral components allow the use of standard size 3 and 4 box cuts. Thus, without re-cutting the femur, the surgeon has the option to intra-operatively change femoral component sizes to a plus size component with a thinner anterior flange and larger A/P to M/L size ratio to address potential differences in male and female anatomy.
The Apex Knee femoral component has been designed with high flex geometry. Generously proportioned posterior femoral condyles maintain low contact stress even when the knee is in deep flexion.
The asymmetry (separate left and right configurations) of both the femoral and tibial components is the result of a highly detailed intra-operative anthropomorphic study of 125 patients. Matching the left and right implant geometry to patient anatomy provides the best possible component fit and stability.
Tibial inserts are provided in crutiate retaining ("Congruent") and cruciate substituting ("Ultra") configurations. Congruent inserts are offered in several different thicknesses to permit precise soft tissue balancing.
Ultra inserts have a deep dish configuration to provide maximum conformity and stability through deep flexion without the need for bone sacrificing post and cam mechanisms associated with other posterior stabilized designs.
The Apex Knee system has been designed to precisely match the size of the tibial insert to the femoral components. Matching the tibial insert and femoral component optimizes contact areas, resulting in contact stresses lower than 15MPa in extension.*
The femoral component has been designed with a deep, wide patella groove set at a 6° Q angle. The patella groove is designed to mate with a spherical dome patella component. The design of the Apex Knee femoral component’s patella groove permits excellent tracking of the patella throughout the full range of motion.
The Apex Knee femoral component has a generously curved sagittal geometry that eliminates edge loading during varus/valgus liftoff. A 5 degree liftoff is depicted.
Apex Knee Inserts have been designed to permit easy instrument-free front loading insertion onto the tibial tray. A proprietary double dovetail rail and groove capture system has been designed and extensively tested to minimize micro motion and backside wear potential. An additional fixation bolt further assures the stability of the tibial insert on the tibial tray.
The Apex Knee tibial component system permits the use of tibial inserts one size higher or any size lower than the tibial tray size. This allows the tibial tray with the best possible coverage of the tibial plateau to be used with an insert that matches the femoral component. In all cases, the numerical size of the tibial insert should match that of the femoral component, including the “plus” sizes. For example, a size 2 tibial insert should be used with a size 2+ femoral component.
The Apex Knee tibial tray has been designed with a 4º posterior slope. The tray incorporates a tapered post located 60% A/P. The post has two posteriorly swept keels. Both the length of the tapered post and the dimensions of the keel proportionally increase in size as tray size increases. This keel configuration maximizes stability while avoiding impingement of the anterior cortex of the tibia.
The Apex Knee System offers both porous coated uncemented and cemented versions of its tibial and femoral components.
Apex Knee System porous coated femoral components employ OMNI's proprietary OMNIgrip CoCr porous coating. OMNIgrip CoCr. consists of a a unique dual layer of particles: an inner layer of sintered spherical beads covered with an irregularly shaped surface geometry. This BioPhasic™ surface has an excellent porosity for both osseointegration and initial stability.
The Apex Knee porous coated tibial tray components employ OMNI's proprietary OMNIgrip Ti-HA porous coating. OMNIgrip Ti-HA consists of a layer of OMNI's titanium plasma spray coating with an additional layer of hydroxyapetite to provide the best possible conditions for bony ingrowth.
The APEX knee porous coated tibial components available with and without screw holes. Cancellous bone screws can be angled up to 10 degrees.
* Internal test report, OMNIlife science, Inc.