Patient Specific Anatomical Reconstruction
Modular stems and necks enable independent adjustments of leg length, offset, and version.
The OMNI MOD™ hip system is designed to provide surgeons with a concise and logical set of options to accurately restore joint mechanics, leg length discrepancy, and soft tissue balance. This system combines clinically proven design features that are important for long-term performance with several new and innovative options by using modular stems, necks, and heads.
The ability to independently choose stem size, neck offset, version angles, and head size allows surgeons to more precisely match the specific anatomical needs of their patients. Ninety-six head and neck combinations are available to achieve accurate leg length and soft tissue balance.*
Worry-free Modular Junction
Patented Dual Press™ modular junction creates a strong, reliable joint.
Dual Press technology press fits the neck into the stem without any gap in between. The mating peg on the neck seats into the proximal end of the stem and is pressed together using a simple instrumentation. Two bands of interference fit create the "Dual Press" : a mechanical lock at both proximal and distal ends of the mating peg.
The process of mating the neck and stem can be performed in situ, accommodating the use of any surgical technique. The design eliminates the need for tapers, which can be difficult to manufacture and prone to dissociation. For all practical purposes, the system will perform as a one-piece stem (with a conventional modular head) after attachment of the neck.
Modular Neck Versatility
Neck selection independent of stem size allows customized results
Most contemporary THA femoral components offer one or two neck offsets for each distal stem diameter. This limits final head position to adjustments in neck length via the modular head. Often this dilemma requires compromises between leg length and stability.
The modular necks are designed to provide a wide range of final stem geometries. All necks and stems employ a universal modular junction, allowing any neck to be used with any stem. Extensive mechanical testing has proven the strength of this design.*
The proximal end of each stem includes an alignment pin that engages with the mating hole on the distal surface of each neck. Neutral necks have a single hole; anteversion necks have two holes for +/- 13°.
Top to Bottom Stability
Stem geometry securely engages healthy bone
The "Keyhole" proximal shape of the Modular Stem is intended to provide a good anatomical fit and inherent stability. The circumferential CP-Ti plasma spray porous coating is applied on the stepped proximal surface for improved resistance to subsidence.
Mid-stem flutes are provided for torsional stability. They do not, however, extend to the distal tip to avoid early engagement and improper alignment.
The distal stem will have either a single slot (a "clothespin" slot") in the smaller sizes or a unique "V"-slot™ in the large sizes. This produces a nearly constant normalized stiffness as a function of stem size, which is a unique concept to the Modular Stem.
* Data on file with OMNIlife science, inc.