The Prosthesis

 

FREEDOM LUMBAR DISC - by Axiomed Spine Corporation

The Freedom Lumbar Disc is a new viscoelastic artificial disc intended to replace a symptomatic lumbar degenerative disc. The Freedom Lumbar Disc consists of:
 

  • Two end caps that engage the retaining plates through apertures.
  • Two titanium alloy retaining plates.
  • An elastomeric core bonded to the retaining plates (AxioLock (TM)).

 

 

The device is offered in multiple wedge angles, sizes, and heights. The implant design accommodates spinal levels L3/L4 through L5/S1 and is designed to withstand the forces and wear characterized by decades of use as an implant in relatively young patients.

 

Artificial Discs

The ideal prosthetic disc will simultaneously support load, absorb shock, and facilitate three dimensional motion. First generation discs, modeled on ball-and-socket designs, do not meet this standard.

Biomechanical testing has shown the Freedom Lumbar Disc meets this standard. Through its unique design and materials, the Freedom Lumbar Disc strives to match the performance characteristics of the natural disc, providing:
 

  • Dampening (shock absorption) and load carrying capacity
  • Passive restraint to the forces experienced during normal daily activities
  • Flexibility and motion to the spinal segment
  • Biostability, demonstrated through ISO 10993 testing
  • Long fatigue life: 50 million cycles in axial compression and 30 million cycles in coupled motion fatigue (wear) testing

 

The Freedom Lumbar Disc has successfully completed extensive biomechanical and biocompatibility testing, and also a complete manufacturing process validation. Based on this compendium of data, AxioMed has received Investigational Device Exemption (IDE) from the U.S. Food & Drug Administration.

 

 

The PRODISC®-L-intervertebral disc prosthesis consists of two cobalt-chrome-molybdenum-plates, a proven metal alloy with high body-compatibility, which are covered with a titanium layer thus enabling the bone to grow into the prosthesis.

 

 

 

A plastic (polyethylene) core between the plates secures flexibility within the affected vertebral motion segment (ball-socket-principle).Any overstress of the adjacent intervertebral discs, such as may occur after a spinal fusion, can thus be avoided.

 

The individual elements are available in differing sizes, so that the surgeon is able to customize the device to each patient's unique anatomic and physiological requirements.

 

Fixing of the Prosthesis

 

In order to achieve a short-term primary stability directly following surgery, the PRODISC®-L-intervertebral disc is attached to the vertebra by means of a keel and two “spikes”. The necessary stability is thus secured from the very beginning.

 

In addition, the whole surface is covered with a patented highly porous layer of pure titanium.

This extremely rough and porous surface enables the ingrowth of bones into the metal components.