The Biolign® STACC ACIF System is indicated for use as an intervertebral body fusion device in skeletally mature patients with degenerative disc disease at one level from C3-C7. Cervical disc disease is defined as discogenic pain with degeneration of the disc confirmed by history and radiographic studies. Patients should have six (6) weeks of non-operative treatment. The Biolign® STACC ACIF System is to be used with autograft bone graft and is implanted via an open anterior approach. The Biolign STACC ACIF system is intended to be used as a stand-alone system using the bone screws provided for fixation. It may also be used with supplemental fixation system that have been cleared for use in the cervical spine, such as cervical plating systems.
As the preferred design to ensure fixation in cancellous vertebral bone, cancellous screws—combined with a unique screw head design create a "lag" effect between the vertebral body and the implant.
This "lag" effect provides constant compressive forces against the implant which results in a greater interface between the graft and the endplate to facilitate the fusion process
STACC screws are angled and designed to direct axial forces along the long axis of the screws, significantly reducing bending movents and preventing de-rotation of the screw and / or screw back- out.