Charité disc.

A surgical approach commonly used in combating degenerative knee and hip conditions is now being utilized to successfully treat degenerative disc disease in the spine. Spine surgeons at the University of Pittsburgh are using the Charité™ Artificial Disc to completely replace damaged or worn out spinal discs with a high-tech substitute.

The Charite artificial disc consists of two cobalt chromium alloy endplates sandwiched around a movable high-density plastic core. The design of the disc helps align the spine and preserve its natural ability to move. Extensive clinical tests have shown that the Charite disk allows the patient a full return to flexibility and range of motion.

Lumbar degenerative disc disease, DDD, is a common disorder affecting 10 to 12 million persons. It occurs when spinal discs deteriorate—losing moisture, height and integrity of the tissues—as a result of injury, daily stress or natural aging. This deterioration causes vertebrae to rub against each other, possibly damaging nerve tissues, resulting in pain or numbness.

Until now, spinal fusion has been the traditional treatment for DDD. This treatment removes the diseased tissue and “fuses” the motion segments, thereby eliminating the pain source. However, due to the loss of motion in the operative levels of the spine, fusion can cause stress and increased motion in adjacent levels, possibly leading to degeneration in these levels.

With the Charite artificial disc procedure, since the damaged disc is removed and replaced with a similarly functioning artificial one, full flexibility and motion is restored and the natural integrity and design of the spine is maintained. Recovery time is significantly quicker as well.

The Charite artificial disc is attached to the vertebral bodies by six fixation teeth on each of the endplates. The teeth achieve fixation and stability without compromising the vertebral body. This mechanism of attachment provides both short and long-term stability and allows for intraoperative repositioning if necessary.

The convex sliding core interacting with the concave side of the endplates allows for the natural translation of motion of the operative segment. This design reduces the shear stresses at the implant/bone surface.

Charite is the first artificial disc approved by the Federal Drug Administration to treat patients with single-level DDD at levels L4 to S1. Results from a two-year clinical study of 375 patients show those patients implanted with the Charite disc improved or maintained their range of motion and experienced less pain compared with spinal fusion patients.

The Charite artificial disc was developed in Germany by orthopedic surgeons Kurt Schellnack and Karin Buttner-Janz. With thousands of implantations since 1987, it has the longest clinical experience of any artificial disc.