Newswise — Currently, many patients in the United States who suffer from neck and arm pain due to herniated cervical discs are treated surgically with removal of the disc, followed by fusion. Spinal fusion is an operation in which bone is grafted onto the spine, creating a solid union between two or more vertebrae. Instrumentation such as metal plates and screws may be used to enhance the fusion and provide additional support. The solid union created between the vertebrae stops the movement between the bones. While this treatment is effective in helping to reduce pain from motion and nerve root inflammation, the limited mobility of the neck may lead to the herniation of other discs over time.

In order to maintain normal neck motion, several artificial cervical discs have been developed and have been used outside the United States over the past decade. One of these artificial discs, the PRESTIGE ST artificial cervical disc (Medtronic Sofamor Danek, Memphis, Tenn.), underwent an FDA-approved multicenter clinical trial in the United States, concluding in 2005.

Four centers that participated in the clinical trial are included in this study, Cervical Disc Arthroplasty with the Prestige ST Device: One and Two Year Results from a Multi-Center Randomized Controlled Trial, which will be presented by Praveen V. Mummaneni, MD, 3:00 to 3:15 p.m. on Monday, April 24, 2006, during the 74th Annual Meeting of the American Association of Neurological Surgeons in San Francisco. Co-authors are Regis W. Haid, MD, Wade Ceola MD, Joseph Stachniak, MD, and Paul Sawin, MD.

A total of 120 patients participated in the clinical trials at the four medical centers. Entrance criteria included single-level (C3-7) disc disease with concordant radiculopathy. Demographics of the treatment groups were similar. The discs most frequently operated on were at C5-C6 and C6-C7 levels. Fifty-four patients received the standard treatment of cervical discectomy and fusion. Sixty-six patients received cervical discectomy followed by implantation of the PRESTIGE ST artificial cervical disc.

Patient outcome was evaluated utilizing neck and arm visual analog scales (VAS), neck disability index (NDI), and Short Form-36 (SF-36) questionnaires preoperatively, and at each postoperative interval, for up to two years. Dynamic x-rays were obtained at all intervals, and segmental motion at the operated levels was quantified.

Preliminary results show that the patients who received the PRESTIGE ST artificial cervical disc and those who received a fusion fared equally well in their outcomes, yet patients with the PRESTIGE ST artificial cervical disc had greater maintenance of their neck motion than did the patients with a fusion. In most instances, the differences were statistically significant. Radiographic analysis shows the Prestige device to maintain/restore segmental motion. No revision surgeries were performed in the Prestige group, and two revisions occurred in the fusion group.

"In conclusion, early results from the clinical trial are encouraging and indicate that the PRESTIGE ST artificial cervical disc may become a viable alternative to cervical fusion in the near future," stated Dr. Mummaneni.

Founded in 1931 as the Harvey Cushing Society, the American Association of Neurological Surgeons (AANS) is a scientific and educational association with more than 6,800 members worldwide. The AANS is dedicated to advancing the specialty of neurological surgery in order to provide the highest quality of neurosurgical care to the public. All active members of the AANS are certified by the American Board of Neurological Surgery, the Royal College of Physicians and Surgeons (Neurosurgery) of Canada or the Mexican Council of Neurological Surgery, AC. Neurological surgery is the medical specialty concerned with the prevention, diagnosis, treatment and rehabilitation of disorders that affect the entire nervous system, including the spinal column, spinal cord, brain and peripheral nerves.