Authors' objectives:

The objective of this Assessment is to determine whether AIDA improves health outcomes when used as an alternative to anterior-plated ACDF for patients with DDD of the cervical spine.

Authors' recommendations: After 2 years' follow-up, trials of the Prestige ST and ProDisc-C discs found noninferiority as measured by the NDI and overall success composite outcome. Although informative, the evidence is not sufficient to allow concluding whether AIDA with either device is as beneficial as ACDF because of uncertainty regarding longer-term outcomes. Experience with ACDF and its high success rate requires a convincing rationale and supporting evidence to utilize a different procedure—noninferiority alone is insufficient. Neither trial provides adequate direct evidence over a relevant follow-up period (suggested to be 5 to 7 years) on subsequent adjacent-level DDD in control and investigational group patients. Based on the available evidence, the Blue Cross and Blue Shield Association Medical Advisory Panel made the following judgments about whether artificial intervertebral disc arthroplasty as a treatment for DDD of the cervical spine meets the Blue Cross and Blue Shield Association Technology Evaluation Center (TEC) criteria. 1. The technology must have final approval from the appropriate governmental regulatory bodies. The Prestige ST and ProDisc-C Cervical discs received U.S. Food and Drug Administration (FDA) marketing approval in July and December 2007, respectively. The discs are indicated in skeletally mature patients for C3-C7 disc reconstruction following single-level discectomy for intractable radiculopathy and/or myelopathy. The devices are implanted via an open anterior approach. Intractable radiculopathy and/or myelopathy should present with at least one of the following items producing symptomatic nerve root and/or spinal cord compression that is documented by patient history (e.g., pain [neck and/or arm pain], functional deficit, and/or neurological deficit), and radiographic studies (e.g., CT, MRI, X-rays, etc.): 1) herniated disc, and/or 2) osteophyte formation. A third product (Bryan Cervical Disc) received an approvable decision by an FDA advisory panel July 17, 2007, but had not received final marketing approval at the time this Assessment was originally prepared. As this Assessment was in press, the Bryan disc received PMA approval from the FDA (May 12, 2009). The Bryan disc is intended for use in patients similar to those for whom the Prestige device is indicated. As this Assessment excluded studies using any non-FDA-approved or precursor devices, evidence on the Bryan disc was not included in the original body of the Assessment; data on this device are included in Appendix C of this Assessment. The addition of these data does not change the conclusions of this Assessment. 2. The scientific evidence must permit conclusions concerning the effect of the technology on health outcomes. Evidence derives from two randomized controlled trials designed to test noninferiority—one of the Prestige ST and the other of the ProDisc-C. The Prestige ST trial compared AIDA (n=276) with anterior plated ACDF using allograft bone (n=265); the ProDisc-C trial compared AIDA (n=103) with ACDF (n=106). The evidence is insufficient to support conclusions concerning the comparative effect of AIDA on health outcomes. First, the evidence does not permit conclusions on the long-term performance of AIDA and adverse events. Device performance, durability, and revisability are key considerations for the relatively young population enrolled in these trials. The available evidence also is insufficient to permit conclusions as to whether or not AIDA affects the postsurgical development of adjacent-level DDD. In contrast, conclusions on the relative safety of cervical disc arthroplasty appear sufficiently supported in the short term. Second, trial results demonstrated noninferiority for AIDA versus ACDF for the primary and overall success composite outcome. In the Prestige ST trial, while superiority with respect to the neurological status was found, and thus for the composite including it, quantitative data on neurological status are not available and it is not known whether it was obtained by blinded examiners, precluding interpreting its clinical meaning and relevance. Further, the Prestige ST trial did not find better outcomes of AIDA in terms of the NDI, a clinically validated, multidimensional outcome measure of neck pain and disability caused by cervical DDD. Taken together, these uncertainties preclude determining the comparative effect of AIDA on health outcomes. 3. The technology must improve the net health outcome; and 4. The technology must be as beneficial as any established alternatives. The evidence does not permit conclusions as to whether AIDA for the cervical spine improves net health outcomes or is as beneficial as established alternatives. 5. The improvement must be attainable outside the investigational settings. Whether artificial disc arthroplasty for the cervical spine improves the net health outcome has not been established in the investigational setting. Based on the above, artificial intervertebral disc arthroplasty for the treatment of patients with cervical degenerative disc disease does not meet the TEC criteria.

Project Status: Completed

URL for project: http://www.bcbs.com/blueresources/tec/vols/24/artificial-intervertebral.html

Year Published: 2009

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: BlueCross BlueShield Association

Contact Address: BlueCross BlueShield Association, Technology Evaluation Center, 225 North Michigan Ave, Chicago, Illinois, USA. Tel: 888 832 4321

Contact Name: tec@bcbsa.com

Contact Email: tec@bcbsa.com

Copyright: BlueCross BlueShield Association (BCBS)