Zigler's role as Principal Investigator for the ProDisc, Synthes Spine's artificial disc replacement system, was to monitor all the clinical ProDisc cases done at the Texas Back Institute, and also to serve as a resource to Synthes on questions about cases done at all of the 19 other investigative sites. On August 14, 2006, the ProDisc-L Total Disc Replacement was approved by the FDA for use as a treatment for functionally disabling pain from lumbar degenerative disc disease. It was the second device to be approved by the FDA for such a purpose. As a condition of approval, Synthes Spine is required to conduct a five-year study assessing the long-term safety and effectiveness of the disc. The study will include the 286 patients who participated in the pre-approval clinical trials. The company is also required to complete an annual analysis and report any major adverse events. These conditions are similar to those imposed on the Charite artificial disc. Zigler is himself responsible for publication of the national data now that the ProDisc-L has been FDA-approved. More recently, questions about ethics of surgeon investigators in the Pro Disc study have been raised, specifically in a New York Times article about conflicts of interest related to his Zigler's financial ties, in which it is reported that he invested $25,000 in the company. Since the time of these articles, there has been no substantiation to support the New York Times' allegations, and a follow-up FDA audit of Zigler's ProDisc site prompted by these allegations turned up no evidence of any wrongdoing.
In the media
Zigler has appeared as a guest expert on Orange CountyNews network in Orange County, California, as well as Good Morning Texas, a morning show produced by the ABC affiliate WFAA-TV in Dallas, Texas. He has been consulted numerous times regarding the spinal injuries of such high-profile celebrities as Christopher Reeve and Jason Priestley. Zigler has also been a subject in a New York Times article that raises questions about the ethics of his role as both Pro Disc Investigator as an investor in the company that manufactured the Pro Disc implant.
Quoted in USA Today article when actor Jason Priestley received injuries in a race-car accident
Quoted in Cnn.com article on actor Christopher Reeve's spinal cord injury
Quoted in Orthopedic Tech Review's Industry News section about Christopher Reeve's condition
Recognized in the Miami Project to Cure Paralysis' newsletter, delivering an honor as ASIA President to a fellow scientist, Damien Pearse, PhD
Quoted on Raleigh-Durham ABC affiliate's website discussing nonfusion surgical devices
Publications
Zigler is a contributing eEditor to Spine Trauma and Spinal Arthroplasty, authoritative medical textbooks. He has authored over 45 articles and chapters in internationally-read peer-reviewed medical journals and books.