SpinalMotion, a developer of “investigational” artificial discs for treating patients with degenerative disc disease, said it has raised $20 million in a third round of venture capital.

Skyline Ventures led the round, joined by MedVenture Associates. Early investors Thomas Weisel Healthcare Ventures and Three Arch Partners also participated, the company said

From the company’s release:

SpinalMotion continues to make significant progress on two United States (U.S.)-based Investigational Device Exemption (IDE) clinical trials for the Kineflex® lumbar disc and Kineflex®|C cervical disc implants. More than 550 patients are enrolled in the studies; over 70 percent of the required number of patients.

In South Africa, nearly 850 lumbar discs and over 350 cervical discs are implanted, bringing the total number of Kineflex discs implanted worldwide to over 1,500. In addition to its ongoing clinical trials, the company continues to work on its posterior lumbar disc.

The SpinalMotion Kineflex lumbar disc and the Kineflex|C cervical disc are second-generation, metal-on-metal designs intended to preserve motion with low wear. They feature a proprietary, straight-forward implant technique that includes specialized instruments for accurate placement. Both discs are currently approved for sale in South Africa, where they were developed.

SpinalMotion received IDE approvals in 2005 from the U.S. Food and Drug Administration (FDA) to commence the studies, which began during the second quarter. The lumbar trial involves 25 U.S. sites. In this randomized study, the investigational SpinalMotion Kineflex lumbar disc is being compared to another FDA-approved lumbar artificial disc. The cervical trial involves 20 U.S. sites and features a randomized study comparing the investigational SpinalMotion Kineflex|C to fusion. Both trials are designed to demonstrate equivalent clinical success rates to their respective controls. A two-year follow-up period is planned for both trials.

About the Artificial Disc Market

The National Center for Health Statistics reports that 14% of new patient visits to physician offices (approximately 13 million annually) are for complaints of low back pain. In fact, an estimated 18% of the population has debilitating back pain at any given time. These demographics, along with the tremendous costs to society and the focus on new treatments, have made spinal implants the fastest growing segment of the orthopedic market.