The knee replacement market is posting flat growth across the board as more patients seek nonsurgical options to manage their pain. Although such treatments typically last only a few months, many patients willingly accept the durability tradeoff to avoid the cost and downtime associated with surgery.

Intra-articular injections of hyaluronic acid, which mimics the lubricating properties of natural synovial fluid and lessens friction and pain in the osteoarthritic knee joint, has become increasingly popular for treating osteoarthritis. However, of the seven formulations available in the US, none have been proven clinically superior and they have only limited long-term benefit to the patient. Flex Biomedical Inc. is working to address these concerns with a single-injection synthetic polymer alternative to HA.

This Month's Profile Group: The New Ophthalmic Drug Players, features profiles of Imagen Biotech, KalVista Pharmaceuticals, ONL Therapeutics and Xcovery Vision. Plus these Start-Ups Across Health Care: Acetylon Pharmaceuticals, Aleva Neurotherapeutics, cermaVEIN and Flex Biomedical.

This article was excerpted from "Top Device Stories of 2009: A Year of Economic Revival and Regulatory Risk," IN VIVO, January 2010.