Complications of Biodegradable Materials: Anchors and Interference Screws.

Metal, plastic, and biodegradable implants can all cause problems. The advantage of the biodegradable implant is clarity in postoperative imaging, easier revision, and fewer concerns about associated tissue damage. Although biodegradable implants do degrade over time, this time varies considerably, depends upon the polymer present, and is often measured in years. Before that occurring, the implant is a rigid device. Problems in the operative or immediate postoperative period include implant breakage during insertion, loss of initial fixation, incompletely buried or "proud" implants within a joint that could damage articular cartilage, and possible implant migration. Later occurring problems include the development of inflammatory reactions leading to lytic changes, cyst formation, intra-articular granuloma formation along with swelling, and sterile pretibial abscesses. Despite this list of potential problems on balance biodegradable implants are safe and effective and present no greater concerns (and arguably fewer ones) than metal or plastic implants.