What is the fine-grained topic of the following text: The NUsurface® Meniscus Implant is a novel, composite polymer implant which is used to treat knee patients who have pain and disability arising from osteoarthritis (OA) caused by a previous meniscectomy and/or meniscus dysfunction or insufficiency. Only return the topic.
NUsurface® Meniscus Implant for treating knee osteoarthritis caused by meniscus dysfunction