A cell can be called a “stem cell” if it has the capacity to differentiate into multiple types of cells and is able to self-renew. The ability of a stem cell to generate daughter cells ,which can then terminally differentiate into specialized tissues such as bone, tendon, and cartilage makes them “pluri-potential”, and invaluable for medical therapeutic application.
Stem cells are of two basic types:
- Embryonic stem cells which are found in the early developmental phase of an individual. They are derived from a 4-5 day old embryo. These cells are currently investigational only, for orthopedic application, and are not used currently for clinical orthopedic application.
- Mesenchymal stem cells are found in adults. Mesenchymal stem cells (MSCs) are considered to be an orthobiologic substance. They can be isolated from a number of mesenchymal tissues like bone marrow, fat, synovial membrane, periosteum and others.