Stem cells sound a bit like science fiction, but they’re really just your body’s “spare parts” team. In this post, you’ll learn what stem cells are, what they actually do, and why the phrase stem cell therapy can mean very different things depending on the medical setting.
What stem cells are (in plain English)
Stem cells are special cells with two standout skills. First, they can make more cells like themselves (self-renewal). Second, they can change into other types of cells that do specific jobs (differentiation).
Your body uses them to maintain and repair tissues. That’s why they’re found in many places, including bone marrow, which produces stem cells that can become different blood cells.
What stem cells do in the body
Think of stem cells as the quiet builders working behind the scenes. When tissues need topping up or repairing after damage, stem cells help create new “replacement” cells to keep things running.
In bone marrow, they help produce red blood cells (carry oxygen), white blood cells (fight infection), and platelets (help clotting). This is one of the clearest, most established examples of what stem cells do day to day.
Where stem cells are used in real medicine today
Here’s where things get practical. The most established medical use is stem cell (bone marrow) transplant, used to treat blood cancers and serious blood disorders by replacing damaged blood-forming cells with healthy ones.
This is important because it’s a highly regulated, hospital-based pathway with clear clinical standards. It’s also why the term stem cell therapy carries so much hype—because in some settings, it genuinely has a strong evidence base.
Why “stem cell therapy” can get confusing in joint pain
Outside blood conditions, stem cell research is a huge area, but not every use is equally proven. In musculoskeletal care (like knee osteoarthritis), treatments marketed as stem cell therapy are often grouped with “orthobiologic” injections—options intended to help symptoms and function by influencing inflammation and the joint environment.
But wording matters. The British Orthopaedic Association cautions that using the term “stem cells” may mislead people into thinking injected cells will turn into new cartilage or new tissue, which has not been shown for currently available preparations.
So, if you’re exploring stem cell therapy for joint pain, the smartest move is to ask what exactly is being offered, what evidence supports it for your diagnosis and stage, and what outcomes are realistic.
Conclusion
Stem cells are special repair-focused cells with the ability to renew themselves and develop into other cell types. They play a vital role in everyday tissue maintenance, and they’re used in established treatments like stem cell transplants for blood cancers and disorders. Meanwhile, stem cell therapy in orthopaedic care is a more complex, evolving area where clear definitions and honest expectations matter.
If you’re researching options for knee pain or osteoarthritis, explore our related posts on osteoarthritis and treatment planning, or contact Regenesis to discuss whether a specialist assessment could help you choose the most sensible next step.
