How do regenerative injections actually work?

The mechanism they share

Injured tendons, ligaments, and joint surfaces often have poor blood supply, which is part of why they heal slowly or stall out entirely. Regenerative injections are built around the idea of concentrating healing signals at the site where the body is struggling to deliver them on its own — platelets carrying growth factors in the case of PRP, oxygen and ozone in the case of Prolozone, cell preparations in the case of stem cell therapy.

In each case the injection is a delivery method, not the treatment in itself. What is being delivered, and whether the target tissue can respond to it, is what actually differs between the options.

Why they are described as regenerative rather than palliative

A cortisone injection reduces inflammation and can relieve pain effectively, but it does not aim to change the underlying tissue — and repeated use has been associated with cartilage and tendon concerns over time. Regenerative injections are aimed at the tissue itself, which is why the response tends to build over weeks rather than appearing within days.

That slower arc is a normal part of how these therapies are expected to behave. It also means the honest measure of success is how the joint feels at six to twelve weeks, not the morning after.

Where the evidence currently stands

The research base is uneven across these therapies. PRP for certain conditions, particularly knee osteoarthritis and some tendinopathies, has the most published support. Prolozone and stem cell therapy for orthopedic use have a thinner evidence base, and stem cell therapy for these purposes is not FDA-approved and is considered investigational.

Any provider describing all three as equally proven is overstating the picture. A realistic conversation should include what is well supported, what is promising but unsettled, and what your specific imaging and history suggest is worth trying first.