What regenerative medicine means when your joint hurts

What to understand about the treatment name

The words regenerative treatments cover non-surgical choices made with material from your blood or tissue. The name describes a group of treatments, not a sure result.

One such choice is PRP, which spells out as platelet-rich plasma and comes from your blood. The clinic spins a small blood sample and keeps a portion with extra platelets.

Platelets are small pieces in blood that carry growth factors, which are proteins used during healing. That doesn't mean PRP will rebuild a surface worn by years of use.

Concentrated PRP has a greater share of platelets than some other forms. Ask what is in the treatment because clinics can handle the blood differently.

Orthobiologics is another medical word you may hear for care made from blood or tissue. It tells you where the material starts, not how well it will work.

What to ask before choosing this care

Start with the reason your joint hurts instead of the treatment name. Ask the doctor to connect the exam findings with your ache or stiffness.

Then ask what the offered care might change in daily life. A clear answer covers possible relief, limits, cost, and the time after treatment.

Human studies haven't shown steady rebuilding of worn joint surfaces. Some people feel less sore, while others notice little or no change.

The blood used for PRP is yours rather than a donor's. That removes the question of matching donated blood, but it can't predict your result.

When to get a different problem checked first

Redness, heat, swelling, and fever together can mean an infected joint. Seek prompt medical help instead of waiting for a regular appointment.

After a fall, a leg that cannot hold your weight may be broken and needs medical care soon, especially if the joint has also changed shape or swollen quickly. A joint that locks and won't move also needs quick attention.

New numbness, weakness, or losing control of your bladder or bowels may involve a nerve. Those problems need urgent care, not a visit for long-term soreness.

For a steady ache without these signs, note the sore area and painful motions. Your notes will help the doctor focus the exam.

Sources

1. Arnold Caplan, who NAMED mesenchymal stem cells more than 25 years earlier, argued in Stem Cells Translational Medicine that the name should be changed. His stated reason is exactly the marketing problem: because MSCs are called 'stem cells', patients infer they will receive direct medical benefit, imagining the cells will differentiate into regenerating tissue-producing cells - and hundreds of clinics and trials now use human MSCs with very few focusing on the in vitro multipotential capacities the name refers to.

   Caplan AI, et al. — Mesenchymal Stem Cells: Time to Change the Name!. Stem cells translational medicine, 2017. DOI: 10.1002/sctm.17-0051.

2. A JBJS systematic review screened 420 papers on intra-articular cellular therapy for knee OA and focal cartilage defects and found only SIX at Level III evidence or higher (4 Level II, 2 Level III), covering 300 knees, with wide variation in cell source, cell characterisation, adjuvant therapy and outcome assessment - meaning no consensus exists on indications, cell sources, preparation or delivery. Two products called 'stem cell therapy' at two clinics may share almost nothing.

   Chahla J, et al. — Intra-Articular Cellular Therapy for Osteoarthritis and Focal Cartilage Defects of the Knee: A Systematic Review of the Literature and Study Quality Analysis.. The Journal of bone and joint surgery. American volume, 2016. DOI: 10.2106/JBJS.15.01495.

3. A Level-1a systematic review of 87 randomized PRP-for-knee-OA trials (7,925 patients, 8,118 knees) scored them against the 23-item MIBO reporting checklist. The overall MIBO score was 72%, 71% of studies scored below 80%, and reporting was worst on exactly the items that define the product: whole-blood characteristics (20%), platelet recovery rate (22%), PRP analysis (30%), PRP activation (47%). Adherence did not improve after MIBO was published. Much of the PRP literature does not say what was actually injected.

   Nakagawa HF, et al. — Systematic Review of Randomized Controlled Trials Evaluating the Use of Platelet-Rich Plasma for Knee Osteoarthritis: Adherence to Minimum Information for Studies Evaluating Biologics in Orthopaedics.. The American journal of sports medicine, 2025. DOI: 10.1177/03635465241249996.

4. MACI (autologous cultured chondrocytes on a porcine collagen membrane, Vericel; STN BL 125603) IS an FDA-LICENSED cell therapy - and its approved indication is narrow and specific: repair of symptomatic, single or multiple FULL-THICKNESS cartilage defects OF THE KNEE, with or without bone involvement, in adults. It is not approved for osteoarthritis. The existence of one licensed cartilage cell therapy for focal defects is the sharpest available way to show what a licensed 'regeneration' product actually looks like, and how far it is from an injection for a worn joint.

   US Food and Drug Administration, Center for Biologics Evaluation and Research — MACI (autologous cultured chondrocytes on porcine collagen membrane). FDA, 2024.

5. FDA's guidance on the 21 CFR 1271.10(a) criteria of MINIMAL MANIPULATION and HOMOLOGOUS USE is the rule that decides whether a cell or tissue product may be offered as a lightly-regulated 'section 361' HCT/P or requires full drug approval as a 'section 351' biologic. Docket FDA-2017-D-6146; the revised July 2020 version extended the agency's period of enforcement discretion through 31 May 2021 - which has now expired, so products outside 361 need an approved application or an active IND.

   US Food and Drug Administration, CBER and CDRH — Regulatory Considerations for Human Cells, Tissues, and Cellular and Tissue-Based Products: Minimal Manipulation and Homologous Use. FDA, 2020.