Stem Cell Injections: Types, Procedure, Costs, and How to Find a Qualified Provider

A cellular therapy injection, usually called a stem cell injection, places a concentrated preparation of living cells, such as bone marrow aspirate concentrate (BMAC), adipose-derived stromal vascular fraction (SVF) or umbilical cord mesenchymal stem cells (MSCs), directly into a damaged knee, hip, shoulder or tendon to support repair. According to the FDA consumer alert on regenerative medicine products, none of these products has been approved to treat any orthopedic condition, so most US patients pay cash and should weigh the evidence for their specific diagnosis carefully.

What Are Stem Cell Injections?

Stem cell injections refer to procedures in which concentrated biological preparations containing stem cells or progenitor cells are injected into damaged tissues to promote healing and reduce inflammation. The term is used broadly in clinical practice and marketing, though not all products labeled as “stem cell injections” contain the same types or concentrations of cells [1].

The goal is to harness the body’s own repair mechanisms (or those of donor cells) to restore function in damaged tissue rather than simply managing symptoms or replacing a joint surgically. The science is promising and rapidly evolving, but marketing has often outpaced the evidence. Understanding exactly what is being injected and what the data shows is the best defense against unrealistic expectations.

Is a cellular therapy injection the same as a stem cell injection?

A cellular therapy injection and a stem cell injection usually describe the same procedure: a cell-based preparation injected into one joint or tendon. Clinicians also use the terms regenerative injection, orthobiologic injection, MSC injection and cell-based therapy. The label matters less than the product, so ask which preparation is used, whether it comes from your own body (autologous) or a donor (allogeneic), and how it is processed.

Most of the biology happens through signaling rather than new tissue growth. Mesenchymal stem cells, also called mesenchymal stromal cells, release growth factors and anti-inflammatory cytokines that influence the cells already in the joint. Marks, Witten and Califf of the FDA wrote in the New England Journal of Medicine (2017) that the benefits and risks of most of these therapies still need to be established in controlled trials [1]. Readers who want the cell biology in more depth can start with the stem cell therapy treatment guide.

Types of Stem Cell Injections

Four preparations account for most cellular therapy injections in US clinics. They differ in where the cells come from, how they are processed and how the FDA regulates them, and those differences drive both cost and the questions a patient should ask.

Platelet-Rich Plasma (PRP)

PRP is not technically a stem cell product, but it is frequently grouped with stem cell injections because it falls under the same regenerative medicine umbrella and is often used alongside cell-based therapies.

PRP is produced by drawing the patient’s blood (typically 30 to 60 mL), spinning it in a centrifuge to concentrate platelets, and injecting the preparation into the target tissue. Platelets contain growth factors such as PDGF, TGF-beta, and VEGF, which support tissue repair and modulate inflammation [2].

PRP has the most clinical evidence of any regenerative injection, with systematic reviews showing benefit for knee osteoarthritis and tendon conditions like lateral epicondylitis and patellar tendinopathy [3]. It is the least expensive option and carries minimal risk. The main limitation is that PRP does not contain stem cells in meaningful numbers.

Results are not uniform. A randomized controlled trial by Filardo and colleagues in the American Journal of Sports Medicine (2015) found that PRP knee injections did not outperform hyaluronic acid (viscosupplementation) at 12 months [3]. The platelet-rich plasma treatment guide covers preparation methods and dosing in more detail.

Bone Marrow Aspirate Concentrate (BMAC)

BMAC is obtained by aspirating bone marrow (usually from the iliac crest) and concentrating it with a centrifuge. The concentrate contains MSCs, hematopoietic stem cells, platelets, growth factors, and anti-inflammatory cytokines [4]. The entire process can be completed in a single procedure without laboratory expansion, making it a true “point-of-care” therapy.

MSC concentration in BMAC varies by patient age, health status, and aspiration technique, typically ranging from 500 to 50,000 MSCs per milliliter [4]. The FDA generally considers autologous, same-day BMAC to be minimally manipulated and intended for homologous use, exempting it from premarket approval requirements [5].

Concentration also depends on the device. Hegde and colleagues (2014) compared three marketed bone marrow concentration systems and found they did not produce equivalent progenitor cell numbers [4], which is one reason two BMAC procedures at two clinics may not deliver the same product.

Adipose-Derived Stromal Vascular Fraction (SVF)

SVF is obtained from a small-volume lipoaspiration procedure (essentially a mini-liposuction), followed by enzymatic digestion or mechanical processing to separate the cellular components from the fat. The resulting SVF contains adipose-derived MSCs, endothelial progenitor cells, pericytes, macrophages, and other stromal cells [6].

Adipose tissue contains MSCs at 100 to 500 times the concentration found in bone marrow. The FDA considers enzymatic digestion of adipose tissue to be more than minimal manipulation, meaning SVF prepared with collagenase is regulated as a biologic requiring premarket approval. Mechanically processed fat (such as microfragmented adipose tissue) may fall under a different classification, though this remains debated [5].

Umbilical Cord-Derived MSCs

Allogeneic MSCs derived from umbilical cord tissue (Wharton’s jelly) or amniotic tissue represent the newest category of stem cell injectables in clinical use. These are donor-derived products, meaning the cells come from a source other than the patient.

UC-MSCs offer theoretical advantages: the cells are young, highly proliferative, and can be prepared as an “off-the-shelf” product [7]. This category also carries the most caveats. Many commercial “umbilical cord stem cell” products contain few or no viable stem cells by the time they reach the patient. Independent analyses have found that some products contain no living MSCs at all, despite being marketed as stem cell therapies [8].

Patients considering allogeneic products should ask about cell viability data, tissue bank certifications, and whether independent testing has confirmed living stem cells in the final product.

The FDA consumer alert names Wharton’s jelly, amniotic fluid, umbilical cord blood and adipose-derived products specifically and states that none has been approved for knee, hip, shoulder, neck or back pain. Related donor-derived products, such as exosomes, sit in the same regulatory gap; the exosome therapy guide explains how they differ from cell injections.

Orthopedic Applications

Knee Osteoarthritis

Knee osteoarthritis is by far the most common indication for stem cell injections. Patients with mild to moderate cartilage degeneration (Kellgren-Lawrence grades 1 through 3) are generally considered the best candidates, as these patients still have enough cartilage remaining to benefit from regenerative support. Patients with severe, bone-on-bone arthritis (grade 4) are less likely to achieve meaningful cartilage regeneration and may be better served by joint replacement [9].

Clinical studies of intra-articular stem cell injections for knee OA have generally shown improvements in pain (as measured by visual analog scales and WOMAC scores) and functional outcomes over 6 to 24 months. Some MRI-based studies have demonstrated stabilization or modest improvement in cartilage thickness, though the clinical significance of these imaging findings is still being evaluated [10].

People comparing options for knee and hip osteoarthritis usually weigh cellular injections against physical therapy, weight management, corticosteroid shots, hyaluronic acid and, eventually, total knee arthroplasty. The osteoarthritis treatment overview sets those options side by side.

Hip Degeneration

Hip osteoarthritis and labral tears are increasingly treated with regenerative injections, though the evidence base is smaller than for knee applications. Intra-articular injections for the hip typically require fluoroscopic (X-ray) guidance because the hip joint is deeper and more difficult to access than the knee. Early clinical data is encouraging, with some studies reporting pain reduction and functional improvement, though randomized controlled trials are limited [11].

Shoulder Injuries

Rotator cuff tears, particularly partial-thickness tears, are a growing application for stem cell and PRP injections. The rationale is that partial tears in tendons with poor blood supply may benefit from the growth factors and cellular support provided by regenerative injections. A systematic review of PRP and stem cell injections for rotator cuff pathology found evidence of reduced pain and improved function, with some studies showing improved tendon healing rates on follow-up imaging [12].

Tendon and Ligament Injuries

Achilles tendinopathy, plantar fasciitis, tennis elbow, and other tendon conditions have been treated with PRP and stem cell injections with varying degrees of success. PRP has the strongest evidence in this category, with multiple randomized trials supporting its use for chronic tendinopathy that has not responded to conservative treatment [3].

For lateral epicondylitis, the tennis elbow condition page lists the conservative steps most clinicians try first, and the plantar fasciitis page does the same for heel pain. A cellular injection is usually considered only after several months of bracing, stretching and physical therapy have not helped.

What conditions are stem cell injections not suited for?

Stem cell injections are a local treatment for a specific joint or tendon. Turner and Knoepfler (2016) found that US direct-to-consumer stem cell businesses marketed the same products for conditions as different as autism, COPD, Parkinson’s disease and knee pain [13]. The FDA consumer alert states that no stem cell product has been approved for neurological, cardiovascular or lung disease, autism, macular degeneration, chronic pain or fatigue. For those diagnoses, a registered study listed on ClinicalTrials.gov is a more responsible place to look than a cash-pay clinic.

Who Performs Stem Cell Injections?

Cellular therapy injections for joints and tendons are usually performed by physicians who already do image-guided musculoskeletal injections. The most common specialties are:

• Physical medicine and rehabilitation (PM&R) physicians, also called physiatrists, who often hold fellowship training in sports or interventional spine medicine.
• Sports medicine physicians, board certified in a primary specialty such as family medicine or PM&R with added sports medicine certification.
• Orthopedic surgeons, who can also judge whether a joint is past the point where an injection is reasonable and surgery is the better option.
• Interventional pain physicians, typically trained in anesthesiology or PM&R, who use fluoroscopy for deep joints and the spine.

Nurse practitioners and physician assistants perform injections in some states under physician supervision, and scope of practice rules differ by state. Whoever does the procedure, a physician should review your history, examination and imaging first, and the injection should be placed under ultrasound or fluoroscopic guidance.

What the Procedure Looks Like

Pre-Procedure

Before a stem cell injection, patients typically undergo a clinical evaluation and imaging (X-ray and/or MRI) to assess the extent of tissue damage and confirm candidacy. Many providers recommend stopping non-steroidal anti-inflammatory drugs (NSAIDs) 1 to 2 weeks before the procedure, as these medications may inhibit platelet function and interfere with the healing response. Blood thinners may also need to be adjusted in consultation with the prescribing physician.

Harvesting (If Autologous)

For BMAC, bone marrow aspiration is performed from the posterior iliac crest under local anesthesia. A specialized needle is inserted into the marrow space, and the aspiration takes 15 to 30 minutes. The aspirate is processed in a bedside centrifuge to concentrate cells and platelets.

For SVF, a small lipoaspiration is performed under local anesthesia from the abdomen or flanks. For allogeneic products, no harvesting is needed; the product arrives frozen or fresh from a tissue bank.

The Injection

The cell preparation is injected into the target tissue using image guidance. Ultrasound ensures accurate placement for joints and tendons, while fluoroscopy (live X-ray) is used for deeper joints like the hip. The injection is similar to a cortisone injection in technique, with the entire procedure taking 30 to 60 minutes.

Step by step on the day

1. The physician confirms the target joint or tendon with a brief examination and reviews your imaging.
2. For autologous products, the harvest site (hip bone or abdomen) is numbed and the bone marrow or fat is collected.
3. The sample is processed in a centrifuge or processing kit while you rest, or a donor product is thawed.
4. The injection site is cleaned and numbed, and the needle is guided into place with ultrasound or fluoroscopy.
5. The preparation is injected, a bandage is applied and you receive written activity restrictions before going home the same day.

Recovery Timeline

Recovery from a stem cell injection is generally straightforward compared to surgical alternatives:

• Days 1 to 3: Mild to moderate soreness and swelling at the injection site. Ice, elevation, and acetaminophen (not NSAIDs) are typically recommended.
• Week 1 to 2: Gradual reduction in post-procedure soreness. Most patients can return to desk work and light daily activities within a few days.
• Weeks 2 to 6: Progressive return to normal activities. Low-impact exercise (walking, swimming, stationary cycling) is usually encouraged. High-impact activities and heavy lifting are typically restricted.
• Months 2 to 6: Gradual improvement in symptoms as the biological response develops. The full benefit of stem cell injections may not be apparent for 3 to 6 months, as tissue remodeling and repair are slow processes.

Many protocols pair the injection with a structured physical therapy program during weeks 2 to 6. Loading the joint or tendon gradually is part of how the tissue responds, so ask the clinic who designs and supervises that rehabilitation.

Cost and Insurance

Stem cell injections are rarely covered by health insurance in the United States, as most commercial payers and Medicare consider them experimental or investigational. Out-of-pocket costs vary widely depending on the type of product, geographic location, and clinic pricing structure.

• PRP injection: $500 to $2,000 per treatment
• BMAC (bone marrow concentrate): $3,000 to $7,000 per treatment area
• SVF (adipose-derived): $4,000 to $8,000 per treatment area
• Allogeneic MSC products: $3,000 to $10,000+ per treatment area

Some clinics offer package pricing for multiple joints or combination protocols. Be wary of clinics offering large discounts for upfront payment or high-interest financing. Weigh the cost against the alternatives: physical therapy, cortisone injections, viscosupplementation, and surgical intervention.

What a quoted price should include

A written quote should list the consultation, imaging, harvest, processing, the injection itself, image guidance and any follow-up visits as separate lines. Ask whether a second injection is included or billed separately, and whether the price changes if both knees are treated. A breakdown by joint and region is in the post on stem cell therapy cost.

How Strong Is the Evidence for Stem Cell Injections?

The evidence for stem cell injections is encouraging for some orthopedic uses and thin for most others. The strongest data come from knee osteoarthritis and chronic tendinopathy, and much of it comes from case series, small cohorts and trials without a placebo injection.

• Knee osteoarthritis: Chahla and colleagues (2016) systematically reviewed concentrated bone marrow aspirate for knee cartilage injury and osteoarthritis and reported improved pain and function, while noting that the included studies were mostly low level evidence [10].
• PRP versus hyaluronic acid: Filardo and colleagues (2015) randomized knee patients to PRP or viscosupplementation and found no superiority for PRP [3].
• Hip osteoarthritis: Mardones and colleagues (2017) reported pain and function gains after MSC injections in a small case series, without a control group [11].
• Safety outside trials: Bauer and colleagues (2018) catalogued adverse events after unproven stem cell interventions, including infections, tumors and vision loss [14].

Placebo response is large in knee pain trials, which is why uncontrolled before and after results tend to look better than controlled ones. To see which cellular therapy trials are recruiting near you, search the ClinicalTrials.gov registry run by the National Library of Medicine.

How the FDA Regulates Stem Cell Injections

The FDA regulates stem cell injections as human cells, tissues and cellular and tissue-based products (HCT/Ps) under 21 CFR Part 1271. A product that is minimally manipulated, intended for homologous use and that meets the other criteria in 21 CFR 1271.10 can be marketed under Section 361 of the Public Health Service Act without premarket approval [5].

Products that fail those tests, such as culture-expanded MSCs or enzymatically digested SVF, are regulated as biologics under Section 351 and need an approved Biologics License Application or an investigational new drug (IND) exemption to be given to patients. The FDA has issued warning letters to clinics marketing such products without either. The post on which stem cell products the FDA has approved covers that question in more detail.

Patients who are harmed after any regenerative medicine product can report it to the FDA through the MedWatch adverse event reporting program.

Stem Cell Injections Compared With Other Joint Injections

Cellular therapy injections sit between conservative care and surgery. The options below are the ones a physician usually discusses alongside them.

PRP is the option most often compared head to head with stem cells, and the PRP versus stem cell therapy comparison covers that choice. Prolotherapy is an older, lower-cost injection some physicians try first for ligament laxity.

How to Vet a Provider

The stem cell injection market includes both highly qualified, evidence-based practitioners and unscrupulous operators making exaggerated claims. Knowing how to evaluate a provider is one of the most consequential decisions a patient can make.

Questions to Ask

• What exactly is being injected? A qualified provider should be able to tell you precisely what product they use, where it comes from, and what it contains. Vague answers (“stem cells” without specifics) are a red flag.
• What is the evidence for this treatment in my condition? Good providers will be honest about the current state of the evidence, including its limitations.
• How many of these procedures have you performed? Experience matters. Ask about their training in regenerative medicine specifically.
• Do you use image guidance? Injections without ultrasound or fluoroscopy guidance have lower accuracy and should generally be avoided for joint and tendon applications.
• What outcomes can I realistically expect? A trustworthy provider will discuss realistic expectations rather than promising a permanent fix or certain results.
• Where do your allogeneic products come from? If using donor-derived products, the provider should be able to name the tissue bank and provide cell viability data.
• Is this product being given under an FDA investigational new drug application? For culture-expanded or donor cells, a clinic should be able to show an IND number or a ClinicalTrials.gov registration.

Red Flags

• Promises of certain or permanent results. No legitimate stem cell provider can promise an outcome. The biology is too variable and the evidence too early for such promises.
• Treating every condition with the same product. Clinics that offer stem cell injections for an implausibly broad range of conditions (autism, COPD, Parkinson’s, heart disease, and knee pain all under one roof) should raise serious concerns [13].
• High-pressure sales tactics. Aggressive marketing, limited-time offers, and free seminar-to-sale pipelines are common in the direct-to-consumer stem cell market and are not characteristic of evidence-based medical practice.
• No physician evaluation before treatment. A proper clinical evaluation, including history, physical examination, and imaging review, should precede any injection recommendation.
• Unwillingness to discuss risks or alternatives. Every procedure has risks. A provider who cannot or will not discuss complications, alternative treatments, or the possibility that the injection may not work is not practicing good medicine.
• Intravenous stem cell infusions for orthopedic problems. For joint-specific problems, cells should generally be injected directly into the target tissue. IV infusions for localized orthopedic issues lack a strong mechanistic rationale and may indicate a provider focused on revenue rather than outcomes.

Using the Regenerated.com directory to compare providers

The national list of stem cell therapy clinics lets you filter by state and city and read each profile against the questions above. Listing order is not paid ranking. Featured slots are labeled and capped, Verified means a clinic has completed credential checks rather than paid for placement, and Regenerated.com is free for patients. Inclusion in the directory is not an endorsement, so the questions about product, evidence and image guidance still apply to every clinic you contact. The guide to Featured, Verified and organic listings explains each label.

Safety Considerations

When performed by qualified practitioners using properly prepared products, stem cell injections have a generally favorable safety profile. The most common adverse events are:

• Pain and swelling at the injection site (expected and temporary)
• Temporary stiffness in the treated joint
• Rare: infection at the injection or aspiration site
• Rare: nerve or blood vessel injury during the procedure

More serious complications have been reported with unregulated products and unqualified providers, including infections from contaminated products and vision loss from unproven intraocular stem cell injections [14]. The FDA has issued multiple warning letters to clinics marketing unapproved products.

Who should avoid stem cell injections?

Physicians generally postpone a cellular injection when there is an active infection in or near the joint, an active cancer or recent cancer treatment, a bleeding disorder or anticoagulation that cannot be paused safely, or pregnancy. Severe bone-on-bone osteoarthritis is a relative reason to look at surgery instead. Discuss any of these with the physician before the harvest is scheduled.

Frequently asked questions

What is a cellular therapy injection?

A cellular therapy injection delivers a concentrated preparation of cells, most often bone marrow aspirate concentrate, adipose-derived stromal vascular fraction or donor umbilical cord mesenchymal stem cells, into an injured joint or tendon. The cells release growth factors and anti-inflammatory signals that may support repair. It is the same procedure most clinics call a stem cell injection, and according to the FDA no such product has been approved for any orthopedic condition.

Do stem cell injections work for knee pain?

Stem cell injections can reduce knee pain for some people with mild to moderate osteoarthritis, Kellgren-Lawrence grades 1 to 3, with studies reporting improvements over 6 to 24 months. Most of that research is small and uncontrolled, so results are not predictable for any one person. People with bone-on-bone, grade 4 arthritis are less likely to benefit and may do better discussing knee replacement with an orthopedic surgeon.

Does insurance cover stem cell injections?

Insurance rarely covers stem cell injections in the United States, because Medicare and most commercial insurers classify them as experimental or investigational. Patients usually pay the full cost, which varies by product and region, and should ask for a written, itemized quote. Health savings account eligibility depends on the plan administrator. Corticosteroid shots, physical therapy and joint replacement are more often covered.

How long does it take for a stem cell injection to work?

Most people notice soreness for 1 to 3 days, gradual improvement over the following weeks and the fullest effect 3 to 6 months after a stem cell injection. Tissue remodeling is slow, so a lack of change at 4 weeks is not unusual. Physicians typically reassess at the 3 and 6 month marks before discussing whether a repeat injection or another option makes sense.

Are stem cell injections FDA approved?

No stem cell injection is FDA approved for knee, hip, shoulder, back or tendon conditions. The FDA states that the only approved stem cell products in the United States are cord blood-derived blood-forming cells for disorders of the blood system. Same-day autologous BMAC can be offered without premarket approval because it is minimally manipulated, while expanded or enzymatically processed cells require an approved application or a clinical trial.

Is PRP the same as a stem cell injection?

PRP is not a stem cell injection, although clinics often offer the two together. Platelet-rich plasma is made by spinning 30 to 60 mL of your own blood to concentrate platelets and their growth factors, and it contains few stem cells. PRP is cheaper, has more randomized trial data for tendon problems and is often tried before a bone marrow or fat-derived cellular injection.

The Bottom Line

Stem cell injections are a promising but still-evolving area of medicine. For the right patients and indications, they may offer meaningful pain relief and functional improvement with less downtime than surgery. The best approach is to seek board-certified physicians with regenerative medicine training, ask detailed questions, set realistic expectations, and consider whether a registered clinical trial might be the most responsible path.

A cellular therapy injection is a cash-pay, image-guided procedure whose evidence is strongest for early knee osteoarthritis and chronic tendon problems, and no stem cell product is FDA approved for those uses. When you are ready to compare physicians, start with the PRP and regenerative injection clinics or the stem cell therapy list above, and take the vetting questions with you.

Related Reading

• Stem Cell Therapy: Complete Guide
• Mesenchymal Stem Cells: Sources, Mechanisms, and Applications
• Peptide Therapy: Complete Guide
• Peptide Injections: Types, Technique, and What to Know

Sources

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