Services: Prolotherapy and Regenerative Injections

What It Is

Prolotherapy is a series of injections of an irritant solution, most often concentrated dextrose (a sugar), placed at the attachments of tendons and ligaments and inside painful joints. The aim is a small repair response at a spot that has stopped healing on its own. Platelet-rich plasma, usually shortened to PRP, is a related but distinct injection: a small amount of the patient's own blood is drawn and spun in a centrifuge to concentrate the platelets, and that platelet concentrate is injected into the same kinds of targets. Related regenerative injections include sclerosing agents for chronic tendon pain and, at the more experimental end, bone marrow or fat-derived cell preparations.

These are different injections sold on similar promises. Dextrose prolotherapy delivers no cells and no growth factors of its own; PRP delivers a concentrate of the patient's own platelets. This page covers prolotherapy and PRP, with the others noted where they overlap.

Anatomy

1Dextrose Prolotherapy

A hypertonic dextrose solution is injected at the points where tendons and ligaments anchor to bone, and sometimes into the joint space itself. Treatment is a course of several sessions weeks apart, not a single shot. The dextrose carries no growth factors of its own; the target is the local tissue response to the injection.

2Platelet-Rich Plasma

Blood is drawn from the patient, spun in a centrifuge to separate and concentrate the platelets, and the platelet-rich fraction is injected into the joint or tendon. Platelets carry growth factors, the proposed active ingredient. How the blood is spun sets the platelet dose and the white-cell content, and those differ a great deal between clinics and studies.

3Where They Are Used

The targets are almost all musculoskeletal: the knee in osteoarthritis, the outer elbow in tennis elbow, the shoulder in rotator cuff problems, the knee tendon in Osgood-Schlatter disease, and the low back. PRP is also marketed for hair and skin, which sit outside the scope of this page.

How It Works

The two injections are thought to work by different routes, and both are still being studied. Dextrose prolotherapy is proposed to set off a brief, controlled local response in connective tissue, a mild inflammatory or proliferative stimulus at an area that has stopped healing. PRP is proposed to work by delivering a concentrated dose of the growth factors platelets carry, the signaling molecules involved in tissue repair. Both are plausible, and neither is settled: a narrative review of the basic science concludes the mechanism of dextrose prolotherapy is not clearly known and is likely multifactorial, meaning several things acting together.

When the mechanism is not established, the case for an injection rests on the clinical trials. A treatment can help before anyone knows why. So the weight sits on what the controlled studies measured, and it explains why PRP preparation changes the result: if the growth factors are the active ingredient, then the platelet concentration, the white-cell content and the spin protocol change what is being injected, and those vary widely from one clinic to the next.

What It Does

These injections are marketed to regrow cartilage and permanently heal a worn joint or a damaged tendon. The controlled trials measure something narrower: pain scores and function, both of which improve in the better studies.

Expect a course to ease pain and improve function in the conditions the trials support. These are symptom adjuncts; the evidence does not show they regrow cartilage or rebuild a worn joint.

Three limits run through the whole literature and set how far to trust it:

• The comparator sets the apparent size. A plain saline injection eases symptoms on its own, so the benefit looks large against exercise or no injection and narrows against saline. The trials that use the harder comparator still favor the active injection, while the true size falls.
• The dextrose evidence rests on a few overlapping research groups. Much of the knee and elbow work traces to the same Hong Kong (Sit, Chung) and Rabago-Reeves teams, so the pooled results are related reads on one body of work more than independent confirmation.
• PRP is not one injection. Platelet concentration, white-cell content and spin protocol differ enormously between clinics and studies, so pooled PRP results blend products that are not the same treatment.

Where The Research Stands

Knee Osteoarthritis

The knee has the strongest evidence in this category, and it is graded moderate. A meta-analysis of 14 randomized trials in 978 people found dextrose prolotherapy reduced pain more than a placebo injection and more than noninvasive control, with the effect growing over the follow-up period and appearing dose-dependent.

How large that benefit looks turns on the comparison. Measured against exercise or no injection the gap is wide; measured against a saline injection, which itself relieves symptoms, the gap narrows. A blinded single-center trial ran that harder test, comparing dextrose against saline over a year, and dextrose still came out ahead on WOMAC pain, function and quality of life, improving WOMAC function by about 9.6 points. So the direction holds against an active control, while the true size shrinks as the comparator gets fairer. Two limits stay in view: the pooled trials differ in dose and technique, and much of this literature comes from a small number of overlapping research groups, so the exact effect is not yet pinned down.

Tendinopathy And Tennis Elbow

For lateral elbow tendinosis, the condition most people call tennis elbow, a meta-analysis of eight randomized trials in 354 patients found dextrose prolotherapy reduced pain and improved arm function at 12 weeks compared with other active treatments, with a large, consistent gain on the arm-function score. The comparators were other active treatments, not placebo, and the follow-up window was short, so durability is less certain. Prolotherapy has also been tested for Osgood-Schlatter disease, the knee-tendon pain of growing adolescents: a double-blind trial of 70 young patients found ultrasound-guided dextrose improved knee scores more than saline at 3, 6 and 12 months, while both groups improved. These are emerging signals from small trials.

Chronic Low Back Pain

The low back is where the evidence is weakest and most mixed. A Cochrane review of five high-quality trials in 366 participants found that prolotherapy injections on their own were no more effective than control injections for pain and disability at six months. Trials that combined prolotherapy with spinal manipulation, exercise and other therapies suggested some advantage, but inconsistently across studies, and the protocols varied so much that they could not be pooled. Dextrose injections alone are not supported for chronic low back pain; any role is as part of a broader program of manipulation and exercise.

Platelet-Rich Plasma

PRP has the largest and the most conflicting literature. For knee osteoarthritis, a meta-analysis of 18 level-1 randomized trials in 1,608 patients found PRP produced larger symptom improvement than hyaluronic acid injection, with the low-white-cell (leukocyte-poor) preparation performing best.

For tennis elbow, a meta-analysis of 11 trials in 730 patients found a clear time pattern: corticosteroid injection relieved pain faster in the first weeks, while PRP came out ahead at six months and beyond, so which treatment looks better depends on when it is measured. For rotator cuff tendinopathy, a review of eight trials linked PRP to better long-term pain and shoulder function, and reported it as safe.

The recurring caveat across all of it is preparation: platelet concentration, white-cell content and spin protocol differ enormously between studies, so pooled PRP results combine products that are not the same injection.

The Research & Studies

Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.

Pain

Dextrose cut knee osteoarthritis pain more than placebo across 14 trials in 978 peopleModerate

In plain terms

Pooling 14 trials, people with knee arthritis who had dextrose injections reported less pain than those given a placebo injection, and the benefit built up over time.

In detail

Chen and colleagues pooled 14 randomized controlled trials enrolling 978 patients. Compared with placebo injection and with noninvasive control therapy, dextrose prolotherapy had favorable effects on pain, global function and quality of life across the overall follow-up, with larger pain reductions at later time points, which the authors read as dose-dependent and time-dependent effects. Against other invasive injections the effects were broadly comparable. Combined intra-articular and extra-articular injection produced stronger pain effects than intra-articular injection alone.

The study · 1

Chen et al., effectiveness, compliance and safety of dextrose prolotherapy for knee osteoarthritis · Clin Rehabil 2022;36(6):740-752

Dextrose eased tennis elbow pain and improved arm function at 12 weeks across eight trials (354 patients)Moderate

In plain terms

Across eight trials, people with tennis elbow who had dextrose injections had less pain and better arm function at three months than those given other active treatments.

In detail

Zhu and colleagues pooled eight parallel or crossover randomized trials in 354 patients with lateral elbow tendinosis. At 12 weeks dextrose prolotherapy lowered pain versus active controls (SMD -0.44, 95% CI -0.88 to -0.01, moderate heterogeneity I2=49%) and improved function on the Disabilities of the Arm, Shoulder and Hand score (mean difference -15.04, 95% CI -20.25 to -9.82, low heterogeneity I2=0%). No major related adverse events were reported. The comparators were other active non-surgical treatments, not placebo.

The study · 1

Zhu et al., effects of hypertonic dextrose injection (prolotherapy) in lateral elbow tendinosis: a systematic review and meta-analysis · Arch Phys Med Rehabil 2022;103(11):2209-2218

PRP improved knee osteoarthritis symptoms more than hyaluronic acid (44.7% vs 12.6% on WOMAC, 18 trials)Moderate

In plain terms

Pooling 18 high-quality trials, PRP injections improved knee arthritis symptoms more than hyaluronic acid injections, and the low-white-cell preparation did best.

In detail

Belk and colleagues meta-analyzed 18 level-1 randomized trials, 811 patients receiving PRP and 797 receiving hyaluronic acid, mean follow-up 11 months. Mean WOMAC total improvement was 44.7% with PRP versus 12.6% with hyaluronic acid. Six of 11 VAS-based studies and three of six IKDC-based studies favored PRP; leukocyte-poor PRP outperformed leukocyte-rich on the subjective IKDC score. The comparator here is hyaluronic acid, itself a symptomatic injection, not a placebo.

The study · 1

Belk et al., platelet-rich plasma versus hyaluronic acid for knee osteoarthritis: a systematic review and meta-analysis of RCTs · Am J Sports Med 2021;49(1):249-260

Dextrose beat saline for Osgood-Schlatter knee pain at 3, 6 and 12 months (70 adolescents)Emerging

In plain terms

In a trial of 70 adolescents with Osgood-Schlatter knee pain, dextrose injections improved knee scores more than saline, while both treatments helped.

In detail

Wu and colleagues ran a double-blind randomized trial in 70 patients with Osgood-Schlatter disease, comparing ultrasound-guided hyperosmolar 12.5% dextrose against saline. The dextrose group gained more on the VISA-Patella score at 3 months (mean difference 25.4), 6 months (6.2) and 12 months (5.5). Both groups improved clinically, which the authors read as both being active treatments, with dextrose improving faster than spontaneous recovery would explain.

The study · 1

Wu et al., hyperosmolar dextrose injection for Osgood-Schlatter disease: a double-blind, randomized controlled trial · Arch Orthop Trauma Surg 2022;142(9):2279-2285

For chronic low back pain, dextrose alone was no better than control injections across five trials (366 people)Emerging · mixed

In plain terms

For ongoing low back pain, dextrose injections on their own worked no better than control injections, and results were mixed when the injections were paired with other treatments.

In detail

Dagenais and colleagues (Cochrane) included five high-quality studies with 366 participants. Three trials (206 participants) found prolotherapy alone no better than control injection for pain and disability at six months, and these could not be pooled because the protocols differed too much. Two trials (160 participants) that added spinal manipulation, exercise and other therapies found some advantage, but inconsistently across the two studies. The review concluded the evidence does not support prolotherapy alone for chronic low back pain.

The study · 1

Dagenais et al., prolotherapy injections for chronic low-back pain (Cochrane review) · Cochrane Database Syst Rev 2007;(2):CD004059

Steroid relieved tennis elbow faster, but PRP led by six months (VAS -2.18, 11 trials)Emerging

In plain terms

For tennis elbow, steroid injections beat PRP in the first weeks, but PRP came out ahead by six months and beyond.

In detail

Xu and colleagues pooled 11 randomized trials in 730 patients comparing PRP with corticosteroid for lateral epicondylitis. Short-term (under two months) PRP was worse on VAS pain (MD 0.93) and DASH function (MD 10.23). Long-term (six months or more) PRP was better on VAS (MD -2.18, 95% CI -3.13 to -1.22), DASH (MD -8.13) and Mayo Elbow Performance Score. The medium-term difference was not statistically significant. Heterogeneity was high for several endpoints.

How to use it

If the aim is fast relief, a steroid injection acts sooner; if the aim is where the elbow sits at six to twelve months, the pooled trials favor PRP. The choice tracks the time horizon that matters to the person.

The study · 1

Xu et al., platelet-rich plasma has better long-term functional improvement and pain relief for lateral epicondylitis: a systematic review and meta-analysis · Am J Sports Med 2024;52(10):2646-2656

PRP linked to better long-term rotator cuff pain and shoulder function across eight trialsEmerging

In plain terms

Across eight trials, PRP injections were linked to better long-term shoulder pain and function in rotator cuff problems, with no safety flags.

In detail

A Hamid and Sazlina reviewed eight randomized trials of PRP for rotator cuff tendinopathy; six were low risk of bias for randomization. Preparation, injection technique and control interventions varied widely, with four trials comparing PRP against saline and others against rehabilitation or dry needling. Random-effects meta-analysis found PRP safe and effective for long-term pain control and shoulder function. The variation in PRP methods and comparators limits how firmly the pooled result can be stated.

The study · 1

A Hamid and Sazlina, platelet-rich plasma for rotator cuff tendinopathy: a systematic review and meta-analysis · PLoS One 2021;16(5):e0251111

Joint And Arthritis Pain

Dextrose beat saline on WOMAC function by about 9.6 points at one year (76 people)Moderate

In plain terms

In a year-long blinded trial, people who got dextrose injections moved and functioned better than people who got saline injections in the same knee.

In detail

Sit and colleagues randomized 76 patients with knee osteoarthritis to intra-articular dextrose prolotherapy or normal saline at weeks 0, 4, 8 and 16. At 52 weeks the difference-in-difference favored dextrose on WOMAC function (-9.55, 95% CI -17.72 to -1.39), WOMAC composite (-9.65), WOMAC pain (-10.34) and quality-of-life measures. No adverse events were reported. Because a saline injection is itself an active comparator that often improves symptoms, a difference in favor of dextrose is a meaningful signal.

The study · 1

Sit et al., efficacy of intra-articular hypertonic dextrose (prolotherapy) for knee osteoarthritis · Ann Fam Med 2020;18(3):235-242

Superior to exercise alone, but across just 258 patients the true size stayed uncertainEmerging · mixed

In plain terms

The early pooled evidence pointed the right way but rested on a few small studies, so how strong the effect really is was still an open question.

In detail

Sit and colleagues (2016) synthesized three randomized trials and one quasi-randomized trial totaling 258 patients. Where two studies could be pooled, prolotherapy beat exercise alone on the WOMAC composite (standardized mean difference 0.81), function (0.78) and pain (0.62) subscales, with moderate heterogeneity throughout. The authors described efficacy as uncertain and called for adequately powered, longer trials with uniform endpoints. The result shows why the tier sits below strong: the direction is consistent, and the confidence is limited by small samples and varied methods.

The study · 1

Sit et al., hypertonic dextrose injections (prolotherapy) in symptomatic knee osteoarthritis: a systematic review and meta-analysis · Sci Rep 2016;6:25247

How it works

How these injections work is not established; the leading idea is a local repair responsePreliminary · mixed

In plain terms

Nobody has pinned down exactly how these injections work; the leading idea is that the solution provokes a mild local repair response, and that is still being studied.

In detail

Reeves, Sit and Rabago review the basic science of dextrose prolotherapy, which involves injecting non-biologic solutions at soft-tissue attachments and within joints to reduce pain and improve function. They state the mechanism of action is not clearly known and is likely multifactorial. Proposed routes include a brief local inflammatory or proliferative stimulus to connective tissue; for platelet-rich plasma the proposed route is delivery of concentrated growth factors. Both remain areas of active research, not established pathways.

The study · 1

Reeves, Sit and Rabago, dextrose prolotherapy: a narrative review of basic science, clinical research and best treatment recommendations · Phys Med Rehabil Clin N Am 2016;27(4):783-823

Go Deeper

• Arthritis And Joint Pain: the condition where these injections have the best evidence, and the movement and load therapies that are the best-supported non-drug treatments for it.
• Resistance Training: the base that strengthens the muscle and connective tissue around a painful joint, and the intervention with the strongest evidence in this whole section.
• Red And Near-Infrared Light: another modality marketed for joint and tendon pain, graded per indication, where device dose and settings decide the result.
• IV Drips And NAD+: a neighboring clinic category sold on a regeneration story, and how to read a treatment where the marketing runs ahead of the outcome evidence.

The Chinese Medicine View

Prolotherapy and PRP are products of modern medicine, and there is no entry for them in the classical Chinese pharmacopoeia. No historical text assigns a channel or a nature to an injection of dextrose or concentrated platelets, and there is no traditional preparation that resembles one. What follows places the category against the tradition as a lens, not as evidence, and it borrows no classical claim, because none exists.

The tradition does reason carefully about the tissues these injections are placed in. The sinews, jin, which cover the tendons and ligaments, are governed by the Liver, and the Liver stores the Blood that nourishes them; the bones and the deeper structure of the joints are governed by the Kidney. Chronic joint and tendon pain that lingers in one spot is often read as a Bi syndrome, an obstruction where Qi and Blood no longer move freely through the area, and a common treatment principle is to move the Blood and resolve stasis so the tissue can be nourished and repaired.

Seen through that lens, an injection that provokes a local repair response and restores movement to a stuck area resembles moving Blood and freeing an obstruction. The tradition would also weigh the whole person: whether the underlying Liver Blood and Kidney essence that supply the sinews and bones are themselves sufficient, because a local intervention on a depleted constitution behaves differently from the same intervention on a strong one.

This relates a modern practice to a framework the tradition has long reasoned about; it is not a claim that Chinese medicine explains or endorses these injections. The concepts belong to the tradition as it uses them, and the evidence for any injection stands or falls on the trials.

Cautions For This Practice

Everything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.

No serious harms reported in trials, but injection-site pain and flare are common, with rare infection or nerve injury

A systematic review of seven randomized trials of proliferative injection therapy for osteoarthritis (393 participants) reported no serious adverse events, alongside considerable methodological limitations in the trials. A separate systematic review of prolotherapy for lower-limb tendinopathy and fasciopathy reported no adverse events following prolotherapy injections in any included study. The common expected effects are short-term injection-site pain and a self-limited inflammatory flare in the days after treatment. The uncommon but serious risks are those of any joint or soft-tissue injection: local or joint infection and nerve injury, both operator-dependent, which is why a skilled clinician and clean technique matter. Insurance rarely covers these injections, so cost is usually out of pocket.Krsticevic et al., proliferative injection therapy for osteoarthritis: a systematic reviewSanderson and Bryant, effectiveness and safety of prolotherapy injections for lower limb tendinopathy and fasciopathy: a systematic review

Choose The Injector Carefully

The uncommon but serious risks of these injections, joint or soft-tissue infection and nerve injury, depend heavily on who performs them and how. Ultrasound guidance and a clinician experienced with the specific joint or tendon lower the chance of a misplaced needle.

The Realistic Expectation

The trials support relief of pain and better function in selected conditions, chiefly the knee and some tendons. They do not establish that these injections regrow cartilage or reverse a worn joint. It is fair to consider a course for symptoms where the evidence supports it.

Cost And Coverage

Insurance rarely covers prolotherapy or PRP, so the cost is usually paid out of pocket, and both are given as a course of several sessions. Weigh that expense against the size of the benefit the trials report, which is modest.

When A Symptom Keeps Returning

Persistent or worsening joint or back pain deserves a proper diagnosis before a course of injections. An injection can ease a symptom without addressing what is driving it, so reaching for one to quiet a recurring problem can delay finding the cause. If pain keeps coming back, get a full diagnosis first.

Start slow, be smart, read the research, and consult a professional if you have any concerns. This is here to inform your choice, not make it for you.

Common Questions

Does Prolotherapy Work For Knee Arthritis?

For the knee, the evidence is the strongest it gets in this category, graded moderate. A meta-analysis of 14 randomized trials in 978 people found dextrose prolotherapy reduced pain more than a placebo injection, and a separate blinded trial found it beat a saline injection on pain and function at one year. The benefit builds over time, though the trials vary and come largely from a few overlapping research groups, so the exact size is not yet settled.

What Is The Difference Between Prolotherapy And PRP?

They are different injections with a similar goal. Prolotherapy injects an irritant solution, usually concentrated dextrose, to provoke a local repair response, and it delivers no cells or growth factors of its own. PRP takes the patient's own blood, spins it to concentrate the platelets, and injects that platelet concentrate, so the proposed active ingredient is the growth factors platelets carry. PRP is generally more involved and more expensive, and how the blood is spun changes what is injected.

Does PRP Work For Tennis Elbow?

The trials show a clear time pattern. A meta-analysis of 11 randomized trials in 730 patients found that corticosteroid injection relieved tennis elbow pain faster in the first weeks, while PRP came out ahead at six months and beyond. So which one looks better depends on the time horizon: a steroid acts sooner, and PRP tends to lead later. Both are options, and the choice tracks whether fast relief or the longer-term result matters more.

Do These Injections Regrow Cartilage?

The controlled trials do not establish that. They measure and show improvement in pain and function for selected conditions, mainly knee osteoarthritis and some tendon problems. The idea that a course of injections regrows cartilage or permanently rebuilds a worn joint runs ahead of the evidence. The realistic expectation is symptom relief in the conditions the better trials support. These work as symptom adjuncts, not a way to reverse the underlying wear.

Are Prolotherapy And PRP Injections Safe?

Generally well tolerated, with the usual injection risks. Across systematic reviews of prolotherapy trials, no serious adverse events were reported, while short-lived injection-site pain and a flare in the days afterward are common. The uncommon but serious risks are those of any joint or tendon injection: local infection and nerve injury, both of which depend on the skill and technique of the person performing it. Insurance rarely covers these, so the cost is out of pocket. The full picture is in the cautions section above.