Prolotherapy is the injection of a solution — in general dextrose at high concentration — at or near a selected tendon, ligament, tendon attachment, or joint, with the purpose of creating a biological response at that particular place. This proposed mechanism should not be interpreted as evidence confirming that the injection can create a damaged structure anew.

The clinical results differ according to the disease, the method of injection, the comparison group, and the quality of the research. Prolotherapy may be a choice brought up for discussion in certain chronic musculoskeletal problems after a clear diagnosis and the giving of information to support the decision, but it is not a repair that guarantees a result, and it does not take the place of suitable rehabilitation.

The duties of ligaments and tendons

Ligaments connect bone to bone and help control the stability of the joint, while tendons connect muscle to bone and transmit force. Pain in these areas may come from an acute injury, repeated load-bearing, a reduced ability to bear load, degeneration, problems of a neighbouring joint or nerve, or pain referred from another position.

The level of pain does not directly tell the degree of damage to the tissue. The symptoms may decrease before the capacity of the tissue recovers, or may remain even though there is no severe tear. The assessment must therefore consider both the possible root causes and the activities the patient can do safely.

The proposed mechanism of prolotherapy

There is a hypothesis that dextrose at high concentration creates an osmotic and inflammatory stimulus at that particular place, which may have an effect on the signals of repair. Work in the laboratory and before trials in humans describes effects that may be connected with inflammatory mediators, fibroblasts, growth factors, and collagen processes.

However, these proposed mechanisms do not yet confirm that a patient's tendon becomes structurally stronger. Most clinical research measures pain and function, and only a small part has been able to show durable creation of new tissue. Therefore, speaking of new collagen or a stronger tendon should be a hypothesis, not a guaranteed outcome.

What does the clinical evidence say

The evidence still gives inconsistent results. A systematic review and meta-analysis of 2020 (opens in a new tab) included 10 trials with 358 participants who had problems of the tendon, the plantar fascia, or the ligaments, and concluded that the evidence is still not enough to support a clinical benefit overall.

A review of tendon states from sport of 2024 (opens in a new tab) included 20 randomised trials with 1,136 participants, and found results for pain or function that are of interest in some diseases, but the kinds of disease and the methods of treatment differ, and the researchers state that larger comparative trials are still needed.

The results also differ according to the position of the disease. A review of tendon states around the shoulder joint of 2025 (opens in a new tab) included 8 pieces of research with 431 participants and did not find prolotherapy superior to the conservative treatment of the control group or to placebo in the main outcomes reported by the patients.

Considered together, these pieces of work do not support a blanket statement that prolotherapy can repair tendons, but they do support a discussion separated by disease of the benefit that is still uncertain, the alternatives, the costs, and the risks.

The diagnosis and the selection of patients must come first

Chronic pain around a tendon may resemble a partial or a complete tendon tear, a fracture, inflammatory disease, infection, a compressed nerve, disease of the joint, or pain referred from another position. The history, the physical examination, functional tests, and imaging where there is an indication help narrow the scope of the diagnosis.

Musculoskeletal ultrasound helps in seeing certain soft-tissue structures, and helps a trained operator place the needle near a selected target, but it cannot identify the root cause of the pain in every case, and using ultrasound guidance does not guarantee the result of the treatment.

Before an injection, the doctor should review the preliminary diagnosis, previous treatment, the history of drug allergy, the medicines currently used, the risks of bleeding and infection, the relevant underlying diseases, and the patient's goals. Medicines, including anticoagulants, should not be stopped without advice from the prescribing doctor.

When might prolotherapy be discussed

It may be discussed in chronic tendon states or in certain cases of pain related to ligaments, when the diagnosis is fairly clear, the symptoms remain despite suitable conservative treatment, and the patient understands that the evidence is still uncertain.

Prolotherapy should not be used to delay the assessment of a sudden injury that comes with a loud sound in the joint, great swelling, deformity, loss of strength, being unable to bear weight, fever, a hot red joint, or neurological symptoms getting worse rapidly. These symptoms may need an urgent assessment and a different approach to treatment.

The risks and the care after injection

After an injection there may be tight pain, soreness, bruising, or a short flare-up of pain. Other possible complications are bleeding, infection, injury to nerves, blood vessels, or neighbouring tissue, and a reaction to the substance injected or to the local anaesthetic. The likelihood and the severity depend on the position, the technique, and the health of each person.

The care and the return to activity must be adjusted according to the tissue and the procedure. Medical advice should be sought quickly if there is fever, spreading redness, discharge, pain that increases continually, new weakness or numbness, or other abnormal symptoms after the injection.

Rehabilitation is still important

Managing the load and graded exercise are the main components of the rehabilitation plan for many kinds of tendon. The programme may cover muscle strength, the control of movement, balance, walking, the demands of work or sport, and the speed of increasing the load.

There is no single programme after prolotherapy that can be used with everyone. The timing and the intensity of the exercise should correspond with the diagnosis, the procedure, the sensitivity of the symptoms, and the response over time. Injection should not be used to skip the step of returning to activity gradually.

Questions before deciding

What is the preliminary diagnosis, and what evidence supports it?
Which treatment has better evidence for this disease?
What benefit can realistically be expected, and how will the pain and the function be measured?
Which solution and technique will be used, and for what reason?
Does this target suit the use of ultrasound guidance?
What are the risks, the alternatives, the total costs, and the rehabilitation plan?
When will the result be assessed, and what would be a reason to change the plan?

Frequently asked questions

Does prolotherapy create a damaged tendon anew?

There is not yet evidence to confirm it. Prolotherapy has the hypothesis that it may have an effect on the signals of repair at that particular place, but clinical research usually reports pain and function rather than confirmed creation of new structure.

How does it differ from steroid injection?

The mechanisms aimed at are different: corticosteroid is used mainly for its anti-inflammatory effect, while prolotherapy with dextrose aims to create a stimulus at that particular place. No method is the most suitable for every disease, and results from one part of the body should not be concluded to apply to another.

Does ultrasound guidance make it work?

Ultrasound helps in seeing structures and placing the needle more precisely in suitable targets, but it does not confirm the diagnosis and does not guarantee a clinical result.

How many injections are needed?

There is no universal number supported by evidence. The methods of treatment differ according to the disease and the research. The plan should set a time for reassessment and criteria for stopping, rather than guaranteeing a fixed number of sessions.

When should a medical assessment be received

An assessment should be received when the pain persists, returns when load is borne, limits daily routines, or arises after an injury. Urgent care should be received when there is a severe injury, deformity, sudden loss of function, a hot swollen joint, fever, redness increasing rapidly, or new neurological symptoms