A review of the effect of prolotherapy injections for chronic low back pain was conducted by researchers in The Cochrane Collaboration.  After searching for all relevant studies, they found five studies done by other researchers.  Their findings are summarised below. 

What is chronic back pain and why prolotherapy?

Chronic low back pain is usually defined as low back pain that has lasted for longer than three months. Prolotherapy injections have been used to treat chronic low back pain for over 50 years but their use is controversial.

Prolotherapy involves a series of injections to the ligaments in a painful area of your body. Different solutions can be used in these injections, including dextrose (sugar); anaesthetics such as lidocaine and procaine; or combinations of these and other solutions.

Ligaments are the "rubber bands" that keep your bones together at the joints. Prolotherapy for low back pain is based on a theory that the pain is caused by slackness in the ligaments around your pelvis. If these ligaments are slack, your muscles will try to replace the reduced stability around your pelvis. This "extra work" can then lead to pain in your muscles.  By giving prolotherapy injections to the ligaments, the injections are supposed to cause an inflammation (swelling) which will help restart your body's natural healing process, strengthen your ligaments and thereby reduce pain. 

Prolotherapy can lead to several side effects. These include increased back pain and stiffness in the area where you have been injected. Some people may experience headaches or allergic reactions to the solution that is injected. A severe headache may be a sign of a lumbar puncture, i.e. that the injections have punctured your spine. All of these side effects usually pass after a few days.

Prolotherapy is sometimes given alone and sometimes in combination with other treatment, such as manipulation, injections of pain medication in tender muscles, exercise, and advice about activity or food supplements.

What does the research say?

Not all research provides the same quality of evidence. The higher the quality, the more certain we are about what the research says about an effect. The words will (high quality evidence), probably (moderate quality evidence) ormay (low quality evidence) describe how certain we are about the effect.

It is difficult to make any general conclusions about the effects of prolotherapy for people with low back pain. Participants in these studies were given different types of prolotherapy, and were compared with people who were given control injections. These control injections may also relieve pain in some patients because they contain local anesthetic.

The studies showed the following:  

• We are very uncertain whether prolotherapy improves back pain after 3 and 12 months
• There may be very little difference in pain 6 months after the injections
• There may be very little difference in disability 6 months after the injections

None of the studies measured the effect of prolotherapy on the number of people who returned to work.

In general, side effects are poorly documented and it is difficult to provide precise information. In these studies most participants experienced a temporary increase in pain and stiffness. A few percent of the participant had severe headaches which may be a sign of lumbar puncture. 

Table of results

1The numbers in the brackets show the range in which the actual effect could be.

Where does this information come from?

The Cochrane Collaboration is an independent global network of volunteers, dedicated to summarizing research about health care.

This information is taken from this Cochrane Review: Dagenais S, Yelland MJ, Del Mar C, Schoene ML. Prolotherapy injections for chronic low-back pain. Cochrane Database of Systematic  

Reviews 2007, Issue 2. Art. No.: CD004059. DOI: 10.1002/14651858.CD004059.pub3.

This summary was prepared by:

Gunn Vist and Claire Glenton, the Nordic Cochrane Centre's Norwegian branch, Norwegian Knowledge Centre for Health Services, on behalf of the Cochrane Complementary and Alternative Medicine Field, and with funding from the US National Center for Complementary and Alternative Medicine (NCCAM) of the US National Institutes of Health (grants number R24 AT001293).

Prolotherapy 3 biweekly injections for chronic low back pain

Patient or population: patients with chronic low back pain
Settings: UK
Intervention: prolotherapy 3 biweekly injections

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. Thecorresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: Confidence interval; RR: Risk ratio

GRADE Working Group grades of evidence

High quality: Further research is very unlikely to change our confidence in the estimate of effect. 

Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.

Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.

Very low quality: We are very uncertain about the estimate.

1 Unclear randomizatin procedure, allocation concealment and blinding, AND differences betwen arms in duration of pain at start of trial
2 Only one study with few events

Prolotherapy 3 wekly injections for chronic low back pain

Patient or population: patients with chronic low back pain
Settings: Hospital and general practice in UK 
Intervention: prolotherapy 3 wekly injections

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. Thecorresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: Confidence interval;

GRADE Working Group grades of evidence

High quality: Further research is very unlikely to change our confidence in the estimate of effect. 

Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.

Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.

Very low quality: We are very uncertain about the estimate.

1 Unclear randomization procedure, allocation concealment and blinding
2 Only one study, few participants / events

Prolotherapy 7 biweekly injections for chronic low back pain

Patient or population: patients with chronic low back pain
Settings: Australia
Intervention: prolotherapy 7 biweekly injections

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. Thecorresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: Confidence interval; RR: Risk ratio;

GRADE Working Group grades of evidence

High quality: Further research is very unlikely to change our confidence in the estimate of effect. 

Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.

Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.

Very low quality: We are very uncertain about the estimate.

1 Only one small study with few events