Prolotherapy injections for chronic low-back pain

Chronic low-back pain is a very common problem for which there is currently no universally effective treatment. Patients with chronic low-back pain have many treatment options and it is important for them to understand the evidence behind each treatment option they may be considering. Prolotherapy injections have been used to treat chronic low-back pain for over 50 years but their use remains controversial. They involve repeatedly injecting ligaments with compounds such as dextrose (sugar) and lidocaine (anaesthetic) to help restart the body's natural healing process by causing controlled acute inflammation (swelling) in the areas injected. Proponents believe this leads to stronger ligaments that can better support the low-back. Prolotherapy injections are often combined with other treatments such as spinal manipulation, exercises, and corticosteroid injections into tender muscles to maximize its effect.

This review included five studies that examined the effects of prolotherapy injections on 366 patients with low-back pain that had lasted for longer than three months. Because these studies used different types of prolotherapy injections and different treatment protocols, their results could not be combined. The five studies we examined were therefore divided according to whether they used prolotherapy injections alone or combined prolotherapy injections with spinal manipulation, exercise, and other treatments. Of the five studies we reviewed, three found that prolotherapy injections alone were not an effective treatment for chronic low-back pain and two found that a combination of prolotherapy injections, spinal manipulation, exercises, and other treatments can help chronic low-back pain and disability. Minor side effects such as increased back pain and stiffness were common but short-lived. Based on these five studies, the role of prolotherapy injections for chronic low-back pain is still not clear.

Authors' conclusions: 

There is conflicting evidence regarding the efficacy of prolotherapy injections for patients with chronic low-back pain. When used alone, prolotherapy is not an effective treatment for chronic low-back pain. When combined with spinal manipulation, exercise, and other co-interventions, prolotherapy may improve chronic low-back pain and disability. Conclusions are confounded by clinical heterogeneity amongst studies and by the presence of co-interventions.

Read the full abstract...

Prolotherapy involves repeated injections of irritant solutions to strengthen lumbosacral ligaments and reduce some types of chronic low-back pain; spinal manipulation and exercises are often used to enhance its effectiveness.


To determine the efficacy of prolotherapy in adults with chronic low-back pain.

Search strategy: 

We searched CENTRAL 2006, Issue 3 and MEDLINE, EMBASE, CINAHL, and AMED from their respective beginnings to October 2006, with no restrictions on language, and consulted content experts. Literature search was updated on July 29th, 2009. No new RCTs were identified.

Selection criteria: 

We included randomised (RCT) and quasi-randomised controlled trials (QRCT) that compared prolotherapy injections to control injections, alone or in combination with other treatments, which measured pain or disability before and after the intervention.

Data collection and analysis: 

Two review authors independently selected the trials and assessed methodological quality. Intervention protocols varied from study to study, making meta-analysis impossible.

Main results: 

We identified five high quality studies with a total of 366 participants. All measured pain or disability levels at six months, and four measured the proportion of participants reporting a greater than 50% reduction in pain or disability scores.

Three randomised controlled trials (206 participants) found that prolotherapy injections alone are no more effective than control injection for chronic low-back pain and disability. At six months, there was no difference between groups in mean pain or disability scores (2 RCTs; 184 participants) and no difference in proportions who reported over 50% improvement in pain or disability (3 RCTs; 206 participants). These trials could not be pooled due to clinical heterogeneity.

Two RCTs (160 participants) found that prolotherapy injections, given with spinal manipulation, exercise, and other therapies, are more effective than control injections for chronic low-back pain and disability. At six months, one study reported a significant difference between groups in mean pain and disability scores, whereas the other study did not. Both studies reported a significant difference in the proportion of individuals who reported over 50% reduction in disability or pain. Co-interventions confounded interpretation of results and clinical heterogeneity in the trials prevented pooling.