Spinal manipulative therapy for chronic low-back pain

Spinal manipulative therapy (SMT) is an intervention that is widely practiced by a variety of health care professionals worldwide. The effectiveness of this form of therapy for the management of chronic low-back pain has come under dispute.

Low-back pain is a common and disabling disorder, which represents a great burden to the individual and society. It often results in reduced quality of life, time lost from work and substantial medical expense. In this review, chronic low-back pain is defined as low-back pain lasting longer than 12 weeks. For this review, we only included cases of low-back pain that were not caused by known underlying conditions, for example, infection, tumour, or fracture. We also included patients whose pain was predominantly in the lower back, but may also have radiated (spread) into the buttocks and legs.

SMT is known as a "hands-on" treatment of the spine, which includes both manipulation and mobilisation. In manual mobilisations, the therapist moves the patient’s spine within their range of motion. They use slow, passive movements, starting with a small range and gradually increasing to a larger range of motion. Manipulation is a passive technique where the therapist applies a specifically directed manual impulse, or thrust, to a joint, at or near the end of the passive (or physiological) range of motion. This is often accompanied by an audible ‘crack’.

In this updated review, we identified 26 randomised controlled trials (represented by 6070 participants) that assessed the effects of SMT in patients with chronic low-back pain. Treatment was delivered by a variety of practitioners, including chiropractors, manual therapists and osteopaths. Only nine trials were considered to have a low risk of bias. In other words, results in which we could put some confidence.

The results of this review demonstrate that SMT appears to be as effective as other common therapies prescribed for chronic low-back pain, such as, exercise therapy, standard medical care or physiotherapy. However, it is less clear how it compares to inert interventions or sham (placebo) treatment because there are only a few studies, typically with a high risk of bias, which investigated these factors. Approximately two-thirds of the studies had a high risk of bias, which means we cannot be completely confident with their results. Furthermore, no serious complications were observed with SMT.

In summary, SMT appears to be no better or worse than other existing therapies for patients with chronic low-back pain.

Authors' conclusions: 

High quality evidence suggests that there is no clinically relevant difference between SMT and other interventions for reducing pain and improving function in patients with chronic low-back pain. Determining cost-effectiveness of care has high priority. Further research is likely to have an important impact on our confidence in the estimate of effect in relation to inert interventions and sham SMT, and data related to recovery.

Read the full abstract...
Background: 

Many therapies exist for the treatment of low-back pain including spinal manipulative therapy (SMT), which is a worldwide, extensively practiced intervention.

Objectives: 

To assess the effects of SMT for chronic low-back pain.

Search strategy: 

An updated search was conducted by an experienced librarian to June 2009 for randomised controlled trials (RCTs) in CENTRAL (The Cochrane Library 2009, issue 2), MEDLINE, EMBASE, CINAHL, PEDro, and the Index to Chiropractic Literature.  

Selection criteria: 

RCTs which examined the effectiveness of spinal manipulation or mobilisation in adults with chronic low-back pain were included. No restrictions were placed on the setting or type of pain; studies which exclusively examined sciatica were excluded. The primary outcomes were pain, functional status and perceived recovery. Secondary outcomes were return-to-work and quality of life.

Data collection and analysis: 

Two review authors independently conducted the study selection, risk of bias assessment and data extraction. GRADE was used to assess the quality of the evidence. Sensitivity analyses and investigation of heterogeneity were performed, where possible, for the meta-analyses.

Main results: 

We included 26 RCTs (total participants = 6070), nine of which had a low risk of bias. Approximately two-thirds of the included studies (N = 18) were not evaluated in the previous review. In general, there is high quality evidence that SMT has a small, statistically significant but not clinically relevant, short-term effect on pain relief (MD: -4.16, 95% CI -6.97 to -1.36) and functional status (SMD: -0.22, 95% CI -0.36 to -0.07) compared to other interventions. Sensitivity analyses confirmed the robustness of these findings. There is varying quality of evidence (ranging from low to high) that SMT has a statistically significant short-term effect on pain relief and functional status when added to another intervention. There is very low quality evidence that SMT is not statistically significantly more effective than inert interventions or sham SMT for short-term pain relief or functional status. Data were particularly sparse for recovery, return-to-work, quality of life, and costs of care. No serious complications were observed with SMT.