The physiatric approach to low back pain

A Cochrane review of superficial heat or cold for low back pain

STUDY DESIGN

Cochrane systematic review.

OBJECTIVE

To assess the effects of superficial heat and cold therapy for low back pain in adults.

SUMMARY OF BACKGROUND DATA

Heat and cold are commonly used in the treatment of low back pain.

METHODS

We searched electronic databases from inception to October 2005. Two authors independently assessed inclusion, methodologic quality, and extracted data, using the criteria recommended by the Cochrane Back Review Group.

RESULTS

Nine trials involving 1,117 participants were included. In two trials of 258 participants with a mix of acute and subacute low back pain, heat wrap therapy significantly reduced pain after 5 days (weighted mean difference [WMD], 1.06; 95% confidence interval [CI], 0.68-1.45, scale range, 0-5) compared with oral placebo. One trial of 90 participants with acute low back pain found that a heated blanket significantly decreased pain immediately after application (WMD, -32.20; 95% CI, -38.69 to -25.71; scale range, 0-100). One trial of 100 participants with a mix of acute and subacute low back pain examined the additional effects of adding exercise to heat wrap and found that it reduced pain after 7 days.

CONCLUSIONS

The evidence base to support the common practice of superficial heat and cold for low back pain is limited, and there is a need for future higher-quality randomized controlled trials. There is moderate evidence in a small number of trials that heat wrap therapy provides a small short-term reduction in pain and disability in a population with a mix of acute and subacute low back pain, and that the addition of exercise further reduces pain and improves function. There is insufficient evidence to evaluate the effects of cold for low back pain and conflicting evidence for any differences between heat and cold for low back pain.

Superficial heat or cold for low back pain

BACKGROUND

Heat and cold are commonly utilised in the treatment of low-back pain by both health care professionals and people with low-back pain.

OBJECTIVES

To assess the effects of superficial heat and cold therapy for low-back pain in adults.

SEARCH STRATEGY

We searched the Cochrane Back Review Group Specialised register, the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2005), MEDLINE (1966 to October 2005), EMBASE (1980 to October 2005) and other relevant databases.

SELECTION CRITERIA

We included randomised controlled trials and non-randomised controlled trials that examined superficial heat or cold therapies in people with low-back pain.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed methodological quality and extracted data, using the criteria recommended by the Cochrane Back Review Group.

MAIN RESULTS

Nine trials involving 1117 participants were included. In two trials of 258 participants with a mix of acute and sub-acute low-back pain, heat wrap therapy significantly reduced pain after five days (weighted mean difference (WMD) 1.06, 95% confidence interval (CI) 0.68 to 1.45, scale range 0 to 5) compared to oral placebo. One trial of 90 participants with acute low-back pain found that a heated blanket significantly decreased acute low-back pain immediately after application (WMD -32.20, 95%CI -38.69 to -25.71, scale range 0 to 100). One trial of 100 participants with a mix of acute and sub-acute low-back pain examined the additional effects of adding exercise to heat wrap, and found that it reduced pain after seven days. There is insufficient evidence to evaluate the effects of cold for low-back pain, and conflicting evidence for any differences between heat and cold for low-back pain.

AUTHORS' CONCLUSIONS

The evidence base to support the common practice of superficial heat and cold for low back pain is limited and there is a need for future higher-quality randomised controlled trials. There is moderate evidence in a small number of trials that heat wrap therapy provides a small short-term reduction in pain and disability in a population with a mix of acute and sub-acute low-back pain, and that the addition of exercise further reduces pain and improves function. The evidence for the application of cold treatment to low-back pain is even more limited, with only three poor quality studies located. No conclusions can be drawn about the use of cold for low-back pain. There is conflicting evidence to determine the differences between heat and cold for low-back pain.