Heat wrap therapy reduces pain and disability in early stage low back pain

Abstract

Is superficial heat or cold therapy effective in the management of low back pain? Trials were located by searches of Medline, Embase, CINAHL, PEDro, Sportdiscus, OldMedline, Cochrane Back Review Group Specialised Register and Cochrane Central Register of Controlled Trials, as well as screening reference lists in relevant articles. Randomised and non-randomised controlled trials that examined superficial heat or cold in adults with non-specific low back pain (LBP) of any duration were eligible for inclusion. Trials comparing various modes of heat or cold therapy to placebo, no therapy, or other therapies were eligible. Methodological quality of included trials was assessed using the Cochrane Back Review group criteria. Trials were eligible if they included at least one of the following outcomes: pain, disability/function, overall improvement, patient satisfaction, and adverse effects. Results were expressed as weighted mean differences (WMD) with 95% confidence intervals. The literature revealed 1178 potentially eligible studies, but only nine fulfilled the eligibility criteria. Pooled data from two trials (Nadler 2003a & b) of 258 participants with a mix of acute and subacute LBP showed heat wrap therapy reduced pain (WMD = −1.06, −1.45 to −0.68, scale range 0 to 5) and disability (WMD = −2.10, −3.19 to −1.01, scale range 0 to 24) after 5 days compared with oral placebo. In one trial of acute LBP (Nuhr 2004) a heated blanket resulted in a moderate short-term reduction in pain (WMD = −32.20, −38.69 to −25.71, scale range 0 to 100) compared with a non-heated blanket when measured immediately after application. One high quality trial (Mayer 2005) of acute and subacute LBP subjects investigated whether exercise with heat wrap therapy was more beneficial than exercise alone. The addition of heat wrap resulted in moderate improvements in pain (WMD = −1.40, −2.11 to −0.69, scale range 0 to 5) and function (WMD = −3.20, −5.42 to −0.98, scale range 0 to 24) at day 7, but not earlier. Longer term effects of these interventions are unknown. No controlled trials were located that examined the effects of heat on pain or disability for chronic LBP. There is insufficient evidence to evaluate the effects of cold for LBP. There is moderate evidence that heat wrap therapy results in small, short-term reductions in pain and disability in LBP of up to 12 weeks duration, and that the addition of exercise may provide further benefit.