Research Review by Dr. Shawn Thistle©
Study Title:Cochrane review investigates the use of heat and cold for the treatment of low back pain
Authors:French SD et al.
Publication Information:Spine 2006; 31(9): 998-1006.
Summary:Low back pain remains a common and disabling problem. Superficial heat or ice are common prescriptions in a variety of healthcare environments to relieve the symptoms of low back pain. Although normally not offered as stand-alone treatments, ice and heat are often added as a homecare component to a treatment plan.
Traditionally, ice has been recommended for acute injury and heat for more chronic problems (although it is not hard to find differing opinions on this matter). Superficial heat methods include hot water bottles, heated stones, soft heated packs, poultices, hot towels, hot baths, saunas, heat wraps, electric heat pads, and infra-red heat lamps.
These methods seem to be best at heating superficial tissues not more than ~ 0.5 cm from the surface of the skin. Deep heating can be achieved with modalities such as ultrasound or short wave diathermy, but these treatment options were not included in this review. Superficial cold applications can include ice packs, cold towels, ice massage, or gel packs.
Treatment guidelines for lower back pain have given different recommendations regarding the application and benefits of heat and cold. Therefore, the aim of this Cochrane Review was to assess the effects of superficial heat or cold for low back pain in adults.
Randomized and non-randomized controlled trials comparing superficial hot or cold therapy to placebo, no therapy, or other therapies were included. The literature search strategy and selection of studies were done in accordance with the Cochrane Back Review Group. The literature search resulted in 1178 potentially eligible studies.
After applying the inclusion criteria, 9 studies involving 1117 patients were deemed suitable. Of these 9 trials, only 4 contained data that could be extracted and utilized in a meta-analysis. The studies in total included patients with acute (< 6 weeks), subacute (>6-<12 weeks) and chronic (> 12 weeks) low back pain patients.
- there is a general lack of quality studies in this area, and pooling of the data was generally not possible
- industry sponsored studies are more likely to report a positive outcome
- there is moderate evidence that a heat wrap applied for 8 hours or an electric blanket applied for 25 minutes are more effective than no heat for acute or subacute low back pain in the short term (4 days)
- there is moderate evidence that combining a heat wrap and McKenzie exercises is better for pain relief and function after 7 days than an educational booklet and either a heat wrap or the exercises alone
- no conclusion can be drawn for the efficacy of cold application for low back pain, as only 3 poorly designed studies identified
- there is insufficient evidence about the effects of heat for back pain that has lasted longer than three months
Conclusions & Practical Application:Heat and cold are commonly recommended by clinicians for low back pain. It was surprising to me to find out that the evidence to support this common practice is not strong.
Overall, there is conflicting evidence when looking at the differences between heat and cold. From a clinical and physiological perspective, consideration should be given to the treatment techniques being used on a patient (manual therapy, acupuncture, electromodalities etc.) when deciding to recommend heat or cold.
In my clinical experience, most people will choose whichever one feels better, is more convenient, or has worked for them in the past. Based on the evidence presented in this review, perhaps that is not a detrimental approach.
Current evidence suggests early activation for low back pain patients is crucial to avoid the development of chronic disability and pain. Whether heat OR cold allows patients to maintain normal activities and self-mange their pain, clinicians should encourage this behaviour in conjunction with the other treatments we offer.