Traction for low back pain with or without sciatica: an updated systematic review within the framework of the Cochrane collaboration
STUDY DESIGN: Systematic review. OBJECTIVE: To determine if traction is more effective than reference treatments, placebo/sham traction, or no treatment for low back pain (LBP). SUMMARY OF BACKGROUND DATA: Various types of traction are used in the treatment of LBP, often in conjunction with other treatments. METHODS: We searched MEDLINE, EMBASE, and CINAHL to November 2004, and screened the latest issue of the Cochrane Library (2004, issue 4) and references in relevant reviews and our personal files. We selected randomized controlled trials (RCTs) involving any type of traction for the treatment of acute (less than 4 weeks duration), subacute (4-12 weeks), or chronic (more than 12 weeks) nonspecific LBP with or without sciatica. Sets of 2 reviewers independently performed study selection, methodological quality assessment, and data extraction. Because available studies did not provide sufficient data for statistical pooling, we performed a qualitative 'levels of evidence' analysis, systematically estimating the strength of the cumulative evidence on the difference/lack of difference observed in trial outcomes. RESULTS: A total of 24 RCTs (2177 patients) were included. There were 5 trials considered high quality. For mixed groups of patients with LBP with and without sciatica, we found: (1) strong evidence that there is no statistically significant difference in short or long-term outcomes between traction as a single treatment, (continuous or intermittent) and placebo, sham, or no treatment; (2) moderate evidence that traction as a single treatment is no more effective than other treatments; and (3) limited evidence that adding traction to a standard physiotherapy program does not result in significantly different outcomes. For LBP with sciatica, we found conflicting evidence in several of the comparisons: autotraction compared to placebo, sham, or no treatment; other forms of traction compared to other treatments; and different forms of traction. In the remaining comparisons, there were no statistically significant differences; level of evidence is moderate regarding continuous or intermittent traction compared to placebo, sham, or no treatment, and is limited regarding different forms of traction. CONCLUSION: Based on the current evidence, intermittent or continuous traction as a single treatment for LBP cannot be recommended for mixed groups of patients with LBP with and without sciatica. Neither can traction be recommended for patients with sciatica because of inconsistent results and methodological problems in most of the studies involved. However, because high-quality studies within the field are scarce, because many are underpowered, and because traction often is supplied in combination with other treatment modalities, the literature allows no firm negative conclusion that traction, in a generalized sense, is not an effective treatment for patients with LBP