Traction Definition of the procedure Lumbar traction is applied by putting a harness around thelower rib cage and a second one around the iliac crest, andapplying a force aiming at separating both harnesses. Theapplied force must be at least 25% of the body weight(weaker forces are considered as placebo). The durationand level of exerted traction can be varied in a continuousor intermittent mode (van der Heijden et al 1995). Different types of traction exist: manual traction (i.e.traction exerted by the therapist, using the patients head,arms or legs), motorised traction (i.e. traction exerted by amotorised pulley), suspension (i.e. traction exerted bygravitational forces, through the body weight of the pa-tient), and bed-rest traction (i.e. traction by a pulley andweights) (van der Heijden et al 1995). Systematic reviews One systematic review (SR) was found (van der Heijden etal 1995) . Among the 17 RCTs included in the review, 16 wereexcluded for the following reasons: 3 focused on cervical traction (British 1966, Goldie andLandquist 1970, Zylbergold and Piper 1985) 5 included only acute low back pain patients (Coxheadet al 1981, Larsson et al 1980, Mathews et al 1987, Palet al 1986, Walker et al 1982) 2 did not provide information on the duration ofpain (Mathews and Hickling 1975, Reust et al 1988) 4 focused specifically on prolapsed lumbar disk, and noton common low back pain (Ljunggren et al 1984, Weber1972, 1973, Weber et al 1984) 1 used only global treatment effect as the outcomemeasure (Bihaug 1978) 1 examined combination treatments (intermittent motor-ized traction and isometric abdominal exercises vs hotpacks and rest vs hot packs, massage and mobilisation)and also used only global treatment effect as the out-come measure (Lidstrom and Zachrisson 1970) The remaining RCT were used as the basis for formulatingthese recommendations (van der Heijden et al 1970). Additional trials No additional trials were found. Quality assessment of the evidence The systematic review was of high quality. The one rele-vant RCT on CLBP that it included was of high quali-ty (van der Heijden et al 1970). Effectiveness The RCT compared motorized traction with sham tractionand did not find any significant differences between thetreatments for any of the outcome measures exam-ined (van der Heijden et al 1970). There is limited evidence that lumbar traction is notmore effective than sham traction (level C). Unknown (no studies were found on this issue) There is no evidence for the effectiveness of lumbartraction compared with other treatments in the treatment ofchronic low back pain (level D). Cost/effectiveness Unknown (no studies were found on this issue) Safety The SR did not review studies on safety of lumbar trac-tion, but cited case reports suggesting that there is dangerof adverse effects in heavy traction (lumbar traction withforces exceeding 50% of the total body weight) (van denHoogen et al 1995). Those risks include increased bloodpressure and respiratory constraints due to the traction har-ness, and a theoretical potential increase of nerve impinge-ment in cases of medial or distal disk protrusion. Subjects (indications) Not having shown evidence of effectiveness, it is not pos-sible to define indications for lumbar traction. Comments None Summary of evidenceThere is limited evidence