Low back pain (LBP) poses a significant problem to society. Although initial
conservative therapy may be beneficial, persisting chronic LBP still frequently leads to expensive invasive intervention. A novel non-invasive
therapy that focuses on discogenic LBP is Intervertebral Differential Dynamics
Therapy (IDD
Therapy, North American Medical Corp. Reg U.S.). IDD
Therapy consists of intermittent
traction sessions in the Accu-SPINA device (Steadfast Corporation Ltd, Essex, UK), an FDA approved, class II medical device. The intervertebral disc and facet joints are unloaded through axial distraction, positioning and relaxation cycles. The purpose of this study is to investigate the effect of IDD
Therapy when added to a standard graded activity program for chronic LBP patients. In a single blind, single centre, randomized controlled trial; 60 consecutive patients were assigned to either the
SHAM or the IDD
Therapy. All subjects received the standard conservative therapeutic care (graded activity) and 20 sessions in the Accu-SPINA device. The
traction weight in the IDD
Therapy was systematically increased until 50% of a person's
body weight plus 4.45 kg (10 lb) was reached. The
SHAM group received a non-therapeutic
traction weight of 4.45 kg in all sessions. The main outcome was assessed using a 100-mm visual analogue scale (VAS) for LBP. Secondary outcomes were VAS scores for leg
pain, Oswestry Disability Index (ODI), Short-Form 36 (SF-36). All parameters were measured before and 2, 6 and 14 weeks after start of the treatment. Fear of (
re)injury due to movement or activities (Tampa Scale for
Kinesiophobia), coping strategies (Utrecht Coping List) and use of
pain medication were recorded before and at 14 weeks. A repeated measures analysis was performed. The two groups were comparable at baseline in terms of demographic, clinical and psychological characteristics, indicating that the random allocation had succeeded. VAS
low back pain improved significantly from 61 (+/-25) to 32 (+/-27) with the IDD protocol and 53 (+/-26) to 36 (+/-27) in the
SHAM protocol. Moreover, leg
pain, ODI and SF-36 scores improved significantly but in both groups. The use of
pain medication decreased significantly, whereas scores for
kinesiophobia and coping remained at the same non-pathological level. None of the parameters showed a difference between both protocols. Both treatment regimes had a significant beneficial effect on LBP, leg
pain, functional status and quality of life after 14 weeks. The added axial, intermittent, mechanical
traction of IDD
Therapy to a standard graded activity program has been shown not to be effective.