We report a consecutive series of 200 patients who underwent Dynesys flexible stabilisation in the management of intractable lower back pain.
Methods: Patients were only accepted for the study if exhaustive conservative management had failed. They underwent operation between September 2000 and March 2003. Patients were divided into two groups:
Group 1 - Cases where implantation was used as an adjunct to other procedures including decompression, discectomy, or posterior lumbar interbody fusion. (32 male, 36 female, Mean age 56years (range 31–85)).
Group 2 - Patients with back pain and/or sciatica in which no other procedure was used. (65 male 67 female, Mean age 58years (range 27–86))
All patients were profiled prospectively using the Oswestry Disability Index (ODI), SF36 and Visual Analogue Scale (VAS). Patients were reviewed post-operatively using the same measures at 3, 6 &
12 months, and yearly thereafter. Follow-up was 95% at 2 to 5 years.
Results: Group 1 – Mean ODI fell from 54 pre-op to 24 at four years
Group 2 – Mean ODI fell from 49 pre-op to 28 at four years
Similar trends were observed in both groups with a fall in VAS and improvement in SF36.
Discussion: Indications can only be defined following clinical outcome. Perceived indications were based on contemporary understanding of the biomechanical effects of the construct. Further investigation of these variables is clearly desirable. Screw failures (15%) have detracted from the overall success. The virtue of flexible stabilisation over fusion includes avoidance of domino effect, reversibility and possible healing of a painful segment. The key issue is whether it is as effective and this requires prospective randomised controlled investigation, both against fusion, and conservative management. We feel our results in this difficult group of patients are reasonable and continue to use it in our practice.