Sixty-one patients who had lumbar instability and chronic low back pain or
deformity from nontraumatic lumbar pathologies were studied. In all of them a
posterior lumbosacral fusion with CUN (Clinic of the University of Navarre)
pedicle rod fixation was used. The mean follow-up period was 36 months (range
26-46 months). The consolidation rate was evaluated according to plain and
functional radiographs, and a clinical evaluation was made using an analogue pain
scale. The rate of fusion was 93.5%. Neurological complications occurred in 3.3%.
The incidence of screw failure was 2.3% of all the screws. No other implant
failure occurred. The patients rated their clinical results as 'excellent' in
33.8% of the cases, 'good' in 42.2%, 'fair' in 16.9% and 'poor' in 6.7%. CUN
instrumentation is a versatile internal fixation system that has been shown to
provide satisfactory stability. Furthermore, the clinical results are comparable
to those reported in studies in which the most common hardwares were used
