Upper urinary tract complications have been reported in about 20-30% of spinal cord injury patients. Their pathogenesis is linked to the presence of high-pressure uninhibited detrusor contractions, high leak point pressure and low bladder compliance. The aim of this study was to evaluate the incidence of upper urinary tract complications in two homogeneous groups of spinal cord injury patients with different bladder emptying modalities (intermittent catheterization vs. tapping, abdominal straining, Crede's manoeuvre) and the relationship with clinic and urodynamic features. A total of 17 patients (22%) had upper urinary tract complications. The incidence of both urinary tract dilatation and vesicoureteral reflux was significantly lower in patients having intermittent catheterization (P = 0.03 and 0.04 respectively). Intermittent catheterization thus seems to be effective in preventing upper urinary tract disease in spinal cord injury patients requiring mechanical bladder emptying modalities. The finding of upper urinary tract complications also in patients having intermittent catheterization showing high intravesical pressures stresses the need of adding anticholinergic medications to the rehabilitation regimen of these patients.