In paraplegics who can benefit from bilateral microsurgical L2-S1 drezotomy for the treatment of harmful spasticity involving the two lower limbs, surgery can be extended to the segments S2-S4 for the treatment of an associated hyperactive bladder. The surgery in the dorsal root entry zone (DREZ) is designed to preferentially interrupt nociceptive and myotatic inputs from the detrusor muscle reaching the sacral spinal segments S2, S3, S4. This work reports a prospective study of 38 patients who underwent bilateral S2, S3, S4 drezotomy with a follow-up of 18 months on average. All these patients were unable to have voluntary miction and had sexual dysfunctions. Urge incontinence was present in all of them. A hyperactive bladder was present at the preoperative urodynamic study in all patients. A vesico-ureteral reflux was demonstrated in 13 cases (34%) during cystography. A postoperative urodynamic study was performed at 6 months on average and demonstrated disappearance of hyperactivity of the detrusor muscle in 82% of the cases and increased bladder capacity in 63%, corresponding to patients without a preoperative fibrotic detrusor. They were no cases of postoperative vesico-ureteral reflux at cystography. At 18 months, the urine leakages have disappeared in 89% and decreased to less than half per day in the other 11%. As expected, all the patients required postoperative permanent or intermittent catheterization. The morbidity was acceptable in these severely impaired patients. To conclude, a bilateral sacral (S2-S4) microsurgical drezotomy can be performed in addition to a lumbosacral drezotomy to treat an active bladder associated with harmful spasticity in both legs. The sacral microsurgical drezotomy allows to achieve bladder continence and to protect the upper urinary tract