The purpose of the study was to evaluate whether a microsurgical discectomy (MS), compared with a standard lumbar discectomy (SD), could reduce the stay at the hospital or the postoperative morbidity. The study was prospective and of 79 patients with "virgin' lumbar radiculopathy from only one nerve root, 39 were randomized to MS and 40 to SD. All patients had positive myelography or CT findings. The fascia incision was 31 and 70 mm (p < 0.0001), respectively, but the skin incision was of the same length in both groups to blind the study. For the MS and SD group of patients, the median operation time was 48 and 35 min (p < 0.0001), and the stay at the hospital was 5.2 and 4.6 days, respectively. The two groups were not different in sex, age, localization or type of herniated discs. Use of analgesic medicine and the presence of pain in the back or legs pre- and postoperative was the same. We conclude that in a controlled and prospective study, reducing the fascia incision and the muscular dissection from a median of 70-31 mm, does not shorten the length of a stay at a hospital and it has no influence on postoperative morbidity.