1,085 patients have been treated for intervertebral disc herniation with lombo-sciatica: in 751 cases surgical discectomy without laminectomy has been performed with or without microscope; 334 underwent papain nucleolysis. The two clinical groups were separated on clinical and radiographic backgrounds: nucleolysis was performed in patients with no motor disturbance, no stenosis of the lumbar canal, no displaced fragment; the other patients received surgical treatment. The results were evaluated according to MacNab's criteria with a follow-up of 12 to 84 months (mean 17.2 months). The results after surgical treatment were excellent in 53.8% and good in 36.8% of the cases. For papain treatment they were excellent in 32.7% and good in 38.8% of the cases. Papain nucleolysis therefore appears to be an efficient method for the treatment of intervertebral disc herniations associated with lombo-sciatica but, overall, gives poorer results than surgery in spite of a strict selection procedure. In this study, complications due to papain nucleolysis were restricted to chemical spondylodiscitis (5 cases) and to 2 benign allergic syndromes. Statistical analysis of all the cases and multifactorial correlation research pointed out the importance of "workmen's compensation" as prognostic factor. Since this study, 90% of the patients presenting with disc herniation associated with lombo-sciatica recalcitrant to medical treatment undergo surgical discectomy; papain nucleolysis is reserved for sub-ligamentary and non-displaced forms without stenosis of the lumbar canal and represent 10% of our current population.