Abstract: To evaluate the forward therapeutic effect of chemonucleolysis using collagenase for the treatment of lumbar intervertebral disc protrusion, a follow up survey of 32 cases was made. All the patients were hospitalized and treated with this method. Of the cases, 15 were treated with :“intradisc injection method”, i. e. the injection with 400～600 U of the enzyme was given into the intervertebral disc and 17 with extradisc injection method, i. e. the injection with 600～1200 U of the enzyme was given into the extradural space. Results: 17 showed excellent results, 2 good, 6 fair and 7 poor. Totally, the injection treatment of collagenase gave an excellent and good rate of 59.4%, and an effective rate of 78.1%. The surgical exploration rate was 12.5%.

Key words: lumber intervertebral disc protrusion, collagenase, chemonucleolysis, intradisc injection, extradisc injection