Prospective comparative study of intradiscal high-dose and low-dose collagenase versus chymopapain

The mixed results of two studies on intradiscal therapy with collagenase versus chymopapain are presented. The first study was performed from January 1983 to March 1984 and consisted of 71 patients treated with collagenase injection (600 ABC units) and 93 patients treated with chymopapain injection (4,000 units) into lower lumbar discs. The second study was started in May 1985 and ended December 1985. The results of 41 patients injected with chymopapain and 45 patients injected with collagenase (400 ABC units) are reported. The overall success rate after 3 months was 69%/63% for chymopapain/high-dose collagenase and 73%/71% for chymopapain/low-dose collagenase and 75%/72% after 6 months for chymopapain/high-dose collagenase. Eighteen percent of the chymopapain-treated patients and 21% of the collagenase-treated patients of the first study had to be operated on within 6 months and 12% of chymopapain patients and 29% of collagenase patients within 3 months in the second study. Six of the 134 patients who had chymopapain treatment had slight allergic reactions. Patients who had collagenase treatment had no allergic reactions under the same regimen of systemic prophylactic measures. Patients who had high-dose collagenase injections suffered significantly more from postinjectional pseudoradicular and low-back pain in the first 3 months. In the first study, no permanent neurologic complications occurred. Two patients in the low-dose collagenase group developed cauda equina syndromes in the 2 weeks after injection because of large extruded disc fragments.