Chemonucleolysis of lumbar intervertebral disc prolapse with chymopapain: outcome after 1 year.

One hundred and one consecutive patients with lumbar disc prolapse were treated by chymopapain chemonucleolysis and their response and favourable pre-treatment criteria determined. Most improvement occurred within the first month, and one year after treatment outcome was judged satisfactory (excellent or good) in 71%. Individual patient characteristics associated with a satisfactory response were sciatica of greater severity than back pain (p = 0.005) and duration of symptoms less than 18 months (p = 0.03). Patients fulfilling 3 or 4 of four immediate pre-treatment clinical and radiographic criteria (sciatica more severe than back pain, reduced straight leg raising, neurological deficit, radiographic abnormality) had a satisfactory response more often than others (p less than 0.05). Reported success one year after surgery for disc prolapse is similar. Chemonucleolysis, however, requires less resources and does not preclude subsequent operation. Our results therefore suggest that it might be considered an alternative to surgery when conservative treatment has failed.