Epidural adhesions after chymopapain chemonucleolysis.

Epidural adhesions were discovered in seven of nine patients undergoing surgery for failed chymopapain chemonucleolysis. Clinically the adhesions were very vascular, prolific and adherent to the nerve root, dura and the porieties. The histological composition was similar to the normal tissues of the epidural space from the post-mortem controls and also to adhesions discovered at surgery in a non-injected patient, except that there was an increase in fibrous tissue, which was poorly cellular. There was no evidence of an inflammatory infiltrate. Such adhesions may partly explain the failure of chemonucleolysis and prejudice the success of surgery by potentiating further adhesion formation.