Nucleus pulposus regeneration after chemonucleolysis with chymopapain?

Area of Science:

• Orthopedics
• Biochemistry
• Histopathology

Background:

• Chemonucleolysis is a minimally invasive treatment for herniated lumbar discs.
• Enzyme activity in disc tissue after chemonucleolysis requires further histological investigation.
• Understanding enzyme effects is crucial for evaluating treatment efficacy and patient outcomes.

Purpose of the Study:

• To histologically verify the enzymatic activity of chymopapain in patients with herniated lumbar discs who underwent surgery after failed chemonucleolysis.
• To correlate histological findings with the time interval between chemonucleolysis and surgery.
• To assess the regenerative potential of the nucleus pulposus.

Main Methods:

• Light microscopy with hematoxylin and eosin, van Gieson's, Nissl's, and periodic acid-Schiff staining was used.
• Disc material from 88 patients who failed chemonucleolysis and underwent surgery was analyzed.
• Histologic alterations indicating enzymatic activity were quantified and compared to a control group.

Main Results:

• Histologic signs of enzymatic activity were observed in 84 out of 88 analyzed disc samples.
• Eosinophilia of the ground substance, altered Nissl staining, and positive periodic acid-Schiff reaction in chondrocyte halos indicated enzyme activity.
• Enzymatic activity signs were significantly stronger (P < 0.01) in samples with shorter intervals between chemonucleolysis and surgery.

Conclusions:

• The histological findings confirm the in vivo activity of the enzyme used in chemonucleolysis.
• Shorter intervals between chemonucleolysis and surgery correlate with more pronounced enzymatic activity.
• The results suggest a potential regenerative capacity of the nucleus pulposus following chemonucleolysis.