Factors associated with disc degeneration based on Pfirrmann criteria after condoliase treatment for lumbar disc herniation.

BACKGROUND

Lumbar disc herniation (LDH) is a common cause of low back pain and is associated with degeneration of the nucleus pulposus causing nerve root compression. Chemonucleolysis of the nucleus pulposus with condoliase is a low-invasive treatment for LDH. The purpose of this study was to investigate changes in Pfirrmann criteria, which are used to evaluate disc degeneration, after injection of condoliase into a herniated intervertebral disc, and to identify factors associated with disc degeneration at 3 months post-injection.

METHODS

Medical records and radiographic findings were reviewed retrospectively for 127 patients with LDH (88 male, 39 female, mean age: 46.6 ± 17.1 years, mean follow-up: 9.8 ± 7.8 months) who underwent chemonucleolysis with intradiscal condoliase injection at our center since September 2018. Condoliase (1.25 U/mL; 1 mL volume) was injected toward the middle of the affected intervertebral nucleus pulposus using a 21-gauge disc-puncture needle.

RESULTS

Cases in which the Pfirrmann grade did and did not progress in the 3 months after the injection were included in groups P (progression, n = 49) and NP (non-progression, n = 78), respectively. Logistic regression analysis of progression of Pfirrmann grade post-injection showed significant associations with age <40 years (p = 0.013, odds ratio (OR): 3.69, 95% confidence interval (CI): 1.32-10.31), Pfirrmann Grade II or III at baseline (p = 0.021, OR: 3.51, 95% CI: 1.24-9.64), and a high-intensity MRI signal in the herniation (p = 0.047, OR: 2.97, 95% CI: 1.03-8.87). Patients in group P had significantly higher rates of disc height decrease ≥20%, reduced herniated disc size, and improved VAS for pain, but both groups had significant decreases in pain. No cases had anaphylactic shock or neurologic sequelae.

CONCLUSIONS

These results show the safety and efficacy of chemonucleolysis with condoliase for treatment of painful LDH. Progression of Pfirrmann criteria on MRI at 3 months after injection was significantly associated with an improved clinical outcome.