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

ABSTRACT

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.