Ultrasound-Guided Atelocollagen Injection for Chronic Pain After Spinal Surgery: A Retrospective Cohort Study

Area of Science:

• Regenerative Medicine
• Pain Management
• Spinal Surgery

Background:

• Chronic pain after spinal surgery (CPSS), previously known as failed back surgery syndrome (FBSS), is challenging to treat.
• Paraspinal muscle degeneration is increasingly recognized as a factor in CPSS.
• Injectable type I porcine atelocollagen is being explored for its potential in managing CPSS due to its anti-adhesive and regenerative properties.

Purpose of the Study:

• To evaluate the efficacy of ultrasound-guided atelocollagen injections into paraspinal muscles for CPSS patients.
• To identify potential predictors of treatment response in CPSS patients receiving atelocollagen injections.

Main Methods:

• A retrospective cohort study of 34 adult CPSS patients receiving ultrasound-guided atelocollagen injections into paraspinal muscles.
• Pain intensity was measured using the 11-point numeric rating scale (NRS) at baseline and 3 months post-injection.
• A composite outcome was defined as a ≥1-point NRS reduction or a Patient Global Impression of Change (PGIC) score of 4 or 5.

Main Results:

• Atelocollagen injection resulted in a significant mean NRS score decrease of 1.62 points at 3 months (p<0.001).
• No significant predictive factors for a positive composite outcome were identified through logistic regression.
• A higher proportion of non-responders were taking anticonvulsants or antidepressants compared to responders (100% vs 54.2%, p=0.028).

Conclusions:

• Ultrasound-guided atelocollagen injection into paraspinal muscles demonstrated an association with pain reduction in CPSS patients.
• The findings suggest atelocollagen may serve as an adjunctive or investigational treatment for CPSS.
• The lack of a control group limits definitive causal interpretation, highlighting the need for further research.