Growth factor-loaded scaffolds for locomotor recovery after traumatic spinal cord injuries: a meta-analysis of preclinical evidence.

STUDY

DESIGN

Systematic review and meta-analysis of preclinical studies.

PURPOSE: To evaluate the efficacy of biomaterial scaffolds incorporating neurotrophic growth factors in promoting locomotor recovery after traumatic spinal cord injury (SCI).

OVERVIEW OF LITERATURE: SCI results in severe neurological deficits and limited regenerative capacity. Biomaterial scaffolds provide structural support and, when combined with neurotrophic growth factors, may enhance axonal regeneration and functional recovery. However, despite numerous preclinical studies, the pooled efficacy of these strategies has not been comprehensively quantified.

METHODS

Comprehensive searches of Medline, Embase, Scopus, and Web of Science were conducted through May 2025. Two independent researchers conducted the screening process and extracted data as per the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. Eligible studies assessed functional recovery in rodent SCI models treated with scaffolds containing neurotrophic factors. A random-effects meta-analysis was performed to calculate standardized mean differences (SMDs) and 95% confidence intervals (95% CI). Risk of bias (ROB) was evaluated using SYRCLE's ROB tool. The certainty of evidence was reported using the GRADE framework.

RESULTS

Analysis of 56 articles revealed that brain-derived neurotrophic factor (BDNF) (SMD, 3.35; 95% CI, 1.71-5.00; p <0.001), nerve growth factor (NGF) (SMD, 4.51; 95% CI, 1.57-7.45; p <0.001), neurotrophin-3 (NT-3) (SMD, 2.57; 95% CI, 1.29-3.84; p <0.001), basic fibroblast growth factor (bFGF) (SMD, 3.23; 95% CI, 1.84-4.62; p <0.001), and insulin-like growth factor 1 (IGF-1) (SMD, 2.39; 95% CI, 1.35-3.43; p <0.001) were associated with significant improvements in locomotion. NGF demonstrated sex-specific differences favoring females (p =0.026), while bFGF was most effective in transection models (SMD, 4.60; p <0.001). Both bioactive and non-bioactive scaffolds effectively delivered BDNF and NGF.

CONCLUSIONS

Growth factor-loaded scaffolds, especially those incorporating BDNF, NGF, and NT-3, demonstrate substantial potential for the treatment of SCI. These findings highlight the significance of selecting appropriate scaffold materials and delivery strategies tailored to specific injury types.