Peripheral nerve injuries often lead to incomplete recovery despite surgical repair. Vitamin B12 and folic acid have been implicated in nerve regeneration, but their comparative effects have not been systematically evaluated. Twenty-four male Wistar rats underwent femoral nerve transection and were assigned to three groups: control, vitamin B12 (2500 µg/kg weekly, subcutaneous), and folic acid (40 mg/L in drinking water). Functional recovery was assessed over eight weeks using foot-base angle (FBA) during beam walking. Histological analysis evaluated axon counts and myelination (g-ratio). Both treatments accelerated early gait recovery compared to controls, with significant FBA improvement at week 4 (p < 0.05). Vitamin B12 produced sustained functional benefits through week 8 and superior myelination (lower g-ratio, p < 0.0001), whereas folic acid increased axon numbers but did not enhance myelin thickness or late-phase recovery. High-dose vitamin B12 significantly improves structural and functional outcomes after femoral nerve injury, while folic acid primarily supports early axonal regrowth. Vitamin B12 represents a promising pharmacological adjunct for peripheral nerve repair. Further research should explore optimal dosing strategies and long-term effects in clinical settings. To our knowledge, no prior study has directly compared the effects of folic acid and vitamin B12 supplementation within the rat femoral-nerve model, providing the rationale for the present head-to-head design.
Basailović et al. (Mon,) studied this question.