The histological effect of the injection of nonsteroidal anti-inflammatory drugs on sciatic nerve of rats

Abstract

The ongoing work aims to compare the effect of extraneural and intraneural injection of therapeutic doses of meloxicam and diclofenac sodium on the sciatic nerve of rats. Six groups of adult albino rats were used with five animals per group. Control group (A), group (B), and group (C) received a single extraneural injection of normal saline (NS) 0.25 ml/kg/rat, meloxicam (M) 0.11 mg/kg/0.25ml/rat and diclofenac sodium (V) 1.1 mg/kg/0.25ml/rat respectively. In contrast, control group (D), group (E), and group (F) received a single intraneural injection of the same doses of normal saline, meloxicam, and diclofenac sodium, respectively. Histological evaluation reveals an increased thickening of epineurium, dilatation, congestion of epineurial blood vessels, intrafascicular edema, axonal degeneration, myelin degeneration, and vacuolization in group (C) which was higher than those in the group (B). These changes were also greater in group (F) compared to groups (D) and (E). The histopathological changes of the sciatic nerve were greatest in the case of intraneural injection of saline, meloxicam, and diclofenac sodium, which means that the damaging effect of intraneural injection of the drug was greater than the extraneural injection of the same drug. It is concluded that extraneural and intraneural injections of therapeutic doses of meloxicam cause less damage to the sciatic nerve compared to diclofenac sodium. Thus it is considered to be more secure than diclofenac sodium after intramuscular injection. Sciatic nerve injury can occur following intramuscular injection into the gluteal region, particularly if the needle hits the nerve.