Effects of diclofenac and ketoprofen on nerve conduction velocity in experimental nerve root compression

Study Design. The effects of diclofenac and ketoprofen on nerve conduction velocity in experimental nerve root compression were evaluated in a setup using an established pig model. Objective. To assess the effects of two potent nonsteroidal antiinflammatory drugs, diclofenac and ketoprofen, in experimental nerve root compression. Summary of Background Data. Compression of spinal nerve roots is recognized to be of major etiologic importance for several common spinal pain syndromes. Secondary inflammatory changes, induced by microvascular permeability changes and leakage of inflammatory mediators into the endoneural tissue, have been proposed as important for the induction of spinal nerve root injury by chronic compression. Methods. This study involved 21 pigs. An ameroid constrictor was used to induce compression. Seven pigs were treated with daily intramuscular injections of diclofenac 3 mg/kg for 7 days. Seven other pigs were treated with daily intramuscular injections of ketoprofen 4 mg/kg. For a control, seven pigs did not receive any drug treatment. After 7 days, the pigs were reanesthetized , and the nerve conduction velocity in the compressed nerve root segments was determined. Results. The nerve conduction velocity was significantly higher (P < 0.05, Student's t test) in the pigs treated with diclofenac (50 +/- 16 m/second) than in the untreated pigs (32 +/- 15 m/second). The nerve conduction velocity also was significantly higher (P < 0.05) in the pigs treated with ketoprofen (59 t 16 m/second) than in the untreated pigs. There were no significant differences in nerve conduction velocity between pigs treated with ketoprofen and those treated with diclofenac. Conclusions. The findings indicate that intramuscular administration of diclofenac or ketoprofen, both potent antiinflammatory drugs, may reduce nerve root dysfunction induced by compression of spinal nerve roots in an experimental pig model.