Preventative effect of diclofenac sodium and/or diltiazem in rats with epidural fibrosis

Spinal epidural fibrosis is commonly seen after laminectomy. There is not yet proven any agent preventing fibrosis in clinical usage. We used diclofenac sodium and diltiazem, which are fibrosis inhibitors.

40 rats were divided into four groups of equal numbers: control, diclofenac sodium, diltiazem, and diclofenac sodium + diltiazem. Laminectomies were performed at L5 and L6. After a 4 week period, the rats were decapitated and the vertebral column blocks were removed for histopathologic examination. Fibrosis percentage, spread of fibrous regions, and fibroblast numbers were evaluated in each group and compared between the groups.

The distribution of epidural fibrosis density, percentage of fibrosis, and distribution of fibroblasts in the diclofenac sodium + diltiazem group were significantly lower than in the other groups. The fibroblast numbers of the diltiazem, and diclofenac sodium + diltiazem groups were significantly lower than in the other groups.

Diclofenac sodium + diltiazem used together provided better outcomes because each of them prevented fibrosis via different ways, probably through synergistic action (Tab. 5, Fig. 3, Ref. 43).