The effects of Epidermal Growth Factor (EGF) on axonal regeneration of a sectioned sciatic nerve within collagen tubes were investigated in 15 rats. Following baseline electrophysiologic assessment, bilateral 7-mm nerve gaps were created and repaired by interposition of collagen tubes, into which EGF (left side) or type I collagen (right side) was instilled. After 4 or 8 weeks, axonal regeneration, measured by electrophysiologic and histologic means, was identical for the EGF and control legs. The conclusion is that EGF does not influence nerve regeneration within a collagen chamber.