Chronic nerve compression model for the double crush hypothesis.

"Double crush hypothesis" is a phrase that has entered clinical use based on a hypothesis presented by Upton and McComas in 1973. Although clinical examples of the double crush are appearing more frequently, there has been no experimental proof of this hypothesis as it relates to chronic nerve compression. This study used a model of sciatic nerve minimal banding in the rat to investigate the effect on electrophysiological function of single or double band placement, concurrently or separated in time. This study confirms that the existence of two sites of simultaneous compression, or a second (later) site of compression, placed either proximal or distal to the first (earlier) site of compression, will result in significantly poorer neural function than will a single site of compression.