It is now well known that after reunion of a divided nerve by means of suture, function may return sooner or later, and that not only does this restoration of function imply simple return of sensation and of the capacity of making voluntary movements, but the re-establishment of complete localisation of sensation and of co-ordination of movements. When it is remembered that the individual nerve fibres are supposed to be paths between well-defined centres and peripheral endings, it is clear that so perfect a restoration of function is in many respects remarkable. Thus, in coapting a divided nerve, it is not likely that this can be effected with so great accuracy, that the corresponding ends of the divided nerve fibres can be brought into apposition. It is more likely that in coapting the nerve, most of the ends of the nerve fibres which are brought into contact are ends which do not correspond; and thus it would be expected that in the reunited nerve new paths for the nervous impulses would be established. And yet, despite this complexity of structure and of function, the reunited nerve seems to be as capable as before the division of subserving its functions.

In suturing divided nerves, care is usually given to secure that the two segments are approximated as nearly as possible in their old relationship. Thus, the perfect recovery of localised and co-ordinated function might be due to a majority of the fibres being thus placed in a position for union as before the division to take place.