Certain fundamental principles in the treatment of peripheral nerve injuries deserve re-emphasis from time to time. It has become a trite thing, but it is true that in the excitement connected with the immediate repair of a lacerated extremity tendons are mistaken for nerves and nerves are mistaken for arteries. The result is that a nerve may be sutured to a tendon or, even more frequently, a severance of the nerve trunk may not be recognized at all.
Early recognition of a peripheral nerve injury is the greatest single prophylactic measure that can be taken to insure a good result after surgical repair of an interruption in the continuity of a nerve trunk. Lesions of the median, ulnar, and radial nerves are the commonest of the injuries to the peripheral nerves in the upper extremities, and to these injuries must be added injuries of the brachial plexus. In general, it