There is a rather uniform opinion that under conditions of warfare secondary nerve suture gives the best return of motor and sensory function.

In civilian life, where the types of trauma and the availability of medical care differ from those in warfare, there is difference of opinion as to whether primary or early secondary nerve suture gives the best functional result.

This investigation was, therefore, planned to compare the results of primary and early secondary nerve suture after types of trauma common in civilian life. Electromyographic recordings of voluntary action potentials in the reinnervated muscle were used to compare the two groups.

Under unsterile conditions, thirty median and thirty ulnar nerves were sharply cut or bluntly divided at the wrist in rhesus monkeys. These nerves were then sutured primarily about four hours after nerve injury, or the skin was closed about four hours after injury and the nerves sutured secondarily about three weeks after injury.

Serial electromyograms were obtained. By nine months, there was little or no increase in the number of voluntary action potentials in the muscles tested so that the data at nine months were used for comparison of the primary and secondary nerve repairs.

The findings indicated that the nerves primarily sutured following the types of trauma commonly seen in civilian life provided a definitely higher grade of motor reinnrvation of the intrinsic muscles of the hand than did the secondarily sutured nerves. All thirty primarily sutured nerves were given grades of A or B; twenty-seven of the secondarily sutured nerves were graded C; two were graded B, and one rated D (Table II). In these experiments, the type of trauma (Sharp or blunt) did not influence the result after either primary or secondary suture.

To verify that there was a correlation betweens the electromyographic examination and functional motor return following nerve suture, these two methods of evaluation were carried out in human patients after median and ulnar nerve suture. Statistical analysis showed that there was a reasonably strong positive correlation between the results of the two methods of evaluation.