Does the use of the operating microscope improve the results of peripheral nerve suture?

Twenty-four cases of complete division of median or ulnar nerves were assessed on two occasions after direct suture, with an interval of three years between assessments. Clinical, electrophysiological and timed functional tests were used. All the operations had been performed by one surgeon, using the operating microscope for approximately half the cases but not for the other half. The results were analysed, and the patient's age, any delay between injury and suture, and the duration of follow-up were all found to exert strong and consistent effects on the scores obtained. After controlling for these factors, there was no consistent difference between the results of the two surgical methods. It is concluded that, at least in the hands of one particular surgeon, the use of the operating microscope gives no better results than careful epineural suture performed without it.