Reappraisal of nerve repair

In every case of acute injury involving the nerve, the surgeon must decide whether a primary repair of an elective early secondary repair is the treatment of choice. In a clean-cut nerve without defect, immediate primary repair, using trunk-to-trunk coaptation with epineurial sutures, offers an optimal solution. In the periphery of the median and the ulnar nerves, in which motor and sensory fascicles are already separated, fascicular dissection is performed, and coaptation of fascicle groups should be done. In medical centers with excellent facilities, such nerve repair will give good results even in very severe lesions. This repair can be performed also as a delayed primary procedure. If there is a nerve defect, a primary grafting procedure must be considered. We do not recommend this as a routine procedure because the nerve grafts might be lost if a complication occurs. The decision to perform a planned early secondary repair is an equally good alternative, especially in cases of a nerve defect, severe concomitant injuries, or both. In case of a combined nerve and tendon lesion in the carpal tunnel, the nerve repair can be performed at a later procedure without exposing the repaired flexor tendons, thus avoiding adhesion between tendons and nerves. If a decision is made in favor of an early secondary repair, the two stumps can be approximated by stitches to prevent retraction, if this can be achieved without tension. Approximation under tension in case of a larger defect would damage the two stumps and create an even larger defect. Marking the nerve ends by sutures is not necessary because exploration with always start in normal tissue, exposing the nerves from the proximal or the distal segments. Early secondary repair is performed during the third week, or later if this is demanded by local conditions. When indicated, plastic surgical procedures can eliminate constricting scars and provide an optimal soft tissue environment. After exploration and preparation of the two stumps, the surgeon must decide whether direct suturing or a nerve graft is indicated. If after very limited mobilization and slight flexion the nerve stumps cannot be coapted easily, a nerve graft should be used. The quality of motor recovery decreases steadily after a 6 month delay of repair. Late secondary repairs or reoperation of failure of primary repair should be performed within this time limit, although this does not mean that motor recovery cannot occur after a longer time interval. Useful motor recovery was achieved in certain cases after 18 months or more. Obviously the results might have been better if the time interval had been shorter. If a patient is seen with a nerve lesion after a long time interval, nerve repair is still indicated if sensibility is the main functional objective. In other long-standing cases, the nerve repair is combined with tendon transfer or capsulorrhaphy. After a particularly long time interval or in old patients, only palliative surgery is indicated.