A microruler for microsurgery

Turnover epineural sheath tube in primary repair of peripheral nerves

The epineural repair technique, which is the gold standard of peripheral nerve injuries, is still far from being ideal. The purpose of this study was to investigate the effects of the turnover epineural sheath tube (TEST) when used over the primary nerve repair site to improve nerve regeneration. Twenty-five Wistar rats were divided into three groups and were operated. In the sham control group, the sciatic nerve was dissected from the sciatic notch to its bifurcation and was left intact. In the primary epineural repair group an incision was made on the nerve and it was repaired using six epineural sutures. In the TEST group, after the incision was made the nerve ends were approximated with two epineural sutures. A proximal circular epineural incision was then made to enable the epineurium to be turned and slid over the repair site. Functional recovery was evaluated by walking tract analysis, and the sciatic functional index was calculated. Histomorphometric studies of the sciatic nerves and gastrocnemius muscles were also performed 3 months postoperatively. Three months postoperatively, functional analysis and nerve and muscle histomorphometric studies revealed similar results in the primary repair and TEST groups. There was no significant difference (p > 0.05) between the results of the TEST and the primary nerve repair groups. However, during the microscopic examination, a decrease in both foreign material reaction and an inflammatory response with less fibrosis were observed in the TEST group. The TEST has a nerve-healing property similar to primary epineural repair, with the advantage of a reduced number of sutures, which decreases the fibrosis around the repair site. The TEST is an alternative treatment modality among other techniques, especially for polyfascicular peripheral nerves.