Fig. 6: Electrophysiology change pattern of brachial plexus after CC7 transfer evaluated by multisite optogenetic stimulation method.

a A schematic diagram of CC7 transfer surgery. Upper trunks and lower trunks were marked yellow. Middle Trunks of healthy side and impaired side were marked cyan and green, respectively. The implantation positions of the MOSD II were pointed by blue arrows. b Schematic of the strategy of CMAP experiments by MOSD II. MOSD II was wrapped around the transferred C7 nerve and fixed on the distal (green) of nerve anastomosis by microsutures. Different nerve fascicles were illustrated in different colors. c Timeline of CMAP and induced-behavioral experiments after TBI and CC7 transfer. CMAP curve of forearm extensors, forearm flexors, biceps brachii and triceps brachii induced by spatially selective optogenetic stimulation of regenerating middle trunks (d), lower trunks (e) and upper trunks (f). CMAP curves from each mouse in TBI + CC7 groups (mice undergoing TBI and CC7 surgery) at 4, 8, and 12 weeks after surgery and TBI groups at 12 weeks after surgery were presented. g The heatmap of CMAP area from different mice groups and weighted analysis of brachial plexus innervation to four muscle groups on the affected limb. n = 6 for control and TBI 12w group, n = 10 for TBI + CC7 4w group, n = 9 for TBI + CC7 8w group, n = 13 for TBI + CC7 12w group.