DOI: 10.34944/dspace/9955
title: Nerve transfer for restoration of lower motor neuron-lesioned bladder, urethral and anal sphincter function. Part 4: Effectiveness of the motor reinnervation

description: The original design and necessary modifications of the project plan are as described in part 1 of this series (26). The current study is part 4 of a series reports and results from 30 animals with three main groups (Fig. 1A). The ObNT-ScNT Reinn group consisted of 8 dogs that were in the study a total of 22 months (22 ± 0.4 mo, mean ± SEM, Fig. 1B). At study onset, these ObNT-ScNT Reinn animals functionally decentralized by bilaterally transecting the dorsal roots of L7, all spinal roots caudal to L7, and the hypogastric nerves, followed by a 9-13 mo recovery period (10.4 ± 0.7 mo, Fig. 1C), then reinnervation by transfer of the obturator nerve to the vesical branch of the pelvic nerve, as well as a branch of the sciatic nerve to the pudendal nerve, that was then followed by an additional 8-12 mo recovery (11.9 ± 0.4 mo, Fig. 1C). The Decentralized group consisted of 4 animals that underwent similar decentralization followed by an 11-21 mo recovery (18 ± 2.5 mo, Fig. 1B), but no reinnervation surgeries. Controls consists of 7 sham-operated and 11 unoperated animals (18 total; Fig. 1A). There is some overlap with the pilot study (22) and part 2 (25) of this series. Specifically, we included squat-and-void posture data from 3 ObNT-ScNT Reinn animals, 1 Decentralized animal, and 8 Control animals (5 sham-operated and 3 sham-unoperated) from the small pilot study, and in vivo electrophysiology data for peripheral nerve-evoked bladder, urethra and anal sphincter contractility from 3 ObNT-ScNT Reinn animals from the pilot study (22). We also included the in vivo peripheral nerve-evoked bladder contractility graph from Part 2 of this series (25) for comparison purposes to new additional data. Unique to this manuscript are: 1) data from 18 additional animals, 2) report of defecation postures; 3) segmental spinal root/cord-evoked bladder, urethra and anal sphincter contractility data from all animals from L2-S3 to more closely match reports that spinal cord input to the obturator nerve is nearer to L3-L6 (20, 27-29); 4) peripheral nerve-evoked urethra and anal sphincter contractility data from the Decentralized and Control animals, and 5 additional ObNT-ScNT Reinn animals; 5) retrograde dye labeling data in the spinal cord ventral horn segments from L2-S3 after dye injections into the bladder and urethra sphincter; 6) Rexed laminar location of these labeled neurons in the spinal cord; and 7) correlations between these various outcomes. Because of the inclusion of the urethral and anal sphincter data, we renamed the reinnervated group to ObNT-ScNT Reinn (different from prior studies in which we focused on the obturator nerve transfer to the pelvic nerve results, and thus named the reinnervated group as “ObNT-Reinn”).
description: The original design and necessary modifications of the project plan are as described in part 1 of this series (26). The current study is part 4 of a series reports and results from 30 animals with three main groups (Fig. 1A). The ObNT-ScNT Reinn group consisted of 8 dogs that were in the study a total of 22 months (22 ± 0.4 mo, mean ± SEM, Fig. 1B). At study onset, these ObNT-ScNT Reinn animals functionally decentralized by bilaterally transecting the dorsal roots of L7, all spinal roots caudal to L7, and the hypogastric nerves, followed by a 9-13 mo recovery period (10.4 ± 0.7 mo, Fig. 1C), then reinnervation by transfer of the obturator nerve to the vesical branch of the pelvic nerve, as well as a branch of the sciatic nerve to the pudendal nerve, that was then followed by an additional 8-12 mo recovery (11.9 ± 0.4 mo, Fig. 1C). The Decentralized group consisted of 4 animals that underwent similar decentralization followed by an 11-21 mo recovery (18 ± 2.5 mo, Fig. 1B), but no reinnervation surgeries. Controls consists of 7 sham-operated and 11 unoperated animals (18 total; Fig. 1A).