Functional perineal colostomy with pudendal nerve anastomosis following anorectal resection: a cadaver operation study on a new procedure.
BACKGROUND
We have previously studied functional perineal colostomy that used skeletal muscle with pudendal nerve anastomosis (PNA) following anorectal resection in an animal model. In that study the neosphincter reconstructed with PNA achieved the proper functions of the external anal sphincter resulting in a satisfactory defecatory condition. This study was a preliminary step before applying this procedure to human beings.


METHODS
We reconstructed a new anal sphincter by using the lower part of the gluteus maximus muscle (lower GMM) with PNA in a total of six sides of four human cadavers and investigated the anatomic problems associated with this procedure.


RESULTS
We classified the branching patterns of the inferior gluteal nerve into three types. The length of the branches of the inferior gluteal nerve to the lower GMM varied from 32 to 76 mm (median, 57 mm). The length of the pudendal nerve (PN) passing out below the sacrotuberous ligament varied from 21 to 44 mm (median, 29.5 mm). The PN was anastomosed to the nerve innervating the lower GMM with the redundancy of 17 to 36 mm (median, 24.5 mm). In all cases the anal sphincter reconstruction with a PNA maneuver was anatomically feasible by using the lower GMM. The length of the new anal canal was 65 to 80 mm (median, 67.5 mm).


CONCLUSIONS
The PNA maneuver was an anatomically applicable method to make a neoanus in human beings. Preparation for the application of this method to human beings was accomplished.
Sato
T
T
Department of Surgery, Jichi Medical School, Tochigi-ken, Japan.
Konishi
F
F
Kanazawa
K
K
D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal / Q000294:innervation* / Q000601:surgery*; D000714:Anastomosis, Surgical; D002102:Cadaver; D003125:Colostomy / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000601:surgery*; D010502:Perineum / Q000294:innervation* / Q000601:surgery*