Pudendal nerve terminal motor latency in patients with or without soiling 5 years or more after low anterior resection for lower rectal cancer.
BACKGROUND
To clarify the neurological function with respect to external anal sphincter (EAS) muscles in patients with or without soiling after low anterior resection (LAR) for lower rectal cancer, we examined the terminal motor latency in the pudendal motor nerves (PNTML).


METHODS
Thirty-eight patients after LAR for lower rectal cancer were studied electrophysiologically and compared with 30 healthy volunteers as controls (19 men and 11 women, aged 44 to 76 years of age, with a mean age of 65.5 years). Patients after LAR were divided into two groups [18 patients with soiling (12 men and 6 women, aged 51 to 77 years with a mean age of 64.8 years), 20 patients without soiling (13 men and 7 women, aged 47 to 75 years with a mean age of 62.1 years)]. The mean follow-up time from LAR was 67.2 months (range 60-84 months). Bilateral (left-sided and right-sided) PNTML tests were performed on all patients in order to measure the latency of the response in the bilateral EAS muscle following digitally directed transrectal pudendal nerve stimulation.


RESULTS
The distance from the anal verge to the level of anastomosis in patients with soiling (mean, 2.2 cm) was significantly shorter than that in patients without soiling (mean, 4.1 cm) (P < 0.05). Conduction delay of the bilateral PNTML in patients with soiling was longer than that in patients without soiling and normal subjects, significantly (P < 0.01, respectively). There was no significant difference between the right-sided and left-sided PNTML.


CONCLUSIONS
These findings support the hypothesis that soiling after LAR may be partially caused by damage to the bilateral pudendal motor nerves.
Tomita
Ryouichi
R
Department of Surgery, Nippon Dental University School of Dentistry at Tokyo, 2-3-16 Fujimi Chiyoda-ku, Tokyo, 102-8158, Japan. rtomita-ndus@mvg.biglobe.ne.jp
Igarashi
Seigo
S
Ikeda
Taro
T
Koshinaga
Tsugumichi
T
Fujisaki
Shigeru
S
Tanjoh
Katsuhisa
K
D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000294:innervation* / Q000503:physiopathology; D000714:Anastomosis, Surgical; D016022:Case-Control Studies; D005242:Fecal Incontinence / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology*; D011183:Postoperative Complications; D011930:Reaction Time / Q000502:physiology*; D012004:Rectal Neoplasms / Q000601:surgery*