Skip to main content
SpringerLink
Log in

Anorectal Anatomy and Physiology

  • Chapter
  • First Online:
Fundamentals of Anorectal Surgery

Abstract

In this chapter, the anatomy of the anal canal, rectum and pelvic floor will be reviewed in detail with clinical correlations to the relevant surgical anatomy whenever possible. After a complete discussion of the anatomy, the physiology of anorectum and pelvic floor will be addressed with special attention regarding the physiology of defecation and fecal continence. Colonic motility plays a direct role in the physiology of defecation and will also be covered in this chapter.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Log in via an institution
Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 149.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Hardcover Book
USD 199.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

References

  1. Milligan ETC, Morgan CN. Surgical anatomy of the anal canal: with special reference to anorectal fistulae. Lancet. 1934;2(5804):1150–6.

    Article  Google Scholar 

  2. Milligan ETC, Morgan CN, Jones LE, Officer R. Surgical anatomy of the anal canal, and the operative treatment of haemorrhoids. Lancet. 1937;2:1119–24.

    Article  Google Scholar 

  3. Carmichael JC, Mills S. Anatomy and embryology of the colon, rectum, and anus. In: Steele SR, Hull TL, Saclarides TJ, Senagore AJ, Whitlow CB, editors. The ASCRS textbook of colon and rectal surgery. 3rd ed. New York: Springer; 2016. p. 3–26.

    Chapter  Google Scholar 

  4. Nivatvongs S, Stern HS, Fryd DS. The length of the anal canal. Dis Colon Rectum. 1981;24(8):600–1.

    Article  CAS  PubMed  Google Scholar 

  5. Morren GL, Beets-Tan RG, van Engelshoven JM. Anatomy of the anal canal and perianal structures as defined by phased-array magnetic resonance imaging. Br J Surg. 2001;88(11):1506–12.

    Article  CAS  PubMed  Google Scholar 

  6. Parks AG. Pathogenesis and treatment of fistuila-in-ano. Br Med J. 1961;1(5224):463–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Hiller RI. Anal anatomy with reference to the white line of Hilton and the pecten of Stroud. Ann Surg. 1935;102(1):81–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Lilius HG. Fistula-in-ano, an investigation of human foetal anal ducts and intramuscular glands and a clinical study of 150 patients. Acta Chir Scand Suppl. 1968;383:7–88.

    CAS  PubMed  Google Scholar 

  9. Barleben A, Mills S. Anorectal anatomy and physiology. Surg Clin N Am. 2010;90(1):1–15.

    Article  PubMed  Google Scholar 

  10. Sboarina A, Minicozzi A, Segattini C, Leopardi F, Lombardo F, Passeri V, et al. Shape and volume of internal anal sphincter showed by three-dimensional anorectal ultrasonography. Eur J Radiol. 2012;81(7):1479–82.

    Article  CAS  PubMed  Google Scholar 

  11. Haas PA, Fox TA Jr. The importance of the perianal connective tissue in the surgical anatomy and function of the anus. Dis Colon Rectum. 1977;20(4):303–13.

    Article  CAS  PubMed  Google Scholar 

  12. Tsukada Y, Ito M, Watanabe K, Yamaguchi K, Kojima M, Hayashi R, et al. Topographic anatomy of the anal sphincter complex and levator ani muscle as it relates to intersphincteric resection for very low rectal disease. Dis Colon Rectum. 2016;59(5):426–33.

    Article  PubMed  Google Scholar 

  13. Treitz W. Ueber einen neuen Muskel am Duodenum des Menschen, uber elsatische Sehnen, und einige andere anatomische Verhaltnisse. Vierteljahrschrift Praktische Heilkunde (Prager). 1853;37:133–44.

    Google Scholar 

  14. Chang SC, JJM S, Shih JYM, Lee HHC. Review of Treitz’s muscles and their implications in a hemorrhoidectomy and hemorrhoidopexy. Fu-Jen J Med. 2006;4(1):1–6.

    Google Scholar 

  15. Thomson WH. The nature of haemorrhoids. Br J Surg. 1975;62(7):542–52.

    Article  CAS  PubMed  Google Scholar 

  16. Goligher JC, Leacock AG, Brossy JJ. The surgical anatomy of the anal canal. Br J Surg. 1955;43(177):51–61.

    Article  CAS  PubMed  Google Scholar 

  17. Bollard RC, Gardiner A, Lindow S, Phillips K, Duthie GS. Normal female anal sphincter: difficulties in interpretation explained. Dis Colon Rectum. 2002;45(2):171–5.

    Article  CAS  PubMed  Google Scholar 

  18. Hussain SM, Stoker J, Lameris JS. Anal sphincter complex: endoanal MR imaging of normal anatomy. Radiology. 1995;197(3):671–7.

    Article  CAS  PubMed  Google Scholar 

  19. Wunderlich M, Swash M. The overlapping innervation of the two sides of the external anal sphincter by the pudendal nerves. J Neurol Sci. 1983;59(1):97–109.

    Article  CAS  PubMed  Google Scholar 

  20. Mittal RK, Bhargava V, Sheean G, Ledgerwood M, Sinha S. Purse-string morphology of external anal sphincter revealed by novel imaging techniques. Am J Physiol Gastrointest Liver Physiol. 2014;306(6):G505–14.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Kinugasa Y, Arakawa T, Abe S, Ohtsuka A, Suzuki D, Murakami G, et al. Anatomical reevaluation of the anococcygeal ligament and its surgical relevance. Dis Colon Rectum. 2011;54(2):232–7.

    Article  PubMed  Google Scholar 

  22. Jin ZW, Hata F, Jin Y, Murakami G, Kinugasa Y, Abe S. The anococcygeal ligaments: cadaveric study with application to our understanding of incontinence in the elderly. Clin Anat. 2015;28(8):1039–47.

    Article  PubMed  Google Scholar 

  23. DeLancey JO, Morgan DM, Fenner DE, Kearney R, Guire K, Miller JM, et al. Comparison of levator ani muscle defects and function in women with and without pelvic organ prolapse. Obstet Gynecol. 2007;109(2 Pt 1):295–302.

    Article  PubMed  Google Scholar 

  24. Shafik A. New concept of the anatomy of the anal sphincter mechanism and the physiology of defecation. II. Anatomy of the levator ani muscle with special reference to puborectalis. Investig Urol. 1975;13(3):175–82.

    CAS  Google Scholar 

  25. Betschart C, Kim J, Miller JM, Ashton-Miller JA, DeLancey JO. Comparison of muscle fiber directions between different levator ani muscle subdivisions: in vivo MRI measurements in women. Int Urogynecol J. 2014;25(9):1263–8.

    Article  PubMed  PubMed Central  Google Scholar 

  26. Levi AC, Borghi F, Garavoglia M. Development of the anal canal muscles. Dis Colon Rectum. 1991;34(3):262–6.

    Article  CAS  PubMed  Google Scholar 

  27. Grigorescu BA, Lazarou G, Olson TR, Downie SA, Powers K, Greston WM, et al. Innervation of the levator ani muscles: description of the nerve branches to the pubococcygeus, iliococcygeus, and puborectalis muscles. Int Urogynecol J. 2008;19(1):107–16.

    Article  Google Scholar 

  28. Wallner C, Maas CP, Dabhoiwala NF, Lamers WH, DeRuiter MC. Evidence for the innervation of the puborectalis muscle by the levator ani nerve. Neurogastroenterol Motil. 2006;18(12):1121–2.

    Article  CAS  PubMed  Google Scholar 

  29. Shafik A. A new concept of the anatomy of the anal sphincter mechanism and the physiology of defecation. VIII. Levator hiatus and tunnel: anatomy and function. Dis Colon Rectum. 1979;22(8):539–49.

    Article  CAS  PubMed  Google Scholar 

  30. Andrew BP, Shek KL, Chantarasorn V, Dietz HP. Enlargement of the levator hiatus in female pelvic organ prolapse: cause or effect? Aust N Z J Obstet Gynaecol. 2013;53(1):74–8.

    Article  PubMed  Google Scholar 

  31. DeLancey JO, Sorensen HC, Lewicky-Gaupp C, Smith TM. Comparison of the puborectal muscle on MRI in women with POP and levator ani defects with those with normal support and no defect. Int Urogynecol J. 2012;23(1):73–7.

    Article  PubMed  Google Scholar 

  32. Heald RJ, Moran BJ. Embryology and anatomy of the rectum. Semin Surg Oncol. 1998;15(2):66–71.

    Article  CAS  PubMed  Google Scholar 

  33. Najarian MM, Belzer GE, Cogbill TH, Mathiason MA. Determination of the peritoneal reflection using intraoperative proctoscopy. Dis Colon Rectum. 2004;47(12):2080–5.

    Article  PubMed  Google Scholar 

  34. Abramson DJ. The valves of Houston in adults. Am J Surg. 1978;136(3):334–6.

    Article  CAS  PubMed  Google Scholar 

  35. Chapuis P, Bokey L, Fahrer M, Sinclair G, Bogduk N. Mobilization of the rectum: anatomic concepts and the bookshelf revisited. Dis Colon Rectum. 2002;45(1):1–8. discussion -9.

    Article  PubMed  Google Scholar 

  36. Heald RJ, Husband EM, Ryall RD. The mesorectum in rectal cancer surgery—the clue to pelvic recurrence? Br J Surg. 1982;69(10):613–6.

    Article  CAS  PubMed  Google Scholar 

  37. Nomina anatomica, 6th ed. Singapore: Churchill Livingstone; 1989.

    Google Scholar 

  38. Quirke P, Steele R, Monson J, Grieve R, Khanna S, Couture J, et al. Effect of the plane of surgery achieved on local recurrence in patients with operable rectal cancer: a prospective study using data from the MRC CR07 and NCIC-CTG CO16 randomised clinical trial. Lancet. 2009;373(9666):821–8.

    Article  PubMed  PubMed Central  Google Scholar 

  39. Church JM, Raudkivi PJ, Hill GL. The surgical anatomy of the rectum—a review with particular relevance to the hazards of rectal mobilisation. Int J Color Dis. 1987;2(3):158–66.

    Article  CAS  Google Scholar 

  40. Sato K, Sato T. The vascular and neuronal composition of the lateral ligament of the rectum and the rectosacral fascia. Surg Radiol Anat. 1991;13(1):17–22.

    Article  CAS  PubMed  Google Scholar 

  41. Crapp AR, Cuthbertson AM. William Waldeyer and the rectosacral fascia. Surg Gynecol Obstet. 1974;138(2):252–6.

    CAS  PubMed  Google Scholar 

  42. Gordon PH, Nivatvongs S. Principles and practice of surgery for the colon, rectum, and anus. 3rd ed. New York: Informa Healthcare; 2007.

    Google Scholar 

  43. Lindsey I, Guy RJ, Warren BF, Mortensen NJ. Anatomy of Denonvilliers’ fascia and pelvic nerves, impotence, and implications for the colorectal surgeon. Br J Surg. 2000;87(10):1288–99.

    Article  CAS  PubMed  Google Scholar 

  44. Richardson AC. The rectovaginal septum revisited: its relationship to rectocele and its importance in rectocele repair. Clin Obstet Gynecol. 1993;36(4):976–83.

    Article  CAS  PubMed  Google Scholar 

  45. Llauger J, Palmer J, Perez C, Monill J, Ribe J, Moreno A. The normal and pathologic ischiorectal fossa at CT and MR imaging. Radiographics. 1998;18(1):61–82. quiz 146.

    Article  CAS  PubMed  Google Scholar 

  46. Courtney H. The posterior subsphincteric space; its relation to posterior horseshoe fistula. Surg Gynecol Obstet. 1949;89(2):222–6.

    CAS  PubMed  Google Scholar 

  47. Wang G-J. Anatomy of the lateral ligaments of the rectum: a controversial point of view. World J Gastroenterol. 2010;16(43):5411.

    Article  PubMed  PubMed Central  Google Scholar 

  48. Corman ML. Classic articles in colonic and rectal surgery. A method of performing abdominoperineal excision for carcinoma of the rectum and of the terminal portion of the pelvic colon: by W. Ernest Miles, 1869-1947. Dis Colon Rectum. 1980;23(3):202–5.

    Article  CAS  PubMed  Google Scholar 

  49. Heald RJ, Ryall RD. Recurrence and survival after total mesorectal excision for rectal cancer. Lancet. 1986;1(8496):1479–82.

    Article  CAS  PubMed  Google Scholar 

  50. Nano M, Dal Corso HM, Lanfranco G, Ferronato M, Hornung JP. Contribution to the surgical anatomy of the ligaments of the rectum. Dis Colon Rectum. 2000;43(11):1592–7. discussion 7–8.

    Article  CAS  PubMed  Google Scholar 

  51. Lin M, Chen W, Huang L, Ni J, Yin L. The anatomy of lateral ligament of the rectum and its role in total mesorectal excision. World J Surg. 2010;34(3):594–8.

    Article  PubMed  Google Scholar 

  52. Michaels NA, Siddharth P, Kornblith PL, Park WW. The variant blood supply to the small and large intestines: its importance in regional resections. A new anatomic study based on four hundred dissections with a complete review of the literature. J Int Coll Surg. 1963;39:127–70.

    Google Scholar 

  53. Schuurman JP, Go PM, Bleys RL. Anatomical branches of the superior rectal artery in the distal rectum. Color Dis. 2009;11(9):967–71.

    Article  CAS  Google Scholar 

  54. Ayoub SF. Arterial supply to the human rectum. Acta Anat (Basel). 1978;100(3):317–27.

    Article  CAS  Google Scholar 

  55. van Meegdenburg MM, Heineman E, Broens PM. Pudendal neuropathy alone results in urge incontinence rather than in complete fecal incontinence. Dis Colon Rectum. 2015;58(12):1186–93.

    Article  PubMed  Google Scholar 

  56. Gooneratne ML, Scott SM, Lunniss PJ. Unilateral pudendal neuropathy is common in patients with fecal incontinence. Dis Colon Rectum. 2007;50(4):449–58.

    Article  PubMed  Google Scholar 

  57. Connell AM, Hilton C, Irvine G, Lennard-Jones JE, Misiewicz JJ. Variation of bowel habit in two population samples. Br Med J. 1965;2(5470):1095–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  58. Phillips SF, Giller J. The contribution of the colon to electrolyte and water conservation in man. J Lab Clin Med. 1973;81(5):733–46.

    CAS  PubMed  Google Scholar 

  59. Luboshits J, Goldberg G, Chubadi R, Achiron A, Atsmon J, Hayslett JP, et al. Functional adaptation of rat remnant colon after proximal hemicolectomy. Dig Dis Sci. 1992;37(2):175–8.

    Article  CAS  PubMed  Google Scholar 

  60. Jorge JM, Habr-Gama A, Wexner SD, Pinotti HW. Practical physiologic evaluation of the colon, rectum and anus. Rev Hosp Clin. 1994;49(5):196–8.

    CAS  Google Scholar 

  61. Cook IJ, Furukawa Y, Panagopoulos V, Collins PJ, Dent J. Relationships between spatial patterns of colonic pressure and individual movements of content. Am J Physiol Gastrointest Liver Physiol. 2000;278(2):G329–41.

    Article  CAS  PubMed  Google Scholar 

  62. Scott SM. Manometric techniques for the evaluation of colonic motor activity: current status. Neurogastroenterol Motil. 2003;15(5):483–513.

    Article  CAS  PubMed  Google Scholar 

  63. Torsoli A, Ramorino ML, Ammaturo MV, Capurso L, Paoluzi P, Anzini F. Mass movements and intracolonic pressures. Am J Dig Dis. 1971;16(8):693–6.

    Article  CAS  PubMed  Google Scholar 

  64. Hagger R, Kumar D, Benson M, Grundy A. Colonic motor activity in slow-transit idiopathic constipation as identified by 24-h pancolonic ambulatory manometry. Neurogastroenterol Motil. 2003;15(5):515–22.

    Article  CAS  PubMed  Google Scholar 

  65. Dinning PG, Zarate N, Hunt LM, Fuentealba SE, Mohammed SD, Szczesniak MM, et al. Pancolonic spatiotemporal mapping reveals regional deficiencies in, and disorganization of colonic propagating pressure waves in severe constipation. Neurogastroenterol Motil. 2010;22(12):e340–9.

    Article  CAS  PubMed  Google Scholar 

  66. Chowdhury AR, Dinoso VP, Lorber SH. Characterization of a hyperactive segment at the rectosigmoid junction. Gastroenterology. 1976;71(4):584–8.

    CAS  PubMed  Google Scholar 

  67. Goligher JC, Hughes ES. Sensibility of the rectum and colon. Its role in the mechanism of anal continence. Lancet. 1951;1(6654):543–7.

    Article  CAS  PubMed  Google Scholar 

  68. Denis P, Colin R, Galmiche JP, Geffroy Y, Hecketsweiler P, Lefrancois R, et al. Elastic properties of the rectal wall in normal adults and in the patients with ulcerative colitis. Gastroenterology. 1979;77(1):45–8.

    CAS  PubMed  Google Scholar 

  69. Varma JS, Smith AN, Busuttil A. Correlation of clinical and manometric abnormalities of rectal function following chronic radiation injury. Br J Surg. 1985;72(11):875–8.

    Article  CAS  PubMed  Google Scholar 

  70. Wexner SD, James K, Jagelman DG. The double-stapled ileal reservoir and ileoanal anastomosis. A prospective review of sphincter function and clinical outcome. Dis Colon Rectum. 1991;34(6):487–94.

    Article  CAS  PubMed  Google Scholar 

  71. Parks AG. Royal Society of Medicine, Section of Proctology; Meeting 27 November 1974. President’s address. Anorectal incontinence. Proc R Soc Med. 1975;68(11):681–90.

    CAS  PubMed  PubMed Central  Google Scholar 

  72. Scharli AF, Kiesewetter WB. Defecation and continence: some new concepts. Dis Colon Rectum. 1970;13(2):81–107.

    Article  CAS  PubMed  Google Scholar 

  73. Buser WD, Miner PB Jr. Delayed rectal sensation with fecal incontinence. Successful treatment using anorectal manometry. Gastroenterology. 1986;91(5):1186–91.

    Article  CAS  PubMed  Google Scholar 

  74. Swash M. Histopathology of pelvic floor muscles in pelvic floor disorders. In: Henry MM, Swash M, editors. Coloproctology and the pelvic floor. London: Butterworth-Heinemann; 1992. p. 173–83.

    Google Scholar 

  75. Snooks SJ, Swash M. The innervation of the muscles of continence. Ann R Coll Surg Engl. 1986;68(1):45–9.

    CAS  PubMed  PubMed Central  Google Scholar 

  76. Bartolo DC, Roe AM, Virjee J, Mortensen NJ. Evacuation proctography in obstructed defaecation and rectal intussusception. Br J Surg. 1985;72(Suppl):S111–6.

    Article  PubMed  Google Scholar 

  77. Palit S, Lunniss PJ, Scott SM. The physiology of human defecation. Dig Dis Sci. 2012;57(6):1445–64.

    Article  PubMed  Google Scholar 

  78. Jorge JM, Wexner SD. Anorectal manometry: techniques and clinical applications. South Med J. 1993;86(8):924–31.

    Article  CAS  PubMed  Google Scholar 

  79. Gibbons CP, Trowbridge EA, Bannister JJ, Read NW. Role of anal cushions in maintaining continence. Lancet. 1986;1(8486):886–8.

    Article  CAS  PubMed  Google Scholar 

  80. Jorge JM, Habr-Gama A. The value of sphincteric asymmetry index analysis in anal incontinence (abstract). Dis Colon Rectum. 1997;40:A14–5.

    Google Scholar 

  81. Sun WM, Read NW, Donnelly TC. Impaired internal anal sphincter in a subgroup of patients with idiopathic fecal incontinence. Gastroenterology. 1989;97(1):130–5.

    Article  CAS  PubMed  Google Scholar 

  82. Courtney H. Anatomy of the pelvic diaphragm and anorectal musculature as related to sphincter preservation in anorectal surgery. Am J Surg. 1950;79(1):155–73.

    Article  CAS  PubMed  Google Scholar 

  83. Shafik A. A new concept of the anatomy of the anal sphincter mechanism and the physiology of defecation. III. The longitudinal anal muscle: anatomy and role in anal sphincter mechanism. Investig Urol. 1976;13(4):271–7.

    CAS  Google Scholar 

  84. Lunniss PJ, Phillips RK. Anatomy and function of the anal longitudinal muscle. Br J Surg. 1992;79(9):882–4.

    Article  CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Surgery, Virginia Mason Medical Center, Seattle, WA, USA

    Ravi Moonka & Joseph C. Carmichael

Authors
  1. Ravi Moonka
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Joseph C. Carmichael
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Joseph C. Carmichael .

Editor information

Editors and Affiliations

  1. Department of Colon and Rectal Surgery, Ochsner Clinic Foundation, New Orleans, LA, USA

    David E. Beck

  2. Department of Colon and Rectal Surgery, Cleveland Clinic, Cleveland, OH, USA

    Scott R. Steele

  3. Department of Colon and Rectal Surgery, Cleveland Clinic Florida, Weston, FL, USA

    Steven D. Wexner

Rights and permissions

Reprints and permissions

Copyright information

© 2019 Springer International Publishing AG, part of Springer Nature

About this chapter

Check for updates. Verify currency and authenticity via CrossMark

Cite this chapter

Moonka, R., Carmichael, J.C. (2019). Anorectal Anatomy and Physiology. In: Beck, D., Steele, S., Wexner, S. (eds) Fundamentals of Anorectal Surgery. Springer, Cham. https://doi.org/10.1007/978-3-319-65966-4_1

Download citation

  • DOI: https://doi.org/10.1007/978-3-319-65966-4_1

  • Published:

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-319-65965-7

  • Online ISBN: 978-3-319-65966-4

  • eBook Packages: MedicineMedicine (R0)

Publish with us

Policies and ethics

Search

Navigation