Diseases of the anus, rectum, and sigmoid, for the use of students and general practitioners

Front matter

Class - Book.

COPYRIGHT DEPOSIT

DISEASES OF

Preface

It is now many months since I set out upon the task of gathering into one volume all the information concerning diseases of the rectum and anus, derived from my own experience and that of others, which would be helpful to both students and the general practitioner. The latter, owing to the nature of the symptoms and the inaccessibility of a specialist, has often the entire treatment in his hands and has to face a situation in which a complete pathological knowledge of the conditions is absolutely essential.

The maladies discussed are very common but very stubborn and particularly annoying and painful. My chief care has been to include the most recent and effective methods of cure and to give these comprehensively and succinctly, knowing a busy doctor will not search for therapeutic or operative technic hidden in verbose phrasing. Nor do I quote many cases only slightly dissimilar, but rather those of rare finding or needed for the elucidation of methods advised.

The pictures, numbering one hundred and fifty-two, most of them specially drawn, are fitly wedded to the text when such union engenders a fuller appreciation of facts stated. The labor of my artist, Walter R. Gale, and the promptness and intelligence with which he has availed himself of every proffered opportunity to witness operations and dissections deserves as much attention from my readers as praise from myself.

In the chapter on Constipation I have striven to write in a form most convenient for reference, and to cover the whole etiological field. In another part of the book are descriptions of certain forms of ulceration not found in any text-book that I know of, such as Infection by Bilharzia Haematobia, Actinomycosis, and Spontaneous Gangrene of the Rectum. Con-

PREFACE

genital Idiopathic Dilatation of the Colon (Hirschsprung's Disease) is also described at length.

Great assistance has been given by my colleague, Dr. Arthur Hebb, who made all the dissections necessary for the original anatomical plates and some of the outline drawings, looked up references, and helped me in so many ways that my most appreciative thanks are due to him. To the members of the Proctologic Society and to my confreres, who have all so courteously and promptly responded to every request, I tender my very cordial thanks.

My thanks are due to Miss Davina Waterson not only for her corrections of the manuscript but also for her kind criticism of the contents, and they are also due to the J. B. Lippincott Company, who have done all in their power to procure the best possible results.

S. T. E.

CHAPTER I. Anatomy, and Physiology

Anatomy — Development — Pelvic Triangles — Ischiorectal Fossae — Muscles of the Perinseal — Muscles of the Anorectal Region — Nerve Supply — Lymphatics — The Rectum — Mucous Membrane — Submucous Layer — Muscular Wall — Columns of Morgagni — Houston's Valves — Arteries — Relation of Rectum — Sigmoid Flexure — Elood Supply — Nerve Supply — Physiology — Defecation 1-26

Chapter V

Simple Perineal Ulcerations — Ulceration of the Anal Canal — Ulceration of the Rectum and Sigmoid — Follicular Ulceration — Specific Ulceration — Tubercular Ulceration — -Acute Tubercular Proctitis — Dysenteric Ulceration — Valvular Caecostomy — Appendicostomy — Ulceration due to Mixed Infection — Venereal Ulceration — Diphtheritic Ulceration — Ulceration due to Bilharzia Hae-

matobia — Actinomycosis — Gangrene of the Rectum 1 13-150

vii viii CONTENTS

CHAPTER IX. Anorectal Fistula

Complete Fistula — Incomplete Fistula — -Constitutional Causes and Complications — Tuberculosis — Syphilis — Blind External Fistula — Blind Internal Fistula — Complete Fistula — Pathology — Prognosis — Treatment — Non-operative Treatment — Operative — Excision of Fistula — Excision with Immediate Suture — Complex Fistula — Complications Attending and Following Operation for Fistula — Treatment for Incontinence — Protracted Suppuration Following Operation for Fistula — Complicated Fistula — Fistulae that Originate in Diseased Bone — Fistula Originating in Other Organs — Operation — Complete Excision of the Fistulous Tract Combined with Perineorrhaphy 192-239

CHAPTER X. Hemorrhoids

Pathology — Etiology — Complications — Predisposing Causes — Exciting Causes — External Hemorrhoids — Internal Hemorrhoids — Mixed Hemorrhoids — Thrombotic — Connective-Tissue — Treatment of Internal Hemorrhoids — Injection Method — Electrolysis — Angiotribe — Operative Treatment — Ligature — Clamp and Cautery — Complications Following Operation 240-278

CONTENTS ix

CHAPTER XI. Prolapse of the Rectum

Incomplete — Etiology — Symptoms — Treatment — Complete — First Degree — Second Degree — -Third Degree — Symptoms — Etiology — Pathology — Treatment — Reduction — Operative Treatment — Rectopexy — Sigmoidopexy — Excision — Complications of Prolapse — Rupture of the Hernial Sac 279-307

CHAPTER XII. Stricture of the Rectum

Classification — Annular — Tubular — Linear — Congenital Stricture — Intramural Stricture— Neoplastic Stricture— Spasmodic Stricture — Inflammatory Stricture — Location — Simple Inflammatory Stricture — Traumatic Stricture — Tubercular Stricture — Syphilitic Stricture — Pathology — Symptoms — Dilatation — Diagnosis — Treatment — Preventive Treatment — Palliative Treatment — Electrolysis — Gradual Dilatation — Operative Treatment — Colostomy — Excision — Proctoplasty 308-327

CHAPTER XIII. Pruritus Ani

Reflex Causes — Direct Causes — Symptoms — Treatment — Local —

Operative 328-337

CHAPTER XIV. Colostomy

Left Inguinal — Permanent Left Inguinal — Technic — Temporary Colostomy — Closure of Artificial Anus 338-349

Chapter XV

Pathological Growths, or Tumors of the Anus, Rectum, and Sigmoid.

Malignant Tumors — Innocent Tumors— Classification of Tumors — Benign Tumors of the Rectum — Polypus — Fibroma — Myxoma — Lipoma — Enchrondroma — Lymphoma — Angioma — Papilloma — Hard Papilloma — Condyloma Acuminatum — Soft Papilloma — Adenoma — Adenoma Proper — Adenomatosis — Adenoma with Bilharzia Haematobia — Symptoms — Diagnosis — Malignant Transformation — Treatment — Colostomy and Caecostomy— Teratoma — Dermoids of the Rectum — Postrectal Dermoids — Rectal Dermoids — Postanal Dimples — Hypertrophied Anal Papilla — Malignant Tumors of the Rectum — Carcinoma and Sarcoma — x CONTENTS

Types — Seat of Disease — Epithelioma — Adenocarcinoma — Medullary Carcinoma — Scirrhous Cancer — Colloid Degeneration — Symptoms — Manner of Extension — Diagnosis — Treatment — Inoperable Cases — Palliative Treatment — Colostomy as a Palliative Measure — Operable Cases — Sarcoma — Types of Sarcoma — Symptoms — Diagnosis — Treatment — Prognosis 350-400

CHAPTER XX. Pathological Lesions of the Coccyx

Malformations — Treatment — Fractures and Dislocations of the Coccyx—Treatment — Sacrococcygeal Tumors and Cysts — Treatment — Tapping — Partial Resection — Complete Extirpation — Coccygodynia — Etiology — Pathology — Symptoms — Diagnosis — Palliative Treatment— Surgical Method — Tenotomy — Total Excision 442—449

CHAPTER XXI. Congenital Idiopathic Dilatation of the Colon: Hirschsprung's Disease

History — Terms and Synonyms — Classification — Etiology — Cardinal Symptoms — Prognosis — Treatment — Pathology — Lateral Anastomosis 450-462

ILLUSTRATIONS

FIG. PAGE

i. Divisions of the pelvic outlet 2

2. Male perineum. (Plate.) 4

3. Levator ani muscle • • 6

4. Sympathetic nerve supply to rectum 7

5. Sacral plexus. (Plate.) 8

6. Sagittal section of the pelvis 9

7. Sagittal section of the rectum. 11

8. Blood supply to rectum, etc. (Plate.) 16

9. Knee-chest position 28

10. Mathews and Hanes examining table 31

11. Lithotomy position 32

12. W. D. Allison's examining table 34

13. W. D. Allison's cabinet 34

14. Earle's single-blade speculuni 35

15. Murray's speculum 36

16. Tuttle's pneumatic proctoscope 37

17. Pennington's bivalve speculum 39

18. Kelly's graduated conical dilator 39

19. Dudley Roberts's rubber bag dilators 40

20. Rectal curette , 42

21. Alligator forceps • • 43

22. Silver probe 43

23. Grooved directors 43

24. Murray's scrotal holder and shield 44

25. Murray's holder and shield in position 45

26. Showing perineal nerve supply 48

27. Testing resistance of rectal valve 78

28. Martin's over and under valvotomy scalpels 79

29. Pennington's clip for cutting rectal valves 79

30. Pennington's clip applied 80

31. Lynch's electric angiotribe 81

2,2. J. G. Clark's lateral anastomosis 83

22>. Wolbarst's rectal irrigating tube 94

34. Wolbarst's rectal irrigating tube 95

35. Tumor of the sigmoid flexure 103

36. Tubercular ulceration encircling the sigmoid 121

37. Gibson's method showing catheter in caecum 130

38. Catheter in caecum, wound closed 131

39. Gant's caecostomy. (Plate.) 132

40. Different steps in Gant's caecostomy 133 xii ILLUSTRATIONS

FIG. PAGE

41. Turtle's modification of Weir's appendicostomy 135

42. Catheter in position, and ligature 136

43. Gant's appendicostomy. {Plate.) 136

44. Spirochete pallida from anal condyloma ■ 141

45. Abscesses around anus and rectum 154

46. Fissure in ano 164

47. Entire absence of anus 173

48. Anal opening at an abnormal point 174

49. Rectum ending in cul-de-sac; anus opening into vagina 175

50. Rectum entirely absent 176

51. Rectum arrested above anus 177

52. Rectum opening into some other viscus 178

53. Rectum opens at the glans penis 179

54. Rectum opens into the vagina 180

55. Rectum opens into the bladder 181

56. Rectum descends posteriorly to anal canal 182

57. Peritoneal cul-de-sac between rectum and anus 183

58. Cord between blind ends of anus and rectum 184

59. Rectum opens into vagina ; anus into blind pouch 189

60. Showing Fig. 59 after operation 189

61. Complete and incomplete fistula 192

62. Tubercular fistula with fibrous infiltration 201

63. Showing Fig. 62 with wound sutured 202

64. Shoulder and knee strap applied 205

65. Earle's hawk-bill knife 207

66. First step in excision of fistula 209

67. Fistula threaded on a probe 210

68. Suturing after excision of fistula 211

69. Final step in closing fistula 212

70. Complex fistula 214

71. Incision for removing scar tissue 219

72. Chetwood's operation for fecal incontinence 221

73. Chetwood's operation, second step 222

74. Rectovaginal and vesicovaginal fistula 233

75. Lauenstein's operation for fistula 236

76. Closure of rectovaginal fistula 238

77. Mixed hemorrhoids 245

78. Thrombotic hemorrhoid 246

79. Pile ointment pipe 251

80. Collapsible metallic tube 251

81. Collier F. Martin's conical speculum 252

82. Diagrammatic sketch of injection points 254

83. Small electrothermic angiotribe 258

84. Shield for use with angiotribe 258

85. Transfixing hemorrhoid with needle 260

86. Turtle's hemorrhoidal forceps 262

87. Linthicum's hemorrhoidal clamp 263

ILLUSTRATIONS xiii

FIG. PAGE

SS. Murray's hemorrhoidal clamp 264

89. Earle's straight hemorrhoidal forceps 269

90. Hebb's modification of Fig. 89. 270

91. Earle's modification of Whitehead's operation 271

92. Second step of Fig. 91 . 272

93. Hebb's curved scissors 273

94. Fig. 91 completed 274

95. Modification of Earle's operation 276

96. Fig. 95 completed 277

97. Incomplete prolapse 279

98. Complete prolapse of rectum 283

99. Complete prolapse of rectum, third degree 284

100. Rectopexy for procidentia recti 292

101. Rectopexy — the gut brought through the incision 293

102. Rectopexy — the sutures through the tissues 294

103. Rectopexy — the operation completed 295

104. Sigmoidopexy — showing method of operation 297

105. Sigmoidopexy — incision }i inch from anal margin 300

106. Sigmoidopexy — clamp applied to gut 301

107. Sigmoidopexy — gut being sutured 302

108. Prolapse of uterus, vagina, and rectum 304

109. Fig. 108 with multiple adenoma 305

no. Olive-shaped, hard-rubber dilators 320

in. Cracked skin in pruritus ani 331

112. Elliptical incisions about anal margin 334

113. Flap dissected back, showing nerve filaments 334

114. Krouse's radial incisions 336

115. Inguinal colostomy, first step 341

116. Inguinal colostomy, second step 343

117. Inguinal colostomy, third step 344

118. Inguinal colostomy, completed 345

119. Compress and receiver, inguinal colostomy 346

120. Paul's intestinal tubes 347

121. Polypus from large hemorrhoid 356

122. Nevus simplex 361

123. Condyloma acuminatum 364

124. Inflammatory fibrous papilloma 365

125. Finger-like papillomatous outgrowths 365

126. Rectal adenoma 367

127. Multiple adenoma 368

128. Adenocarcinoma, alcohol specimen 375

129. Adenocarcinomatous ulcer. {Colored Plate.) 376

130. Colloid adenocarcinoma of the rectum 376

131. Photomicrograph of Fig. 130 2>77

132. Epithelioma of the anal margin 380

133. Adenocarcinoma 382

134. Perineal extirpation of rectum 405 xiv ILLUSTRATIONS

FIG. PAGE

135. Perineal extirpation — loosening rectum 406

136. Perineal extirpation — the pouch laid open 407

137. Perineal extirpation, completed 408

138. Extirpation of rectum by sacral route, first step 410

139. Rectum, with principal vessels. (Plate.) 410

140. Second step in bone-flap operation 411

141. Third step in bone-flap operation 412

142. Fifth step in bone-flap operation 413

143. Sacral anus 414

144. Incision in vaginal extirpation 418

145. Separation of rectum from vaginal walls 419

146. Colorectostomy (invagination of colon) 420

148. Gant's scissors for excising coccyx 448

149. Excision of the coccyx 448

150. Megacolon (Hirschsprung's disease) 453

151. Lateral anastomosis, ileum and sigmoid 459

152. Redundant sigmoid in four-year-old boy 460

DISEASES OF THE ANUS, RECTUM, AND SIGMOID

Chapter I

Before undertaking a study of the diseases of the anus, rectum, and colon it is necessary that their anatomy and physiology should be studied, or it will be impossible to understand their relation, interdependence, or treatment.

ANATOMY

Development. — The sigmoid and rectum are developed from the hypoblast and mesoblast of the ovum; the anus is developed from the epiblast. From the hypoblast the mucous membrane and probably the submucous tissue develop, while the inner layer of the mesoblast forms the muscular, peritoneal, and glandular portions of the bowel (Shaffer).

Up to the sixth week of gestation the large and small intestines are one cavity of nearly uniform calibre, with the exception of the lower portion of the hind-bowel. After the sixth week the colon and rectum grow more rapidly than the small intestine, and extend downward, approaching nearer the outer layer of the mesoblast and epiblast.

While this development of the rectum is going on an invagination of the epiblast takes place which is called the proctodeum. This invagination increases until the outer and inner layers of the mesoblast are pressed together and absorbed and the epiblast of the proctodeum and hypoblast of the hindgut approach each other and form a double septum between the rectum and the anus; finally this septum is absorbed and the continuity of the rectum with the anal canal is complete. The location of the septum, however, is marked by a narrow zone, whose superficial tissue is neither mucous nor cutaneous but a transitional form — mucocutaneous — which has been termed by Stroud the " pecten." The conjunction takes place generally at a point slightly in front of the posterior end of the gut, thus leaving a cul-de-sac which is connected with the neurenteric canal. This cul-de-sac, although largely absorbed during fetal life, becomes the coccygeal gland of Luschka.

Pig. i. — Divisions of the pelvic outlet — R.A., right anterior quadrant; L.A., left anterior quadrant; R.P., right posterior quadrant; L.P., left posterior quadrant; R.A. and L.A., uro-genital triangle; R.P. and L.P., rectal triangle.

Sometimes, through imperfect absorption, there may be a congenital posterior rectocele. It is from remains of this cul-de-sac that dermoid cysts frequently develop in the rectococcygeal space.

Pelvic Triangles. — The outlet of the bony pelvis forms an imperfect double triangle, which may be divided by an imaginary line running from the anterior border of one tuberosity of the ischium to that of the other into an anterior and a posterior triangle. The anterior one is known as the urogenital triangle and the posterior as the rectal triangle (Fig. i). The rectal triangle may be further subdivided by a line running from the symphysis pubis to the tip of the coccyx into the right and left anterior and posterior quadrants.

The urogenital triangle contains the genito-urinary organs. The rectal triangle contains the anus, rectum, and contiguous tissues. The relations of the parts filling in these two triangles must be thoroughly understood in order properly to appreciate and treat diseases of the rectum.

Fasciae. — The urogenital triangle is closed in by the perineum, which is bounded by the anus behind, the scrotum in front, and the ischiopubic rami and the ischial tuberosities upon the sides ; it is covered superficially by skin, the centre of which forms the raphe. Beneath the skin lies the superficial fascia, which is subdivided into a superficial and a deep layer. The deep layer is firm and close, and is attached at the sides to the entire lower border of the ischiopubic rami and the ischio tuberosities. Its posterior margin is united to the triangular ligament, that of the anterior margin, which is more especially associated with the genito-urinary organs, between which structure and the deep layer of fascia are the transversus perinae muscles. The superficial layer lies directly under the skin and is loose and areolar, its spaces being occupied with fat-cells.

The deep fascia of the perineum forms a triangle with its apex forward. It extends nearly horizontally sidewise between the lateral walls of the pelvis, and ventrodorsally from the pubic symphysis to the central point of the perineum, which is about an inch in front of the anus. At the base of the triangle the fascia is single, but immediately splits into two layers, the superficial and the deep, between which are situated a part of the urethra with certain of its appurtenances, vessels, and nerves. This is known as the triangular ligament of the urethra.

Fossae. — The ischiorectal fossae are the spaces posterior to the perineal spaces and separated from them by the wedgeshaped border of the perineal fascia and the transversus perinaei muscle. They are bounded by the levator ani muscle above, the obturator fascia, the obturator interims muscle, the ischium, and the sacro-ischiatic ligaments externally, the sacro-ischiatic and coccyx posteriorly, and the skin and superficial fasciae below. The ischiorectal spaces practically surround the posterior portions of the anus and rectum, are filled with fat and cellular tissue, and are connected by a zone of cellular tissue between the fibres of the levator ani muscle and the anococcygeal ligament. It is through this cellular tissue that pus finds its way from one fossa to the other. It is in these spaces that the blood-vessels and nerves to the anal canal and the surrounding tissues ramify, none of which, however, are of vital importance from a surgical standpoint.

Muscles of the Perinaei and of the Anorectal Region. — The transversus perinaei muscle crosses the posterior border of the perineum from one tuberosity of the ischium to the other, and nearly corresponds to the imaginary line directed to be drawn in dividing the bony outlet of the pelvis ; the accelerator urinae muscle runs through the centre of the space, being covered by the superficial fascia, and these, together with the external sphincter and the sphincter vaginae in women, unite just in front of the anus to form the common fibrous centre known as the perineal body.

The muscles that are of especial interest in the anatomy of the anorectal region are the corrugator cutis ani, the external and internal sphincters, the levator ani, the coccygeus and the rectococcygeus.

Corrugator Cutis Ani (Fig. 2). — This muscle consists of a thin layer of striated muscular fibres in the deeper layers of the skin surrounding the anus, which in contracting gathers the skin into folds.

External Sphincter (Fig. 2). — This muscle is composed of striated muscular fibres, which, however, have many properties resembling those of plain muscle, to be shown when the rectum is physiologically considered later on. It arises from the posterior surface of the coccyx and the fibrous layer of the skin over this region; passes forward to the posterior

White Line

T

Coiles Fascia

Obturator Fiscia

Perineal Shelf junction ofCo/lesFascia ' and base of ""

Ligament -r

Superficial Perineal A.

LevaYor Am M. />cce/erator_L/rmaeM. j Tuberosity of Ischium

I Transv?rkusPerinaeiM. T

Erector Penis, c t, 1

open, exposing , 1. to Corpus CavernoSL m ~ r ~A\t^\y £o theduib

'es Fascia

Cut end of In fen

Hemorrhoidal A . Corrugator Cotes Ani M. Obturator I

Fig. 2. — Male perinaeum.

Inferior Hemorrhoidal A .

_j_ G/uteusTtiaximus

Obturator Fascia laid open exposmd\_ **• reflected.

AlcocK* can*,. J c/3c/c/ f commissure of the anus, where its fibres divide to surround this aperture and reunites at the anterior commissure pass forward to be inserted into the perineal body. In women, some of its fibres are continuous in front with the fibres of the sphincter vagina. It is about three inches in length and half an inch in width. It is composed of a superficial and a deep layer. The fibres of the superficial layer are circular, and entirely surround the anus (Fig. 2) ; the fibres of the deeper layer are parallel, and lie on each side of the anal canal to' the height of about three-quarters of an inch.

Internal Sphincter. — This muscle is composed of an aggregation of the involuntary circular muscular fibres of the bowel ; it lies immediately above the external sphincter, from which it is separated by a narrow zone of connective tissue, and surrounds the upper portion of the anal canal. It is about one inch in width but is so variable in thickness that it cannot be accurately measured. The line of separation between the two sphincters is only perceptible to the touch.

A third sphincter which was formerly thought to exist is now conceded to be an aggregation of the circular muscular fibres found at the base of Houston's valves, also that these fibres extend into the layers of the valves.

Levator Ani (Figs. 2 and 3). — This is a broad sheet of muscular fibres which form the floor of the pelvis. It arises from the inner surface of the symphysis pubis, laterally from the pelvic fascia, where it becomes attached to the obturator fascia and posteriorly from the spine of the ischium on each side. Its anterior fibres pass downward and backward to> the central part of the perineum, embracing the prostate ; those at the rear pass downward and mesially to the coccyx, and the middle fibres, which constitute the bulk of the muscle, run downward and inward toward the middle line. Some are inserted in the wall of the anal canal and some into the median raphe in front of and behind the anal canal. The muscle as a whole is in the shape of a cone or shield, with its convex surface downward. The upper surface is covered with the rectovesical fascia. The two muscles, like all the perineal muscles, act in concert. Their contraction lifts the pelvic floor, and tends to counteract the action of the sphincters.

Coccygeus Muscle (Figs. 2 and 3). — This pair of muscles complete the muscular floor of the pelvis on each side so largely formed by the levator ani. They arise from the

-Levator ani muscle.

spine of the ischium, expand into a triangle, and are inserted into the margin of the coccyx and the last segment of the sacrum. They act with the levator and pull the coccyx forward when it has been displaced backward, as in defecation ( Gerrish ) .

Rectococcygeus Muscle. — These are two flat bands of unstriped muscular fibres which have been described by Kohlrausch and Treitz as arising from the coccygeal ligament near the tip of the coccyx, passing forward and downward, and finally blending with the longitudinal muscular fibres of the rectum and the pelvic fascia around the anus (Tuttle).

Nerve Supply of Anus and Rectum. — This comes from both sympathetic and cerebrospinal systems.

The Sympathetic Nerve Supply. — While in man the vertebral or stellate ganglia exist only as low as the first and sometimes the second lumbar nerves, there are yet visceral branches given off from the second, third, and fourth sacral

Fig. 4. — Sympathetic nerve supply to the rectum.

nerves to form a part of the nervi erigentes, which may be classed in the same category as autonomic nerves (Langley). These fibres pass directly to one of the prevertebral plexuses, chiefly the inferior hypogastric, or pelvic plexus, the latter of which is a thick network of fibres, rich in ganglia, which lies on either side of the rectum and is made up of a continuation of the hypogastric plexus, offsets from the upper sacral ganglia, and branches from the second, third, and fourth sacral nerves. From this plexus autonomic fibres are distributed to the rectum and internal sphincter (Fig. 4).

Cerebrospinal Nerve Supply (Fig. 5). — The cerebrospinal nerve supply to the lower portion of the rectum and anus comes almost entirely from the pudic nerve, which is made up of branches principally from the third, but also in part from the second and fourth, sacral nerves. The branches of the pudic nerve that supply the anus, surrounding muscles, and skin, are the inferior hemorrhoidal and the deep division of the anterior perineal nerve. The former distributes its branches in a fan-like manner to the external sphincter muscle and to the skin around the anus ; the latter also to the external sphincter, the levator ani, and the transversus perinaei muscles. It will thus be seen that the sympathetic nerve supply to the rectum and sphincter muscles comes from the lumbar and sacral portions of the cord; the cerebrospinal from the sacral portion of the cord only (Figs. 4 and 5).

Lymphatics of Anus and Rectum. — Quenu {Bull, de la Societe d'anatomie, Paris, 1893, p. 399) has shown the anus and rectum to be supplied with three sets of lymphatics, practically corresponding to the arterial supply, namely, the superior, middle, and inferior plexuses. These follow the course of the vessels, the lymphatic glands lying in close apposition with the hemorrhoidal veins.

The superior hemorrhoidal lymphatic plexus, which draws the lymph from the middle and upper portions of the rectum, connects with a chain of lymphatics which lie between the rectum and the anterior surfaces of the sacrum and coccyx, and after extending upward in the cellular tissue between the folds of the mesentery is connected with the prevertebral lymphatic system.

The middle hemorrhoidal lymphatic plexus, which originates in the mucous and submucous coats of the anterior portion of the rectum, empties into the hypogastric plexus.

The inferior hemorrhoidal lymphatic plexus, which originates in the anal and perineal region, does not follow the external hemorrhoidal veins very closely, but ramifies beneath the skin, and after passing forward and upward finally unites with the inguinal lymphatics. It also anastomoses with lym-

Fig. 5. — Sacral plexus.

phatics of the lower portion of the rectum. Clinical experience corroborates the connection that exists between the inferior hemorrhoidal lymphatics and the inguinal lymphatics, the latter being enlarged from malignant and specific disease of the anal margin.

Rectal folds

Sacrococcygeal, articulation

Hemorrhoidal veins.

Levator ani

External sphincter

Internal sphincter

.Seminal vesicle -Symphysis pubis

■Urethra !ulb of penis ■Internal sphincter .Levator ani

Veins of mucosa of anal canal £ /

Fold of mucous membrane External sphincter

Fig. 6. — Sagittal section of pelvis passing through rectum, anal canal, bladder, and urethra. (Piersol's Anatomy.)

ANAL CANAL

.The anal canal (Fig. 6) is a channel by which the rectum empties its contents externally. It is one inch long and runs downward and backward. It is lined with mucous membrane at the upper end and skin at the lower, with a mucocutaneous surface between the two. Outside of this lining the anal canal is surrounded at its lower portion by the external sphincter, some fibres of the levator ani, the longitudinal muscular fibres of the rectum throughout its extent, and the internal sphincter around the upper portion. The lateral walls of the tube are in contact, and the lining membrane is disposed in small, longitudinal folds. The distal aperture is the anus, and around it the skin is dark brown and puckered in radiating lines. Beneath the mucocutaneous lining of this canal, and separating it from the muscular layer, is a thin fibrocellular layer which closely unites the two adjoining layers. Its circumference is about one and three-sixteenth inches. The walls of the anal canal contain few glands and blood-vessels but are richly supplied with terminal nerves. The canal is covered in its lower portion by stratified squamous epithelium which undergoes a gradual transformation until it ends in the columnar epithelium of the mucous membrane at the anorectal line. There are slight elevations at this anorectal line above the surface of the adjoining mucosa, from five to eight in number, which assume the form of papillae at their summits. In a large majority of cases they are absent, or, at least, not noticeable, but when well developed they produce many reflex disturbances, which are accounted for by their abundant nerve-supply.

THE RECTUM

The rectum (Fig. 6) begins at the upper termination of the anal canal at the border of the crypts of Morgagni and terminates at a point opposite the front of the third sacral vertebra, where the large intestine ceases to be provided with a mesentery and where the three longitudinal muscular bands of the colon spread out and become equally distributed round the bowel. At this point a decided narrowing in the calibre of the bowel takes place. Its name, which means " straight," is made less absurd by the adoption of these terminal points, instead of extending it as formerly up to the sacro-iliac joint.

The rectum occupies the middle line and forms in its descent a double anterior posterior curve, the cavity of which is directed forward in the superior portion and backward in the inferior, and is divided into two parts. The upper, which is covered with peritoneum, is about three inches long and extends from the third sacral vertebra to the tip of the coccyx, its course conforming to the curve of these bones, to which it is attached posteriorly. The lower part, which is shorter, bends forward and terminates in a pouch close to the prostate gland in the male and the lower part of the vagina in the female.

The anal opening, instead of being at the end of this pouch and in the line of the curve of the rectum, is located in the

J?ECTO-SlG(^

CPENIN& lU.wAi.

O'BEIRNES SPR

VA!AE X-5

Bra*/

%0 ^ '

2Pm pF

Fig. 7. — Sagittal section of the rectum; Houston's valves, O'Beirne's sphincter.

under side, considerably in the rear of its blunt end. This pouch in front of the anal opening is known as the rectal ampulla.